etcd concurrency API Reference

This is a generated documentation. Please read the proto files for more.

service Lock (etcdserver/api/v3lock/v3lockpb/v3lock.proto)

The lock service exposes client-side locking facilities as a gRPC interface.

Method Request Type Response Type Description
Lock LockRequest LockResponse Lock acquires a distributed shared lock on a given named lock. On success, it will return a unique key that exists so long as the lock is held by the caller. This key can be used in conjunction with transactions to safely ensure updates to etcd only occur while holding lock ownership. The lock is held until Unlock is called on the key or the lease associate with the owner expires.
Unlock UnlockRequest UnlockResponse Unlock takes a key returned by Lock and releases the hold on lock. The next Lock caller waiting for the lock will then be woken up and given ownership of the lock.
message LockRequest (etcdserver/api/v3lock/v3lockpb/v3lock.proto)
Field Description Type
name name is the identifier for the distributed shared lock to be acquired. bytes
lease lease is the ID of the lease that will be attached to ownership of the lock. If the lease expires or is revoked and currently holds the lock, the lock is automatically released. Calls to Lock with the same lease will be treated as a single acquistion; locking twice with the same lease is a no-op. int64
message LockResponse (etcdserver/api/v3lock/v3lockpb/v3lock.proto)
Field Description Type
header etcdserverpb.ResponseHeader
key key is a key that will exist on etcd for the duration that the Lock caller owns the lock. Users should not modify this key or the lock may exhibit undefined behavior. bytes
message UnlockRequest (etcdserver/api/v3lock/v3lockpb/v3lock.proto)
Field Description Type
key key is the lock ownership key granted by Lock. bytes
message UnlockResponse (etcdserver/api/v3lock/v3lockpb/v3lock.proto)
Field Description Type
header etcdserverpb.ResponseHeader
service Election (etcdserver/api/v3election/v3electionpb/v3election.proto)

The election service exposes client-side election facilities as a gRPC interface.

Method Request Type Response Type Description
Campaign CampaignRequest CampaignResponse Campaign waits to acquire leadership in an election, returning a LeaderKey representing the leadership if successful. The LeaderKey can then be used to issue new values on the election, transactionally guard API requests on leadership still being held, and resign from the election.
Proclaim ProclaimRequest ProclaimResponse Proclaim updates the leader’s posted value with a new value.
Leader LeaderRequest LeaderResponse Leader returns the current election proclamation, if any.
Observe LeaderRequest LeaderResponse Observe streams election proclamations in-order as made by the election’s elected leaders.
Resign ResignRequest ResignResponse Resign releases election leadership so other campaigners may acquire leadership on the election.
message CampaignRequest (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
name name is the election’s identifier for the campaign. bytes
lease lease is the ID of the lease attached to leadership of the election. If the lease expires or is revoked before resigning leadership, then the leadership is transferred to the next campaigner, if any. int64
value value is the initial proclaimed value set when the campaigner wins the election. bytes
message CampaignResponse (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
header etcdserverpb.ResponseHeader
leader leader describes the resources used for holding leadereship of the election. LeaderKey
message LeaderKey (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
name name is the election identifier that correponds to the leadership key. bytes
key key is an opaque key representing the ownership of the election. If the key is deleted, then leadership is lost. bytes
rev rev is the creation revision of the key. It can be used to test for ownership of an election during transactions by testing the key’s creation revision matches rev. int64
lease lease is the lease ID of the election leader. int64
message LeaderRequest (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
name name is the election identifier for the leadership information. bytes
message LeaderResponse (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
header etcdserverpb.ResponseHeader
kv kv is the key-value pair representing the latest leader update. mvccpb.KeyValue
message ProclaimRequest (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
leader leader is the leadership hold on the election. LeaderKey
value value is an update meant to overwrite the leader’s current value. bytes
message ProclaimResponse (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
header etcdserverpb.ResponseHeader
message ResignRequest (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
leader leader is the leadership to relinquish by resignation. LeaderKey
message ResignResponse (etcdserver/api/v3election/v3electionpb/v3election.proto)
Field Description Type
header etcdserverpb.ResponseHeader
message Event (mvcc/mvccpb/kv.proto)
Field Description Type
type type is the kind of event. If type is a PUT, it indicates new data has been stored to the key. If type is a DELETE, it indicates the key was deleted. EventType
kv kv holds the KeyValue for the event. A PUT event contains current kv pair. A PUT event with kv.Version=1 indicates the creation of a key. A DELETE/EXPIRE event contains the deleted key with its modification revision set to the revision of deletion. KeyValue
prev_kv prev_kv holds the key-value pair before the event happens. KeyValue
message KeyValue (mvcc/mvccpb/kv.proto)
Field Description Type
key key is the key in bytes. An empty key is not allowed. bytes
create_revision create_revision is the revision of last creation on this key. int64
mod_revision mod_revision is the revision of last modification on this key. int64
version version is the version of the key. A deletion resets the version to zero and any modification of the key increases its version. int64
value value is the value held by the key, in bytes. bytes
lease lease is the ID of the lease that attached to key. When the attached lease expires, the key will be deleted. If lease is 0, then no lease is attached to the key. int64