graphql-language-service

What is graphql-language-service?

The graphql-language-service npm package provides a set of tools and utilities for working with GraphQL language features. It includes functionalities such as parsing, validation, and autocompletion, which are essential for building GraphQL development tools and editors.

What are graphql-language-service's main functionalities?

Parsing

This feature allows you to parse a GraphQL query string into an Abstract Syntax Tree (AST). The AST can then be used for further analysis or transformation.

const { parse } = require('graphql-language-service-parser');
const query = `query { user(id: 1) { name } }`;
const ast = parse(query);
console.log(JSON.stringify(ast, null, 2));

Validation

This feature allows you to validate a GraphQL query against a schema. It helps in identifying errors and ensuring that the query adheres to the schema's rules.

const { validate } = require('graphql');
const { parse } = require('graphql-language-service-parser');
const { specifiedRules } = require('graphql-language-service');
const schema = /* GraphQLSchema object */;
const query = `query { user(id: 1) { name } }`;
const ast = parse(query);
const errors = validate(schema, ast, specifiedRules);
console.log(errors);

Autocomplete

This feature provides autocompletion suggestions for a given position in a GraphQL query. It is useful for building IDE extensions and other developer tools that enhance the GraphQL development experience.

const { getAutocompleteSuggestions } = require('graphql-language-service-interface');
const schema = /* GraphQLSchema object */;
const query = `query { user(`;
const position = { line: 0, character: 12 };
const suggestions = getAutocompleteSuggestions(schema, query, position);
console.log(suggestions);

Other packages similar to graphql-language-service

graphql

The 'graphql' package is the reference implementation of GraphQL for JavaScript. It provides a complete suite of tools for building GraphQL servers and clients, including parsing, validation, and execution. While it offers similar functionalities to 'graphql-language-service', it is more focused on server-side operations and less on language services for development tools.

codemirror-graphql

The 'codemirror-graphql' package provides a set of CodeMirror modes and utilities for working with GraphQL. It includes features like syntax highlighting, linting, and autocompletion. Compared to 'graphql-language-service', it is more focused on integrating GraphQL capabilities into the CodeMirror editor.

README

graphql-language-service

Note: This package will soon be renamed to graphql-language-service-cli

We welcome your feedback and suggestions.

GraphQL Language Service provides an interface for building GraphQL language services for IDEs.

Partial support for Microsoft's Language Server Protocol is in place, with more to come in the future.

Supported features include:

• Diagnostics (GraphQL syntax linting/validations) (spec-compliant)
• Autocomplete suggestions (spec-compliant)
• Hyperlink to fragment definitions and named types (type, input, enum) definitions (spec-compliant)
• Outline view support for queries

Installation and Usage

Dependencies

An LSP compatible client with it's own file watcher, that sends watch notifications to the server.

DROPPED: GraphQL Language Service no longer depends on Watchman

Installation

git clone [e-mail]:graphql/graphql-language-service.git
cd {path/to/your/repo}
npm install ../graphql-language-service

After pulling the latest changes from this repo, be sure to run yarn run build to transform the src/ directory and generate the dist/ directory.

The library includes a node executable file which you can find in ./node_modules/.bin/graphql.js after installation.

GraphQL configuration file (.graphqlrc.yml)

Check out graphql-config

The graphql features we support are:

• customDirectives - ['@myExampleDirective']
• customValidationRules - returns rules array with parameter ValidationContext from graphql/validation;

Using the command-line interface

The node executable contains several commands: server and a command-line language service methods (validate, autocomplete, outline).

Improving this list is a work-in-progress.

GraphQL Language Service Command-Line Interface.
Usage: bin/graphql.js <command> <file>
    [-h | --help]
    [-c | --configDir] {configDir}
    [-t | --text] {textBuffer}
    [-f | --file] {filePath}
    [-s | --schema] {schemaPath}


Options:
  -h, --help        Show help                                          [boolean]
  -t, --text        Text buffer to perform GraphQL diagnostics on.
                    Will defer to --file option if omitted.
                    Overrides the --file option, if any.
                                                                        [string]
  -f, --file        File path to perform GraphQL diagnostics on.
                    Will be ignored if --text option is supplied.
                                                                        [string]
  --row             A row number from the cursor location for GraphQL
                    autocomplete suggestions.
                    If omitted, the last row number will be used.
                                                                        [number]
  --column          A column number from the cursor location for GraphQL
                    autocomplete suggestions.
                    If omitted, the last column number will be used.
                                                                        [number]
  -c, --configDir   Path to the .graphqlrc.yml configuration file.
                    Walks up the directory tree from the provided config
                    directory, or the current working directory, until a
                    .graphqlrc is found or the root directory is found.
                                                                        [string]
  -s, --schemaPath  a path to schema DSL file
                                                                        [string]

At least one command is required.
Commands: "server, validate, autocomplete, outline"