GraphQL HTTP middleware for koa v2,ported from express-graphql,change test framework to ava.
npm install koa-graphql-nextGraphQL HTTP Server Middleware
==============================
Create a GraphQL HTTP server with koa v2. it's ported from express-graphql.
koa-graphql-next have the same api with express-graphql, and well tested like express-graphql,that's mean,and could be try
to using in product currently.
1. only supported koa v2
2. add url to options,and default url is '/graphql'
3. using jest and supertest,instead of mocha in express-graphql.all test from express-graphql (now 64 tests),have been rewrited and passed.
4. ported from express-graphql,for the code,"line by line",and rewrites all the test of express-graphql,so fix many bug founded in tests.
but,thanks for the author of these project:
koa-graphql by chentsulin
graffiti it proveder a middleware for koa v1.
koa-graphql by Arch-Mage
5. for the detail of usage,could read the test,for example how to upload files with graphql.
``sh`
npm install --save koa-graphql-next
Then use koa-graphql-next at any point as a middleware with koa@next:
`js
import graphqlHTTP from 'koa-graphql-next';
const app = new koa();
app.use( graphqlHTTP({
schema: MyGraphQLSchema,
graphiql: true
}));
app.listen(3000);
`
The graphqlHTTP function accepts the following options:
* schema: A GraphQLSchema instance from [graphql-js][].schema
A must be provided.
* context: A value to pass as the context to the graphql()
function from [][].
* rootValue: A value to pass as the rootValue to the graphql()
function from [][].
* pretty: If true, any JSON response will be pretty-printed.
* formatError: An optional function which will be used to format any
errors produced by fulfilling a GraphQL operation. If no function is
provided, GraphQL's default spec-compliant [formatError][] function will
be used.
* validationRules: Optional additional validation rules queries must
satisfy in addition to those defined by the GraphQL spec.
* graphiql: If true, may present [GraphiQL][] when loaded directly
from a browser (a useful tool for debugging and exploration).
* url: added in koa-graphql-next,An optional string for the query url.
default value is '/graphql'.
During development, it's useful to get more information from errors, such as
stack traces. Providing a function to formatError enables this:
`js`
formatError: error => ({
message: error.message,
locations: error.locations,
stack: error.stack
})
Once installed at a path, koa-graphql-next will accept requests with
the parameters:
* query: A string GraphQL document to be executed.
* variables: The runtime values to use for any GraphQL query variables
as a JSON object.
* operationName: If the provided query contains multiple namedquery
operations, this specifies which operation should be executed. If not
provided, a 400 error will be returned if the contains multiple
named operations.
* raw: If the graphiql option is enabled and the raw parameter is
provided raw JSON will always be returned instead of GraphiQL even when
loaded from a browser.
GraphQL will first look for each parameter in the URL's query-string:
`
/graphql?query=query+getUser($id:ID){user(id:$id){name}}&variables={"id":"4"}
If not found in the query-string, it will look in the POST request body.
If a previous middleware has already parsed the POST body, the ctx.request.body
value will be used. Use [][] or a similar middleware to add supportmultipart/form-data
for content, which may be useful for GraphQL mutations
involving uploading files.
If the POST body has not yet been parsed, koa-graphql-next will interpret it
depending on the provided Content-Type header.
* application/json: the POST body will be parsed as a JSON
object of parameters.
* application/x-www-form-urlencoded: this POST body will be
parsed as a url-encoded string of key-value pairs.
* application/graphql: The POST body will be parsed as GraphQL
query string, which provides the query parameter.
[graphql-js]: https://github.com/graphql/graphql-jsformatError`]: https://github.com/graphql/graphql-js/blob/master/src/error/formatError.js
[
[GraphiQL]: https://github.com/graphql/graphiql