Files
postgrest/src/PostgREST/App.hs
T
steve-chavez 7a7ceaf39a refactor: rename ContentType to MediaType
The core type was wrongly named as the header
2022-07-06 13:47:59 -05:00

648 lines
25 KiB
Haskell

{-|
Module : PostgREST.App
Description : PostgREST main application
This module is in charge of mapping HTTP requests to PostgreSQL queries.
Some of its functionality includes:
- Mapping HTTP request methods to proper SQL statements. For example, a GET request is translated to executing a SELECT query in a read-only TRANSACTION.
- Producing HTTP Headers according to RFCs.
- Content Negotiation
-}
{-# LANGUAGE RecordWildCards #-}
module PostgREST.App
( SignalHandlerInstaller
, SocketRunner
, postgrest
, run
) where
import Control.Monad.Except (liftEither)
import Data.Either.Combinators (mapLeft)
import Data.List (union)
import Data.Maybe (fromJust)
import Data.String (IsString (..))
import Network.Wai.Handler.Warp (defaultSettings, setHost, setPort,
setServerName)
import System.Posix.Types (FileMode)
import qualified Data.ByteString.Char8 as BS
import qualified Data.ByteString.Lazy as LBS
import qualified Data.HashMap.Strict as HM
import qualified Data.Set as S
import qualified Hasql.DynamicStatements.Snippet as SQL (Snippet)
import qualified Hasql.Pool as SQL
import qualified Hasql.Transaction as SQL
import qualified Hasql.Transaction.Sessions as SQL
import qualified Network.HTTP.Types.Header as HTTP
import qualified Network.HTTP.Types.Status as HTTP
import qualified Network.HTTP.Types.URI as HTTP
import qualified Network.Wai as Wai
import qualified Network.Wai.Handler.Warp as Warp
import qualified PostgREST.Admin as Admin
import qualified PostgREST.AppState as AppState
import qualified PostgREST.Auth as Auth
import qualified PostgREST.Cors as Cors
import qualified PostgREST.DbStructure as DbStructure
import qualified PostgREST.Error as Error
import qualified PostgREST.Logger as Logger
import qualified PostgREST.Middleware as Middleware
import qualified PostgREST.OpenAPI as OpenAPI
import qualified PostgREST.Query.QueryBuilder as QueryBuilder
import qualified PostgREST.Query.Statements as Statements
import qualified PostgREST.RangeQuery as RangeQuery
import qualified PostgREST.Request.ApiRequest as ApiRequest
import qualified PostgREST.Request.DbRequestBuilder as ReqBuilder
import PostgREST.AppState (AppState)
import PostgREST.Auth (AuthResult (..))
import PostgREST.Config (AppConfig (..),
LogLevel (..),
OpenAPIMode (..))
import PostgREST.Config.PgVersion (PgVersion (..))
import PostgREST.DbStructure (DbStructure (..))
import PostgREST.DbStructure.Identifiers (FieldName,
QualifiedIdentifier (..),
Schema)
import PostgREST.DbStructure.Proc (ProcDescription (..),
ProcVolatility (..))
import PostgREST.DbStructure.Table (Table (..))
import PostgREST.Error (Error)
import PostgREST.GucHeader (GucHeader,
addHeadersIfNotIncluded,
unwrapGucHeader)
import PostgREST.MediaType (MediaType (..))
import PostgREST.Request.ApiRequest (Action (..),
ApiRequest (..),
InvokeMethod (..),
Mutation (..), Target (..))
import PostgREST.Request.Preferences (PreferCount (..),
PreferParameters (..),
PreferRepresentation (..),
toAppliedHeader)
import PostgREST.Request.QueryParams (QueryParams (..))
import PostgREST.Request.ReadQuery (ReadRequest, fstFieldNames)
import PostgREST.Version (prettyVersion)
import PostgREST.Workers (connectionWorker, listener)
import qualified PostgREST.DbStructure.Proc as Proc
import qualified PostgREST.MediaType as MediaType
import Protolude hiding (Handler)
data RequestContext = RequestContext
{ ctxConfig :: AppConfig
, ctxDbStructure :: DbStructure
, ctxApiRequest :: ApiRequest
, ctxPgVersion :: PgVersion
}
type Handler = ExceptT Error
type DbHandler = Handler SQL.Transaction
type SignalHandlerInstaller = AppState -> IO()
type SocketRunner = Warp.Settings -> Wai.Application -> FileMode -> FilePath -> IO()
run :: SignalHandlerInstaller -> Maybe SocketRunner -> AppState -> IO ()
run installHandlers maybeRunWithSocket appState = do
conf@AppConfig{..} <- AppState.getConfig appState
connectionWorker appState -- Loads the initial DbStructure
installHandlers appState
-- reload schema cache + config on NOTIFY
when configDbChannelEnabled $ listener appState
let app = postgrest configLogLevel appState (connectionWorker appState)
adminApp = Admin.postgrestAdmin appState conf
whenJust configAdminServerPort $ \adminPort -> do
AppState.logWithZTime appState $ "Admin server listening on port " <> show adminPort
void . forkIO $ Warp.runSettings (serverSettings conf & setPort adminPort) adminApp
case configServerUnixSocket of
Just socket ->
-- run the postgrest application with user defined socket. Only for UNIX systems
case maybeRunWithSocket of
Just runWithSocket -> do
AppState.logWithZTime appState $ "Listening on unix socket " <> show socket
runWithSocket (serverSettings conf) app configServerUnixSocketMode socket
Nothing ->
panic "Cannot run with unix socket on non-unix plattforms."
Nothing ->
do
AppState.logWithZTime appState $ "Listening on port " <> show configServerPort
Warp.runSettings (serverSettings conf) app
where
whenJust :: Applicative m => Maybe a -> (a -> m ()) -> m ()
whenJust mg f = maybe (pure ()) f mg
serverSettings :: AppConfig -> Warp.Settings
serverSettings AppConfig{..} =
defaultSettings
& setHost (fromString $ toS configServerHost)
& setPort configServerPort
& setServerName ("postgrest/" <> prettyVersion)
-- | PostgREST application
postgrest :: LogLevel -> AppState.AppState -> IO () -> Wai.Application
postgrest logLevel appState connWorker =
Cors.middleware .
Auth.middleware appState .
Logger.middleware logLevel $
-- fromJust can be used, because the auth middleware will **always** add
-- some AuthResult to the vault.
\req respond -> case fromJust $ Auth.getResult req of
Left err -> respond $ Error.errorResponseFor err
Right authResult -> do
conf <- AppState.getConfig appState
maybeDbStructure <- AppState.getDbStructure appState
pgVer <- AppState.getPgVersion appState
jsonDbS <- AppState.getJsonDbS appState
let
eitherResponse :: IO (Either Error Wai.Response)
eitherResponse =
runExceptT $ postgrestResponse conf maybeDbStructure jsonDbS pgVer (AppState.getPool appState) authResult req
response <- either Error.errorResponseFor identity <$> eitherResponse
-- Launch the connWorker when the connection is down. The postgrest
-- function can respond successfully (with a stale schema cache) before
-- the connWorker is done.
let isPGAway = Wai.responseStatus response == HTTP.status503
when isPGAway connWorker
resp <- addRetryHint isPGAway appState response
respond resp
addRetryHint :: Bool -> AppState -> Wai.Response -> IO Wai.Response
addRetryHint shouldAdd appState response = do
delay <- AppState.getRetryNextIn appState
let h = ("Retry-After", BS.pack $ show delay)
return $ Wai.mapResponseHeaders (\hs -> if shouldAdd then h:hs else hs) response
postgrestResponse
:: AppConfig
-> Maybe DbStructure
-> ByteString
-> PgVersion
-> SQL.Pool
-> AuthResult
-> Wai.Request
-> Handler IO Wai.Response
postgrestResponse conf@AppConfig{..} maybeDbStructure jsonDbS pgVer pool AuthResult{..} req = do
body <- lift $ Wai.strictRequestBody req
dbStructure <-
case maybeDbStructure of
Just dbStructure ->
return dbStructure
Nothing ->
throwError Error.NoSchemaCacheError
apiRequest <-
liftEither . mapLeft Error.ApiRequestError $
ApiRequest.userApiRequest conf dbStructure req body
let handleReq apiReq = handleRequest $ RequestContext conf dbStructure apiReq pgVer
runDbHandler pool (txMode apiRequest) (Just authRole /= configDbAnonRole) configDbPreparedStatements .
Middleware.optionalRollback conf apiRequest $
Middleware.runPgLocals conf authClaims authRole handleReq apiRequest jsonDbS pgVer
runDbHandler :: SQL.Pool -> SQL.Mode -> Bool -> Bool -> DbHandler a -> Handler IO a
runDbHandler pool mode authenticated prepared handler = do
dbResp <-
let transaction = if prepared then SQL.transaction else SQL.unpreparedTransaction in
lift . SQL.use pool . transaction SQL.ReadCommitted mode $ runExceptT handler
resp <-
liftEither . mapLeft Error.PgErr $
mapLeft (Error.PgError authenticated) dbResp
liftEither resp
handleRequest :: RequestContext -> DbHandler Wai.Response
handleRequest context@(RequestContext _ _ ApiRequest{..} _) =
case (iAction, iTarget) of
(ActionRead headersOnly, TargetIdent identifier) ->
handleRead headersOnly identifier context
(ActionMutate MutationCreate, TargetIdent identifier) ->
handleCreate identifier context
(ActionMutate MutationUpdate, TargetIdent identifier) ->
handleUpdate identifier context
(ActionMutate MutationSingleUpsert, TargetIdent identifier) ->
handleSingleUpsert identifier context
(ActionMutate MutationDelete, TargetIdent identifier) ->
handleDelete identifier context
(ActionInfo, TargetIdent identifier) ->
handleInfo identifier context
(ActionInvoke invMethod, TargetProc proc _) ->
handleInvoke invMethod proc context
(ActionInspect headersOnly, TargetDefaultSpec tSchema) ->
handleOpenApi headersOnly tSchema context
(ActionUnknown verb, _) ->
throwError $ Error.UnsupportedVerb verb
_ ->
throwError Error.NotFound
handleRead :: Bool -> QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
handleRead headersOnly identifier context@RequestContext{..} = do
req <- readRequest identifier context
bField <- binaryField context req
let
ApiRequest{..} = ctxApiRequest
AppConfig{..} = ctxConfig
countQuery = QueryBuilder.readRequestToCountQuery req
(tableTotal, queryTotal, _ , body, gucHeaders, gucStatus) <-
lift . SQL.statement mempty $
Statements.createReadStatement
(QueryBuilder.readRequestToQuery req)
(if iPreferCount == Just EstimatedCount then
-- LIMIT maxRows + 1 so we can determine below that maxRows was surpassed
QueryBuilder.limitedQuery countQuery ((+ 1) <$> configDbMaxRows)
else
countQuery
)
(iAcceptMediaType == MTSingularJSON)
(shouldCount iPreferCount)
(iAcceptMediaType == MTTextCSV)
(iAcceptMediaType == MTTextXML)
(iAcceptMediaType == MTGeoJSON)
bField
configDbPreparedStatements
total <- readTotal ctxConfig ctxApiRequest tableTotal countQuery
response <- liftEither $ gucResponse <$> gucStatus <*> gucHeaders
let
(status, contentRange) = RangeQuery.rangeStatusHeader iTopLevelRange queryTotal total
headers =
[ contentRange
, ( "Content-Location"
, "/"
<> toUtf8 (qiName identifier)
<> if BS.null (qsCanonical iQueryParams) then mempty else "?" <> qsCanonical iQueryParams
)
]
++ contentTypeHeaders context
failNotSingular iAcceptMediaType queryTotal . response status headers $
if headersOnly then mempty else LBS.fromStrict body
readTotal :: AppConfig -> ApiRequest -> Maybe Int64 -> SQL.Snippet -> DbHandler (Maybe Int64)
readTotal AppConfig{..} ApiRequest{..} tableTotal countQuery =
case iPreferCount of
Just PlannedCount ->
explain
Just EstimatedCount ->
if tableTotal > (fromIntegral <$> configDbMaxRows) then
max tableTotal <$> explain
else
return tableTotal
_ ->
return tableTotal
where
explain =
lift . SQL.statement mempty . Statements.createExplainStatement countQuery $
configDbPreparedStatements
handleCreate :: QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
handleCreate identifier@QualifiedIdentifier{..} context@RequestContext{..} = do
let
ApiRequest{..} = ctxApiRequest
pkCols = if iPreferRepresentation /= None || isJust iPreferResolution
then maybe mempty tablePKCols $ HM.lookup identifier $ dbTables ctxDbStructure
else mempty
WriteQueryResult{..} <- writeQuery MutationCreate identifier True pkCols context
let
response = gucResponse resGucStatus resGucHeaders
headers =
catMaybes
[ if null resFields then
Nothing
else
Just
( HTTP.hLocation
, "/"
<> toUtf8 qiName
<> HTTP.renderSimpleQuery True (splitKeyValue <$> resFields)
)
, Just . RangeQuery.contentRangeH 1 0 $
if shouldCount iPreferCount then Just resQueryTotal else Nothing
, if null pkCols && isNothing (qsOnConflict iQueryParams) then
Nothing
else
toAppliedHeader <$> iPreferResolution
]
failNotSingular iAcceptMediaType resQueryTotal $
if iPreferRepresentation == Full then
response HTTP.status201 (headers ++ contentTypeHeaders context) (LBS.fromStrict resBody)
else
response HTTP.status201 headers mempty
handleUpdate :: QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
handleUpdate identifier context@RequestContext{..} = do
let
ApiRequest{..} = ctxApiRequest
pkCols = maybe mempty tablePKCols $ HM.lookup identifier $ dbTables ctxDbStructure
WriteQueryResult{..} <- writeQuery MutationUpdate identifier False pkCols context
let
response = gucResponse resGucStatus resGucHeaders
fullRepr = iPreferRepresentation == Full
updateIsNoOp = S.null iColumns
status
| resQueryTotal == 0 && not updateIsNoOp = HTTP.status404
| fullRepr = HTTP.status200
| otherwise = HTTP.status204
contentRangeHeader =
RangeQuery.contentRangeH 0 (resQueryTotal - 1) $
if shouldCount iPreferCount then Just resQueryTotal else Nothing
failChangesOffLimits (RangeQuery.rangeLimit iTopLevelRange) resQueryTotal =<<
failNotSingular iAcceptMediaType resQueryTotal (
if fullRepr then
response status (contentTypeHeaders context ++ [contentRangeHeader]) (LBS.fromStrict resBody)
else
response status [contentRangeHeader] mempty)
handleSingleUpsert :: QualifiedIdentifier -> RequestContext-> DbHandler Wai.Response
handleSingleUpsert identifier context@(RequestContext _ ctxDbStructure ApiRequest{..} _) = do
let pkCols = maybe mempty tablePKCols $ HM.lookup identifier $ dbTables ctxDbStructure
WriteQueryResult{..} <- writeQuery MutationSingleUpsert identifier False pkCols context
let response = gucResponse resGucStatus resGucHeaders
-- Makes sure the querystring pk matches the payload pk
-- e.g. PUT /items?id=eq.1 { "id" : 1, .. } is accepted,
-- PUT /items?id=eq.14 { "id" : 2, .. } is rejected.
-- If this condition is not satisfied then nothing is inserted,
-- check the WHERE for INSERT in QueryBuilder.hs to see how it's done
when (resQueryTotal /= 1) $ do
lift SQL.condemn
throwError Error.PutMatchingPkError
return $
if iPreferRepresentation == Full then
response HTTP.status200 (contentTypeHeaders context) (LBS.fromStrict resBody)
else
response HTTP.status204 [] mempty
handleDelete :: QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
handleDelete identifier context@(RequestContext _ _ ApiRequest{..} _) = do
WriteQueryResult{..} <- writeQuery MutationDelete identifier False mempty context
let
response = gucResponse resGucStatus resGucHeaders
contentRangeHeader =
RangeQuery.contentRangeH 1 0 $
if shouldCount iPreferCount then Just resQueryTotal else Nothing
failChangesOffLimits (RangeQuery.rangeLimit iTopLevelRange) resQueryTotal =<<
failNotSingular iAcceptMediaType resQueryTotal (
if iPreferRepresentation == Full then
response HTTP.status200
(contentTypeHeaders context ++ [contentRangeHeader])
(LBS.fromStrict resBody)
else
response HTTP.status204 [contentRangeHeader] mempty)
handleInfo :: Monad m => QualifiedIdentifier -> RequestContext -> Handler m Wai.Response
handleInfo identifier RequestContext{..} =
case tbl of
Just table ->
return $ Wai.responseLBS HTTP.status200 [allOrigins, allowH table] mempty
Nothing ->
throwError Error.NotFound
where
tbl = HM.lookup identifier (dbTables ctxDbStructure)
allOrigins = ("Access-Control-Allow-Origin", "*")
allowH table =
( HTTP.hAllow
, BS.intercalate "," $
["OPTIONS,GET,HEAD"]
++ ["POST" | tableInsertable table]
++ ["PUT" | tableInsertable table && tableUpdatable table && hasPK]
++ ["PATCH" | tableUpdatable table]
++ ["DELETE" | tableDeletable table]
)
hasPK =
not $ null $ maybe mempty tablePKCols tbl
handleInvoke :: InvokeMethod -> ProcDescription -> RequestContext -> DbHandler Wai.Response
handleInvoke invMethod proc context@RequestContext{..} = do
let
ApiRequest{..} = ctxApiRequest
identifier =
QualifiedIdentifier
(pdSchema proc)
(fromMaybe (pdName proc) $ Proc.procTableName proc)
req <- readRequest identifier context
bField <- binaryField context req
let callReq = ReqBuilder.callRequest proc ctxApiRequest req
(tableTotal, queryTotal, body, gucHeaders, gucStatus) <-
lift . SQL.statement mempty $
Statements.callProcStatement
(Proc.procReturnsScalar proc)
(Proc.procReturnsSingle proc)
(QueryBuilder.requestToCallProcQuery callReq)
(QueryBuilder.readRequestToQuery req)
(QueryBuilder.readRequestToCountQuery req)
(shouldCount iPreferCount)
(iAcceptMediaType == MTSingularJSON)
(iAcceptMediaType == MTTextCSV)
(iAcceptMediaType == MTTextXML)
(iAcceptMediaType == MTGeoJSON)
(iPreferParameters == Just MultipleObjects)
bField
(configDbPreparedStatements ctxConfig)
response <- liftEither $ gucResponse <$> gucStatus <*> gucHeaders
let
(status, contentRange) =
RangeQuery.rangeStatusHeader iTopLevelRange queryTotal tableTotal
failNotSingular iAcceptMediaType queryTotal $
if Proc.procReturnsVoid proc then
response HTTP.status204 [contentRange] mempty
else
response status
(contentTypeHeaders context ++ [contentRange])
(if invMethod == InvHead then mempty else LBS.fromStrict body)
handleOpenApi :: Bool -> Schema -> RequestContext -> DbHandler Wai.Response
handleOpenApi headersOnly tSchema (RequestContext conf@AppConfig{..} dbStructure apiRequest ctxPgVersion) = do
body <-
lift $ case configOpenApiMode of
OAFollowPriv ->
OpenAPI.encode conf dbStructure
<$> SQL.statement [tSchema] (DbStructure.accessibleTables ctxPgVersion configDbPreparedStatements)
<*> SQL.statement tSchema (DbStructure.accessibleProcs ctxPgVersion configDbPreparedStatements)
<*> SQL.statement tSchema (DbStructure.schemaDescription configDbPreparedStatements)
OAIgnorePriv ->
OpenAPI.encode conf dbStructure
(HM.filterWithKey (\(QualifiedIdentifier sch _) _ -> sch == tSchema) $ DbStructure.dbTables dbStructure)
(HM.filterWithKey (\(QualifiedIdentifier sch _) _ -> sch == tSchema) $ DbStructure.dbProcs dbStructure)
<$> SQL.statement tSchema (DbStructure.schemaDescription configDbPreparedStatements)
OADisabled ->
pure mempty
return $
Wai.responseLBS HTTP.status200
(MediaType.toContentType MTOpenAPI : maybeToList (profileHeader apiRequest))
(if headersOnly then mempty else body)
txMode :: ApiRequest -> SQL.Mode
txMode ApiRequest{..} =
case (iAction, iTarget) of
(ActionRead _, _) ->
SQL.Read
(ActionInfo, _) ->
SQL.Read
(ActionInspect _, _) ->
SQL.Read
(ActionInvoke InvGet, _) ->
SQL.Read
(ActionInvoke InvHead, _) ->
SQL.Read
(ActionInvoke InvPost, TargetProc ProcDescription{pdVolatility=Stable} _) ->
SQL.Read
(ActionInvoke InvPost, TargetProc ProcDescription{pdVolatility=Immutable} _) ->
SQL.Read
_ ->
SQL.Write
-- | Result from executing a write query on the database
data WriteQueryResult = WriteQueryResult
{ resQueryTotal :: Int64
, resFields :: [ByteString]
, resBody :: ByteString
, resGucStatus :: Maybe HTTP.Status
, resGucHeaders :: [GucHeader]
}
writeQuery :: Mutation -> QualifiedIdentifier -> Bool -> [Text] -> RequestContext -> DbHandler WriteQueryResult
writeQuery mutation identifier@QualifiedIdentifier{..} isInsert pkCols context@RequestContext{..} = do
readReq <- readRequest identifier context
mutateReq <-
liftEither $
ReqBuilder.mutateRequest mutation qiSchema qiName ctxApiRequest
pkCols
readReq
(_, queryTotal, fields, body, gucHeaders, gucStatus) <-
lift . SQL.statement mempty $
Statements.createWriteStatement
(QueryBuilder.readRequestToQuery readReq)
(QueryBuilder.mutateRequestToQuery mutateReq)
(iAcceptMediaType ctxApiRequest == MTSingularJSON)
isInsert
(iAcceptMediaType ctxApiRequest == MTTextCSV)
(iAcceptMediaType ctxApiRequest == MTGeoJSON)
(iPreferRepresentation ctxApiRequest)
pkCols
(configDbPreparedStatements ctxConfig)
liftEither $ WriteQueryResult queryTotal fields body <$> gucStatus <*> gucHeaders
-- | Response with headers and status overridden from GUCs.
gucResponse
:: Maybe HTTP.Status
-> [GucHeader]
-> HTTP.Status
-> [HTTP.Header]
-> LBS.ByteString
-> Wai.Response
gucResponse gucStatus gucHeaders status headers =
Wai.responseLBS (fromMaybe status gucStatus) $
addHeadersIfNotIncluded headers (map unwrapGucHeader gucHeaders)
-- |
-- Fail a response if a single JSON object was requested and not exactly one
-- was found.
failNotSingular :: MediaType -> Int64 -> Wai.Response -> DbHandler Wai.Response
failNotSingular mediaType queryTotal response =
if mediaType == MTSingularJSON && queryTotal /= 1 then
do
lift SQL.condemn
throwError $ Error.singularityError queryTotal
else
return response
failChangesOffLimits :: Maybe Integer -> Int64 -> Wai.Response -> DbHandler Wai.Response
failChangesOffLimits (Just maxChanges) queryTotal response =
if queryTotal > fromIntegral maxChanges
then do
lift SQL.condemn
throwError $ Error.OffLimitsChangesError queryTotal maxChanges
else
return response
failChangesOffLimits _ _ response = return response
shouldCount :: Maybe PreferCount -> Bool
shouldCount preferCount =
preferCount == Just ExactCount || preferCount == Just EstimatedCount
returnsScalar :: ApiRequest.Target -> Bool
returnsScalar (TargetProc proc _) = Proc.procReturnsScalar proc
returnsScalar _ = False
readRequest :: Monad m => QualifiedIdentifier -> RequestContext -> Handler m ReadRequest
readRequest QualifiedIdentifier{..} (RequestContext AppConfig{..} dbStructure apiRequest _) =
liftEither $
ReqBuilder.readRequest qiSchema qiName configDbMaxRows
(dbRelationships dbStructure)
apiRequest
contentTypeHeaders :: RequestContext -> [HTTP.Header]
contentTypeHeaders RequestContext{..} =
MediaType.toContentType (iAcceptMediaType ctxApiRequest) : maybeToList (profileHeader ctxApiRequest)
-- | If raw(binary) output is requested, check that MediaType is one of the
-- admitted rawMediaTypes and that`?select=...` contains only one field other
-- than `*`
binaryField :: Monad m => RequestContext -> ReadRequest -> Handler m (Maybe FieldName)
binaryField RequestContext{..} readReq
| returnsScalar (iTarget ctxApiRequest) && iAcceptMediaType ctxApiRequest `elem` rawMediaTypes ctxConfig =
return $ Just "pgrst_scalar"
| iAcceptMediaType ctxApiRequest `elem` rawMediaTypes ctxConfig =
let
fldNames = fstFieldNames readReq
fieldName = headMay fldNames
in
if length fldNames == 1 && fieldName /= Just "*" then
return fieldName
else
throwError $ Error.BinaryFieldError (iAcceptMediaType ctxApiRequest)
| otherwise =
return Nothing
rawMediaTypes :: AppConfig -> [MediaType]
rawMediaTypes AppConfig{..} =
(MediaType.decodeMediaType <$> configRawMediaTypes) `union` [MTOctetStream, MTTextPlain, MTTextXML]
profileHeader :: ApiRequest -> Maybe HTTP.Header
profileHeader ApiRequest{..} =
(,) "Content-Profile" <$> (toUtf8 <$> iProfile)
splitKeyValue :: ByteString -> (ByteString, ByteString)
splitKeyValue kv =
(k, BS.tail v)
where
(k, v) = BS.break (== '=') kv