Safe Haskell	None
Language	Haskell2010

Hasura.GraphQL.Execute.Subscription.Poll.Common

Description

Multiplexed subscription poller threads; see Hasura.GraphQL.Execute.Subscription for details.

Synopsis

newtype SubscriberId = SubscriberId {
- unSubscriberId :: UUID
}
newSubscriberId :: IO SubscriberId
newtype SubscriberMetadata = SubscriberMetadata {
- unSubscriberMetadata :: Value
}
mkSubscriberMetadata :: WSId -> OperationId -> Maybe OperationName -> RequestId -> SubscriberMetadata
data Subscriber = Subscriber {
- _sId :: !SubscriberId
- _sMetadata :: !SubscriberMetadata
- _sRequestId :: !RequestId
- _sOperationName :: !(Maybe OperationName)
- _sOnChangeCallback :: !OnChange
}
data SubscriptionMetadata = SubscriptionMetadata {
- _sqmExecutionTime :: !DiffTime
}
data SubscriptionResponse = SubscriptionResponse {
- _lqrPayload :: !ByteString
- _lqrExecutionTime :: !DiffTime
}
type SubscriptionGQResponse = GQResult SubscriptionResponse
type OnChange = SubscriptionGQResponse -> IO ()
type SubscriberMap = TMap SubscriberId Subscriber
data Cohort streamCursorVars = Cohort {
- _cCohortId :: !CohortId
- _cPreviousResponse :: !(TVar (Maybe ResponseHash))
- _cExistingSubscribers :: !SubscriberMap
- _cNewSubscribers :: !SubscriberMap
- _cStreamCursorVariables :: !streamCursorVars
}
newtype BatchId = BatchId {
- _unBatchId :: Int
}
newtype ResponseHash = ResponseHash {
- unResponseHash :: Digest Blake2b_256
}
mkRespHash :: ByteString -> ResponseHash
type CohortKey = CohortVariables
type CohortMap streamCursor = TMap CohortKey (Cohort streamCursor)
dumpCohortMap :: CohortMap streamCursor -> IO Value
data CohortSnapshot = CohortSnapshot {
- _csVariables :: !CohortVariables
- _csPreviousResponse :: !(TVar (Maybe ResponseHash))
- _csExistingSubscribers :: ![Subscriber]
- _csNewSubscribers :: ![Subscriber]
}
data Poller streamCursor = Poller {
- _pCohorts :: !(CohortMap streamCursor)
- _pIOState :: !(TMVar PollerIOState)
}
data PollerIOState = PollerIOState {
- _pThread :: !Thread
- _pId :: !PollerId
}
data PollerKey = PollerKey {
- _lgSource :: !SourceName
- _lgRole :: !RoleName
- _lgQuery :: !Text
}
type PollerMap streamCursor = Map PollerKey (Poller streamCursor)
dumpPollerMap :: Bool -> PollerMap streamCursor -> IO Value
newtype PollerId = PollerId {
- unPollerId :: UUID
}
data SubscriberExecutionDetails = SubscriberExecutionDetails {
- _sedSubscriberId :: !SubscriberId
- _sedSubscriberMetadata :: !SubscriberMetadata
}
data CohortExecutionDetails = CohortExecutionDetails {
- _cedCohortId :: !CohortId
- _cedVariables :: !CohortVariables
- _cedResponseSize :: !(Maybe Int)
- _cedPushedTo :: ![SubscriberExecutionDetails]
- _cedIgnored :: ![SubscriberExecutionDetails]
- _cedBatchId :: !BatchId
}
data BatchExecutionDetails = BatchExecutionDetails {
- _bedPgExecutionTime :: !DiffTime
- _bedPushTime :: !DiffTime
- _bedBatchId :: !BatchId
- _bedCohorts :: ![CohortExecutionDetails]
- _bedBatchResponseSizeBytes :: !(Maybe Int)
}
batchExecutionDetailMinimal :: BatchExecutionDetails -> Value
data PollDetails = PollDetails {
- _pdPollerId :: !PollerId
- _pdGeneratedSql :: !Text
- _pdSnapshotTime :: !DiffTime
- _pdBatches :: ![BatchExecutionDetails]
- _pdTotalTime :: !DiffTime
- _pdLiveQueryOptions :: !SubscriptionsOptions
- _pdSource :: !SourceName
- _pdRole :: !RoleName
- _pdParameterizedQueryHash :: !ParameterizedQueryHash
}
pollDetailMinimal :: PollDetails -> Value
type SubscriptionPostPollHook = PollDetails -> IO ()
defaultSubscriptionPostPollHook :: Logger Hasura -> SubscriptionPostPollHook

Documentation

newtype SubscriberId Source #

Constructors

SubscriberId
Fields unSubscriberId :: UUID

Instances

Instances details

Eq SubscriberId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: SubscriberId -> SubscriberId -> Bool # (/=) :: SubscriberId -> SubscriberId -> Bool #
Show SubscriberId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> SubscriberId -> ShowS # show :: SubscriberId -> String # showList :: [SubscriberId] -> ShowS #
Generic SubscriberId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Associated Types type Rep SubscriberId :: Type -> Type # Methods from :: SubscriberId -> Rep SubscriberId x # to :: Rep SubscriberId x -> SubscriberId #
Hashable SubscriberId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods hashWithSalt :: Int -> SubscriberId -> Int hash :: SubscriberId -> Int
ToJSON SubscriberId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toJSON :: SubscriberId -> Value toEncoding :: SubscriberId -> Encoding toJSONList :: [SubscriberId] -> Value toEncodingList :: [SubscriberId] -> Encoding
type Rep SubscriberId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common type Rep SubscriberId = D1 ('MetaData "SubscriberId" "Hasura.GraphQL.Execute.Subscription.Poll.Common" "graphql-engine-1.0.0-inplace" 'True) (C1 ('MetaCons "SubscriberId" 'PrefixI 'True) (S1 ('MetaSel ('Just "unSubscriberId") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 UUID)))

newSubscriberId :: IO SubscriberId Source #

newtype SubscriberMetadata Source #

Allows a user of the live query subsystem (currently websocket transport) to attach arbitrary metadata about a subscriber. This information is available as part of Subscriber in CohortExecutionDetails and can be logged by customizing in pollerlog

Constructors

SubscriberMetadata
Fields unSubscriberMetadata :: Value

Instances

Instances details

Eq SubscriberMetadata Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: SubscriberMetadata -> SubscriberMetadata -> Bool # (/=) :: SubscriberMetadata -> SubscriberMetadata -> Bool #
Show SubscriberMetadata Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> SubscriberMetadata -> ShowS # show :: SubscriberMetadata -> String # showList :: [SubscriberMetadata] -> ShowS #
ToJSON SubscriberMetadata Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toJSON :: SubscriberMetadata -> Value toEncoding :: SubscriberMetadata -> Encoding toJSONList :: [SubscriberMetadata] -> Value toEncodingList :: [SubscriberMetadata] -> Encoding

mkSubscriberMetadata :: WSId -> OperationId -> Maybe OperationName -> RequestId -> SubscriberMetadata Source #

data Subscriber Source #

Constructors

Subscriber
Fields _sId :: !SubscriberId _sMetadata :: !SubscriberMetadata _sRequestId :: !RequestId _sOperationName :: !(Maybe OperationName) _sOnChangeCallback :: !OnChange

data SubscriptionMetadata Source #

Subscription onChange metadata, used for adding more extra analytics data

Constructors

SubscriptionMetadata
Fields _sqmExecutionTime :: !DiffTime

data SubscriptionResponse Source #

Constructors

SubscriptionResponse
Fields _lqrPayload :: !ByteString _lqrExecutionTime :: !DiffTime

type SubscriptionGQResponse = GQResult SubscriptionResponse Source #

type OnChange = SubscriptionGQResponse -> IO () Source #

type SubscriberMap = TMap SubscriberId Subscriber Source #

data Cohort streamCursorVars Source #

A batched group of Subscribers who are not only listening to the same query but also have identical session and query variables. Each result pushed to a Cohort is forwarded along to each of its Subscribers.

In SQL, each Cohort corresponds to a single row in the laterally-joined _subs table (and therefore a single row in the query result).

Instances

Instances details

Eq BatchId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: BatchId -> BatchId -> Bool # (/=) :: BatchId -> BatchId -> Bool #
Show BatchId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> BatchId -> ShowS # show :: BatchId -> String # showList :: [BatchId] -> ShowS #
ToJSON BatchId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toJSON :: BatchId -> Value toEncoding :: BatchId -> Encoding toJSONList :: [BatchId] -> Value toEncodingList :: [BatchId] -> Encoding

newtype ResponseHash Source #

A hash used to determine if the result changed without having to keep the entire result in memory. Using a cryptographic hash ensures that a hash collision is almost impossible: with 256 bits, even if a subscription changes once per second for an entire year, the probability of a hash collision is ~4.294417×10-63. See Note [Blake2b faster than SHA-256].

Constructors

ResponseHash
Fields unResponseHash :: Digest Blake2b_256

Instances

Instances details

Eq ResponseHash Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: ResponseHash -> ResponseHash -> Bool # (/=) :: ResponseHash -> ResponseHash -> Bool #
Show ResponseHash Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> ResponseHash -> ShowS # show :: ResponseHash -> String # showList :: [ResponseHash] -> ShowS #
ToJSON ResponseHash Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toJSON :: ResponseHash -> Value toEncoding :: ResponseHash -> Encoding toJSONList :: [ResponseHash] -> Value toEncodingList :: [ResponseHash] -> Encoding

mkRespHash :: ByteString -> ResponseHash Source #

type CohortKey = CohortVariables Source #

A key we use to determine if two Subscribers belong in the same Cohort (assuming they already meet the criteria to be in the same Poller). Note the distinction between this and CohortId; the latter is a completely synthetic key used only to identify the cohort in the generated SQL query.

type CohortMap streamCursor = TMap CohortKey (Cohort streamCursor) Source #

This has the invariant, maintained in removeLiveQuery, that it contains no Cohort with zero total (existing + new) subscribers.

dumpCohortMap :: CohortMap streamCursor -> IO Value Source #

data CohortSnapshot Source #

Constructors

CohortSnapshot
Fields _csVariables :: !CohortVariables _csPreviousResponse :: !(TVar (Maybe ResponseHash)) _csExistingSubscribers :: ![Subscriber] _csNewSubscribers :: ![Subscriber]

data Poller streamCursor Source #

A unique, multiplexed query. Each Poller has its own polling thread that periodically polls Postgres and pushes results to each of its listening Cohorts.

In SQL, an Poller corresponds to a single, multiplexed query, though in practice, Pollers with large numbers of Cohorts are batched into multiple concurrent queries for performance reasons.

Constructors

Poller

Fields

_pCohorts :: !(CohortMap streamCursor)
_pIOState :: !(TMVar PollerIOState)
This is in a separate TMVar because it’s important that we are able to construct Poller values in STM --- we need the insertion into the PollerMap to be atomic to ensure that we don’t accidentally create two for the same query due to a race. However, we can’t spawn the worker thread or create the metrics store in STM, so we insert it into the Poller only after we’re certain we won’t create any duplicates.
This var is "write once", moving monotonically from empty to full. TODO this could probably be tightened up to something like 'STM PollerIOState'

data PollerIOState Source #

Constructors

PollerIOState
Fields _pThread :: !Thread a handle on the poller’s worker thread that can be used to `stop` it if all its cohorts stop listening _pId :: !PollerId

data PollerKey Source #

Constructors

PollerKey
Fields _lgSource :: !SourceName _lgRole :: !RoleName _lgQuery :: !Text

Instances

Instances details

Eq PollerKey Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: PollerKey -> PollerKey -> Bool # (/=) :: PollerKey -> PollerKey -> Bool #
Show PollerKey Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> PollerKey -> ShowS # show :: PollerKey -> String # showList :: [PollerKey] -> ShowS #
Generic PollerKey Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Associated Types type Rep PollerKey :: Type -> Type # Methods from :: PollerKey -> Rep PollerKey x # to :: Rep PollerKey x -> PollerKey #
Hashable PollerKey Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods hashWithSalt :: Int -> PollerKey -> Int hash :: PollerKey -> Int
ToJSON PollerKey Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toJSON :: PollerKey -> Value toEncoding :: PollerKey -> Encoding toJSONList :: [PollerKey] -> Value toEncodingList :: [PollerKey] -> Encoding
type Rep PollerKey Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common type Rep PollerKey = D1 ('MetaData "PollerKey" "Hasura.GraphQL.Execute.Subscription.Poll.Common" "graphql-engine-1.0.0-inplace" 'False) (C1 ('MetaCons "PollerKey" 'PrefixI 'True) (S1 ('MetaSel ('Just "_lgSource") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 SourceName) :: (S1 ('MetaSel ('Just "_lgRole") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 RoleName) :: S1 ('MetaSel ('Just "_lgQuery") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Text))))

type PollerMap streamCursor = Map PollerKey (Poller streamCursor) Source #

dumpPollerMap :: Bool -> PollerMap streamCursor -> IO Value Source #

newtype PollerId Source #

An ID to track unique Pollers, so that we can gather metrics about each poller

Constructors

PollerId
Fields unPollerId :: UUID

Instances

Instances details

Eq PollerId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: PollerId -> PollerId -> Bool # (/=) :: PollerId -> PollerId -> Bool #
Show PollerId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> PollerId -> ShowS # show :: PollerId -> String # showList :: [PollerId] -> ShowS #
Generic PollerId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Associated Types type Rep PollerId :: Type -> Type # Methods from :: PollerId -> Rep PollerId x # to :: Rep PollerId x -> PollerId #
ToJSON PollerId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toJSON :: PollerId -> Value toEncoding :: PollerId -> Encoding toJSONList :: [PollerId] -> Value toEncodingList :: [PollerId] -> Encoding
type Rep PollerId Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common type Rep PollerId = D1 ('MetaData "PollerId" "Hasura.GraphQL.Execute.Subscription.Poll.Common" "graphql-engine-1.0.0-inplace" 'True) (C1 ('MetaCons "PollerId" 'PrefixI 'True) (S1 ('MetaSel ('Just "unPollerId") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 UUID)))

data SubscriberExecutionDetails Source #

Constructors

SubscriberExecutionDetails
Fields _sedSubscriberId :: !SubscriberId _sedSubscriberMetadata :: !SubscriberMetadata

Instances

Instances details

Eq SubscriberExecutionDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: SubscriberExecutionDetails -> SubscriberExecutionDetails -> Bool # (/=) :: SubscriberExecutionDetails -> SubscriberExecutionDetails -> Bool #
Show SubscriberExecutionDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> SubscriberExecutionDetails -> ShowS # show :: SubscriberExecutionDetails -> String # showList :: [SubscriberExecutionDetails] -> ShowS #

data CohortExecutionDetails Source #

Execution information related to a cohort on a poll cycle

Constructors

CohortExecutionDetails

Fields

_cedCohortId :: !CohortId
_cedVariables :: !CohortVariables
_cedResponseSize :: !(Maybe Int)
Nothing in case of an error
_cedPushedTo :: ![SubscriberExecutionDetails]
The response on this cycle has been pushed to these above subscribers New subscribers (those which haven't been around during the previous poll cycle) will always be part of this
_cedIgnored :: ![SubscriberExecutionDetails]
The response on this cycle has *not* been pushed to these above subscribers. This would when the response hasn't changed from the previous polled cycle
_cedBatchId :: !BatchId

Instances

Instances details

Eq CohortExecutionDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: CohortExecutionDetails -> CohortExecutionDetails -> Bool # (/=) :: CohortExecutionDetails -> CohortExecutionDetails -> Bool #
Show CohortExecutionDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> CohortExecutionDetails -> ShowS # show :: CohortExecutionDetails -> String # showList :: [CohortExecutionDetails] -> ShowS #

data BatchExecutionDetails Source #

Execution information related to a single batched execution

Constructors

BatchExecutionDetails
Fields _bedPgExecutionTime :: !DiffTime postgres execution time of each batch _bedPushTime :: !DiffTime time to taken to push to all cohorts belonging to this batch _bedBatchId :: !BatchId id of the batch _bedCohorts :: ![CohortExecutionDetails] execution details of the cohorts belonging to this batch _bedBatchResponseSizeBytes :: !(Maybe Int)

Instances

Instances details

Eq BatchExecutionDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: BatchExecutionDetails -> BatchExecutionDetails -> Bool # (/=) :: BatchExecutionDetails -> BatchExecutionDetails -> Bool #
Show BatchExecutionDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> BatchExecutionDetails -> ShowS # show :: BatchExecutionDetails -> String # showList :: [BatchExecutionDetails] -> ShowS #

batchExecutionDetailMinimal :: BatchExecutionDetails -> Value Source #

see Note [Minimal LiveQuery Poller Log]

data PollDetails Source #

Constructors

PollDetails

Fields

_pdPollerId :: !PollerId
the unique ID (basically a thread that run as a Poller) for the Poller
_pdGeneratedSql :: !Text
the multiplexed SQL query to be run against the database with all the variables together
_pdSnapshotTime :: !DiffTime
the time taken to get a snapshot of cohorts from our SubscriptionsState data structure
_pdBatches :: ![BatchExecutionDetails]
list of execution batches and their details
_pdTotalTime :: !DiffTime
total time spent on a poll cycle
_pdLiveQueryOptions :: !SubscriptionsOptions
_pdSource :: !SourceName
_pdRole :: !RoleName
_pdParameterizedQueryHash :: !ParameterizedQueryHash

Instances

Instances details

Eq PollDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods (==) :: PollDetails -> PollDetails -> Bool # (/=) :: PollDetails -> PollDetails -> Bool #
Show PollDetails Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods showsPrec :: Int -> PollDetails -> ShowS # show :: PollDetails -> String # showList :: [PollDetails] -> ShowS #
ToEngineLog PollDetails Hasura Source #
Instance details Defined in Hasura.GraphQL.Execute.Subscription.Poll.Common Methods toEngineLog :: PollDetails -> (LogLevel, EngineLogType Hasura, Value) Source #

pollDetailMinimal :: PollDetails -> Value Source #

see Note [Minimal LiveQuery Poller Log]

type SubscriptionPostPollHook = PollDetails -> IO () Source #

defaultSubscriptionPostPollHook :: Logger Hasura -> SubscriptionPostPollHook Source #