package config import ( "encoding/json" "fmt" "io/ioutil" "regexp" "strings" "time" "gopkg.in/yaml.v2" clientmodel "github.com/prometheus/client_golang/model" "github.com/prometheus/prometheus/util/strutil" ) var ( patJobName = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_-]*$`) patFileSDName = regexp.MustCompile(`^[^*]*(\*[^/]*)?\.(json|yml|yaml|JSON|YML|YAML)$`) patRulePath = regexp.MustCompile(`^[^*]*(\*[^/]*)?$`) ) // Load parses the YAML input s into a Config. func Load(s string) (*Config, error) { cfg := &Config{ original: s, } err := yaml.Unmarshal([]byte(s), cfg) if err != nil { return nil, err } return cfg, nil } // LoadFromFile parses the given YAML file into a Config. func LoadFromFile(filename string) (*Config, error) { content, err := ioutil.ReadFile(filename) if err != nil { return nil, err } return Load(string(content)) } // The defaults applied before parsing the respective config sections. var ( // The default top-level configuration. DefaultConfig = Config{ GlobalConfig: DefaultGlobalConfig, } // The default global configuration. DefaultGlobalConfig = GlobalConfig{ ScrapeInterval: Duration(1 * time.Minute), ScrapeTimeout: Duration(10 * time.Second), EvaluationInterval: Duration(1 * time.Minute), } // The default scrape configuration. DefaultScrapeConfig = ScrapeConfig{ // ScrapeTimeout and ScrapeInterval default to the // configured globals. MetricsPath: "/metrics", Scheme: "http", } // The default Relabel configuration. DefaultRelabelConfig = RelabelConfig{ Action: RelabelReplace, Separator: ";", } // The default DNS SD configuration. DefaultDNSSDConfig = DNSSDConfig{ RefreshInterval: Duration(30 * time.Second), } // The default file SD configuration. DefaultFileSDConfig = FileSDConfig{ RefreshInterval: Duration(30 * time.Second), } // The default Consul SD configuration. DefaultConsulSDConfig = ConsulSDConfig{ TagSeparator: ",", Scheme: "http", } ) // Config is the top-level configuration for Prometheus's config files. type Config struct { GlobalConfig GlobalConfig `yaml:"global"` RuleFiles []string `yaml:"rule_files,omitempty"` ScrapeConfigs []*ScrapeConfig `yaml:"scrape_configs,omitempty"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` // original is the input from which the config was parsed. original string } func checkOverflow(m map[string]interface{}, ctx string) error { if len(m) > 0 { var keys []string for k := range m { keys = append(keys, k) } return fmt.Errorf("unknown fields in %s: %s", ctx, strings.Join(keys, ", ")) } return nil } func (c Config) String() string { if c.original != "" { return c.original } b, err := yaml.Marshal(c) if err != nil { return fmt.Sprintf("", err) } return string(b) } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *Config) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultConfig // We want to set c to the defaults and then overwrite it with the input. // To make unmarshal fill the plain data struct rather than calling UnmarshalYAML // again, we have to hide it using a type indirection. type plain Config if err := unmarshal((*plain)(c)); err != nil { return err } for _, rf := range c.RuleFiles { if !patRulePath.MatchString(rf) { return fmt.Errorf("invalid rule file path %q", rf) } } // Do global overrides and validate unique names. jobNames := map[string]struct{}{} for _, scfg := range c.ScrapeConfigs { if scfg.ScrapeInterval == 0 { scfg.ScrapeInterval = c.GlobalConfig.ScrapeInterval } if scfg.ScrapeTimeout == 0 { scfg.ScrapeTimeout = c.GlobalConfig.ScrapeTimeout } if _, ok := jobNames[scfg.JobName]; ok { return fmt.Errorf("found multiple scrape configs with job name %q", scfg.JobName) } jobNames[scfg.JobName] = struct{}{} } return checkOverflow(c.XXX, "config") } // GlobalConfig configures values that are used across other configuration // objects. type GlobalConfig struct { // How frequently to scrape targets by default. ScrapeInterval Duration `yaml:"scrape_interval,omitempty"` // The default timeout when scraping targets. ScrapeTimeout Duration `yaml:"scrape_timeout,omitempty"` // How frequently to evaluate rules by default. EvaluationInterval Duration `yaml:"evaluation_interval,omitempty"` // The labels to add to any timeseries that this Prometheus instance scrapes. Labels clientmodel.LabelSet `yaml:"labels,omitempty"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *GlobalConfig) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultGlobalConfig type plain GlobalConfig if err := unmarshal((*plain)(c)); err != nil { return err } return checkOverflow(c.XXX, "global config") } // ScrapeConfig configures a scraping unit for Prometheus. type ScrapeConfig struct { // The job name to which the job label is set by default. JobName string `yaml:"job_name"` // How frequently to scrape the targets of this scrape config. ScrapeInterval Duration `yaml:"scrape_interval,omitempty"` // The timeout for scraping targets of this config. ScrapeTimeout Duration `yaml:"scrape_timeout,omitempty"` // The HTTP resource path on which to fetch metrics from targets. MetricsPath string `yaml:"metrics_path,omitempty"` // The URL scheme with which to fetch metrics from targets. Scheme string `yaml:"scheme,omitempty"` // The HTTP basic authentication credentials for the targets. BasicAuth *BasicAuth `yaml:"basic_auth,omitempty"` // List of labeled target groups for this job. TargetGroups []*TargetGroup `yaml:"target_groups,omitempty"` // List of DNS service discovery configurations. DNSSDConfigs []*DNSSDConfig `yaml:"dns_sd_configs,omitempty"` // List of file service discovery configurations. FileSDConfigs []*FileSDConfig `yaml:"file_sd_configs,omitempty"` // List of Consul service discovery configurations. ConsulSDConfigs []*ConsulSDConfig `yaml:"consul_sd_configs,omitempty"` // List of relabel configurations. RelabelConfigs []*RelabelConfig `yaml:"relabel_configs,omitempty"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *ScrapeConfig) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultScrapeConfig type plain ScrapeConfig err := unmarshal((*plain)(c)) if err != nil { return err } if !patJobName.MatchString(c.JobName) { return fmt.Errorf("%q is not a valid job name", c.JobName) } return checkOverflow(c.XXX, "scrape_config") } // BasicAuth contains basic HTTP authentication credentials. type BasicAuth struct { Username string `yaml:"username"` Password string `yaml:"password"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (a *BasicAuth) UnmarshalYAML(unmarshal func(interface{}) error) error { type plain BasicAuth err := unmarshal((*plain)(a)) if err != nil { return err } return checkOverflow(a.XXX, "basic_auth") } // TargetGroup is a set of targets with a common label set. type TargetGroup struct { // Targets is a list of targets identified by a label set. Each target is // uniquely identifiable in the group by its address label. Targets []clientmodel.LabelSet // Labels is a set of labels that is common across all targets in the group. Labels clientmodel.LabelSet // Source is an identifier that describes a group of targets. Source string } func (tg TargetGroup) String() string { return tg.Source } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (tg *TargetGroup) UnmarshalYAML(unmarshal func(interface{}) error) error { g := struct { Targets []string `yaml:"targets"` Labels clientmodel.LabelSet `yaml:"labels"` XXX map[string]interface{} `yaml:",inline"` }{} if err := unmarshal(&g); err != nil { return err } tg.Targets = make([]clientmodel.LabelSet, 0, len(g.Targets)) for _, t := range g.Targets { if strings.Contains(t, "/") { return fmt.Errorf("%q is not a valid hostname", t) } tg.Targets = append(tg.Targets, clientmodel.LabelSet{ clientmodel.AddressLabel: clientmodel.LabelValue(t), }) } tg.Labels = g.Labels return checkOverflow(g.XXX, "target_group") } // MarshalYAML implements the yaml.Marshaler interface. func (tg TargetGroup) MarshalYAML() (interface{}, error) { g := &struct { Targets []string `yaml:"targets"` Labels clientmodel.LabelSet `yaml:"labels,omitempty"` }{ Targets: make([]string, 0, len(tg.Targets)), Labels: tg.Labels, } for _, t := range tg.Targets { g.Targets = append(g.Targets, string(t[clientmodel.AddressLabel])) } return g, nil } // UnmarshalJSON implements the json.Unmarshaler interface. func (tg *TargetGroup) UnmarshalJSON(b []byte) error { g := struct { Targets []string `json:"targets"` Labels clientmodel.LabelSet `json:"labels"` }{} if err := json.Unmarshal(b, &g); err != nil { return err } tg.Targets = make([]clientmodel.LabelSet, 0, len(g.Targets)) for _, t := range g.Targets { if strings.Contains(t, "/") { return fmt.Errorf("%q is not a valid hostname", t) } tg.Targets = append(tg.Targets, clientmodel.LabelSet{ clientmodel.AddressLabel: clientmodel.LabelValue(t), }) } tg.Labels = g.Labels return nil } // DNSSDConfig is the configuration for DNS based service discovery. type DNSSDConfig struct { Names []string `yaml:"names"` RefreshInterval Duration `yaml:"refresh_interval,omitempty"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *DNSSDConfig) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultDNSSDConfig type plain DNSSDConfig err := unmarshal((*plain)(c)) if err != nil { return err } if len(c.Names) == 0 { return fmt.Errorf("DNS-SD config must contain at least one SRV record name") } return checkOverflow(c.XXX, "dns_sd_config") } // FileSDConfig is the configuration for file based discovery. type FileSDConfig struct { Names []string `yaml:"names"` RefreshInterval Duration `yaml:"refresh_interval,omitempty"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *FileSDConfig) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultFileSDConfig type plain FileSDConfig err := unmarshal((*plain)(c)) if err != nil { return err } if len(c.Names) == 0 { return fmt.Errorf("file service discovery config must contain at least one path name") } for _, name := range c.Names { if !patFileSDName.MatchString(name) { return fmt.Errorf("path name %q is not valid for file discovery", name) } } return checkOverflow(c.XXX, "file_sd_config") } // ConsulSDConfig is the configuration for Consul service discovery. type ConsulSDConfig struct { Server string `yaml:"server"` Token string `yaml:"token"` Datacenter string `yaml:"datacenter"` TagSeparator string `yaml:"tag_separator"` Scheme string `yaml:"scheme"` Username string `yaml:"username"` Password string `yaml:"password"` // The list of services for which targets are discovered. Services []string `yaml:"services"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *ConsulSDConfig) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultConsulSDConfig type plain ConsulSDConfig err := unmarshal((*plain)(c)) if err != nil { return err } if strings.TrimSpace(c.Server) == "" { return fmt.Errorf("Consul SD configuration requires a server address") } if len(c.Services) == 0 { return fmt.Errorf("Consul SD configuration requires at least one service name") } return checkOverflow(c.XXX, "consul_sd_config") } // RelabelAction is the action to be performed on relabeling. type RelabelAction string const ( // Performs a regex replacement. RelabelReplace RelabelAction = "replace" // Drops targets for which the input does not match the regex. RelabelKeep = "keep" // Drops targets for which the input does match the regex. RelabelDrop = "drop" ) // UnmarshalYAML implements the yaml.Unmarshaler interface. func (a *RelabelAction) UnmarshalYAML(unmarshal func(interface{}) error) error { var s string if err := unmarshal(&s); err != nil { return err } switch act := RelabelAction(strings.ToLower(s)); act { case RelabelReplace, RelabelKeep, RelabelDrop: *a = act return nil } return fmt.Errorf("unknown relabel action %q", s) } // RelabelConfig is the configuration for relabeling of target label sets. type RelabelConfig struct { // A list of labels from which values are taken and concatenated // with the configured separator in order. SourceLabels clientmodel.LabelNames `yaml:"source_labels,flow"` // Separator is the string between concatenated values from the source labels. Separator string `yaml:"separator,omitempty"` // Regex against which the concatenation is matched. Regex *Regexp `yaml:"regex"` // The label to which the resulting string is written in a replacement. TargetLabel clientmodel.LabelName `yaml:"target_label,omitempty"` // Replacement is the regex replacement pattern to be used. Replacement string `yaml:"replacement,omitempty"` // Action is the action to be performed for the relabeling. Action RelabelAction `yaml:"action,omitempty"` // Catches all undefined fields and must be empty after parsing. XXX map[string]interface{} `yaml:",inline"` } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (c *RelabelConfig) UnmarshalYAML(unmarshal func(interface{}) error) error { *c = DefaultRelabelConfig type plain RelabelConfig if err := unmarshal((*plain)(c)); err != nil { return err } if c.Regex == nil { return fmt.Errorf("relabel configuration requires a regular expression") } return checkOverflow(c.XXX, "relabel_config") } // Regexp encapsulates a regexp.Regexp and makes it YAML marshallable. type Regexp struct { regexp.Regexp } // UnmarshalYAML implements the yaml.Unmarshaler interface. func (re *Regexp) UnmarshalYAML(unmarshal func(interface{}) error) error { var s string if err := unmarshal(&s); err != nil { return err } regex, err := regexp.Compile(s) if err != nil { return err } re.Regexp = *regex return nil } // MarshalYAML implements the yaml.Marshaler interface. func (re Regexp) MarshalYAML() (interface{}, error) { return re.String(), nil } // Duration encapsulates a time.Duration and makes it YAML marshallable. // // TODO(fabxc): Since we have custom types for most things, including timestamps, // we might want to move this into our model as well, eventually. type Duration time.Duration // UnmarshalYAML implements the yaml.Unmarshaler interface. func (d *Duration) UnmarshalYAML(unmarshal func(interface{}) error) error { var s string if err := unmarshal(&s); err != nil { return err } dur, err := strutil.StringToDuration(s) if err != nil { return err } *d = Duration(dur) return nil } // MarshalYAML implements the yaml.Marshaler interface. func (d Duration) MarshalYAML() (interface{}, error) { return strutil.DurationToString(time.Duration(d)), nil }