postgres_exporter/collector/server.go
Joe Adams c3b0206369
Add collector interface
Uses node_exporter style collector registration

Signed-off-by: Joe Adams <github@joeadams.io>
2022-02-14 21:12:27 -05:00

101 lines
2.0 KiB
Go

// Copyright 2022 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 collector
import (
"database/sql"
"fmt"
"strings"
"github.com/lib/pq"
)
type server struct {
dsn string
name string
db *sql.DB
}
func makeServer(dsn string) (*server, error) {
name, err := parseServerName(dsn)
if err != nil {
return nil, err
}
return &server{
dsn: dsn,
name: name,
}, nil
}
func (s *server) GetDB() (*sql.DB, error) {
if s.db != nil {
return s.db, nil
}
db, err := sql.Open("postgres", s.dsn)
if err != nil {
return nil, err
}
db.SetMaxOpenConns(1)
db.SetMaxIdleConns(1)
s.db = db
return s.db, nil
}
func (s *server) GetName() string {
return s.name
}
func (s *server) String() string {
return s.name
}
func parseServerName(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)
}
// Newer versions of pq.ParseURL quote values so trim them off if they exist
key := strings.Trim(splitted[0], "'\"")
value := strings.Trim(splitted[1], "'\"")
kv[key] = value
}
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
}