mla310/graphient

GraphQL client for Sangria schemas

GraphQL client for Sangria schemas

Usage:

Add the package to your build:

libraryDependencies += "io.github.erdeszt" %% "graphient" % "1.1.16"
resolvers += Resolver.bintrayRepo("erdeszt", "io.github.erdeszt")

Using the client

import graphient._
import graphient.Implicits._
// Also import your preferred sttp backend

// For the definition of the TestSchema check: graphient/src/test/scala/graphient/TestSchema.scala
val client = new GraphientClient(TestSchema.schema, uri"http://yourapi.com/graphql")

// Using the raw sttp api:
// `request` is a normal sttp request with the body set to the generated graphql query
// and content type set to application/json. You can add authorization or other
// headers before sending the request
// You can also use any type that is circe encodable as the parameters
val request = client.call(Query(TestSchema.Queries.getUser), Params("userId" -> 1L))

// When you are ready, send the request to receive the response. You will need to
// decode the json response.
val response = request.send()

// Using the higher level api (with circe decoding):
case class GetLongResponse(getLong: Long)
implicit val getLongResponseDecoder: Decoder[GetLongResponse] = deriveDecoder[GetLongResponse]

// `responseData` is an Either[List[GraphqlResponseError], GetLongResponse]
// You can add extra headers by passing in a third argument of type `Request[String, Nothing] => Request[String, Nothing]`
// the default is `identity`
val responseData = client.callAndDecode[Params.T, GetLongResponse](Query(TestSchema.Queries.getLong), Params())

Other modes

import graphient._

// Create a query & a variable generator based on some Sangria schema
// For the definition of the TestSchema check: graphient/src/test/scala/graphient/TestSchema.scala
val queryGenerator = new QueryGenerator(TestSchema)
val variableGenerator = new VariableGenerator(TestSchema)

// Generate a query by name
val queryByName = queryGenerator.generateQuery(QueryByName("getUser"))
// or by using the definition
val queryByDefinition = queryGenerator.generateQuery(Query(TestSchema.Qeries.getUser))

// Generate a mutation by name
val mutationByName = queryGenerator.generateQuery(MutationByName("createUser"))
// or by using the definition
val mutationByDefinition = queryGenerator.generateQuery(Mutation(TestSchema.Mutations.get.createUser))

// Generate variables for the query
val variablesForGetUser = variableGenerator.generateVariables(
  QueryByName("getUser"),
  Map[String, Any]("userId" -> 1L)
)
// and for the mutation
val variablesForCreateUser = variableGenerator.generateVariables(
  MutationByName("createUser"),
  Map[String, Any](
    "name"    -> "user 1",
    "age"     -> 26,
    "hobbies" -> List("coding", "debugging")
  )
)

// You can execute the queries in memory using a sangria.execution.Executor:
val result = Executor.execute(
  schema      = TestSchema,
  queryAst    = queryByName.right.toOption.get,
  userContext = context,
  variables   = variablesForGetUser.right.toOption.get
)

// or pretty print it with sangria.renderer.QueryRenderer
val renderedQuery = QueryRenderer.render(mutationByDefinition.right.toOption.get)
// =
// mutation ($name: String!, $age: Int!, $hobbies: [String!]!) {
//   createUser(name: $name, age: $age, hobbies: $hobbies) {
//     id
//     name
//     age
//     hobbies
//   }
// }

// along with the variables using the sangria.marshalling.QueryAstInputUnmarshaller
val unmarshaller = new QueryAstInputUnmarshaller()
val renderedVariables = unmarshaller.render(variablesForCreateUser.right.toOption.get)
// = {name:"user 1",age:26,hobbies:["coding","debugging"]}

For further examples check graphient/src/test/scala/graphient/Worksheet.sc and the specs in grahpeint/src/test and graphient/src/it.