获取 GraphQL 整体模式查询

You can use GraphQL-JS's introspection query to get everything you'd like to know about the schema:

import { introspectionQuery } from 'graphql';

If you want just the information for types, you can use this:

{
__schema: {
types: {
...fullType
}
}
}

Which uses the following fragment from the introspection query:

fragment FullType on __Type {
kind
name
description
fields(includeDeprecated: true) {
name
description
args {
...InputValue
}
type {
...TypeRef
}
isDeprecated
deprecationReason
}
inputFields {
...InputValue
}
interfaces {
...TypeRef
}
enumValues(includeDeprecated: true) {
name
description
isDeprecated
deprecationReason
}
possibleTypes {
...TypeRef
}
}
fragment InputValue on __InputValue {
name
description
type { ...TypeRef }
defaultValue
}
fragment TypeRef on __Type {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
}
}
}
}
}
}
}
}
`;

If that seems complicated, it's because fields can be arbitrarility deeply wrapped in nonNulls and Lists, which means that technically even the query above does not reflect the full schema if your fields are wrapped in more than 7 layers (which probably isn't the case).

You can see the source code for introspectionQuery here.

Update

Using graphql-cli is now the recommended workflow to get and update your schema.

The following commands will get you started:

# install via NPM
npm install -g graphql-cli


# Setup your .graphqlconfig file (configure endpoints + schema path)
graphql init


# Download the schema from the server
graphql get-schema

You can even listen for schema changes and continuously update your schema by running:

graphql get-schema --watch

In case you just want to download the GraphQL schema, use the following approach:

The easiest way to get a GraphQL schema is using the CLI tool get-graphql-schema.

You can install it via NPM:

npm install -g get-graphql-schema

There are two ways to get your schema. 1) GraphQL IDL format or 2) JSON introspection query format.

GraphQL IDL format

get-graphql-schema ENDPOINT_URL > schema.graphql

JSON introspection format

get-graphql-schema ENDPOINT_URL --json > schema.json

or

get-graphql-schema ENDPOINT_URL -j > schema.json

For more information you can refer to the following tutorial: How to download the GraphQL IDL Schema

If you want to do it by your self, read these code:

There is a modular state-of-art tool 「graphql-cli」, consider looking at it. It uses package 「graphql」's buildClientSchema to build IDL .graphql file from introspection data.

• graphql-cli get-schema :integrated into graphql-cli part 1
• graphql-config EndpointsExtension :integrated into graphql-cli part 2

This is the query that GraphiQL uses (network capture):

query IntrospectionQuery {
__schema {
queryType {
name
}
mutationType {
name
}
subscriptionType {
name
}
types {
...FullType
}
directives {
name
description
locations
args {
...InputValue
}
}
}
}


fragment FullType on __Type {
kind
name
description
fields(includeDeprecated: true) {
name
description
args {
...InputValue
}
type {
...TypeRef
}
isDeprecated
deprecationReason
}
inputFields {
...InputValue
}
interfaces {
...TypeRef
}
enumValues(includeDeprecated: true) {
name
description
isDeprecated
deprecationReason
}
possibleTypes {
...TypeRef
}
}


fragment InputValue on __InputValue {
name
description
type {
...TypeRef
}
defaultValue
}


fragment TypeRef on __Type {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
}
}
}
}
}
}
}
}

You can download a remote GraphQL server's schema with the following command. When the command succeeds, you should see a new file named schema.json in the current working directory.

~$ npx apollo-cli download-schema $GRAPHQL_URL --output schema.json

You can use IntelliJ plugin JS GraphQL then IDEA will ask you create two files "graphql.config.json" and "graphql.schema.json"

Then you can edit "graphql.config.json" to point to your local or remote GraphQL server:

"schema": {
"README_request" : "To request the schema from a url instead, remove the 'file' JSON property above (and optionally delete the default graphql.schema.json file).",
"request": {
"url" : "http://localhost:4000",
"method" : "POST",
"README_postIntrospectionQuery" : "Whether to POST an introspectionQuery to the url. If the url always returns the schema JSON, set to false and consider using GET",
"postIntrospectionQuery" : true,
"README_options" : "See the 'Options' section at https://github.com/then/then-request",
"options" : {
"headers": {
"user-agent" : "JS GraphQL"
}
}
}

After that IDEA plugin will auto load schema from GraphQL server and show the schema json in the console like this:

Loaded schema from 'http://localhost:4000': {"data":{"__schema":{"queryType":{"name":"Query"},"mutationType":{"name":"Mutation"},"subscriptionType":null,"types":[{"kind":"OBJECT","name":"Query","description":"","fields":[{"name":"launche

You could use apollo codegen:client. See https://github.com/apollographql/apollo-tooling#apollo-clientcodegen-output

Using apollo cli:

npx apollo schema:download --endpoint=http://localhost:4000/graphql schema.json

Refer to https://stackoverflow.com/a/42010467/10189759

Would like to point out that if authentications are needed, that you probably cannot just use the config file generated from graphql init

You might have to do something like this, for example, using the github graphql API

{
"projects": {
"graphqlProjectTestingGraphql": {
"schemaPath": "schema.graphql",
"extensions": {
"endpoints": {
"dev": {
"url": "https://api.github.com/graphql",
"headers": {
"Authorization": "Bearer <Your token here>"
}
}
}
}
}
}
}

You can use the Hasura's graphqurl utility

npm install -g graphqurl


gq <endpoint> --introspect > schema.graphql


# or if you want it in json
gq <endpoint> --introspect --format json > schema.json

Full documentation: https://github.com/hasura/graphqurl

You can use GraphQL-Codegen with the ast-plugin

npm install --save graphql
npm install --save-dev @graphql-codegen/cli
npx graphql-codegen init

Follow the steps to generate the codegen.yml file

Once the tool is installed, you can use the plugin to download the schema which is schema-ast

The best is to follow the instruction on the page to install it… but basically:

npm install --save-dev @graphql-codegen/schema-ast

Then configure the codegen.yml file to set which schema(s) is/are the source of truth and where to put the downloaded schema(s) file:

schema:
- 'http://localhost:3000/graphql'
generates:
path/to/file.graphql:
plugins:
- schema-ast
config:
includeDirectives: true

Update

After getting sick of modifying my previous script all the time, I caved and made my own CLI tool gql-sdl. I still can't find a different tool that can download GraphQL SDL with zero config but would love for one to exist.

Basic usage:

$ gql-sdl https://api.github.com/graphql -H "Authorization: Bearer ghp_[redacted]"
directive @requiredCapabilities(requiredCapabilities: [String!]) on OBJECT | SCALAR | ARGUMENT_DEFINITION | INTERFACE | INPUT_OBJECT | FIELD_DEFINITION | ENUM | ENUM_VALUE | UNION | INPUT_FIELD_DEFINITION


"""Autogenerated input type of AbortQueuedMigrations"""
input AbortQueuedMigrationsInput {
"""The ID of the organization that is running the migrations."""
ownerId: ID!


"""A unique identifier for the client performing the mutation."""
clientMutationId: String
}
...

The header argument -H is technically optional but most GraphQL APIs require authentication via headers. You can also download the JSON response instead (--json) but that's a use case already well served by other tools.

Under the hood this still uses the introspection query provided by GraphQL.js, so if you're looking to incorporate this functionality into your own code see the example below.

Previous answer

Somehow I wasn't able to get any of the suggested CLI tools to output the schema in GraphQL's Schema Definition Language (SDL) instead of the introspection result JSON. I ended up throwing together a really quick Node script to make the GraphQL library do it for me:

const fs = require("fs");
const { buildClientSchema, getIntrospectionQuery, printSchema } = require("graphql");
const fetch = require("node-fetch");


async function saveSchema(endpoint, filename) {
const response = await fetch(endpoint, {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({ query: getIntrospectionQuery() })
});
const graphqlSchemaObj = buildClientSchema((await response.json()).data);
const sdlString = printSchema(graphqlSchemaObj);
fs.writeFileSync(filename, sdlString);
}


saveSchema("https://example.com/graphql", "schema.graphql");

getIntrospectionQuery() has the complete introspection query you need to get everything, and then buildClientSchema() and printSchema() turns the JSON mess into GraphQL SDL.

Wouldn't be too difficult to make this into a CLI tool itself but that feels like overkill.

I was also looking and came across this Medium article on GraphQL

The below query returned many details regarding schema, queries and their input & output params type.

fragment FullType on __Type {
kind
name
fields(includeDeprecated: true) {
name
args {
...InputValue
}
type {
...TypeRef
}
isDeprecated
deprecationReason
}
inputFields {
...InputValue
}
interfaces {
...TypeRef
}
enumValues(includeDeprecated: true) {
name
isDeprecated
deprecationReason
}
possibleTypes {
...TypeRef
}
}
fragment InputValue on __InputValue {
name
type {
...TypeRef
}
defaultValue
}
fragment TypeRef on __Type {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
}
}
}
}
}
}
}
}
query IntrospectionQuery {
__schema {
queryType {
name
}
mutationType {
name
}
types {
...FullType
}
directives {
name
locations
args {
...InputValue
}
}
}
}

The graphql npm package's IntrospectionQuery does

query IntrospectionQuery {
__schema {
queryType {
name
}
mutationType {
name
}
subscriptionType {
name
}
types {
...FullType
}
directives {
name
description


locations
args {
...InputValue
}
}
}
}


fragment FullType on __Type {
kind
name
description


fields(includeDeprecated: true) {
name
description
args {
...InputValue
}
type {
...TypeRef
}
isDeprecated
deprecationReason
}
inputFields {
...InputValue
}
interfaces {
...TypeRef
}
enumValues(includeDeprecated: true) {
name
description
isDeprecated
deprecationReason
}
possibleTypes {
...TypeRef
}
}


fragment InputValue on __InputValue {
name
description
type {
...TypeRef
}
defaultValue
}


fragment TypeRef on __Type {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
ofType {
kind
name
}
}
}
}
}
}
}
}

source