diff --git a/cmd/postgres_exporter/datasource.go b/cmd/postgres_exporter/datasource.go
new file mode 100644
index 00000000..3bbe2f0a
--- /dev/null
+++ b/cmd/postgres_exporter/datasource.go
@@ -0,0 +1,168 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "fmt"
+ "io/ioutil"
+ "net/url"
+ "os"
+ "regexp"
+ "strings"
+
+ "github.com/go-kit/kit/log/level"
+ "github.com/prometheus/client_golang/prometheus"
+)
+
+func (e *Exporter) discoverDatabaseDSNs() []string {
+ // connstring syntax is complex (and not sure if even regular).
+ // we don't need to parse it, so just superficially validate that it starts
+ // with a valid-ish keyword pair
+ connstringRe := regexp.MustCompile(`^ *[a-zA-Z0-9]+ *= *[^= ]+`)
+
+ dsns := make(map[string]struct{})
+ for _, dsn := range e.dsn {
+ var dsnURI *url.URL
+ var dsnConnstring string
+
+ if strings.HasPrefix(dsn, "postgresql://") {
+ var err error
+ dsnURI, err = url.Parse(dsn)
+ if err != nil {
+ level.Error(logger).Log("msg", "Unable to parse DSN as URI", "dsn", loggableDSN(dsn), "err", err)
+ continue
+ }
+ } else if connstringRe.MatchString(dsn) {
+ dsnConnstring = dsn
+ } else {
+ level.Error(logger).Log("msg", "Unable to parse DSN as either URI or connstring", "dsn", loggableDSN(dsn))
+ continue
+ }
+
+ server, err := e.servers.GetServer(dsn)
+ if err != nil {
+ level.Error(logger).Log("msg", "Error opening connection to database", "dsn", loggableDSN(dsn), "err", err)
+ continue
+ }
+ dsns[dsn] = struct{}{}
+
+ // If autoDiscoverDatabases is true, set first dsn as master database (Default: false)
+ server.master = true
+
+ databaseNames, err := queryDatabases(server)
+ if err != nil {
+ level.Error(logger).Log("msg", "Error querying databases", "dsn", loggableDSN(dsn), "err", err)
+ continue
+ }
+ for _, databaseName := range databaseNames {
+ if contains(e.excludeDatabases, databaseName) {
+ continue
+ }
+
+ if len(e.includeDatabases) != 0 && !contains(e.includeDatabases, databaseName) {
+ continue
+ }
+
+ if dsnURI != nil {
+ dsnURI.Path = databaseName
+ dsn = dsnURI.String()
+ } else {
+ // replacing one dbname with another is complicated.
+ // just append new dbname to override.
+ dsn = fmt.Sprintf("%s dbname=%s", dsnConnstring, databaseName)
+ }
+ dsns[dsn] = struct{}{}
+ }
+ }
+
+ result := make([]string, len(dsns))
+ index := 0
+ for dsn := range dsns {
+ result[index] = dsn
+ index++
+ }
+
+ return result
+}
+
+func (e *Exporter) scrapeDSN(ch chan<- prometheus.Metric, dsn string) error {
+ server, err := e.servers.GetServer(dsn)
+
+ if err != nil {
+ return &ErrorConnectToServer{fmt.Sprintf("Error opening connection to database (%s): %s", loggableDSN(dsn), err.Error())}
+ }
+
+ // Check if autoDiscoverDatabases is false, set dsn as master database (Default: false)
+ if !e.autoDiscoverDatabases {
+ server.master = true
+ }
+
+ // Check if map versions need to be updated
+ if err := e.checkMapVersions(ch, server); err != nil {
+ level.Warn(logger).Log("msg", "Proceeding with outdated query maps, as the Postgres version could not be determined", "err", err)
+ }
+
+ return server.Scrape(ch, e.disableSettingsMetrics)
+}
+
+// try to get the DataSource
+// DATA_SOURCE_NAME always wins so we do not break older versions
+// reading secrets from files wins over secrets in environment variables
+// DATA_SOURCE_NAME > DATA_SOURCE_{USER|PASS}_FILE > DATA_SOURCE_{USER|PASS}
+func getDataSources() ([]string, error) {
+ var dsn = os.Getenv("DATA_SOURCE_NAME")
+ if len(dsn) != 0 {
+ return strings.Split(dsn, ","), nil
+ }
+
+ var user, pass, uri string
+
+ dataSourceUserFile := os.Getenv("DATA_SOURCE_USER_FILE")
+ if len(dataSourceUserFile) != 0 {
+ fileContents, err := ioutil.ReadFile(dataSourceUserFile)
+ if err != nil {
+ return nil, fmt.Errorf("failed loading data source user file %s: %s", dataSourceUserFile, err.Error())
+ }
+ user = strings.TrimSpace(string(fileContents))
+ } else {
+ user = os.Getenv("DATA_SOURCE_USER")
+ }
+
+ dataSourcePassFile := os.Getenv("DATA_SOURCE_PASS_FILE")
+ if len(dataSourcePassFile) != 0 {
+ fileContents, err := ioutil.ReadFile(dataSourcePassFile)
+ if err != nil {
+ return nil, fmt.Errorf("failed loading data source pass file %s: %s", dataSourcePassFile, err.Error())
+ }
+ pass = strings.TrimSpace(string(fileContents))
+ } else {
+ pass = os.Getenv("DATA_SOURCE_PASS")
+ }
+
+ ui := url.UserPassword(user, pass).String()
+ dataSrouceURIFile := os.Getenv("DATA_SOURCE_URI_FILE")
+ if len(dataSrouceURIFile) != 0 {
+ fileContents, err := ioutil.ReadFile(dataSrouceURIFile)
+ if err != nil {
+ return nil, fmt.Errorf("failed loading data source URI file %s: %s", dataSrouceURIFile, err.Error())
+ }
+ uri = strings.TrimSpace(string(fileContents))
+ } else {
+ uri = os.Getenv("DATA_SOURCE_URI")
+ }
+
+ dsn = "postgresql://" + ui + "@" + uri
+
+ return []string{dsn}, nil
+}
diff --git a/cmd/postgres_exporter/main.go b/cmd/postgres_exporter/main.go
new file mode 100644
index 00000000..25f94a74
--- /dev/null
+++ b/cmd/postgres_exporter/main.go
@@ -0,0 +1,129 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "net/http"
+ "os"
+
+ "github.com/go-kit/kit/log"
+ "github.com/go-kit/kit/log/level"
+ "github.com/prometheus/client_golang/prometheus"
+ "github.com/prometheus/client_golang/prometheus/promhttp"
+ "github.com/prometheus/common/promlog"
+ "github.com/prometheus/common/promlog/flag"
+ "github.com/prometheus/common/version"
+ "github.com/prometheus/exporter-toolkit/web"
+ webflag "github.com/prometheus/exporter-toolkit/web/kingpinflag"
+ "gopkg.in/alecthomas/kingpin.v2"
+)
+
+var (
+ listenAddress = kingpin.Flag("web.listen-address", "Address to listen on for web interface and telemetry.").Default(":9187").Envar("PG_EXPORTER_WEB_LISTEN_ADDRESS").String()
+ webConfig = webflag.AddFlags(kingpin.CommandLine)
+ metricPath = kingpin.Flag("web.telemetry-path", "Path under which to expose metrics.").Default("/metrics").Envar("PG_EXPORTER_WEB_TELEMETRY_PATH").String()
+ disableDefaultMetrics = kingpin.Flag("disable-default-metrics", "Do not include default metrics.").Default("false").Envar("PG_EXPORTER_DISABLE_DEFAULT_METRICS").Bool()
+ disableSettingsMetrics = kingpin.Flag("disable-settings-metrics", "Do not include pg_settings metrics.").Default("false").Envar("PG_EXPORTER_DISABLE_SETTINGS_METRICS").Bool()
+ autoDiscoverDatabases = kingpin.Flag("auto-discover-databases", "Whether to discover the databases on a server dynamically.").Default("false").Envar("PG_EXPORTER_AUTO_DISCOVER_DATABASES").Bool()
+ queriesPath = kingpin.Flag("extend.query-path", "Path to custom queries to run.").Default("").Envar("PG_EXPORTER_EXTEND_QUERY_PATH").String()
+ onlyDumpMaps = kingpin.Flag("dumpmaps", "Do not run, simply dump the maps.").Bool()
+ constantLabelsList = kingpin.Flag("constantLabels", "A list of label=value separated by comma(,).").Default("").Envar("PG_EXPORTER_CONSTANT_LABELS").String()
+ excludeDatabases = kingpin.Flag("exclude-databases", "A list of databases to remove when autoDiscoverDatabases is enabled").Default("").Envar("PG_EXPORTER_EXCLUDE_DATABASES").String()
+ includeDatabases = kingpin.Flag("include-databases", "A list of databases to include when autoDiscoverDatabases is enabled").Default("").Envar("PG_EXPORTER_INCLUDE_DATABASES").String()
+ metricPrefix = kingpin.Flag("metric-prefix", "A metric prefix can be used to have non-default (not \"pg\") prefixes for each of the metrics").Default("pg").Envar("PG_EXPORTER_METRIC_PREFIX").String()
+ logger = log.NewNopLogger()
+)
+
+// Metric name parts.
+const (
+ // Namespace for all metrics.
+ namespace = "pg"
+ // Subsystems.
+ exporter = "exporter"
+ // The name of the exporter.
+ exporterName = "postgres_exporter"
+ // Metric label used for static string data thats handy to send to Prometheus
+ // e.g. version
+ staticLabelName = "static"
+ // Metric label used for server identification.
+ serverLabelName = "server"
+)
+
+func main() {
+ kingpin.Version(version.Print(exporterName))
+ promlogConfig := &promlog.Config{}
+ flag.AddFlags(kingpin.CommandLine, promlogConfig)
+ kingpin.HelpFlag.Short('h')
+ kingpin.Parse()
+ logger = promlog.New(promlogConfig)
+
+ // landingPage contains the HTML served at '/'.
+ // TODO: Make this nicer and more informative.
+ var landingPage = []byte(`
+ Postgres exporter
+
+ Postgres exporter
+ Metrics
+
+
+ `)
+
+ if *onlyDumpMaps {
+ dumpMaps()
+ return
+ }
+
+ dsn, err := getDataSources()
+ if err != nil {
+ level.Error(logger).Log("msg", "Failed reading data sources", "err", err.Error())
+ os.Exit(1)
+ }
+
+ if len(dsn) == 0 {
+ level.Error(logger).Log("msg", "Couldn't find environment variables describing the datasource to use")
+ os.Exit(1)
+ }
+
+ opts := []ExporterOpt{
+ DisableDefaultMetrics(*disableDefaultMetrics),
+ DisableSettingsMetrics(*disableSettingsMetrics),
+ AutoDiscoverDatabases(*autoDiscoverDatabases),
+ WithUserQueriesPath(*queriesPath),
+ WithConstantLabels(*constantLabelsList),
+ ExcludeDatabases(*excludeDatabases),
+ IncludeDatabases(*includeDatabases),
+ }
+
+ exporter := NewExporter(dsn, opts...)
+ defer func() {
+ exporter.servers.Close()
+ }()
+
+ prometheus.MustRegister(version.NewCollector(exporterName))
+
+ prometheus.MustRegister(exporter)
+
+ http.Handle(*metricPath, promhttp.Handler())
+ http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+ w.Header().Set("Content-Type", "text/html; charset=UTF-8") // nolint: errcheck
+ w.Write(landingPage) // nolint: errcheck
+ })
+
+ level.Info(logger).Log("msg", "Listening on address", "address", *listenAddress)
+ srv := &http.Server{Addr: *listenAddress}
+ if err := web.ListenAndServe(srv, *webConfig, logger); err != nil {
+ level.Error(logger).Log("msg", "Error running HTTP server", "err", err)
+ os.Exit(1)
+ }
+}
diff --git a/cmd/postgres_exporter/namespace.go b/cmd/postgres_exporter/namespace.go
new file mode 100644
index 00000000..1b9e970e
--- /dev/null
+++ b/cmd/postgres_exporter/namespace.go
@@ -0,0 +1,264 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "database/sql"
+ "errors"
+ "fmt"
+ "time"
+
+ "github.com/blang/semver"
+ "github.com/go-kit/kit/log/level"
+ "github.com/lib/pq"
+ "github.com/prometheus/client_golang/prometheus"
+)
+
+// Query within a namespace mapping and emit metrics. Returns fatal errors if
+// the scrape fails, and a slice of errors if they were non-fatal.
+func queryNamespaceMapping(server *Server, namespace string, mapping MetricMapNamespace) ([]prometheus.Metric, []error, error) {
+ // Check for a query override for this namespace
+ query, found := server.queryOverrides[namespace]
+
+ // Was this query disabled (i.e. nothing sensible can be queried on cu
+ // version of PostgreSQL?
+ if query == "" && found {
+ // Return success (no pertinent data)
+ return []prometheus.Metric{}, []error{}, nil
+ }
+
+ // Don't fail on a bad scrape of one metric
+ var rows *sql.Rows
+ var err error
+
+ if !found {
+ // I've no idea how to avoid this properly at the moment, but this is
+ // an admin tool so you're not injecting SQL right?
+ rows, err = server.db.Query(fmt.Sprintf("SELECT * FROM %s;", namespace)) // nolint: gas
+ } else {
+ rows, err = server.db.Query(query)
+ }
+ if err != nil {
+ return []prometheus.Metric{}, []error{}, fmt.Errorf("Error running query on database %q: %s %v", server, namespace, err)
+ }
+ defer rows.Close() // nolint: errcheck
+
+ var columnNames []string
+ columnNames, err = rows.Columns()
+ if err != nil {
+ return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving column list for: ", namespace, err))
+ }
+
+ // Make a lookup map for the column indices
+ var columnIdx = make(map[string]int, len(columnNames))
+ for i, n := range columnNames {
+ columnIdx[n] = i
+ }
+
+ var columnData = make([]interface{}, len(columnNames))
+ var scanArgs = make([]interface{}, len(columnNames))
+ for i := range columnData {
+ scanArgs[i] = &columnData[i]
+ }
+
+ nonfatalErrors := []error{}
+
+ metrics := make([]prometheus.Metric, 0)
+
+ for rows.Next() {
+ err = rows.Scan(scanArgs...)
+ if err != nil {
+ return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving rows:", namespace, err))
+ }
+
+ // Get the label values for this row.
+ labels := make([]string, len(mapping.labels))
+ for idx, label := range mapping.labels {
+ labels[idx], _ = dbToString(columnData[columnIdx[label]])
+ }
+
+ // Loop over column names, and match to scan data. Unknown columns
+ // will be filled with an untyped metric number *if* they can be
+ // converted to float64s. NULLs are allowed and treated as NaN.
+ for idx, columnName := range columnNames {
+ var metric prometheus.Metric
+ if metricMapping, ok := mapping.columnMappings[columnName]; ok {
+ // Is this a metricy metric?
+ if metricMapping.discard {
+ continue
+ }
+
+ if metricMapping.histogram {
+ var keys []float64
+ err = pq.Array(&keys).Scan(columnData[idx])
+ if err != nil {
+ return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving", columnName, "buckets:", namespace, err))
+ }
+
+ var values []int64
+ valuesIdx, ok := columnIdx[columnName+"_bucket"]
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Missing column: ", namespace, columnName+"_bucket")))
+ continue
+ }
+ err = pq.Array(&values).Scan(columnData[valuesIdx])
+ if err != nil {
+ return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving", columnName, "bucket values:", namespace, err))
+ }
+
+ buckets := make(map[float64]uint64, len(keys))
+ for i, key := range keys {
+ if i >= len(values) {
+ break
+ }
+ buckets[key] = uint64(values[i])
+ }
+
+ idx, ok = columnIdx[columnName+"_sum"]
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Missing column: ", namespace, columnName+"_sum")))
+ continue
+ }
+ sum, ok := dbToFloat64(columnData[idx])
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unexpected error parsing column: ", namespace, columnName+"_sum", columnData[idx])))
+ continue
+ }
+
+ idx, ok = columnIdx[columnName+"_count"]
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Missing column: ", namespace, columnName+"_count")))
+ continue
+ }
+ count, ok := dbToUint64(columnData[idx])
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unexpected error parsing column: ", namespace, columnName+"_count", columnData[idx])))
+ continue
+ }
+
+ metric = prometheus.MustNewConstHistogram(
+ metricMapping.desc,
+ count, sum, buckets,
+ labels...,
+ )
+ } else {
+ value, ok := dbToFloat64(columnData[idx])
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unexpected error parsing column: ", namespace, columnName, columnData[idx])))
+ continue
+ }
+ // Generate the metric
+ metric = prometheus.MustNewConstMetric(metricMapping.desc, metricMapping.vtype, value, labels...)
+ }
+ } else {
+ // Unknown metric. Report as untyped if scan to float64 works, else note an error too.
+ metricLabel := fmt.Sprintf("%s_%s", namespace, columnName)
+ desc := prometheus.NewDesc(metricLabel, fmt.Sprintf("Unknown metric from %s", namespace), mapping.labels, server.labels)
+
+ // Its not an error to fail here, since the values are
+ // unexpected anyway.
+ value, ok := dbToFloat64(columnData[idx])
+ if !ok {
+ nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unparseable column type - discarding: ", namespace, columnName, err)))
+ continue
+ }
+ metric = prometheus.MustNewConstMetric(desc, prometheus.UntypedValue, value, labels...)
+ }
+ metrics = append(metrics, metric)
+ }
+ }
+ return metrics, nonfatalErrors, nil
+}
+
+// Iterate through all the namespace mappings in the exporter and run their
+// queries.
+func queryNamespaceMappings(ch chan<- prometheus.Metric, server *Server) map[string]error {
+ // Return a map of namespace -> errors
+ namespaceErrors := make(map[string]error)
+
+ scrapeStart := time.Now()
+
+ for namespace, mapping := range server.metricMap {
+ level.Debug(logger).Log("msg", "Querying namespace", "namespace", namespace)
+
+ if mapping.master && !server.master {
+ level.Debug(logger).Log("msg", "Query skipped...")
+ continue
+ }
+
+ // check if the query is to be run on specific database server version range or not
+ if len(server.runonserver) > 0 {
+ serVersion, _ := semver.Parse(server.lastMapVersion.String())
+ runServerRange, _ := semver.ParseRange(server.runonserver)
+ if !runServerRange(serVersion) {
+ level.Debug(logger).Log("msg", "Query skipped for this database version", "version", server.lastMapVersion.String(), "target_version", server.runonserver)
+ continue
+ }
+ }
+
+ scrapeMetric := false
+ // Check if the metric is cached
+ server.cacheMtx.Lock()
+ cachedMetric, found := server.metricCache[namespace]
+ server.cacheMtx.Unlock()
+ // If found, check if needs refresh from cache
+ if found {
+ if scrapeStart.Sub(cachedMetric.lastScrape).Seconds() > float64(mapping.cacheSeconds) {
+ scrapeMetric = true
+ }
+ } else {
+ scrapeMetric = true
+ }
+
+ var metrics []prometheus.Metric
+ var nonFatalErrors []error
+ var err error
+ if scrapeMetric {
+ metrics, nonFatalErrors, err = queryNamespaceMapping(server, namespace, mapping)
+ } else {
+ metrics = cachedMetric.metrics
+ }
+
+ // Serious error - a namespace disappeared
+ if err != nil {
+ namespaceErrors[namespace] = err
+ level.Info(logger).Log("err", err)
+ }
+ // Non-serious errors - likely version or parsing problems.
+ if len(nonFatalErrors) > 0 {
+ for _, err := range nonFatalErrors {
+ level.Info(logger).Log("err", err)
+ }
+ }
+
+ // Emit the metrics into the channel
+ for _, metric := range metrics {
+ ch <- metric
+ }
+
+ if scrapeMetric {
+ // Only cache if metric is meaningfully cacheable
+ if mapping.cacheSeconds > 0 {
+ server.cacheMtx.Lock()
+ server.metricCache[namespace] = cachedMetrics{
+ metrics: metrics,
+ lastScrape: scrapeStart,
+ }
+ server.cacheMtx.Unlock()
+ }
+ }
+ }
+
+ return namespaceErrors
+}
diff --git a/cmd/postgres_exporter/postgres_exporter.go b/cmd/postgres_exporter/postgres_exporter.go
index b2e9f75b..15804811 100644
--- a/cmd/postgres_exporter/postgres_exporter.go
+++ b/cmd/postgres_exporter/postgres_exporter.go
@@ -20,74 +20,34 @@ import (
"fmt"
"io/ioutil"
"math"
- "net/http"
- "net/url"
- "os"
"regexp"
- "strconv"
"strings"
- "sync"
"time"
"github.com/blang/semver"
- "github.com/go-kit/kit/log"
"github.com/go-kit/kit/log/level"
- "github.com/lib/pq"
"github.com/prometheus/client_golang/prometheus"
- "github.com/prometheus/client_golang/prometheus/promhttp"
- "github.com/prometheus/common/promlog"
- "github.com/prometheus/common/promlog/flag"
- "github.com/prometheus/common/version"
- "github.com/prometheus/exporter-toolkit/web"
- webflag "github.com/prometheus/exporter-toolkit/web/kingpinflag"
- "gopkg.in/alecthomas/kingpin.v2"
- "gopkg.in/yaml.v2"
-)
-
-var (
- listenAddress = kingpin.Flag("web.listen-address", "Address to listen on for web interface and telemetry.").Default(":9187").Envar("PG_EXPORTER_WEB_LISTEN_ADDRESS").String()
- webConfig = webflag.AddFlags(kingpin.CommandLine)
- metricPath = kingpin.Flag("web.telemetry-path", "Path under which to expose metrics.").Default("/metrics").Envar("PG_EXPORTER_WEB_TELEMETRY_PATH").String()
- disableDefaultMetrics = kingpin.Flag("disable-default-metrics", "Do not include default metrics.").Default("false").Envar("PG_EXPORTER_DISABLE_DEFAULT_METRICS").Bool()
- disableSettingsMetrics = kingpin.Flag("disable-settings-metrics", "Do not include pg_settings metrics.").Default("false").Envar("PG_EXPORTER_DISABLE_SETTINGS_METRICS").Bool()
- autoDiscoverDatabases = kingpin.Flag("auto-discover-databases", "Whether to discover the databases on a server dynamically.").Default("false").Envar("PG_EXPORTER_AUTO_DISCOVER_DATABASES").Bool()
- queriesPath = kingpin.Flag("extend.query-path", "Path to custom queries to run.").Default("").Envar("PG_EXPORTER_EXTEND_QUERY_PATH").String()
- onlyDumpMaps = kingpin.Flag("dumpmaps", "Do not run, simply dump the maps.").Bool()
- constantLabelsList = kingpin.Flag("constantLabels", "A list of label=value separated by comma(,).").Default("").Envar("PG_EXPORTER_CONSTANT_LABELS").String()
- excludeDatabases = kingpin.Flag("exclude-databases", "A list of databases to remove when autoDiscoverDatabases is enabled").Default("").Envar("PG_EXPORTER_EXCLUDE_DATABASES").String()
- includeDatabases = kingpin.Flag("include-databases", "A list of databases to include when autoDiscoverDatabases is enabled").Default("").Envar("PG_EXPORTER_INCLUDE_DATABASES").String()
- metricPrefix = kingpin.Flag("metric-prefix", "A metric prefix can be used to have non-default (not \"pg\") prefixes for each of the metrics").Default("pg").Envar("PG_EXPORTER_METRIC_PREFIX").String()
- logger = log.NewNopLogger()
-)
-
-// Metric name parts.
-const (
- // Namespace for all metrics.
- namespace = "pg"
- // Subsystems.
- exporter = "exporter"
- // The name of the exporter.
- exporterName = "postgres_exporter"
- // Metric label used for static string data thats handy to send to Prometheus
- // e.g. version
- staticLabelName = "static"
- // Metric label used for server identification.
- serverLabelName = "server"
)
// ColumnUsage should be one of several enum values which describe how a
// queried row is to be converted to a Prometheus metric.
type ColumnUsage int
-// nolint: golint
const (
- DISCARD ColumnUsage = iota // Ignore this column
- LABEL ColumnUsage = iota // Use this column as a label
- COUNTER ColumnUsage = iota // Use this column as a counter
- GAUGE ColumnUsage = iota // Use this column as a gauge
- MAPPEDMETRIC ColumnUsage = iota // Use this column with the supplied mapping of text values
- DURATION ColumnUsage = iota // This column should be interpreted as a text duration (and converted to milliseconds)
- HISTOGRAM ColumnUsage = iota // Use this column as a histogram
+ // DISCARD ignores a column
+ DISCARD ColumnUsage = iota
+ // LABEL identifies a column as a label
+ LABEL ColumnUsage = iota
+ // COUNTER identifies a column as a counter
+ COUNTER ColumnUsage = iota
+ // GAUGE identifies a column as a gauge
+ GAUGE ColumnUsage = iota
+ // MAPPEDMETRIC identifies a column as a mapping of text values
+ MAPPEDMETRIC ColumnUsage = iota
+ // DURATION identifies a column as a text duration (and converted to milliseconds)
+ DURATION ColumnUsage = iota
+ // HISTOGRAM identifies a column as a histogram
+ HISTOGRAM ColumnUsage = iota
)
// UnmarshalYAML implements the yaml.Unmarshaller interface.
@@ -114,21 +74,9 @@ type MappingOptions struct {
SupportedVersions semver.Range `yaml:"pg_version"` // Semantic version ranges which are supported. Unsupported columns are not queried (internally converted to DISCARD).
}
-// nolint: golint
+// Mapping represents a set of MappingOptions
type Mapping map[string]MappingOptions
-// nolint: golint
-type UserQuery struct {
- Query string `yaml:"query"`
- Metrics []Mapping `yaml:"metrics"`
- Master bool `yaml:"master"` // Querying only for master database
- CacheSeconds uint64 `yaml:"cache_seconds"` // Number of seconds to cache the namespace result metrics for.
- RunOnServer string `yaml:"runonserver"` // Querying to run on which server version
-}
-
-// nolint: golint
-type UserQueries map[string]UserQuery
-
// Regex used to get the "short-version" from the postgres version field.
var versionRegex = regexp.MustCompile(`^\w+ ((\d+)(\.\d+)?(\.\d+)?)`)
var lowestSupportedVersion = semver.MustParse("9.1.0")
@@ -361,254 +309,6 @@ var builtinMetricMaps = map[string]intermediateMetricMap{
},
}
-// OverrideQuery 's are run in-place of simple namespace look ups, and provide
-// advanced functionality. But they have a tendency to postgres version specific.
-// There aren't too many versions, so we simply store customized versions using
-// the semver matching we do for columns.
-type OverrideQuery struct {
- versionRange semver.Range
- query string
-}
-
-// Overriding queries for namespaces above.
-// TODO: validate this is a closed set in tests, and there are no overlaps
-var queryOverrides = map[string][]OverrideQuery{
- "pg_locks": {
- {
- semver.MustParseRange(">0.0.0"),
- `SELECT pg_database.datname,tmp.mode,COALESCE(count,0) as count
- FROM
- (
- VALUES ('accesssharelock'),
- ('rowsharelock'),
- ('rowexclusivelock'),
- ('shareupdateexclusivelock'),
- ('sharelock'),
- ('sharerowexclusivelock'),
- ('exclusivelock'),
- ('accessexclusivelock'),
- ('sireadlock')
- ) AS tmp(mode) CROSS JOIN pg_database
- LEFT JOIN
- (SELECT database, lower(mode) AS mode,count(*) AS count
- FROM pg_locks WHERE database IS NOT NULL
- GROUP BY database, lower(mode)
- ) AS tmp2
- ON tmp.mode=tmp2.mode and pg_database.oid = tmp2.database ORDER BY 1`,
- },
- },
-
- "pg_stat_replication": {
- {
- semver.MustParseRange(">=10.0.0"),
- `
- SELECT *,
- (case pg_is_in_recovery() when 't' then null else pg_current_wal_lsn() end) AS pg_current_wal_lsn,
- (case pg_is_in_recovery() when 't' then null else pg_wal_lsn_diff(pg_current_wal_lsn(), pg_lsn('0/0'))::float end) AS pg_current_wal_lsn_bytes,
- (case pg_is_in_recovery() when 't' then null else pg_wal_lsn_diff(pg_current_wal_lsn(), replay_lsn)::float end) AS pg_wal_lsn_diff
- FROM pg_stat_replication
- `,
- },
- {
- semver.MustParseRange(">=9.2.0 <10.0.0"),
- `
- SELECT *,
- (case pg_is_in_recovery() when 't' then null else pg_current_xlog_location() end) AS pg_current_xlog_location,
- (case pg_is_in_recovery() when 't' then null else pg_xlog_location_diff(pg_current_xlog_location(), replay_location)::float end) AS pg_xlog_location_diff
- FROM pg_stat_replication
- `,
- },
- {
- semver.MustParseRange("<9.2.0"),
- `
- SELECT *,
- (case pg_is_in_recovery() when 't' then null else pg_current_xlog_location() end) AS pg_current_xlog_location
- FROM pg_stat_replication
- `,
- },
- },
-
- "pg_replication_slots": {
- {
- semver.MustParseRange(">=9.4.0 <10.0.0"),
- `
- SELECT slot_name, database, active, pg_xlog_location_diff(pg_current_xlog_location(), restart_lsn)
- FROM pg_replication_slots
- `,
- },
- {
- semver.MustParseRange(">=10.0.0"),
- `
- SELECT slot_name, database, active, pg_wal_lsn_diff(pg_current_wal_lsn(), restart_lsn)
- FROM pg_replication_slots
- `,
- },
- },
-
- "pg_stat_archiver": {
- {
- semver.MustParseRange(">=0.0.0"),
- `
- SELECT *,
- extract(epoch from now() - last_archived_time) AS last_archive_age
- FROM pg_stat_archiver
- `,
- },
- },
-
- "pg_stat_activity": {
- // This query only works
- {
- semver.MustParseRange(">=9.2.0"),
- `
- SELECT
- pg_database.datname,
- tmp.state,
- COALESCE(count,0) as count,
- COALESCE(max_tx_duration,0) as max_tx_duration
- FROM
- (
- VALUES ('active'),
- ('idle'),
- ('idle in transaction'),
- ('idle in transaction (aborted)'),
- ('fastpath function call'),
- ('disabled')
- ) AS tmp(state) CROSS JOIN pg_database
- LEFT JOIN
- (
- SELECT
- datname,
- state,
- count(*) AS count,
- MAX(EXTRACT(EPOCH FROM now() - xact_start))::float AS max_tx_duration
- FROM pg_stat_activity GROUP BY datname,state) AS tmp2
- ON tmp.state = tmp2.state AND pg_database.datname = tmp2.datname
- `,
- },
- {
- semver.MustParseRange("<9.2.0"),
- `
- SELECT
- datname,
- 'unknown' AS state,
- COALESCE(count(*),0) AS count,
- COALESCE(MAX(EXTRACT(EPOCH FROM now() - xact_start))::float,0) AS max_tx_duration
- FROM pg_stat_activity GROUP BY datname
- `,
- },
- },
-}
-
-// Convert the query override file to the version-specific query override file
-// for the exporter.
-func makeQueryOverrideMap(pgVersion semver.Version, queryOverrides map[string][]OverrideQuery) map[string]string {
- resultMap := make(map[string]string)
- for name, overrideDef := range queryOverrides {
- // Find a matching semver. We make it an error to have overlapping
- // ranges at test-time, so only 1 should ever match.
- matched := false
- for _, queryDef := range overrideDef {
- if queryDef.versionRange(pgVersion) {
- resultMap[name] = queryDef.query
- matched = true
- break
- }
- }
- if !matched {
- level.Warn(logger).Log("msg", "No query matched override, disabling metric space", "name", name)
- resultMap[name] = ""
- }
- }
-
- return resultMap
-}
-
-func parseUserQueries(content []byte) (map[string]intermediateMetricMap, map[string]string, error) {
- var userQueries UserQueries
-
- err := yaml.Unmarshal(content, &userQueries)
- if err != nil {
- return nil, nil, err
- }
-
- // Stores the loaded map representation
- metricMaps := make(map[string]intermediateMetricMap)
- newQueryOverrides := make(map[string]string)
-
- for metric, specs := range userQueries {
- level.Debug(logger).Log("msg", "New user metric namespace from YAML metric", "metric", metric, "cache_seconds", specs.CacheSeconds)
- newQueryOverrides[metric] = specs.Query
- metricMap, ok := metricMaps[metric]
- if !ok {
- // Namespace for metric not found - add it.
- newMetricMap := make(map[string]ColumnMapping)
- metricMap = intermediateMetricMap{
- columnMappings: newMetricMap,
- master: specs.Master,
- cacheSeconds: specs.CacheSeconds,
- }
- metricMaps[metric] = metricMap
- }
- for _, metric := range specs.Metrics {
- for name, mappingOption := range metric {
- var columnMapping ColumnMapping
- tmpUsage, _ := stringToColumnUsage(mappingOption.Usage)
- columnMapping.usage = tmpUsage
- columnMapping.description = mappingOption.Description
-
- // TODO: we should support cu
- columnMapping.mapping = nil
- // Should we support this for users?
- columnMapping.supportedVersions = nil
-
- metricMap.columnMappings[name] = columnMapping
- }
- }
- }
- return metricMaps, newQueryOverrides, nil
-}
-
-// Add queries to the builtinMetricMaps and queryOverrides maps. Added queries do not
-// respect version requirements, because it is assumed that the user knows
-// what they are doing with their version of postgres.
-//
-// This function modifies metricMap and queryOverrideMap to contain the new
-// queries.
-// TODO: test code for all cu.
-// TODO: the YAML this supports is "non-standard" - we should move away from it.
-func addQueries(content []byte, pgVersion semver.Version, server *Server) error {
- metricMaps, newQueryOverrides, err := parseUserQueries(content)
- if err != nil {
- return err
- }
- // Convert the loaded metric map into exporter representation
- partialExporterMap := makeDescMap(pgVersion, server.labels, metricMaps)
-
- // Merge the two maps (which are now quite flatteend)
- for k, v := range partialExporterMap {
- _, found := server.metricMap[k]
- if found {
- level.Debug(logger).Log("msg", "Overriding metric from user YAML file", "metric", k)
- } else {
- level.Debug(logger).Log("msg", "Adding new metric from user YAML file", "metric", k)
- }
- server.metricMap[k] = v
- }
-
- // Merge the query override map
- for k, v := range newQueryOverrides {
- _, found := server.queryOverrides[k]
- if found {
- level.Debug(logger).Log("msg", "Overriding query override from user YAML file", "query_override", k)
- } else {
- level.Debug(logger).Log("msg", "Adding new query override from user YAML file", "query_override", k)
- }
- server.queryOverrides[k] = v
- }
- return nil
-}
-
// Turn the MetricMap column mapping into a prometheus descriptor mapping.
func makeDescMap(pgVersion semver.Version, serverLabels prometheus.Labels, metricMaps map[string]intermediateMetricMap) map[string]MetricMapNamespace {
var metricMap = make(map[string]MetricMapNamespace)
@@ -745,359 +445,11 @@ func makeDescMap(pgVersion semver.Version, serverLabels prometheus.Labels, metri
return metricMap
}
-// convert a string to the corresponding ColumnUsage
-func stringToColumnUsage(s string) (ColumnUsage, error) {
- var u ColumnUsage
- var err error
- switch s {
- case "DISCARD":
- u = DISCARD
-
- case "LABEL":
- u = LABEL
-
- case "COUNTER":
- u = COUNTER
-
- case "GAUGE":
- u = GAUGE
-
- case "HISTOGRAM":
- u = HISTOGRAM
-
- case "MAPPEDMETRIC":
- u = MAPPEDMETRIC
-
- case "DURATION":
- u = DURATION
-
- default:
- err = fmt.Errorf("wrong ColumnUsage given : %s", s)
- }
-
- return u, err
-}
-
-// Convert database.sql types to float64s for Prometheus consumption. Null types are mapped to NaN. string and []byte
-// types are mapped as NaN and !ok
-func dbToFloat64(t interface{}) (float64, bool) {
- switch v := t.(type) {
- case int64:
- return float64(v), true
- case float64:
- return v, true
- case time.Time:
- return float64(v.Unix()), true
- case []byte:
- // Try and convert to string and then parse to a float64
- strV := string(v)
- result, err := strconv.ParseFloat(strV, 64)
- if err != nil {
- level.Info(logger).Log("msg", "Could not parse []byte", "err", err)
- return math.NaN(), false
- }
- return result, true
- case string:
- result, err := strconv.ParseFloat(v, 64)
- if err != nil {
- level.Info(logger).Log("msg", "Could not parse string", "err", err)
- return math.NaN(), false
- }
- return result, true
- case bool:
- if v {
- return 1.0, true
- }
- return 0.0, true
- case nil:
- return math.NaN(), true
- default:
- return math.NaN(), false
- }
-}
-
-// Convert database.sql types to uint64 for Prometheus consumption. Null types are mapped to 0. string and []byte
-// types are mapped as 0 and !ok
-func dbToUint64(t interface{}) (uint64, bool) {
- switch v := t.(type) {
- case uint64:
- return v, true
- case int64:
- return uint64(v), true
- case float64:
- return uint64(v), true
- case time.Time:
- return uint64(v.Unix()), true
- case []byte:
- // Try and convert to string and then parse to a uint64
- strV := string(v)
- result, err := strconv.ParseUint(strV, 10, 64)
- if err != nil {
- level.Info(logger).Log("msg", "Could not parse []byte", "err", err)
- return 0, false
- }
- return result, true
- case string:
- result, err := strconv.ParseUint(v, 10, 64)
- if err != nil {
- level.Info(logger).Log("msg", "Could not parse string", "err", err)
- return 0, false
- }
- return result, true
- case bool:
- if v {
- return 1, true
- }
- return 0, true
- case nil:
- return 0, true
- default:
- return 0, false
- }
-}
-
-// Convert database.sql to string for Prometheus labels. Null types are mapped to empty strings.
-func dbToString(t interface{}) (string, bool) {
- switch v := t.(type) {
- case int64:
- return fmt.Sprintf("%v", v), true
- case float64:
- return fmt.Sprintf("%v", v), true
- case time.Time:
- return fmt.Sprintf("%v", v.Unix()), true
- case nil:
- return "", true
- case []byte:
- // Try and convert to string
- return string(v), true
- case string:
- return v, true
- case bool:
- if v {
- return "true", true
- }
- return "false", true
- default:
- return "", false
- }
-}
-
-func parseFingerprint(url string) (string, error) {
- dsn, err := pq.ParseURL(url)
- if err != nil {
- dsn = url
- }
-
- pairs := strings.Split(dsn, " ")
- kv := make(map[string]string, len(pairs))
- for _, pair := range pairs {
- splitted := strings.SplitN(pair, "=", 2)
- if len(splitted) != 2 {
- return "", fmt.Errorf("malformed dsn %q", dsn)
- }
- kv[splitted[0]] = splitted[1]
- }
-
- var fingerprint string
-
- if host, ok := kv["host"]; ok {
- fingerprint += host
- } else {
- fingerprint += "localhost"
- }
-
- if port, ok := kv["port"]; ok {
- fingerprint += ":" + port
- } else {
- fingerprint += ":5432"
- }
-
- return fingerprint, nil
-}
-
-func loggableDSN(dsn string) string {
- pDSN, err := url.Parse(dsn)
- if err != nil {
- return "could not parse DATA_SOURCE_NAME"
- }
- // Blank user info if not nil
- if pDSN.User != nil {
- pDSN.User = url.UserPassword(pDSN.User.Username(), "PASSWORD_REMOVED")
- }
-
- return pDSN.String()
-}
-
type cachedMetrics struct {
metrics []prometheus.Metric
lastScrape time.Time
}
-// Server describes a connection to Postgres.
-// Also it contains metrics map and query overrides.
-type Server struct {
- db *sql.DB
- labels prometheus.Labels
- master bool
- runonserver string
-
- // Last version used to calculate metric map. If mismatch on scrape,
- // then maps are recalculated.
- lastMapVersion semver.Version
- // Currently active metric map
- metricMap map[string]MetricMapNamespace
- // Currently active query overrides
- queryOverrides map[string]string
- mappingMtx sync.RWMutex
- // Currently cached metrics
- metricCache map[string]cachedMetrics
- cacheMtx sync.Mutex
-}
-
-// ServerOpt configures a server.
-type ServerOpt func(*Server)
-
-// ServerWithLabels configures a set of labels.
-func ServerWithLabels(labels prometheus.Labels) ServerOpt {
- return func(s *Server) {
- for k, v := range labels {
- s.labels[k] = v
- }
- }
-}
-
-// NewServer establishes a new connection using DSN.
-func NewServer(dsn string, opts ...ServerOpt) (*Server, error) {
- fingerprint, err := parseFingerprint(dsn)
- if err != nil {
- return nil, err
- }
-
- db, err := sql.Open("postgres", dsn)
- if err != nil {
- return nil, err
- }
- db.SetMaxOpenConns(1)
- db.SetMaxIdleConns(1)
-
- level.Info(logger).Log("msg", "Established new database connection", "fingerprint", fingerprint)
-
- s := &Server{
- db: db,
- master: false,
- labels: prometheus.Labels{
- serverLabelName: fingerprint,
- },
- metricCache: make(map[string]cachedMetrics),
- }
-
- for _, opt := range opts {
- opt(s)
- }
-
- return s, nil
-}
-
-// Close disconnects from Postgres.
-func (s *Server) Close() error {
- return s.db.Close()
-}
-
-// Ping checks connection availability and possibly invalidates the connection if it fails.
-func (s *Server) Ping() error {
- if err := s.db.Ping(); err != nil {
- if cerr := s.Close(); cerr != nil {
- level.Error(logger).Log("msg", "Error while closing non-pinging DB connection", "server", s, "err", cerr)
- }
- return err
- }
- return nil
-}
-
-// String returns server's fingerprint.
-func (s *Server) String() string {
- return s.labels[serverLabelName]
-}
-
-// Scrape loads metrics.
-func (s *Server) Scrape(ch chan<- prometheus.Metric, disableSettingsMetrics bool) error {
- s.mappingMtx.RLock()
- defer s.mappingMtx.RUnlock()
-
- var err error
-
- if !disableSettingsMetrics && s.master {
- if err = querySettings(ch, s); err != nil {
- err = fmt.Errorf("error retrieving settings: %s", err)
- }
- }
-
- errMap := queryNamespaceMappings(ch, s)
- if len(errMap) > 0 {
- err = fmt.Errorf("queryNamespaceMappings returned %d errors", len(errMap))
- }
-
- return err
-}
-
-// Servers contains a collection of servers to Postgres.
-type Servers struct {
- m sync.Mutex
- servers map[string]*Server
- opts []ServerOpt
-}
-
-// NewServers creates a collection of servers to Postgres.
-func NewServers(opts ...ServerOpt) *Servers {
- return &Servers{
- servers: make(map[string]*Server),
- opts: opts,
- }
-}
-
-// GetServer returns established connection from a collection.
-func (s *Servers) GetServer(dsn string) (*Server, error) {
- s.m.Lock()
- defer s.m.Unlock()
- var err error
- var ok bool
- errCount := 0 // start at zero because we increment before doing work
- retries := 1
- var server *Server
- for {
- if errCount++; errCount > retries {
- return nil, err
- }
- server, ok = s.servers[dsn]
- if !ok {
- server, err = NewServer(dsn, s.opts...)
- if err != nil {
- time.Sleep(time.Duration(errCount) * time.Second)
- continue
- }
- s.servers[dsn] = server
- }
- if err = server.Ping(); err != nil {
- delete(s.servers, dsn)
- time.Sleep(time.Duration(errCount) * time.Second)
- continue
- }
- break
- }
- return server, nil
-}
-
-// Close disconnects from all known servers.
-func (s *Servers) Close() {
- s.m.Lock()
- defer s.m.Unlock()
- for _, server := range s.servers {
- if err := server.Close(); err != nil {
- level.Error(logger).Log("msg", "Failed to close connection", "server", server, "err", err)
- }
- }
-}
-
// Exporter collects Postgres metrics. It implements prometheus.Collector.
type Exporter struct {
// Holds a reference to the build in column mappings. Currently this is for testing purposes
@@ -1214,15 +566,11 @@ func NewExporter(dsn []string, opts ...ExporterOpt) *Exporter {
}
e.setupInternalMetrics()
- e.setupServers()
+ e.servers = NewServers(ServerWithLabels(e.constantLabels))
return e
}
-func (e *Exporter) setupServers() {
- e.servers = NewServers(ServerWithLabels(e.constantLabels))
-}
-
func (e *Exporter) setupInternalMetrics() {
e.duration = prometheus.NewGauge(prometheus.GaugeOpts{
Namespace: namespace,
@@ -1282,277 +630,29 @@ func newDesc(subsystem, name, help string, labels prometheus.Labels) *prometheus
)
}
-func queryDatabases(server *Server) ([]string, error) {
- rows, err := server.db.Query("SELECT datname FROM pg_database WHERE datallowconn = true AND datistemplate = false AND datname != current_database()")
+func checkPostgresVersion(db *sql.DB, server string) (semver.Version, string, error) {
+ level.Debug(logger).Log("msg", "Querying PostgreSQL version", "server", server)
+ versionRow := db.QueryRow("SELECT version();")
+ var versionString string
+ err := versionRow.Scan(&versionString)
if err != nil {
- return nil, fmt.Errorf("Error retrieving databases: %v", err)
- }
- defer rows.Close() // nolint: errcheck
-
- var databaseName string
- result := make([]string, 0)
- for rows.Next() {
- err = rows.Scan(&databaseName)
- if err != nil {
- return nil, errors.New(fmt.Sprintln("Error retrieving rows:", err))
- }
- result = append(result, databaseName)
- }
-
- return result, nil
-}
-
-// Query within a namespace mapping and emit metrics. Returns fatal errors if
-// the scrape fails, and a slice of errors if they were non-fatal.
-func queryNamespaceMapping(server *Server, namespace string, mapping MetricMapNamespace) ([]prometheus.Metric, []error, error) {
- // Check for a query override for this namespace
- query, found := server.queryOverrides[namespace]
-
- // Was this query disabled (i.e. nothing sensible can be queried on cu
- // version of PostgreSQL?
- if query == "" && found {
- // Return success (no pertinent data)
- return []prometheus.Metric{}, []error{}, nil
- }
-
- // Don't fail on a bad scrape of one metric
- var rows *sql.Rows
- var err error
-
- if !found {
- // I've no idea how to avoid this properly at the moment, but this is
- // an admin tool so you're not injecting SQL right?
- rows, err = server.db.Query(fmt.Sprintf("SELECT * FROM %s;", namespace)) // nolint: gas
- } else {
- rows, err = server.db.Query(query)
+ return semver.Version{}, "", fmt.Errorf("Error scanning version string on %q: %v", server, err)
}
+ semanticVersion, err := parseVersion(versionString)
if err != nil {
- return []prometheus.Metric{}, []error{}, fmt.Errorf("Error running query on database %q: %s %v", server, namespace, err)
- }
- defer rows.Close() // nolint: errcheck
-
- var columnNames []string
- columnNames, err = rows.Columns()
- if err != nil {
- return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving column list for: ", namespace, err))
+ return semver.Version{}, "", fmt.Errorf("Error parsing version string on %q: %v", server, err)
}
- // Make a lookup map for the column indices
- var columnIdx = make(map[string]int, len(columnNames))
- for i, n := range columnNames {
- columnIdx[n] = i
- }
-
- var columnData = make([]interface{}, len(columnNames))
- var scanArgs = make([]interface{}, len(columnNames))
- for i := range columnData {
- scanArgs[i] = &columnData[i]
- }
-
- nonfatalErrors := []error{}
-
- metrics := make([]prometheus.Metric, 0)
-
- for rows.Next() {
- err = rows.Scan(scanArgs...)
- if err != nil {
- return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving rows:", namespace, err))
- }
-
- // Get the label values for this row.
- labels := make([]string, len(mapping.labels))
- for idx, label := range mapping.labels {
- labels[idx], _ = dbToString(columnData[columnIdx[label]])
- }
-
- // Loop over column names, and match to scan data. Unknown columns
- // will be filled with an untyped metric number *if* they can be
- // converted to float64s. NULLs are allowed and treated as NaN.
- for idx, columnName := range columnNames {
- var metric prometheus.Metric
- if metricMapping, ok := mapping.columnMappings[columnName]; ok {
- // Is this a metricy metric?
- if metricMapping.discard {
- continue
- }
-
- if metricMapping.histogram {
- var keys []float64
- err = pq.Array(&keys).Scan(columnData[idx])
- if err != nil {
- return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving", columnName, "buckets:", namespace, err))
- }
-
- var values []int64
- valuesIdx, ok := columnIdx[columnName+"_bucket"]
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Missing column: ", namespace, columnName+"_bucket")))
- continue
- }
- err = pq.Array(&values).Scan(columnData[valuesIdx])
- if err != nil {
- return []prometheus.Metric{}, []error{}, errors.New(fmt.Sprintln("Error retrieving", columnName, "bucket values:", namespace, err))
- }
-
- buckets := make(map[float64]uint64, len(keys))
- for i, key := range keys {
- if i >= len(values) {
- break
- }
- buckets[key] = uint64(values[i])
- }
-
- idx, ok = columnIdx[columnName+"_sum"]
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Missing column: ", namespace, columnName+"_sum")))
- continue
- }
- sum, ok := dbToFloat64(columnData[idx])
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unexpected error parsing column: ", namespace, columnName+"_sum", columnData[idx])))
- continue
- }
-
- idx, ok = columnIdx[columnName+"_count"]
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Missing column: ", namespace, columnName+"_count")))
- continue
- }
- count, ok := dbToUint64(columnData[idx])
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unexpected error parsing column: ", namespace, columnName+"_count", columnData[idx])))
- continue
- }
-
- metric = prometheus.MustNewConstHistogram(
- metricMapping.desc,
- count, sum, buckets,
- labels...,
- )
- } else {
- value, ok := dbToFloat64(columnData[idx])
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unexpected error parsing column: ", namespace, columnName, columnData[idx])))
- continue
- }
- // Generate the metric
- metric = prometheus.MustNewConstMetric(metricMapping.desc, metricMapping.vtype, value, labels...)
- }
- } else {
- // Unknown metric. Report as untyped if scan to float64 works, else note an error too.
- metricLabel := fmt.Sprintf("%s_%s", namespace, columnName)
- desc := prometheus.NewDesc(metricLabel, fmt.Sprintf("Unknown metric from %s", namespace), mapping.labels, server.labels)
-
- // Its not an error to fail here, since the values are
- // unexpected anyway.
- value, ok := dbToFloat64(columnData[idx])
- if !ok {
- nonfatalErrors = append(nonfatalErrors, errors.New(fmt.Sprintln("Unparseable column type - discarding: ", namespace, columnName, err)))
- continue
- }
- metric = prometheus.MustNewConstMetric(desc, prometheus.UntypedValue, value, labels...)
- }
- metrics = append(metrics, metric)
- }
- }
- return metrics, nonfatalErrors, nil
-}
-
-// Iterate through all the namespace mappings in the exporter and run their
-// queries.
-func queryNamespaceMappings(ch chan<- prometheus.Metric, server *Server) map[string]error {
- // Return a map of namespace -> errors
- namespaceErrors := make(map[string]error)
-
- scrapeStart := time.Now()
-
- for namespace, mapping := range server.metricMap {
- level.Debug(logger).Log("msg", "Querying namespace", "namespace", namespace)
-
- if mapping.master && !server.master {
- level.Debug(logger).Log("msg", "Query skipped...")
- continue
- }
-
- // check if the query is to be run on specific database server version range or not
- if len(server.runonserver) > 0 {
- serVersion, _ := semver.Parse(server.lastMapVersion.String())
- runServerRange, _ := semver.ParseRange(server.runonserver)
- if !runServerRange(serVersion) {
- level.Debug(logger).Log("msg", "Query skipped for this database version", "version", server.lastMapVersion.String(), "target_version", server.runonserver)
- continue
- }
- }
-
- scrapeMetric := false
- // Check if the metric is cached
- server.cacheMtx.Lock()
- cachedMetric, found := server.metricCache[namespace]
- server.cacheMtx.Unlock()
- // If found, check if needs refresh from cache
- if found {
- if scrapeStart.Sub(cachedMetric.lastScrape).Seconds() > float64(mapping.cacheSeconds) {
- scrapeMetric = true
- }
- } else {
- scrapeMetric = true
- }
-
- var metrics []prometheus.Metric
- var nonFatalErrors []error
- var err error
- if scrapeMetric {
- metrics, nonFatalErrors, err = queryNamespaceMapping(server, namespace, mapping)
- } else {
- metrics = cachedMetric.metrics
- }
-
- // Serious error - a namespace disappeared
- if err != nil {
- namespaceErrors[namespace] = err
- level.Info(logger).Log("err", err)
- }
- // Non-serious errors - likely version or parsing problems.
- if len(nonFatalErrors) > 0 {
- for _, err := range nonFatalErrors {
- level.Info(logger).Log("err", err)
- }
- }
-
- // Emit the metrics into the channel
- for _, metric := range metrics {
- ch <- metric
- }
-
- if scrapeMetric {
- // Only cache if metric is meaningfully cacheable
- if mapping.cacheSeconds > 0 {
- server.cacheMtx.Lock()
- server.metricCache[namespace] = cachedMetrics{
- metrics: metrics,
- lastScrape: scrapeStart,
- }
- server.cacheMtx.Unlock()
- }
- }
- }
-
- return namespaceErrors
+ return semanticVersion, versionString, nil
}
// Check and update the exporters query maps if the version has changed.
func (e *Exporter) checkMapVersions(ch chan<- prometheus.Metric, server *Server) error {
- level.Debug(logger).Log("msg", "Querying PostgreSQL version", "server", server)
- versionRow := server.db.QueryRow("SELECT version();")
- var versionString string
- err := versionRow.Scan(&versionString)
+ semanticVersion, versionString, err := checkPostgresVersion(server.db, server.String())
if err != nil {
- return fmt.Errorf("Error scanning version string on %q: %v", server, err)
- }
- semanticVersion, err := parseVersion(versionString)
- if err != nil {
- return fmt.Errorf("Error parsing version string on %q: %v", server, err)
+ return fmt.Errorf("Error fetching version string on %q: %v", server, err)
}
+
if !e.disableDefaultMetrics && semanticVersion.LT(lowestSupportedVersion) {
level.Warn(logger).Log("msg", "PostgreSQL version is lower than our lowest supported version", "server", server, "version", semanticVersion, "lowest_supported_version", lowestSupportedVersion)
}
@@ -1650,222 +750,3 @@ func (e *Exporter) scrape(ch chan<- prometheus.Metric) {
e.error.Set(1)
}
}
-
-func (e *Exporter) discoverDatabaseDSNs() []string {
- // connstring syntax is complex (and not sure if even regular).
- // we don't need to parse it, so just superficially validate that it starts
- // with a valid-ish keyword pair
- connstringRe := regexp.MustCompile(`^ *[a-zA-Z0-9]+ *= *[^= ]+`)
-
- dsns := make(map[string]struct{})
- for _, dsn := range e.dsn {
- var dsnURI *url.URL
- var dsnConnstring string
-
- if strings.HasPrefix(dsn, "postgresql://") {
- var err error
- dsnURI, err = url.Parse(dsn)
- if err != nil {
- level.Error(logger).Log("msg", "Unable to parse DSN as URI", "dsn", loggableDSN(dsn), "err", err)
- continue
- }
- } else if connstringRe.MatchString(dsn) {
- dsnConnstring = dsn
- } else {
- level.Error(logger).Log("msg", "Unable to parse DSN as either URI or connstring", "dsn", loggableDSN(dsn))
- continue
- }
-
- server, err := e.servers.GetServer(dsn)
- if err != nil {
- level.Error(logger).Log("msg", "Error opening connection to database", "dsn", loggableDSN(dsn), "err", err)
- continue
- }
- dsns[dsn] = struct{}{}
-
- // If autoDiscoverDatabases is true, set first dsn as master database (Default: false)
- server.master = true
-
- databaseNames, err := queryDatabases(server)
- if err != nil {
- level.Error(logger).Log("msg", "Error querying databases", "dsn", loggableDSN(dsn), "err", err)
- continue
- }
- for _, databaseName := range databaseNames {
- if contains(e.excludeDatabases, databaseName) {
- continue
- }
-
- if len(e.includeDatabases) != 0 && !contains(e.includeDatabases, databaseName) {
- continue
- }
-
- if dsnURI != nil {
- dsnURI.Path = databaseName
- dsn = dsnURI.String()
- } else {
- // replacing one dbname with another is complicated.
- // just append new dbname to override.
- dsn = fmt.Sprintf("%s dbname=%s", dsnConnstring, databaseName)
- }
- dsns[dsn] = struct{}{}
- }
- }
-
- result := make([]string, len(dsns))
- index := 0
- for dsn := range dsns {
- result[index] = dsn
- index++
- }
-
- return result
-}
-
-func (e *Exporter) scrapeDSN(ch chan<- prometheus.Metric, dsn string) error {
- server, err := e.servers.GetServer(dsn)
-
- if err != nil {
- return &ErrorConnectToServer{fmt.Sprintf("Error opening connection to database (%s): %s", loggableDSN(dsn), err.Error())}
- }
-
- // Check if autoDiscoverDatabases is false, set dsn as master database (Default: false)
- if !e.autoDiscoverDatabases {
- server.master = true
- }
-
- // Check if map versions need to be updated
- if err := e.checkMapVersions(ch, server); err != nil {
- level.Warn(logger).Log("msg", "Proceeding with outdated query maps, as the Postgres version could not be determined", "err", err)
- }
-
- return server.Scrape(ch, e.disableSettingsMetrics)
-}
-
-// try to get the DataSource
-// DATA_SOURCE_NAME always wins so we do not break older versions
-// reading secrets from files wins over secrets in environment variables
-// DATA_SOURCE_NAME > DATA_SOURCE_{USER|PASS}_FILE > DATA_SOURCE_{USER|PASS}
-func getDataSources() ([]string, error) {
- var dsn = os.Getenv("DATA_SOURCE_NAME")
- if len(dsn) != 0 {
- return strings.Split(dsn, ","), nil
- }
-
- var user, pass, uri string
-
- dataSourceUserFile := os.Getenv("DATA_SOURCE_USER_FILE")
- if len(dataSourceUserFile) != 0 {
- fileContents, err := ioutil.ReadFile(dataSourceUserFile)
- if err != nil {
- return nil, fmt.Errorf("failed loading data source user file %s: %s", dataSourceUserFile, err.Error())
- }
- user = strings.TrimSpace(string(fileContents))
- } else {
- user = os.Getenv("DATA_SOURCE_USER")
- }
-
- dataSourcePassFile := os.Getenv("DATA_SOURCE_PASS_FILE")
- if len(dataSourcePassFile) != 0 {
- fileContents, err := ioutil.ReadFile(dataSourcePassFile)
- if err != nil {
- return nil, fmt.Errorf("failed loading data source pass file %s: %s", dataSourcePassFile, err.Error())
- }
- pass = strings.TrimSpace(string(fileContents))
- } else {
- pass = os.Getenv("DATA_SOURCE_PASS")
- }
-
- ui := url.UserPassword(user, pass).String()
- dataSrouceURIFile := os.Getenv("DATA_SOURCE_URI_FILE")
- if len(dataSrouceURIFile) != 0 {
- fileContents, err := ioutil.ReadFile(dataSrouceURIFile)
- if err != nil {
- return nil, fmt.Errorf("failed loading data source URI file %s: %s", dataSrouceURIFile, err.Error())
- }
- uri = strings.TrimSpace(string(fileContents))
- } else {
- uri = os.Getenv("DATA_SOURCE_URI")
- }
-
- dsn = "postgresql://" + ui + "@" + uri
-
- return []string{dsn}, nil
-}
-
-func contains(a []string, x string) bool {
- for _, n := range a {
- if x == n {
- return true
- }
- }
- return false
-}
-
-func main() {
- kingpin.Version(version.Print(exporterName))
- promlogConfig := &promlog.Config{}
- flag.AddFlags(kingpin.CommandLine, promlogConfig)
- kingpin.HelpFlag.Short('h')
- kingpin.Parse()
- logger = promlog.New(promlogConfig)
-
- // landingPage contains the HTML served at '/'.
- // TODO: Make this nicer and more informative.
- var landingPage = []byte(`
- Postgres exporter
-
- Postgres exporter
- Metrics
-
-
- `)
-
- if *onlyDumpMaps {
- dumpMaps()
- return
- }
-
- dsn, err := getDataSources()
- if err != nil {
- level.Error(logger).Log("msg", "Failed reading data sources", "err", err.Error())
- os.Exit(1)
- }
-
- if len(dsn) == 0 {
- level.Error(logger).Log("msg", "Couldn't find environment variables describing the datasource to use")
- os.Exit(1)
- }
-
- opts := []ExporterOpt{
- DisableDefaultMetrics(*disableDefaultMetrics),
- DisableSettingsMetrics(*disableSettingsMetrics),
- AutoDiscoverDatabases(*autoDiscoverDatabases),
- WithUserQueriesPath(*queriesPath),
- WithConstantLabels(*constantLabelsList),
- ExcludeDatabases(*excludeDatabases),
- IncludeDatabases(*includeDatabases),
- }
-
- exporter := NewExporter(dsn, opts...)
- defer func() {
- exporter.servers.Close()
- }()
-
- prometheus.MustRegister(version.NewCollector(exporterName))
-
- prometheus.MustRegister(exporter)
-
- http.Handle(*metricPath, promhttp.Handler())
- http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
- w.Header().Set("Content-Type", "text/html; charset=UTF-8") // nolint: errcheck
- w.Write(landingPage) // nolint: errcheck
- })
-
- level.Info(logger).Log("msg", "Listening on address", "address", *listenAddress)
- srv := &http.Server{Addr: *listenAddress}
- if err := web.ListenAndServe(srv, *webConfig, logger); err != nil {
- level.Error(logger).Log("msg", "Error running HTTP server", "err", err)
- os.Exit(1)
- }
-}
diff --git a/cmd/postgres_exporter/queries.go b/cmd/postgres_exporter/queries.go
new file mode 100644
index 00000000..903e1a27
--- /dev/null
+++ b/cmd/postgres_exporter/queries.go
@@ -0,0 +1,303 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "errors"
+ "fmt"
+
+ "github.com/blang/semver"
+ "github.com/go-kit/kit/log/level"
+ "gopkg.in/yaml.v2"
+)
+
+// UserQuery represents a user defined query
+type UserQuery struct {
+ Query string `yaml:"query"`
+ Metrics []Mapping `yaml:"metrics"`
+ Master bool `yaml:"master"` // Querying only for master database
+ CacheSeconds uint64 `yaml:"cache_seconds"` // Number of seconds to cache the namespace result metrics for.
+ RunOnServer string `yaml:"runonserver"` // Querying to run on which server version
+}
+
+// UserQueries represents a set of UserQuery objects
+type UserQueries map[string]UserQuery
+
+// OverrideQuery 's are run in-place of simple namespace look ups, and provide
+// advanced functionality. But they have a tendency to postgres version specific.
+// There aren't too many versions, so we simply store customized versions using
+// the semver matching we do for columns.
+type OverrideQuery struct {
+ versionRange semver.Range
+ query string
+}
+
+// Overriding queries for namespaces above.
+// TODO: validate this is a closed set in tests, and there are no overlaps
+var queryOverrides = map[string][]OverrideQuery{
+ "pg_locks": {
+ {
+ semver.MustParseRange(">0.0.0"),
+ `SELECT pg_database.datname,tmp.mode,COALESCE(count,0) as count
+ FROM
+ (
+ VALUES ('accesssharelock'),
+ ('rowsharelock'),
+ ('rowexclusivelock'),
+ ('shareupdateexclusivelock'),
+ ('sharelock'),
+ ('sharerowexclusivelock'),
+ ('exclusivelock'),
+ ('accessexclusivelock'),
+ ('sireadlock')
+ ) AS tmp(mode) CROSS JOIN pg_database
+ LEFT JOIN
+ (SELECT database, lower(mode) AS mode,count(*) AS count
+ FROM pg_locks WHERE database IS NOT NULL
+ GROUP BY database, lower(mode)
+ ) AS tmp2
+ ON tmp.mode=tmp2.mode and pg_database.oid = tmp2.database ORDER BY 1`,
+ },
+ },
+
+ "pg_stat_replication": {
+ {
+ semver.MustParseRange(">=10.0.0"),
+ `
+ SELECT *,
+ (case pg_is_in_recovery() when 't' then null else pg_current_wal_lsn() end) AS pg_current_wal_lsn,
+ (case pg_is_in_recovery() when 't' then null else pg_wal_lsn_diff(pg_current_wal_lsn(), pg_lsn('0/0'))::float end) AS pg_current_wal_lsn_bytes,
+ (case pg_is_in_recovery() when 't' then null else pg_wal_lsn_diff(pg_current_wal_lsn(), replay_lsn)::float end) AS pg_wal_lsn_diff
+ FROM pg_stat_replication
+ `,
+ },
+ {
+ semver.MustParseRange(">=9.2.0 <10.0.0"),
+ `
+ SELECT *,
+ (case pg_is_in_recovery() when 't' then null else pg_current_xlog_location() end) AS pg_current_xlog_location,
+ (case pg_is_in_recovery() when 't' then null else pg_xlog_location_diff(pg_current_xlog_location(), replay_location)::float end) AS pg_xlog_location_diff
+ FROM pg_stat_replication
+ `,
+ },
+ {
+ semver.MustParseRange("<9.2.0"),
+ `
+ SELECT *,
+ (case pg_is_in_recovery() when 't' then null else pg_current_xlog_location() end) AS pg_current_xlog_location
+ FROM pg_stat_replication
+ `,
+ },
+ },
+
+ "pg_replication_slots": {
+ {
+ semver.MustParseRange(">=9.4.0 <10.0.0"),
+ `
+ SELECT slot_name, database, active, pg_xlog_location_diff(pg_current_xlog_location(), restart_lsn)
+ FROM pg_replication_slots
+ `,
+ },
+ {
+ semver.MustParseRange(">=10.0.0"),
+ `
+ SELECT slot_name, database, active, pg_wal_lsn_diff(pg_current_wal_lsn(), restart_lsn)
+ FROM pg_replication_slots
+ `,
+ },
+ },
+
+ "pg_stat_archiver": {
+ {
+ semver.MustParseRange(">=0.0.0"),
+ `
+ SELECT *,
+ extract(epoch from now() - last_archived_time) AS last_archive_age
+ FROM pg_stat_archiver
+ `,
+ },
+ },
+
+ "pg_stat_activity": {
+ // This query only works
+ {
+ semver.MustParseRange(">=9.2.0"),
+ `
+ SELECT
+ pg_database.datname,
+ tmp.state,
+ COALESCE(count,0) as count,
+ COALESCE(max_tx_duration,0) as max_tx_duration
+ FROM
+ (
+ VALUES ('active'),
+ ('idle'),
+ ('idle in transaction'),
+ ('idle in transaction (aborted)'),
+ ('fastpath function call'),
+ ('disabled')
+ ) AS tmp(state) CROSS JOIN pg_database
+ LEFT JOIN
+ (
+ SELECT
+ datname,
+ state,
+ count(*) AS count,
+ MAX(EXTRACT(EPOCH FROM now() - xact_start))::float AS max_tx_duration
+ FROM pg_stat_activity GROUP BY datname,state) AS tmp2
+ ON tmp.state = tmp2.state AND pg_database.datname = tmp2.datname
+ `,
+ },
+ {
+ semver.MustParseRange("<9.2.0"),
+ `
+ SELECT
+ datname,
+ 'unknown' AS state,
+ COALESCE(count(*),0) AS count,
+ COALESCE(MAX(EXTRACT(EPOCH FROM now() - xact_start))::float,0) AS max_tx_duration
+ FROM pg_stat_activity GROUP BY datname
+ `,
+ },
+ },
+}
+
+// Convert the query override file to the version-specific query override file
+// for the exporter.
+func makeQueryOverrideMap(pgVersion semver.Version, queryOverrides map[string][]OverrideQuery) map[string]string {
+ resultMap := make(map[string]string)
+ for name, overrideDef := range queryOverrides {
+ // Find a matching semver. We make it an error to have overlapping
+ // ranges at test-time, so only 1 should ever match.
+ matched := false
+ for _, queryDef := range overrideDef {
+ if queryDef.versionRange(pgVersion) {
+ resultMap[name] = queryDef.query
+ matched = true
+ break
+ }
+ }
+ if !matched {
+ level.Warn(logger).Log("msg", "No query matched override, disabling metric space", "name", name)
+ resultMap[name] = ""
+ }
+ }
+
+ return resultMap
+}
+
+func parseUserQueries(content []byte) (map[string]intermediateMetricMap, map[string]string, error) {
+ var userQueries UserQueries
+
+ err := yaml.Unmarshal(content, &userQueries)
+ if err != nil {
+ return nil, nil, err
+ }
+
+ // Stores the loaded map representation
+ metricMaps := make(map[string]intermediateMetricMap)
+ newQueryOverrides := make(map[string]string)
+
+ for metric, specs := range userQueries {
+ level.Debug(logger).Log("msg", "New user metric namespace from YAML metric", "metric", metric, "cache_seconds", specs.CacheSeconds)
+ newQueryOverrides[metric] = specs.Query
+ metricMap, ok := metricMaps[metric]
+ if !ok {
+ // Namespace for metric not found - add it.
+ newMetricMap := make(map[string]ColumnMapping)
+ metricMap = intermediateMetricMap{
+ columnMappings: newMetricMap,
+ master: specs.Master,
+ cacheSeconds: specs.CacheSeconds,
+ }
+ metricMaps[metric] = metricMap
+ }
+ for _, metric := range specs.Metrics {
+ for name, mappingOption := range metric {
+ var columnMapping ColumnMapping
+ tmpUsage, _ := stringToColumnUsage(mappingOption.Usage)
+ columnMapping.usage = tmpUsage
+ columnMapping.description = mappingOption.Description
+
+ // TODO: we should support cu
+ columnMapping.mapping = nil
+ // Should we support this for users?
+ columnMapping.supportedVersions = nil
+
+ metricMap.columnMappings[name] = columnMapping
+ }
+ }
+ }
+ return metricMaps, newQueryOverrides, nil
+}
+
+// Add queries to the builtinMetricMaps and queryOverrides maps. Added queries do not
+// respect version requirements, because it is assumed that the user knows
+// what they are doing with their version of postgres.
+//
+// This function modifies metricMap and queryOverrideMap to contain the new
+// queries.
+// TODO: test code for all cu.
+// TODO: the YAML this supports is "non-standard" - we should move away from it.
+func addQueries(content []byte, pgVersion semver.Version, server *Server) error {
+ metricMaps, newQueryOverrides, err := parseUserQueries(content)
+ if err != nil {
+ return err
+ }
+ // Convert the loaded metric map into exporter representation
+ partialExporterMap := makeDescMap(pgVersion, server.labels, metricMaps)
+
+ // Merge the two maps (which are now quite flatteend)
+ for k, v := range partialExporterMap {
+ _, found := server.metricMap[k]
+ if found {
+ level.Debug(logger).Log("msg", "Overriding metric from user YAML file", "metric", k)
+ } else {
+ level.Debug(logger).Log("msg", "Adding new metric from user YAML file", "metric", k)
+ }
+ server.metricMap[k] = v
+ }
+
+ // Merge the query override map
+ for k, v := range newQueryOverrides {
+ _, found := server.queryOverrides[k]
+ if found {
+ level.Debug(logger).Log("msg", "Overriding query override from user YAML file", "query_override", k)
+ } else {
+ level.Debug(logger).Log("msg", "Adding new query override from user YAML file", "query_override", k)
+ }
+ server.queryOverrides[k] = v
+ }
+ return nil
+}
+
+func queryDatabases(server *Server) ([]string, error) {
+ rows, err := server.db.Query("SELECT datname FROM pg_database WHERE datallowconn = true AND datistemplate = false AND datname != current_database()")
+ if err != nil {
+ return nil, fmt.Errorf("Error retrieving databases: %v", err)
+ }
+ defer rows.Close() // nolint: errcheck
+
+ var databaseName string
+ result := make([]string, 0)
+ for rows.Next() {
+ err = rows.Scan(&databaseName)
+ if err != nil {
+ return nil, errors.New(fmt.Sprintln("Error retrieving rows:", err))
+ }
+ result = append(result, databaseName)
+ }
+
+ return result, nil
+}
diff --git a/cmd/postgres_exporter/server.go b/cmd/postgres_exporter/server.go
new file mode 100644
index 00000000..cf2469cc
--- /dev/null
+++ b/cmd/postgres_exporter/server.go
@@ -0,0 +1,190 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "database/sql"
+ "fmt"
+ "sync"
+ "time"
+
+ "github.com/blang/semver"
+ "github.com/go-kit/kit/log/level"
+ "github.com/prometheus/client_golang/prometheus"
+)
+
+// Server describes a connection to Postgres.
+// Also it contains metrics map and query overrides.
+type Server struct {
+ db *sql.DB
+ labels prometheus.Labels
+ master bool
+ runonserver string
+
+ // Last version used to calculate metric map. If mismatch on scrape,
+ // then maps are recalculated.
+ lastMapVersion semver.Version
+ // Currently active metric map
+ metricMap map[string]MetricMapNamespace
+ // Currently active query overrides
+ queryOverrides map[string]string
+ mappingMtx sync.RWMutex
+ // Currently cached metrics
+ metricCache map[string]cachedMetrics
+ cacheMtx sync.Mutex
+}
+
+// ServerOpt configures a server.
+type ServerOpt func(*Server)
+
+// ServerWithLabels configures a set of labels.
+func ServerWithLabels(labels prometheus.Labels) ServerOpt {
+ return func(s *Server) {
+ for k, v := range labels {
+ s.labels[k] = v
+ }
+ }
+}
+
+// NewServer establishes a new connection using DSN.
+func NewServer(dsn string, opts ...ServerOpt) (*Server, error) {
+ fingerprint, err := parseFingerprint(dsn)
+ if err != nil {
+ return nil, err
+ }
+
+ db, err := sql.Open("postgres", dsn)
+ if err != nil {
+ return nil, err
+ }
+ db.SetMaxOpenConns(1)
+ db.SetMaxIdleConns(1)
+
+ level.Info(logger).Log("msg", "Established new database connection", "fingerprint", fingerprint)
+
+ s := &Server{
+ db: db,
+ master: false,
+ labels: prometheus.Labels{
+ serverLabelName: fingerprint,
+ },
+ metricCache: make(map[string]cachedMetrics),
+ }
+
+ for _, opt := range opts {
+ opt(s)
+ }
+
+ return s, nil
+}
+
+// Close disconnects from Postgres.
+func (s *Server) Close() error {
+ return s.db.Close()
+}
+
+// Ping checks connection availability and possibly invalidates the connection if it fails.
+func (s *Server) Ping() error {
+ if err := s.db.Ping(); err != nil {
+ if cerr := s.Close(); cerr != nil {
+ level.Error(logger).Log("msg", "Error while closing non-pinging DB connection", "server", s, "err", cerr)
+ }
+ return err
+ }
+ return nil
+}
+
+// String returns server's fingerprint.
+func (s *Server) String() string {
+ return s.labels[serverLabelName]
+}
+
+// Scrape loads metrics.
+func (s *Server) Scrape(ch chan<- prometheus.Metric, disableSettingsMetrics bool) error {
+ s.mappingMtx.RLock()
+ defer s.mappingMtx.RUnlock()
+
+ var err error
+
+ if !disableSettingsMetrics && s.master {
+ if err = querySettings(ch, s); err != nil {
+ err = fmt.Errorf("error retrieving settings: %s", err)
+ }
+ }
+
+ errMap := queryNamespaceMappings(ch, s)
+ if len(errMap) > 0 {
+ err = fmt.Errorf("queryNamespaceMappings returned %d errors", len(errMap))
+ }
+
+ return err
+}
+
+// Servers contains a collection of servers to Postgres.
+type Servers struct {
+ m sync.Mutex
+ servers map[string]*Server
+ opts []ServerOpt
+}
+
+// NewServers creates a collection of servers to Postgres.
+func NewServers(opts ...ServerOpt) *Servers {
+ return &Servers{
+ servers: make(map[string]*Server),
+ opts: opts,
+ }
+}
+
+// GetServer returns established connection from a collection.
+func (s *Servers) GetServer(dsn string) (*Server, error) {
+ s.m.Lock()
+ defer s.m.Unlock()
+ var err error
+ var ok bool
+ errCount := 0 // start at zero because we increment before doing work
+ retries := 1
+ var server *Server
+ for {
+ if errCount++; errCount > retries {
+ return nil, err
+ }
+ server, ok = s.servers[dsn]
+ if !ok {
+ server, err = NewServer(dsn, s.opts...)
+ if err != nil {
+ time.Sleep(time.Duration(errCount) * time.Second)
+ continue
+ }
+ s.servers[dsn] = server
+ }
+ if err = server.Ping(); err != nil {
+ delete(s.servers, dsn)
+ time.Sleep(time.Duration(errCount) * time.Second)
+ continue
+ }
+ break
+ }
+ return server, nil
+}
+
+// Close disconnects from all known servers.
+func (s *Servers) Close() {
+ s.m.Lock()
+ defer s.m.Unlock()
+ for _, server := range s.servers {
+ if err := server.Close(); err != nil {
+ level.Error(logger).Log("msg", "Failed to close connection", "server", server, "err", err)
+ }
+ }
+}
diff --git a/cmd/postgres_exporter/util.go b/cmd/postgres_exporter/util.go
new file mode 100644
index 00000000..5ecb5ec7
--- /dev/null
+++ b/cmd/postgres_exporter/util.go
@@ -0,0 +1,218 @@
+// Copyright 2021 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+ "fmt"
+ "math"
+ "net/url"
+ "strconv"
+ "strings"
+ "time"
+
+ "github.com/go-kit/kit/log/level"
+ "github.com/lib/pq"
+)
+
+func contains(a []string, x string) bool {
+ for _, n := range a {
+ if x == n {
+ return true
+ }
+ }
+ return false
+}
+
+// convert a string to the corresponding ColumnUsage
+func stringToColumnUsage(s string) (ColumnUsage, error) {
+ var u ColumnUsage
+ var err error
+ switch s {
+ case "DISCARD":
+ u = DISCARD
+
+ case "LABEL":
+ u = LABEL
+
+ case "COUNTER":
+ u = COUNTER
+
+ case "GAUGE":
+ u = GAUGE
+
+ case "HISTOGRAM":
+ u = HISTOGRAM
+
+ case "MAPPEDMETRIC":
+ u = MAPPEDMETRIC
+
+ case "DURATION":
+ u = DURATION
+
+ default:
+ err = fmt.Errorf("wrong ColumnUsage given : %s", s)
+ }
+
+ return u, err
+}
+
+// Convert database.sql types to float64s for Prometheus consumption. Null types are mapped to NaN. string and []byte
+// types are mapped as NaN and !ok
+func dbToFloat64(t interface{}) (float64, bool) {
+ switch v := t.(type) {
+ case int64:
+ return float64(v), true
+ case float64:
+ return v, true
+ case time.Time:
+ return float64(v.Unix()), true
+ case []byte:
+ // Try and convert to string and then parse to a float64
+ strV := string(v)
+ result, err := strconv.ParseFloat(strV, 64)
+ if err != nil {
+ level.Info(logger).Log("msg", "Could not parse []byte", "err", err)
+ return math.NaN(), false
+ }
+ return result, true
+ case string:
+ result, err := strconv.ParseFloat(v, 64)
+ if err != nil {
+ level.Info(logger).Log("msg", "Could not parse string", "err", err)
+ return math.NaN(), false
+ }
+ return result, true
+ case bool:
+ if v {
+ return 1.0, true
+ }
+ return 0.0, true
+ case nil:
+ return math.NaN(), true
+ default:
+ return math.NaN(), false
+ }
+}
+
+// Convert database.sql types to uint64 for Prometheus consumption. Null types are mapped to 0. string and []byte
+// types are mapped as 0 and !ok
+func dbToUint64(t interface{}) (uint64, bool) {
+ switch v := t.(type) {
+ case uint64:
+ return v, true
+ case int64:
+ return uint64(v), true
+ case float64:
+ return uint64(v), true
+ case time.Time:
+ return uint64(v.Unix()), true
+ case []byte:
+ // Try and convert to string and then parse to a uint64
+ strV := string(v)
+ result, err := strconv.ParseUint(strV, 10, 64)
+ if err != nil {
+ level.Info(logger).Log("msg", "Could not parse []byte", "err", err)
+ return 0, false
+ }
+ return result, true
+ case string:
+ result, err := strconv.ParseUint(v, 10, 64)
+ if err != nil {
+ level.Info(logger).Log("msg", "Could not parse string", "err", err)
+ return 0, false
+ }
+ return result, true
+ case bool:
+ if v {
+ return 1, true
+ }
+ return 0, true
+ case nil:
+ return 0, true
+ default:
+ return 0, false
+ }
+}
+
+// Convert database.sql to string for Prometheus labels. Null types are mapped to empty strings.
+func dbToString(t interface{}) (string, bool) {
+ switch v := t.(type) {
+ case int64:
+ return fmt.Sprintf("%v", v), true
+ case float64:
+ return fmt.Sprintf("%v", v), true
+ case time.Time:
+ return fmt.Sprintf("%v", v.Unix()), true
+ case nil:
+ return "", true
+ case []byte:
+ // Try and convert to string
+ return string(v), true
+ case string:
+ return v, true
+ case bool:
+ if v {
+ return "true", true
+ }
+ return "false", true
+ default:
+ return "", false
+ }
+}
+
+func parseFingerprint(url string) (string, error) {
+ dsn, err := pq.ParseURL(url)
+ if err != nil {
+ dsn = url
+ }
+
+ pairs := strings.Split(dsn, " ")
+ kv := make(map[string]string, len(pairs))
+ for _, pair := range pairs {
+ splitted := strings.SplitN(pair, "=", 2)
+ if len(splitted) != 2 {
+ return "", fmt.Errorf("malformed dsn %q", dsn)
+ }
+ kv[splitted[0]] = splitted[1]
+ }
+
+ var fingerprint string
+
+ if host, ok := kv["host"]; ok {
+ fingerprint += host
+ } else {
+ fingerprint += "localhost"
+ }
+
+ if port, ok := kv["port"]; ok {
+ fingerprint += ":" + port
+ } else {
+ fingerprint += ":5432"
+ }
+
+ return fingerprint, nil
+}
+
+func loggableDSN(dsn string) string {
+ pDSN, err := url.Parse(dsn)
+ if err != nil {
+ return "could not parse DATA_SOURCE_NAME"
+ }
+ // Blank user info if not nil
+ if pDSN.User != nil {
+ pDSN.User = url.UserPassword(pDSN.User.Username(), "PASSWORD_REMOVED")
+ }
+
+ return pDSN.String()
+}