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graphql-print

The printer that GraphQL always deserved.

✅ Pretty and minified printing

✅ Print comments

✅ Configure line length

✅ Choose custom indentation

Install

Note that graphql is a peer dependency of this package and needs to be installed as well.

npm i graphql graphql-print

Usage

This package supports printing any valid GraphQL AST node, as well as printing a list of nodes.

By default, the printer outputs a pretty-printed version of the given AST nodes, but it can be configured in different ways. The following table shows the supported options.

Option Type Default Description
minified boolean false Returns a minified version of the AST, optimizing for shortest string length
preserveComments boolean false All comments are stripped from the AST by default but can be perserved using this option
maxLineLength number 80 The printer tries to output lists of nodes in a single line where possible and only breaks lists items into individual lines when they become too long. This option controls the threshold for when a line should be broken up into multiple ones.
indentationStep string " " By default the printer uses two spaces for indentation, this option allows you to configure that. (Note that passing any characters other than ignored tokens will result in a string that does not represent the original AST anymore and might potentially be invalid.)

Example

import { parse } from "graphql";
import { print } from "graphql-print";

const ast = parse(`
  query MyQuery { 
    # select a field
    myField(myArg: 42, myOtherArg: null)
  }
`);

console.log(print(ast));
/**
 * Will print the following:
 *
 * query MyQuery {
 *   myField(myArg: 42, myOtherArg: null)
 * }
 */

console.log(print(ast, { minified: true }));
/**
 * Will print the following:
 *
 * query MyQuery{myField(myArg:42,myOtherArg:null)}
 */

console.log(print(ast, { preserveComments: true }));
/**
 * Will print the following:
 *
 * query MyQuery {
 *   # select a field
 *   myField(myArg: 42, myOtherArg: null)
 * }
 */

console.log(print(ast, { maxLineLength: 20 }));
/**
 * Will print the following:
 *
 * query MyQuery {
 *   myField(
 *     myArg: 42
 *     myOtherArg: null
 *   )
 * }
 */