Network.EtcdV3

Simple lib to access Etcd over gRPC.

Generalities.

etcdClientConfigSimple :: HostName -> PortNumber -> UseTlsOrNot -> GrpcClientConfig

EtcdClient configuration.

type EtcdQuery a = IO (Maybe a)

Type alias to simplify type signatures.

Reading.

data KeyRange

Data type to unify the three addressing schemes in etcd.

See range.

Constructors

SingleKey !ByteString

Exactly one key.

FromKey !ByteString

Prefixed !ByteString

Instances

Eq KeyRange

Defined in Network.EtcdV3

Methods

(==) :: KeyRange -> KeyRange -> Bool

(/=) :: KeyRange -> KeyRange -> Bool

Ord KeyRange

Defined in Network.EtcdV3

Methods

compare :: KeyRange -> KeyRange -> Ordering

(<) :: KeyRange -> KeyRange -> Bool

(<=) :: KeyRange -> KeyRange -> Bool

(>) :: KeyRange -> KeyRange -> Bool

(>=) :: KeyRange -> KeyRange -> Bool

max :: KeyRange -> KeyRange -> KeyRange

min :: KeyRange -> KeyRange -> KeyRange

Show KeyRange

Defined in Network.EtcdV3

Methods

showsPrec :: Int -> KeyRange -> ShowS

show :: KeyRange -> String

showList :: [KeyRange] -> ShowS

range

Arguments

:: GrpcClient

Initialized gRPC client.

-> KeyRange

Looked-up range.

-> EtcdQuery RangeResponse

Lookup a range of values

rangeResponsePairs :: Getting (Endo [(ByteString, ByteString)]) RangeResponse (ByteString, ByteString)

Specific fold to get the key-values of a RangeResponse

Typical usage is:

x <- range grpc (Prefixed "some-dir") print $ x ^.. _Just . rangePairs

Note that Etcd RangeResponse is a rich object, please refer to Etcd documentation to understand what you will miss out (e.g., whether the list is complete or not).

Granting leases.

grantLease

Arguments

:: GrpcClient

Initialized gRPC client.

-> Int64

TTL for the lease.

-> EtcdQuery LeaseGrantResponse

Asks for a lease of a given duration.

data GrantedLease

Opaque lease result.

Show instance used for printing purposes only.

Instances

Show GrantedLease

Defined in Network.EtcdV3

Methods

showsPrec :: Int -> GrantedLease -> ShowS

show :: GrantedLease -> String

showList :: [GrantedLease] -> ShowS

fromLeaseGrantResponse :: LeaseGrantResponse -> GrantedLease

Constructor for GrantedLease.

keepAlive

Arguments

:: GrpcClient

Initialized gRPC client.

-> GrantedLease

A previously-granted lease.

-> EtcdQuery LeaseKeepAliveResponse

Keep a lease alive.

Writing.

put

Arguments

:: GrpcClient

initialized gRPC client

-> ByteString

Key.

-> ByteString

Value.

-> Maybe GrantedLease

Lease on the key.

-> EtcdQuery PutResponse

Put one value.

delete

Arguments

:: GrpcClient

Initialized gRPC client.

-> KeyRange

Deleted range.

-> EtcdQuery DeleteRangeResponse

Delete a range of values.

Locking.

data AcquiredLock

Opaque lock.

Show instance used for printing purposes only.

Instances

Show AcquiredLock

Defined in Network.EtcdV3

Methods

showsPrec :: Int -> AcquiredLock -> ShowS

show :: AcquiredLock -> String

showList :: [AcquiredLock] -> ShowS

fromLockResponse :: LockResponse -> AcquiredLock

lock

Arguments

:: GrpcClient

Initialized gRPC client.

-> ByteString

Lock Name

-> GrantedLease

Previously-granted lease that will bound the lifetime of the lock ownership.

-> EtcdQuery LockResponse

unlock

Arguments

:: GrpcClient

Initialized gRPC client.

-> AcquiredLock

Previously-acquired lock.

-> EtcdQuery UnlockResponse

re-exports

def :: Default a => a

The default value for this type.

module Control.Lens