chatdesk-ui/postgrest_v12.2.8/src/PostgREST/ApiRequest.hs

338 lines
16 KiB
Haskell

{-|
Module : PostgREST.Request.ApiRequest
Description : PostgREST functions to translate HTTP request to a domain type called ApiRequest.
-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE NamedFieldPuns #-}
-- TODO: This module shouldn't depend on SchemaCache
module PostgREST.ApiRequest
( ApiRequest(..)
, InvokeMethod(..)
, Mutation(..)
, MediaType(..)
, Action(..)
, DbAction(..)
, Payload(..)
, userApiRequest
) where
import qualified Data.Aeson as JSON
import qualified Data.Aeson.Key as K
import qualified Data.Aeson.KeyMap as KM
import qualified Data.ByteString.Char8 as BS
import qualified Data.ByteString.Lazy as LBS
import qualified Data.CaseInsensitive as CI
import qualified Data.Csv as CSV
import qualified Data.HashMap.Strict as HM
import qualified Data.List.NonEmpty as NonEmptyList
import qualified Data.Map.Strict as M
import qualified Data.Set as S
import qualified Data.Text.Encoding as T
import qualified Data.Vector as V
import Data.Either.Combinators (mapBoth)
import Control.Arrow ((***))
import Data.Aeson.Types (emptyArray, emptyObject)
import Data.List (lookup)
import Data.Ranged.Ranges (emptyRange, rangeIntersection,
rangeIsEmpty)
import Network.HTTP.Types.Header (RequestHeaders, hCookie)
import Network.HTTP.Types.URI (parseSimpleQuery)
import Network.Wai (Request (..))
import Network.Wai.Parse (parseHttpAccept)
import Web.Cookie (parseCookies)
import PostgREST.ApiRequest.QueryParams (QueryParams (..))
import PostgREST.ApiRequest.Types (ApiRequestError (..),
RangeError (..))
import PostgREST.Config (AppConfig (..),
OpenAPIMode (..))
import PostgREST.MediaType (MediaType (..))
import PostgREST.RangeQuery (NonnegRange, allRange,
convertToLimitZeroRange,
hasLimitZero,
rangeRequested)
import PostgREST.SchemaCache (SchemaCache (..))
import PostgREST.SchemaCache.Identifiers (FieldName,
QualifiedIdentifier (..),
Schema)
import qualified PostgREST.ApiRequest.Preferences as Preferences
import qualified PostgREST.ApiRequest.QueryParams as QueryParams
import qualified PostgREST.MediaType as MediaType
import Protolude
type RequestBody = LBS.ByteString
data Payload
= ProcessedJSON -- ^ Cached attributes of a JSON payload
{ payRaw :: LBS.ByteString
-- ^ This is the raw ByteString that comes from the request body. We
-- cache this instead of an Aeson Value because it was detected that for
-- large payloads the encoding had high memory usage, see
-- https://github.com/PostgREST/postgrest/pull/1005 for more details
, payKeys :: S.Set Text
-- ^ Keys of the object or if it's an array these keys are guaranteed to
-- be the same across all its objects
}
| ProcessedUrlEncoded { payArray :: [(Text, Text)], payKeys :: S.Set Text }
| RawJSON { payRaw :: LBS.ByteString }
| RawPay { payRaw :: LBS.ByteString }
data InvokeMethod = Inv | InvRead Bool deriving Eq
data Mutation = MutationCreate | MutationDelete | MutationSingleUpsert | MutationUpdate deriving Eq
data Resource
= ResourceRelation Text
| ResourceRoutine Text
| ResourceSchema
data DbAction
= ActRelationRead {dbActQi :: QualifiedIdentifier, actHeadersOnly :: Bool}
| ActRelationMut {dbActQi :: QualifiedIdentifier, actMutation :: Mutation}
| ActRoutine {dbActQi :: QualifiedIdentifier, actInvMethod :: InvokeMethod}
| ActSchemaRead Schema Bool
data Action
= ActDb DbAction
| ActRelationInfo QualifiedIdentifier
| ActRoutineInfo QualifiedIdentifier InvokeMethod
| ActSchemaInfo
{-|
Describes what the user wants to do. This data type is a
translation of the raw elements of an HTTP request into domain
specific language. There is no guarantee that the intent is
sensible, it is up to a later stage of processing to determine
if it is an action we are able to perform.
-}
data ApiRequest = ApiRequest {
iAction :: Action -- ^ Action on the resource
, iRange :: HM.HashMap Text NonnegRange -- ^ Requested range of rows within response
, iTopLevelRange :: NonnegRange -- ^ Requested range of rows from the top level
, iPayload :: Maybe Payload -- ^ Data sent by client and used for mutation actions
, iPreferences :: Preferences.Preferences -- ^ Prefer header values
, iQueryParams :: QueryParams.QueryParams
, iColumns :: S.Set FieldName -- ^ parsed colums from &columns parameter and payload
, iHeaders :: [(ByteString, ByteString)] -- ^ HTTP request headers
, iCookies :: [(ByteString, ByteString)] -- ^ Request Cookies
, iPath :: ByteString -- ^ Raw request path
, iMethod :: ByteString -- ^ Raw request method
, iSchema :: Schema -- ^ The request schema. Can vary depending on profile headers.
, iNegotiatedByProfile :: Bool -- ^ If schema was was chosen according to the profile spec https://www.w3.org/TR/dx-prof-conneg/
, iAcceptMediaType :: [MediaType] -- ^ The resolved media types in the Accept, considering quality(q) factors
, iContentMediaType :: MediaType -- ^ The media type in the Content-Type header
}
-- | Examines HTTP request and translates it into user intent.
userApiRequest :: AppConfig -> Request -> RequestBody -> SchemaCache -> Either ApiRequestError ApiRequest
userApiRequest conf req reqBody sCache = do
resource <- getResource conf $ pathInfo req
(schema, negotiatedByProfile) <- getSchema conf hdrs method
act <- getAction resource schema method
qPrms <- first QueryParamError $ QueryParams.parse (actIsInvokeSafe act) $ rawQueryString req
(topLevelRange, ranges) <- getRanges method qPrms hdrs
(payload, columns) <- getPayload reqBody contentMediaType qPrms act
return $ ApiRequest {
iAction = act
, iRange = ranges
, iTopLevelRange = topLevelRange
, iPayload = payload
, iPreferences = Preferences.fromHeaders (configDbTxAllowOverride conf) (dbTimezones sCache) hdrs
, iQueryParams = qPrms
, iColumns = columns
, iHeaders = iHdrs
, iCookies = iCkies
, iPath = rawPathInfo req
, iMethod = method
, iSchema = schema
, iNegotiatedByProfile = negotiatedByProfile
, iAcceptMediaType = maybe [MTAny] (map MediaType.decodeMediaType . parseHttpAccept) $ lookupHeader "accept"
, iContentMediaType = contentMediaType
}
where
method = requestMethod req
hdrs = requestHeaders req
lookupHeader = flip lookup hdrs
iHdrs = [ (CI.foldedCase k, v) | (k,v) <- hdrs, k /= hCookie]
iCkies = maybe [] parseCookies $ lookupHeader "Cookie"
contentMediaType = maybe MTApplicationJSON MediaType.decodeMediaType $ lookupHeader "content-type"
actIsInvokeSafe x = case x of {ActDb (ActRoutine _ (InvRead _)) -> True; _ -> False}
getResource :: AppConfig -> [Text] -> Either ApiRequestError Resource
getResource AppConfig{configOpenApiMode, configDbRootSpec} = \case
[] -> case configDbRootSpec of
Just (QualifiedIdentifier _ pathName) -> Right $ ResourceRoutine pathName
Nothing | configOpenApiMode == OADisabled -> Left NotFound
| otherwise -> Right ResourceSchema
[table] -> Right $ ResourceRelation table
["rpc", pName] -> Right $ ResourceRoutine pName
_ -> Left NotFound
getAction :: Resource -> Schema -> ByteString -> Either ApiRequestError Action
getAction resource schema method =
case (resource, method) of
(ResourceRoutine rout, "HEAD") -> Right . ActDb $ ActRoutine (qi rout) $ InvRead True
(ResourceRoutine rout, "GET") -> Right . ActDb $ ActRoutine (qi rout) $ InvRead False
(ResourceRoutine rout, "POST") -> Right . ActDb $ ActRoutine (qi rout) Inv
(ResourceRoutine rout, "OPTIONS") -> Right $ ActRoutineInfo (qi rout) $ InvRead True
(ResourceRoutine _, _) -> Left $ InvalidRpcMethod method
(ResourceRelation rel, "HEAD") -> Right . ActDb $ ActRelationRead (qi rel) True
(ResourceRelation rel, "GET") -> Right . ActDb $ ActRelationRead (qi rel) False
(ResourceRelation rel, "POST") -> Right . ActDb $ ActRelationMut (qi rel) MutationCreate
(ResourceRelation rel, "PUT") -> Right . ActDb $ ActRelationMut (qi rel) MutationSingleUpsert
(ResourceRelation rel, "PATCH") -> Right . ActDb $ ActRelationMut (qi rel) MutationUpdate
(ResourceRelation rel, "DELETE") -> Right . ActDb $ ActRelationMut (qi rel) MutationDelete
(ResourceRelation rel, "OPTIONS") -> Right $ ActRelationInfo (qi rel)
(ResourceSchema, "HEAD") -> Right . ActDb $ ActSchemaRead schema True
(ResourceSchema, "GET") -> Right . ActDb $ ActSchemaRead schema False
(ResourceSchema, "OPTIONS") -> Right ActSchemaInfo
_ -> Left $ UnsupportedMethod method
where
qi = QualifiedIdentifier schema
getSchema :: AppConfig -> RequestHeaders -> ByteString -> Either ApiRequestError (Schema, Bool)
getSchema AppConfig{configDbSchemas} hdrs method = do
case profile of
Just p | p `notElem` configDbSchemas -> Left $ UnacceptableSchema $ toList configDbSchemas
| otherwise -> Right (p, True)
Nothing -> Right (defaultSchema, length configDbSchemas /= 1) -- if we have many schemas, assume the default schema was negotiated
where
defaultSchema = NonEmptyList.head configDbSchemas
profile = case method of
-- POST/PATCH/PUT/DELETE don't use the same header as per the spec
"DELETE" -> contentProfile
"PATCH" -> contentProfile
"POST" -> contentProfile
"PUT" -> contentProfile
_ -> acceptProfile
contentProfile = T.decodeUtf8 <$> lookupHeader "Content-Profile"
acceptProfile = T.decodeUtf8 <$> lookupHeader "Accept-Profile"
lookupHeader = flip lookup hdrs
getRanges :: ByteString -> QueryParams -> RequestHeaders -> Either ApiRequestError (NonnegRange, HM.HashMap Text NonnegRange)
getRanges method QueryParams{qsOrder,qsRanges} hdrs
| isInvalidRange = Left $ InvalidRange (if rangeIsEmpty headerRange then LowerGTUpper else NegativeLimit)
| method `elem` ["PATCH", "DELETE"] && not (null qsRanges) && null qsOrder = Left LimitNoOrderError
| method == "PUT" && topLevelRange /= allRange = Left PutLimitNotAllowedError
| otherwise = Right (topLevelRange, ranges)
where
-- According to the RFC (https://www.rfc-editor.org/rfc/rfc9110.html#name-range),
-- the Range header must be ignored for all methods other than GET
headerRange = if method == "GET" then rangeRequested hdrs else allRange
limitRange = fromMaybe allRange (HM.lookup "limit" qsRanges)
headerAndLimitRange = rangeIntersection headerRange limitRange
-- Bypass all the ranges and send only the limit zero range (0 <= x <= -1) if
-- limit=0 is present in the query params (not allowed for the Range header)
ranges = HM.insert "limit" (convertToLimitZeroRange limitRange headerAndLimitRange) qsRanges
-- The only emptyRange allowed is the limit zero range
isInvalidRange = topLevelRange == emptyRange && not (hasLimitZero limitRange)
topLevelRange = fromMaybe allRange $ HM.lookup "limit" ranges -- if no limit is specified, get all the request rows
getPayload :: RequestBody -> MediaType -> QueryParams.QueryParams -> Action -> Either ApiRequestError (Maybe Payload, S.Set FieldName)
getPayload reqBody contentMediaType QueryParams{qsColumns} action = do
checkedPayload <- if shouldParsePayload then payload else Right Nothing
let cols = case (checkedPayload, columns) of
(Just ProcessedJSON{payKeys}, _) -> payKeys
(Just ProcessedUrlEncoded{payKeys}, _) -> payKeys
(Just RawJSON{}, Just cls) -> cls
_ -> S.empty
return (checkedPayload, cols)
where
payload :: Either ApiRequestError (Maybe Payload)
payload = mapBoth InvalidBody Just $ case (contentMediaType, isProc) of
(MTApplicationJSON, _) ->
if isJust columns
then Right $ RawJSON reqBody
else note "All object keys must match" . payloadAttributes reqBody
=<< if LBS.null reqBody && isProc
then Right emptyObject
else first BS.pack $
-- Drop parsing error message in favor of generic one (https://github.com/PostgREST/postgrest/issues/2344)
maybe (Left "Empty or invalid json") Right $ JSON.decode reqBody
(MTTextCSV, _) -> do
json <- csvToJson <$> first BS.pack (CSV.decodeByName reqBody)
note "All lines must have same number of fields" $ payloadAttributes (JSON.encode json) json
(MTUrlEncoded, True) ->
Right $ ProcessedUrlEncoded params (S.fromList $ fst <$> params)
(MTUrlEncoded, False) ->
let paramsMap = HM.fromList $ (identity *** JSON.String) <$> params in
Right $ ProcessedJSON (JSON.encode paramsMap) $ S.fromList (HM.keys paramsMap)
(MTTextPlain, True) -> Right $ RawPay reqBody
(MTTextXML, True) -> Right $ RawPay reqBody
(MTOctetStream, True) -> Right $ RawPay reqBody
(ct, _) -> Left $ "Content-Type not acceptable: " <> MediaType.toMime ct
shouldParsePayload = case action of
ActDb (ActRelationMut _ MutationDelete) -> False
ActDb (ActRelationMut _ _) -> True
ActDb (ActRoutine _ Inv) -> True
_ -> False
columns = case action of
ActDb (ActRelationMut _ MutationCreate) -> qsColumns
ActDb (ActRelationMut _ MutationUpdate) -> qsColumns
ActDb (ActRoutine _ Inv) -> qsColumns
_ -> Nothing
isProc = case action of
ActDb (ActRoutine _ _) -> True
_ -> False
params = (T.decodeUtf8 *** T.decodeUtf8) <$> parseSimpleQuery (LBS.toStrict reqBody)
type CsvData = V.Vector (M.Map Text LBS.ByteString)
{-|
Converts CSV like
a,b
1,hi
2,bye
into a JSON array like
[ {"a": "1", "b": "hi"}, {"a": 2, "b": "bye"} ]
The reason for its odd signature is so that it can compose
directly with CSV.decodeByName
-}
csvToJson :: (CSV.Header, CsvData) -> JSON.Value
csvToJson (_, vals) =
JSON.Array $ V.map rowToJsonObj vals
where
rowToJsonObj = JSON.Object . KM.fromMapText .
M.map (\str ->
if str == "NULL"
then JSON.Null
else JSON.String . T.decodeUtf8 $ LBS.toStrict str
)
payloadAttributes :: RequestBody -> JSON.Value -> Maybe Payload
payloadAttributes raw json =
-- Test that Array contains only Objects having the same keys
case json of
JSON.Array arr ->
case arr V.!? 0 of
Just (JSON.Object o) ->
let canonicalKeys = S.fromList $ K.toText <$> KM.keys o
areKeysUniform = all (\case
JSON.Object x -> S.fromList (K.toText <$> KM.keys x) == canonicalKeys
_ -> False) arr in
if areKeysUniform
then Just $ ProcessedJSON raw canonicalKeys
else Nothing
Just _ -> Nothing
Nothing -> Just emptyPJArray
JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ K.toText <$> KM.keys o)
-- truncate everything else to an empty array.
_ -> Just emptyPJArray
where
emptyPJArray = ProcessedJSON (JSON.encode emptyArray) S.empty