Documentation ¶
Overview ¶
Package embed provides bindings for embedding an etcd server in a program.
Launch an embedded etcd server using the configuration defaults:
import ( "log" "time" "go.etcd.io/etcd/server/v3/embed" ) func main() { cfg := embed.NewConfig() cfg.Dir = "default.etcd" e, err := embed.StartEtcd(cfg) if err != nil { log.Fatal(err) } defer e.Close() select { case <-e.Server.ReadyNotify(): log.Printf("Server is ready!") case <-time.After(60 * time.Second): e.Server.Stop() // trigger a shutdown log.Printf("Server took too long to start!") } log.Fatal(<-e.Err()) }
Index ¶
- Constants
- Variables
- func NewZapCoreLoggerBuilder(lg *zap.Logger, _ zapcore.Core, _ zapcore.WriteSyncer) func(*Config) error
- func NewZapLoggerBuilder(lg *zap.Logger) func(*Config) error
- func WrapCORS(cors map[string]struct{}, h http.Handler) http.Handler
- type Config
- func (cfg *Config) ClientSelfCert() (err error)
- func (cfg Config) ElectionTicks() int
- func (cfg *Config) GetDNSClusterNames() ([]string, error)
- func (cfg Config) GetLogger() *zap.Logger
- func (cfg Config) InitialClusterFromName(name string) (ret string)
- func (cfg Config) IsNewCluster() bool
- func (cfg *Config) PeerSelfCert() (err error)
- func (cfg *Config) PeerURLsMapAndToken(which string) (urlsmap types.URLsMap, token string, err error)
- func (cfg *Config) SetupGlobalLoggers()
- func (cfg *Config) UpdateDefaultClusterFromName(defaultInitialCluster string) (string, error)
- func (cfg Config) V2DeprecationEffective() config.V2DeprecationEnum
- func (cfg *Config) Validate() error
- type Etcd
Constants ¶
const ( ClusterStateFlagNew = "new" ClusterStateFlagExisting = "existing" DefaultName = "default" DefaultMaxSnapshots = 5 DefaultMaxWALs = 5 DefaultMaxTxnOps = uint(128) DefaultWarningApplyDuration = 100 * time.Millisecond DefaultMaxRequestBytes = 1.5 * 1024 * 1024 DefaultMaxConcurrentStreams = math.MaxUint32 DefaultGRPCKeepAliveMinTime = 5 * time.Second DefaultGRPCKeepAliveInterval = 2 * time.Hour DefaultGRPCKeepAliveTimeout = 20 * time.Second DefaultDowngradeCheckTime = 5 * time.Second DefaultListenPeerURLs = "http://localhost:2380" DefaultListenClientURLs = "http://localhost:2379" DefaultLogOutput = "default" JournalLogOutput = "systemd/journal" StdErrLogOutput = "stderr" StdOutLogOutput = "stdout" // DefaultLogRotationConfig is the default configuration used for log rotation. // Log rotation is disabled by default. // MaxSize = 100 // MB // MaxAge = 0 // days (no limit) // MaxBackups = 0 // no limit // LocalTime = false // use computers local time, UTC by default // Compress = false // compress the rotated log in gzip format DefaultLogRotationConfig = `{"maxsize": 100, "maxage": 0, "maxbackups": 0, "localtime": false, "compress": false}` // ExperimentalDistributedTracingAddress is the default collector address. ExperimentalDistributedTracingAddress = "localhost:4317" // ExperimentalDistributedTracingServiceName is the default etcd service name. ExperimentalDistributedTracingServiceName = "etcd" // DefaultStrictReconfigCheck is the default value for "--strict-reconfig-check" flag. // It's enabled by default. DefaultStrictReconfigCheck = true // DefaultEnableV2 is the default value for "--enable-v2" flag. // v2 API is disabled by default. DefaultEnableV2 = false )
Variables ¶
var ( ErrConflictBootstrapFlags = fmt.Errorf("multiple discovery or bootstrap flags are set. " + "Choose one of \"initial-cluster\", \"discovery\" or \"discovery-srv\"") ErrUnsetAdvertiseClientURLsFlag = fmt.Errorf("--advertise-client-urls is required when --listen-client-urls is set explicitly") ErrLogRotationInvalidLogOutput = fmt.Errorf("--log-outputs requires a single file path when --log-rotate-config-json is defined") DefaultInitialAdvertisePeerURLs = "http://localhost:2380" DefaultAdvertiseClientURLs = "http://localhost:2379" )
var ( // CompactorModePeriodic is periodic compaction mode // for "Config.AutoCompactionMode" field. // If "AutoCompactionMode" is CompactorModePeriodic and // "AutoCompactionRetention" is "1h", it automatically compacts // compacts storage every hour. CompactorModePeriodic = v3compactor.ModePeriodic // CompactorModeRevision is revision-based compaction mode // for "Config.AutoCompactionMode" field. // If "AutoCompactionMode" is CompactorModeRevision and // "AutoCompactionRetention" is "1000", it compacts log on // revision 5000 when the current revision is 6000. // This runs every 5-minute if enough of logs have proceeded. CompactorModeRevision = v3compactor.ModeRevision )
Functions ¶
func NewZapCoreLoggerBuilder ¶
func NewZapCoreLoggerBuilder(lg *zap.Logger, _ zapcore.Core, _ zapcore.WriteSyncer) func(*Config) error
NewZapCoreLoggerBuilder - is a deprecated setter for the logger. Deprecated: Use simpler NewZapLoggerBuilder. To be removed in etcd-3.6.
func NewZapLoggerBuilder ¶
NewZapLoggerBuilder generates a zap logger builder that sets given loger for embedded etcd.
Types ¶
type Config ¶
type Config struct { Name string `json:"name"` Dir string `json:"data-dir"` WalDir string `json:"wal-dir"` SnapshotCount uint64 `json:"snapshot-count"` // SnapshotCatchUpEntries is the number of entries for a slow follower // to catch-up after compacting the raft storage entries. // We expect the follower has a millisecond level latency with the leader. // The max throughput is around 10K. Keep a 5K entries is enough for helping // follower to catch up. // WARNING: only change this for tests. // Always use "DefaultSnapshotCatchUpEntries" SnapshotCatchUpEntries uint64 MaxSnapFiles uint `json:"max-snapshots"` MaxWalFiles uint `json:"max-wals"` // TickMs is the number of milliseconds between heartbeat ticks. // TODO: decouple tickMs and heartbeat tick (current heartbeat tick = 1). // make ticks a cluster wide configuration. TickMs uint `json:"heartbeat-interval"` ElectionMs uint `json:"election-timeout"` // InitialElectionTickAdvance is true, then local member fast-forwards // election ticks to speed up "initial" leader election trigger. This // benefits the case of larger election ticks. For instance, cross // datacenter deployment may require longer election timeout of 10-second. // If true, local node does not need wait up to 10-second. Instead, // forwards its election ticks to 8-second, and have only 2-second left // before leader election. // // Major assumptions are that: // - cluster has no active leader thus advancing ticks enables faster // leader election, or // - cluster already has an established leader, and rejoining follower // is likely to receive heartbeats from the leader after tick advance // and before election timeout. // // However, when network from leader to rejoining follower is congested, // and the follower does not receive leader heartbeat within left election // ticks, disruptive election has to happen thus affecting cluster // availabilities. // // Disabling this would slow down initial bootstrap process for cross // datacenter deployments. Make your own tradeoffs by configuring // --initial-election-tick-advance at the cost of slow initial bootstrap. // // If single-node, it advances ticks regardless. // // See https://github.com/etcd-io/etcd/issues/9333 for more detail. InitialElectionTickAdvance bool `json:"initial-election-tick-advance"` // BackendBatchInterval is the maximum time before commit the backend transaction. BackendBatchInterval time.Duration `json:"backend-batch-interval"` // BackendBatchLimit is the maximum operations before commit the backend transaction. BackendBatchLimit int `json:"backend-batch-limit"` // BackendFreelistType specifies the type of freelist that boltdb backend uses (array and map are supported types). BackendFreelistType string `json:"backend-bbolt-freelist-type"` QuotaBackendBytes int64 `json:"quota-backend-bytes"` MaxTxnOps uint `json:"max-txn-ops"` MaxRequestBytes uint `json:"max-request-bytes"` // MaxConcurrentStreams specifies the maximum number of concurrent // streams that each client can open at a time. MaxConcurrentStreams uint32 `json:"max-concurrent-streams"` ListenPeerUrls, ListenClientUrls, ListenClientHttpUrls []url.URL AdvertisePeerUrls, AdvertiseClientUrls []url.URL ClientTLSInfo transport.TLSInfo ClientAutoTLS bool PeerTLSInfo transport.TLSInfo PeerAutoTLS bool // SelfSignedCertValidity specifies the validity period of the client and peer certificates // that are automatically generated by etcd when you specify ClientAutoTLS and PeerAutoTLS, // the unit is year, and the default is 1 SelfSignedCertValidity uint `json:"self-signed-cert-validity"` // CipherSuites is a list of supported TLS cipher suites between // client/server and peers. If empty, Go auto-populates the list. // Note that cipher suites are prioritized in the given order. CipherSuites []string `json:"cipher-suites"` // TlsMinVersion is the minimum accepted TLS version between client/server and peers. TlsMinVersion string `json:"tls-min-version"` // TlsMaxVersion is the maximum accepted TLS version between client/server and peers. TlsMaxVersion string `json:"tls-max-version"` ClusterState string `json:"initial-cluster-state"` DNSCluster string `json:"discovery-srv"` DNSClusterServiceName string `json:"discovery-srv-name"` Dproxy string `json:"discovery-proxy"` Durl string `json:"discovery"` InitialCluster string `json:"initial-cluster"` InitialClusterToken string `json:"initial-cluster-token"` StrictReconfigCheck bool `json:"strict-reconfig-check"` // EnableV2 exposes the deprecated V2 API surface. // TODO: Delete in 3.6 (https://github.com/etcd-io/etcd/issues/12913) // Deprecated in 3.5. EnableV2 bool `json:"enable-v2"` // AutoCompactionMode is either 'periodic' or 'revision'. AutoCompactionMode string `json:"auto-compaction-mode"` // AutoCompactionRetention is either duration string with time unit // (e.g. '5m' for 5-minute), or revision unit (e.g. '5000'). // If no time unit is provided and compaction mode is 'periodic', // the unit defaults to hour. For example, '5' translates into 5-hour. AutoCompactionRetention string `json:"auto-compaction-retention"` // GRPCKeepAliveMinTime is the minimum interval that a client should // wait before pinging server. When client pings "too fast", server // sends goaway and closes the connection (errors: too_many_pings, // http2.ErrCodeEnhanceYourCalm). When too slow, nothing happens. // Server expects client pings only when there is any active streams // (PermitWithoutStream is set false). GRPCKeepAliveMinTime time.Duration `json:"grpc-keepalive-min-time"` // GRPCKeepAliveInterval is the frequency of server-to-client ping // to check if a connection is alive. Close a non-responsive connection // after an additional duration of Timeout. 0 to disable. GRPCKeepAliveInterval time.Duration `json:"grpc-keepalive-interval"` // GRPCKeepAliveTimeout is the additional duration of wait // before closing a non-responsive connection. 0 to disable. GRPCKeepAliveTimeout time.Duration `json:"grpc-keepalive-timeout"` // SocketOpts are socket options passed to listener config. SocketOpts transport.SocketOpts // PreVote is true to enable Raft Pre-Vote. // If enabled, Raft runs an additional election phase // to check whether it would get enough votes to win // an election, thus minimizing disruptions. PreVote bool `json:"pre-vote"` CORS map[string]struct{} // HostWhitelist lists acceptable hostnames from HTTP client requests. // Client origin policy protects against "DNS Rebinding" attacks // to insecure etcd servers. That is, any website can simply create // an authorized DNS name, and direct DNS to "localhost" (or any // other address). Then, all HTTP endpoints of etcd server listening // on "localhost" becomes accessible, thus vulnerable to DNS rebinding // attacks. See "CVE-2018-5702" for more detail. // // 1. If client connection is secure via HTTPS, allow any hostnames. // 2. If client connection is not secure and "HostWhitelist" is not empty, // only allow HTTP requests whose Host field is listed in whitelist. // // Note that the client origin policy is enforced whether authentication // is enabled or not, for tighter controls. // // By default, "HostWhitelist" is "*", which allows any hostnames. // Note that when specifying hostnames, loopback addresses are not added // automatically. To allow loopback interfaces, leave it empty or set it "*", // or add them to whitelist manually (e.g. "localhost", "127.0.0.1", etc.). // // CVE-2018-5702 reference: // - https://bugs.chromium.org/p/project-zero/issues/detail?id=1447#c2 // - https://github.com/transmission/transmission/pull/468 // - https://github.com/etcd-io/etcd/issues/9353 HostWhitelist map[string]struct{} // UserHandlers is for registering users handlers and only used for // embedding etcd into other applications. // The map key is the route path for the handler, and // you must ensure it can't be conflicted with etcd's. UserHandlers map[string]http.Handler `json:"-"` // ServiceRegister is for registering users' gRPC services. A simple usage example: // cfg := embed.NewConfig() // cfg.ServerRegister = func(s *grpc.Server) { // pb.RegisterFooServer(s, &fooServer{}) // pb.RegisterBarServer(s, &barServer{}) // } // embed.StartEtcd(cfg) ServiceRegister func(*grpc.Server) `json:"-"` AuthToken string `json:"auth-token"` BcryptCost uint `json:"bcrypt-cost"` // AuthTokenTTL specifies the TTL in seconds of the simple token AuthTokenTTL uint `json:"auth-token-ttl"` ExperimentalInitialCorruptCheck bool `json:"experimental-initial-corrupt-check"` ExperimentalCorruptCheckTime time.Duration `json:"experimental-corrupt-check-time"` ExperimentalCompactHashCheckEnabled bool `json:"experimental-compact-hash-check-enabled"` ExperimentalCompactHashCheckTime time.Duration `json:"experimental-compact-hash-check-time"` // ExperimentalEnableV2V3 configures URLs that expose deprecated V2 API working on V3 store. // Deprecated in v3.5. // TODO: Delete in v3.6 (https://github.com/etcd-io/etcd/issues/12913) ExperimentalEnableV2V3 string `json:"experimental-enable-v2v3"` // ExperimentalEnableLeaseCheckpoint enables leader to send regular checkpoints to other members to prevent reset of remaining TTL on leader change. ExperimentalEnableLeaseCheckpoint bool `json:"experimental-enable-lease-checkpoint"` // ExperimentalEnableLeaseCheckpointPersist enables persisting remainingTTL to prevent indefinite auto-renewal of long lived leases. Always enabled in v3.6. Should be used to ensure smooth upgrade from v3.5 clusters with this feature enabled. // Requires experimental-enable-lease-checkpoint to be enabled. // Deprecated in v3.6. // TODO: Delete in v3.7 ExperimentalEnableLeaseCheckpointPersist bool `json:"experimental-enable-lease-checkpoint-persist"` ExperimentalCompactionBatchLimit int `json:"experimental-compaction-batch-limit"` ExperimentalWatchProgressNotifyInterval time.Duration `json:"experimental-watch-progress-notify-interval"` // ExperimentalWarningApplyDuration is the time duration after which a warning is generated if applying request // takes more time than this value. ExperimentalWarningApplyDuration time.Duration `json:"experimental-warning-apply-duration"` // ExperimentalBootstrapDefragThresholdMegabytes is the minimum number of megabytes needed to be freed for etcd server to // consider running defrag during bootstrap. Needs to be set to non-zero value to take effect. ExperimentalBootstrapDefragThresholdMegabytes uint `json:"experimental-bootstrap-defrag-threshold-megabytes"` // ForceNewCluster starts a new cluster even if previously started; unsafe. ForceNewCluster bool `json:"force-new-cluster"` EnablePprof bool `json:"enable-pprof"` Metrics string `json:"metrics"` ListenMetricsUrls []url.URL ListenMetricsUrlsJSON string `json:"listen-metrics-urls"` // ExperimentalEnableDistributedTracing indicates if experimental tracing using OpenTelemetry is enabled. ExperimentalEnableDistributedTracing bool `json:"experimental-enable-distributed-tracing"` // ExperimentalDistributedTracingAddress is the address of the OpenTelemetry Collector. // Can only be set if ExperimentalEnableDistributedTracing is true. ExperimentalDistributedTracingAddress string `json:"experimental-distributed-tracing-address"` // ExperimentalDistributedTracingServiceName is the name of the service. // Can only be used if ExperimentalEnableDistributedTracing is true. ExperimentalDistributedTracingServiceName string `json:"experimental-distributed-tracing-service-name"` // ExperimentalDistributedTracingServiceInstanceID is the ID key of the service. // This ID must be unique, as helps to distinguish instances of the same service // that exist at the same time. // Can only be used if ExperimentalEnableDistributedTracing is true. ExperimentalDistributedTracingServiceInstanceID string `json:"experimental-distributed-tracing-instance-id"` // Logger is logger options: currently only supports "zap". // "capnslog" is removed in v3.5. Logger string `json:"logger"` // LogLevel configures log level. Only supports debug, info, warn, error, panic, or fatal. Default 'info'. LogLevel string `json:"log-level"` // LogOutputs is either: // - "default" as os.Stderr, // - "stderr" as os.Stderr, // - "stdout" as os.Stdout, // - file path to append server logs to. // It can be multiple when "Logger" is zap. LogOutputs []string `json:"log-outputs"` // EnableLogRotation enables log rotation of a single LogOutputs file target. EnableLogRotation bool `json:"enable-log-rotation"` // LogRotationConfigJSON is a passthrough allowing a log rotation JSON config to be passed directly. LogRotationConfigJSON string `json:"log-rotation-config-json"` // ZapLoggerBuilder is used to build the zap logger. ZapLoggerBuilder func(*Config) error // EnableGRPCGateway enables grpc gateway. // The gateway translates a RESTful HTTP API into gRPC. EnableGRPCGateway bool `json:"enable-grpc-gateway"` // UnsafeNoFsync disables all uses of fsync. // Setting this is unsafe and will cause data loss. UnsafeNoFsync bool `json:"unsafe-no-fsync"` ExperimentalDowngradeCheckTime time.Duration `json:"experimental-downgrade-check-time"` // ExperimentalMemoryMlock enables mlocking of etcd owned memory pages. // The setting improves etcd tail latency in environments were: // - memory pressure might lead to swapping pages to disk // - disk latency might be unstable // Currently all etcd memory gets mlocked, but in future the flag can // be refined to mlock in-use area of bbolt only. ExperimentalMemoryMlock bool `json:"experimental-memory-mlock"` ExperimentalTxnModeWriteWithSharedBuffer bool `json:"experimental-txn-mode-write-with-shared-buffer"` // V2Deprecation describes phase of API & Storage V2 support V2Deprecation config.V2DeprecationEnum `json:"v2-deprecation"` // contains filtered or unexported fields }
Config holds the arguments for configuring an etcd server.
func ConfigFromFile ¶
func NewConfig ¶
func NewConfig() *Config
NewConfig creates a new Config populated with default values.
func (*Config) ClientSelfCert ¶
func (Config) ElectionTicks ¶
func (*Config) GetDNSClusterNames ¶
GetDNSClusterNames uses DNS SRV records to get a list of initial nodes for cluster bootstrapping. This function will return a list of one or more nodes, as well as any errors encountered while performing service discovery. Note: Because this checks multiple sets of SRV records, discovery should only be considered to have failed if the returned node list is empty.
func (Config) InitialClusterFromName ¶
func (Config) IsNewCluster ¶
func (*Config) PeerSelfCert ¶
func (*Config) PeerURLsMapAndToken ¶
func (cfg *Config) PeerURLsMapAndToken(which string) (urlsmap types.URLsMap, token string, err error)
PeerURLsMapAndToken sets up an initial peer URLsMap and cluster token for bootstrap or discovery.
func (*Config) SetupGlobalLoggers ¶
func (cfg *Config) SetupGlobalLoggers()
SetupGlobalLoggers configures 'global' loggers (grpc, zapGlobal) based on the cfg.
The method is not executed by embed server by default (since 3.5) to enable setups where grpc/zap.Global logging is configured independently or spans separate lifecycle (like in tests).
func (*Config) UpdateDefaultClusterFromName ¶
UpdateDefaultClusterFromName updates cluster advertise URLs with, if available, default host, if advertise URLs are default values(localhost:2379,2380) AND if listen URL is 0.0.0.0. e.g. advertise peer URL localhost:2380 or listen peer URL 0.0.0.0:2380 then the advertise peer host would be updated with machine's default host, while keeping the listen URL's port. User can work around this by explicitly setting URL with 127.0.0.1. It returns the default hostname, if used, and the error, if any, from getting the machine's default host. TODO: check whether fields are set instead of whether fields have default value
func (Config) V2DeprecationEffective ¶
func (cfg Config) V2DeprecationEffective() config.V2DeprecationEnum
type Etcd ¶
type Etcd struct { Peers []*peerListener Clients []net.Listener Server *etcdserver.EtcdServer // contains filtered or unexported fields }
Etcd contains a running etcd server and its listeners.
func StartEtcd ¶
StartEtcd launches the etcd server and HTTP handlers for client/server communication. The returned Etcd.Server is not guaranteed to have joined the cluster. Wait on the Etcd.Server.ReadyNotify() channel to know when it completes and is ready for use.
func (*Etcd) Close ¶
func (e *Etcd) Close()
Close gracefully shuts down all servers/listeners. Client requests will be terminated with request timeout. After timeout, enforce remaning requests be closed immediately.