Documentation
¶
Overview ¶
Package ha implements a high availability clustering mode for the agent. It is also referred to as the "scraping service" mode, as this is a fairly accurate description of what it does: a series of configs are stored in a KV store and a cluster of agents pulls configs from the store and shards them amongst the cluster, thereby distributing scraping load.
Index ¶
- Variables
- func GetCodec() codec.Codec
- type APIHandler
- type Config
- type InstanceManager
- type ReadRing
- type Server
- func (s *Server) AllConfigs(ctx context.Context) (<-chan instance.Config, error)
- func (s *Server) DeleteConfiguration(r *http.Request) (interface{}, error)
- func (s *Server) Flush()
- func (s *Server) GetConfiguration(r *http.Request) (interface{}, error)
- func (s *Server) ListConfigurations(r *http.Request) (interface{}, error)
- func (s *Server) PutConfiguration(r *http.Request) (interface{}, error)
- func (s *Server) Reshard(ctx context.Context, _ *agentproto.ReshardRequest) (_ *empty.Empty, err error)
- func (s *Server) Stop() error
- func (s *Server) TransferOut(ctx context.Context) error
- func (s *Server) WireAPI(r *mux.Router)
- func (s *Server) WireGRPC(srv *grpc.Server)
- func (s *Server) WrapHandler(next APIHandler) http.HandlerFunc
- type ShardingInstanceManager
Constants ¶
This section is empty.
Variables ¶
var ( // DefaultConfig provides default values for the config DefaultConfig = *flagutil.DefaultConfigFromFlags(&Config{}).(*Config) )
Functions ¶
Types ¶
type APIHandler ¶
APIHandler is a function that returns a configapi Response type and optionally an error.
type Config ¶
type Config struct {
Enabled bool `yaml:"enabled"`
ReshardInterval time.Duration `yaml:"reshard_interval"`
KVStore kv.Config `yaml:"kvstore"`
Lifecycler ring.LifecyclerConfig `yaml:"lifecycler"`
}
Config describes how to instantiate a scraping service Server instance.
func (*Config) RegisterFlags ¶
RegisterFlags adds the flags required to config the Server to the given FlagSet.
func (*Config) RegisterFlagsWithPrefix ¶
RegisterFlagsWithPrefix adds the flags required to config this to the given FlagSet with a specified prefix.
func (*Config) UnmarshalYAML ¶ added in v0.4.0
UnmarshalYAML implements yaml.Unmarshaler.
type InstanceManager ¶ added in v0.4.0
type InstanceManager interface {
// ListConfigs gets the list of currently known configs.
ListConfigs() map[string]instance.Config
// ApplyConfig adds or updates a config.
ApplyConfig(c instance.Config) error
// DeleteConfig deletes a config by name, uniquely keyed by the
// Name field in instance.Config.
DeleteConfig(name string) error
}
InstanceManager is an interface to manipulating a set of running instance.Configs. It is satisfied by the InstanceManager struct in pkg/prom, but is provided as an interface here for testing and avoiding import cycles.
type ReadRing ¶
type ReadRing interface {
http.Handler
Get(key uint32, op ring.Operation, buf []ring.IngesterDesc) (ring.ReplicationSet, error)
GetAll() (ring.ReplicationSet, error)
}
ReadRing is a subset of the Cortex ring.ReadRing interface with only the functionality used by the HA server.
type Server ¶
type Server struct {
// contains filtered or unexported fields
}
Server implements the HA scraping service.
func New ¶
func New(cfg Config, globalConfig *config.GlobalConfig, clientConfig client.Config, logger log.Logger, im InstanceManager) (*Server, error)
New creates a new HA scraping service instance.
func (*Server) AllConfigs ¶
AllConfigs gets all configs known to the KV store.
func (*Server) DeleteConfiguration ¶
DeleteConfiguration deletes an existing named configuration.
func (*Server) Flush ¶
func (s *Server) Flush()
Flush satisfies ring.FlushTransferer. It is a no-op for the Agent.
func (*Server) GetConfiguration ¶
GetConfiguration returns an existing named configuration.
func (*Server) ListConfigurations ¶
ListConfigurations returns a list of the named configurations or all configurations associated with the Prometheus agent.
func (*Server) PutConfiguration ¶
PutConfiguration creates or updates a named configuration. Completely overrides the previous configuration if it exists.
func (*Server) Reshard ¶
func (s *Server) Reshard(ctx context.Context, _ *agentproto.ReshardRequest) (_ *empty.Empty, err error)
Reshard initiates an entire reshard of the current HA scraping service instance. All configs will be reloaded from the KV store and the scraping service instance will see what should be managed locally.
Satisfies agentproto.ScrapingServiceServer.
func (*Server) TransferOut ¶
TransferOut satisfies ring.FlushTransferer. It connects to all other healthy agents in the cluster and tells them to reshard.
func (*Server) WireAPI ¶
WireAPI injects routes into the provided mux router for the config management API.
func (*Server) WrapHandler ¶
func (s *Server) WrapHandler(next APIHandler) http.HandlerFunc
WrapHandler is responsible for turning an APIHandler into an HTTP handler by wrapping responses and writing them as JSON.
type ShardingInstanceManager ¶ added in v0.4.0
type ShardingInstanceManager struct {
// contains filtered or unexported fields
}
ShardingInstanceManager wraps around an existing InstanceManager and uses a hash ring to determine if a config should be applied. If an applied config used to be owned by the local address but no longer does, it will be deleted on the next apply.
func NewShardingInstanceManager ¶ added in v0.4.0
func NewShardingInstanceManager(logger log.Logger, wrap InstanceManager, ring ReadRing, addr string) ShardingInstanceManager
NewShardingInstanceManager creates a new ShardingInstanceManager that wraps around an underlying InstanceManager. ring and addr are used together to do hash ring lookups; for a given applied config, it is owned by the instance of ShardingInstanceManager if looking up its hash in the ring results in the address specified by addr.
func (ShardingInstanceManager) ApplyConfig ¶ added in v0.4.0
func (m ShardingInstanceManager) ApplyConfig(c instance.Config) error
ApplyConfig implements InstanceManager.ApplyConfig.
func (ShardingInstanceManager) DeleteConfig ¶ added in v0.4.0
func (m ShardingInstanceManager) DeleteConfig(name string) error
DeleteConfig implements InstanceManager.DeleteConfig.
func (ShardingInstanceManager) ListConfigs ¶ added in v0.4.0
func (m ShardingInstanceManager) ListConfigs() map[string]instance.Config
ListConfigs returns the list of configs that have been applied through the ShardingInstanceManager. It will return a subset of the overall set of configs passed to the InstanceManager as a whole.
Returning the subset of configs that only the ShardingInstanceManager applied itself allows for the underlying InstanceManager to manage its own set of configs that will not be affected by the scraping service resharding and deleting configs that aren't found in the KV store.
Source Files
Directories