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Diffstat (limited to 'docs/tutorial/test.hs')
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1 files changed, 0 insertions, 55 deletions
diff --git a/docs/tutorial/test.hs b/docs/tutorial/test.hs deleted file mode 100644 index 631407c..0000000 --- a/docs/tutorial/test.hs +++ /dev/null @@ -1,55 +0,0 @@ -{-# LANGUAGE OverloadedStrings #-} - -import qualified Data.Aeson as Aeson -import qualified Data.ByteString.Lazy.Char8 as ByteString.Lazy.Char8 -import qualified Data.HashMap.Strict as HashMap -import Language.GraphQL -import Language.GraphQL.Type -import qualified Language.GraphQL.Type.Out as Out - --- GraphQL supports 3 kinds of operations: queries, mutations and subscriptions. --- Our first schema supports only queries. -citeSchema :: Schema IO -citeSchema = schema queryType - --- GraphQL distinguishes between input and output types. Input types are field --- argument types and they are defined in Language.GraphQL.Type.In. Output types --- are result types, they are defined in Language.GraphQL.Type.Out. Root types --- are always object types. --- --- Here we define a type "Query". The second argument is an optional --- description, the third one is the list of interfaces implemented by the --- object type. The last argument is a field map. Keys are field names, values --- are field definitions and resolvers. Resolvers are the functions, where the --- actual logic lives, they return values for the respective fields. -queryType :: Out.ObjectType IO -queryType = Out.ObjectType "Query" (Just "Root Query type.") [] - $ HashMap.singleton "cite" citeResolver - where - -- 'ValueResolver' is a 'Resolver' data constructor, it combines a field - -- definition with its resolver function. This function resolves a value for - -- a field (as opposed to the 'EventStreamResolver' used by subscriptions). - -- Our resolver just returns a constant value. - citeResolver = ValueResolver citeField - $ pure "Piscis primum a capite foetat" - - -- The first argument is an optional field description. The second one is - -- the field type and the third one is for arguments (we have none in this - -- example). - -- - -- GraphQL has named and wrapping types. String is a scalar, named type. - -- Named types are nullable by default. To make our "cite" field - -- non-nullable, we wrap it in the wrapping type, Non-Null. - citeField = Out.Field - (Just "Provides a cite.") (Out.NonNullScalarType string) HashMap.empty - --- Now we can execute a query. Since our schema defines only one field, --- everything we can do is to ask to resolve it and give back the result. --- Since subscriptions don't return plain values, the 'graphql' function returns --- an 'Either'. 'Left' is for subscriptions, 'Right' is for queries and --- mutations. -main :: IO () -main = do - Right result <- graphql citeSchema "{ cite }" - ByteString.Lazy.Char8.putStrLn $ Aeson.encode result - |
