prometheus/config/config.go
Fabian Reinartz 116e6df096 config: raise error on unknown config parameters.
The YAML parser ignores additional parameters on unmarshaling. This causes
frequent confusion with bad configs that pass parsing.
These changes raise errors on additional parameters.
2015-06-12 13:42:56 +02:00

514 lines
16 KiB
Go

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("<error creating config string: %s>", 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
}