autodiscovery

README

package autodiscovery

This package is a core piece of the agent. It is responsible for collecting checks configurations from different sources (see package config providers) and then schedule or unschedule integrations configurations with the help of the schedulers.

It is also responsible for listening to container-related events and resolve template configurations that would match them.

AutoConfig

As a central component, AutoConfig owns and orchestrates several key modules:

• it owns a reference to a MetaScheduler that dispatches integrations configs for scheduling or unscheduling to all registered schedulers.
• it stores a list of ConfigProviders and poll them according to their policy
• it owns ServiceListener that it uses to listen to container lifecycle events
• it runs the ConfigResolver that resolves a configuration template to an actual configuration based on data it extracts from a service that matches it the template

ConfigResolver

ConfigResolver resolves configuration templates with services and asks AutoConfig to schedule checks based on this resolving.

To fulfill its task, it stores a cache of services (containers) and templates. It also keeps a live map of how they apply to each other and of the checks that it scheduled as a result.

It also listens on three channels, one for fresh configuration templates, and two for newly started/stopped services.

Documentation

Index

• func GetConfigErrors() map[string]string
• func GetResolveWarnings() map[string][]string
• type AutoConfig
  • func NewAutoConfig(scheduler scheduler.Scheduler) *AutoConfig
  • func (ac *AutoConfig) AddListener(listener listeners.ServiceListener)
  • func (ac *AutoConfig) AddProvider(provider providers.ConfigProvider, shouldPoll bool)
  • func (ac *AutoConfig) GetAllConfigs() []integration.Config
  • func (ac *AutoConfig) GetLoadedConfigs() map[string]integration.Config
  • func (ac *AutoConfig) GetUnresolvedTemplates() map[string]integration.Config
  • func (ac *AutoConfig) LoadAndRun()
  • func (ac *AutoConfig) StartPolling()
  • func (ac *AutoConfig) Stop()
• type ConfigResolver
  • func (cr *ConfigResolver) ResolveTemplate(tpl integration.Config) []integration.Config
  • func (cr *ConfigResolver) Stop()
• type TemplateCache
  • func NewTemplateCache() *TemplateCache
  • func (cache *TemplateCache) Del(tpl integration.Config) error
  • func (cache *TemplateCache) Get(adID string) ([]integration.Config, error)
  • func (cache *TemplateCache) GetUnresolvedTemplates() map[string]integration.Config
  • func (cache *TemplateCache) Set(tpl integration.Config) error

Functions

func GetConfigErrors

func GetConfigErrors() map[string]string

GetConfigErrors gets the config errors

func GetResolveWarnings

func GetResolveWarnings() map[string][]string

GetResolveWarnings get the resolve warnings/errors

Types

type AutoConfig

type AutoConfig struct {
	// contains filtered or unexported fields
}

AutoConfig is responsible to collect integrations configurations from different sources and then schedule or unschedule them. It owns and orchestrates several key modules:

• it owns a reference to the `collector.Collector` that it uses to schedule checks when template or container updates warrant them
• it holds a list of `providers.ConfigProvider`s and poll them according to their policy
• it holds a list of `check.Loader`s to load configurations into `Check` objects
• it holds a list of `listeners.ServiceListener`s` used to listen to container lifecycle events
• it runs the `ConfigResolver` that resolves a configuration template to an actual configuration based on data it extracts from a service that matches it the template

Notice the `AutoConfig` public API speaks in terms of `integration.Config`, meaning that you cannot use it to schedule integrations instances directly.

func NewAutoConfig

func NewAutoConfig(scheduler scheduler.Scheduler) *AutoConfig

NewAutoConfig creates an AutoConfig instance.

func (*AutoConfig) AddListener

func (ac *AutoConfig) AddListener(listener listeners.ServiceListener)

AddListener adds a service listener to AutoConfig.

func (*AutoConfig) AddProvider

func (ac *AutoConfig) AddProvider(provider providers.ConfigProvider, shouldPoll bool)

AddProvider adds a new configuration provider to AutoConfig. Callers must pass a flag to indicate whether the configuration provider expects to be polled or it's fine for it to be invoked only once in the Agent lifetime.

func (*AutoConfig) GetAllConfigs

func (ac *AutoConfig) GetAllConfigs() []integration.Config

GetAllConfigs queries all the providers and returns all the integration configurations found, resolving the ones it can

func (*AutoConfig) GetLoadedConfigs

func (ac *AutoConfig) GetLoadedConfigs() map[string]integration.Config

GetLoadedConfigs returns configs loaded

func (*AutoConfig) GetUnresolvedTemplates

func (ac *AutoConfig) GetUnresolvedTemplates() map[string]integration.Config

GetUnresolvedTemplates returns templates in cache yet to be resolved

func (*AutoConfig) LoadAndRun

func (ac *AutoConfig) LoadAndRun()

LoadAndRun loads all of the integration configs it can find and schedules them. Should always be run once so providers that don't need polling will be queried at least once

func (*AutoConfig) StartPolling

func (ac *AutoConfig) StartPolling()

StartPolling starts the goroutine responsible for polling the providers

func (*AutoConfig) Stop

func (ac *AutoConfig) Stop()

Stop just shuts down AutoConfig in a clean way. AutoConfig is not supposed to be restarted, so this is expected to be called only once at program exit.

type ConfigResolver

type ConfigResolver struct {
	// contains filtered or unexported fields
}

ConfigResolver stores services and templates in cache, and matches services it hears about with templates to create valid configs. It is also responsible to send scheduling orders to AutoConfig

func (*ConfigResolver) ResolveTemplate

func (cr *ConfigResolver) ResolveTemplate(tpl integration.Config) []integration.Config

ResolveTemplate attempts to resolve a configuration template using the AD identifiers in the `integration.Config` struct to match a Service.

The function might return more than one configuration for a single template, for example when the `ad_identifiers` section of a config.yaml file contains multiple entries, or when more than one Service has the same identifier, e.g. 'redis'.

The function might return an empty list in the case the configuration has a list of Autodiscovery identifiers for services that are unknown to the resolver at this moment.

func (*ConfigResolver) Stop

func (cr *ConfigResolver) Stop()

Stop shuts down the config resolver

type TemplateCache

type TemplateCache struct {
	// contains filtered or unexported fields
}

TemplateCache is a data structure to store configuration templates

func NewTemplateCache

func NewTemplateCache() *TemplateCache

NewTemplateCache creates a new cache

func (*TemplateCache) Del

func (cache *TemplateCache) Del(tpl integration.Config) error

Del removes a template from the cache

func (*TemplateCache) Get

func (cache *TemplateCache) Get(adID string) ([]integration.Config, error)

Get retrieves a template from the cache

func (*TemplateCache) GetUnresolvedTemplates

func (cache *TemplateCache) GetUnresolvedTemplates() map[string]integration.Config

GetUnresolvedTemplates returns templates yet to be resolved

func (*TemplateCache) Set

func (cache *TemplateCache) Set(tpl integration.Config) error

Set stores or updates a template in the cache