Babel-plugin-transform-relay-hot NPM

babel-plugin-transform-relay-hot

Babel 6 plugin for transforming graphql literals and Relay.QL tagged templates (when "compat": true). It uses json/graphql file with GraphQL schema. This plugin wraps babel-plugin-relay. Each time the schema file changes, the wrapper updates instance of babel-plugin-relay with new schema without completely restarting dev server.

Install

yarn add babel-plugin-transform-relay-hot --dev

npm install babel-plugin-transform-relay-hot --save-dev

Usage with .babelrc

{
  "plugins": [
    ["transform-relay-hot", {
      "schema": "./build/schema.graphql",
      "watchInterval": 2000,
      "verbose": true
    }],
  ]
}

Options

schema
- Required
- Type: String
- Path to graphql schema json/graphql file
watchInterval
- Type: Number
- Default: 2000
- Time interval in milliseconds to check mtime of json file. Internally used setTimeout().unref() cause fs.watch blocks babel from exit.
- You may disable watching by setting watchInterval: 0.
verbose
- Type: Boolean
- Default: false
- Log to console when schema reloaded.
Also you may define additional options from babel-plugin-relay

Use "compat": true option for Relay Classic.

How to generate `schema.graphql` or `schema.graphql.json` files

You may use webpack-plugin-graphql-schema-hot or do it manually:

import fs from 'fs';
import path from 'path';
import { printSchema } from 'graphql';
import Schema from './schema';

export default function generateSchema() {
  fs.writeFileSync(
    path.join(__dirname, './build/schema.graphql'),
    printSchema(schema)
  );
}

import fs from 'fs';
import path from 'path';
import { graphql, introspectionQuery } from 'graphql';
import Schema from './schema';

export default async function generateSchemaJson() {
  const result = await (graphql(Schema, introspectionQuery));
  fs.writeFileSync(
    path.join(__dirname, './build/schema.graphql.json'),
    JSON.stringify(result, null, 2)
  );
}

Recommended modules

🔥 webpack-plugin-graphql-schema-hot

Webpack plugin which tracks changes in your GraphQL Schema files and generates schema introspection in json and txt formats. webpack-plugin-graphql-schema-hot can freeze Webpack, while this plugin catch changes from json file. For this you need set waitOnStart and waitOnRebuild options (in Webpack plugin) equal to watchInterval (from this babel plugin):

import path from 'path';
import WebpackPluginGraphqlSchemaHot from 'webpack-plugin-graphql-schema-hot';

const config = {
  // ...
  plugins: [
    new WebpackPluginGraphqlSchemaHot({
      schemaPath: path.resolve(__dirname, '../schema/index.js'),
      output: {
        json: path.resolve(__dirname, '../build/schema.graphql.json'),
        txt: path.resolve(__dirname, '../build/schema.graphql'),
      },
      runOnStart: true,
      waitOnStart: 2000, // <----- value from `watchInterval`
      waitOnRebuild: 2000, // <----- value from `watchInterval`
      verbose: true,
    }),
  ]
}

🔥 eslint-plugin-graphql

For eslint checks of Relay.QL tagged templates you may use eslint-plugin-graphql. It also tracks changes of graphql schema json file with following config:

// In a file called .eslintrc.js
const path = require('path');

module.exports = {
  parser: "babel-eslint",
  rules: {
    "graphql/template-strings": ['error', {
      env: 'relay',
      schemaJsonFilepath: path.resolve(__dirname, './build/schema.graphql.json'),
    }]
  },
  plugins: [
    'graphql'
  ]
}