nx/packages/next/plugins/with-nx.ts

import {
  createProjectGraphAsync,
  joinPathFragments,
  offsetFromRoot,
  parseTargetString,
  ProjectGraph,
  ProjectGraphProjectNode,
  Target,
  workspaceRoot,
} from '@nrwl/devkit';
import {
  calculateProjectDependencies,
  DependentBuildableProjectNode,
} from '@nrwl/js/src/utils/buildable-libs-utils';
import type { NextConfig } from 'next';
import { PHASE_PRODUCTION_SERVER } from 'next/constants';

import * as path from 'path';
import { createWebpackConfig } from '../src/utils/config';
import { NextBuildBuilderOptions } from '../src/utils/types';

export interface WithNxOptions extends NextConfig {
  nx?: {
    svgr?: boolean;
  };
}

export interface NextConfigFn {
  (phase: string): Promise<NextConfig>;
}

export interface WithNxContext {
  workspaceRoot: string;
  libsDir: string;
}

function regexEqual(x, y) {
  return (
    x instanceof RegExp &&
    y instanceof RegExp &&
    x.source === y.source &&
    x.global === y.global &&
    x.ignoreCase === y.ignoreCase &&
    x.multiline === y.multiline
  );
}

/**
 * Do not remove or rename this function. Production builds inline `with-nx.js` file with a replacement
 * To this function that hard-codes the libsDir.
 */
function getWithNxContext(): WithNxContext {
  const { workspaceRoot, workspaceLayout } = require('@nrwl/devkit');
  return {
    workspaceRoot,
    libsDir: workspaceLayout().libsDir,
  };
}

function getTargetConfig(graph: ProjectGraph, target: Target) {
  const projectNode = graph.nodes[target.project];
  return projectNode.data.targets[target.target];
}

function getOptions(graph: ProjectGraph, target: Target) {
  const targetConfig = getTargetConfig(graph, target);
  const options = targetConfig.options;
  if (target.configuration) {
    Object.assign(options, targetConfig.configurations[target.configuration]);
  }

  return options;
}

function getNxContext(
  graph: ProjectGraph,
  target: Target
): {
  node: ProjectGraphProjectNode;
  options: NextBuildBuilderOptions;
  projectName: string;
  targetName: string;
  configurationName?: string;
} {
  const targetConfig = getTargetConfig(graph, target);

  if ('@nrwl/next:build' === targetConfig.executor) {
    return {
      node: graph.nodes[target.project],
      options: getOptions(graph, target),
      projectName: target.project,
      targetName: target.target,
      configurationName: target.configuration,
    };
  }

  const targetOptions = getOptions(graph, target);

  // If we are running serve or export pull the options from the dependent target first (ex. build)
  if (targetOptions.devServerTarget) {
    const devServerTarget = parseTargetString(
      targetOptions.devServerTarget,
      graph
    );

    return getNxContext(graph, devServerTarget);
  } else if (
    ['@nrwl/next:server', '@nrwl/next:export'].includes(targetConfig.executor)
  ) {
    const buildTarget = parseTargetString(targetOptions.buildTarget, graph);
    return getNxContext(graph, buildTarget);
  } else {
    throw new Error(
      'Could not determine the config for this Next application.'
    );
  }
}

/**
 * Try to read output dir from project, and default to '.next' if executing outside of Nx (e.g. dist is added to a docker image).
 */
async function determineDistDirForProdServer(
  nextConfig: NextConfig
): Promise<string> {
  const project = process.env.NX_TASK_TARGET_PROJECT;
  const target = process.env.NX_TASK_TARGET_TARGET;
  const configuration = process.env.NX_TASK_TARGET_CONFIGURATION;

  if (project && target) {
    const originalTarget = { project, target, configuration };
    const graph = await createProjectGraphAsync();

    const { options, node: projectNode } = getNxContext(graph, originalTarget);
    const outputDir = `${offsetFromRoot(projectNode.data.root)}${
      options.outputPath
    }`;
    return nextConfig.distDir && nextConfig.distDir !== '.next'
      ? joinPathFragments(outputDir, nextConfig.distDir)
      : joinPathFragments(outputDir, '.next');
  } else {
    return '.next';
  }
}
export function withNx(
  _nextConfig = {} as WithNxOptions,
  context: WithNxContext = getWithNxContext()
): NextConfigFn {
  return async (phase: string) => {
    if (phase === PHASE_PRODUCTION_SERVER) {
      // If we are running an already built production server, just return the configuration.
      const { nx, ...validNextConfig } = _nextConfig;
      return {
        ...validNextConfig,
        distDir: await determineDistDirForProdServer(validNextConfig),
      };
    } else {
      // Otherwise, add in webpack and eslint configuration for build or test.
      let dependencies: DependentBuildableProjectNode[] = [];

      const graph = await createProjectGraphAsync();

      const originalTarget = {
        project: process.env.NX_TASK_TARGET_PROJECT,
        target: process.env.NX_TASK_TARGET_TARGET,
        configuration: process.env.NX_TASK_TARGET_CONFIGURATION,
      };

      const {
        node: projectNode,
        options,
        projectName: project,
        targetName,
        configurationName,
      } = getNxContext(graph, originalTarget);
      const projectDirectory = projectNode.data.root;

      if (options.buildLibsFromSource === false && targetName) {
        const result = calculateProjectDependencies(
          graph,
          workspaceRoot,
          project,
          targetName,
          configurationName
        );
        dependencies = result.dependencies;
      }

      // Get next config
      const nextConfig = getNextConfig(_nextConfig, context);

      const outputDir = `${offsetFromRoot(projectDirectory)}${
        options.outputPath
      }`;
      nextConfig.distDir =
        nextConfig.distDir && nextConfig.distDir !== '.next'
          ? joinPathFragments(outputDir, nextConfig.distDir)
          : joinPathFragments(outputDir, '.next');

      const userWebpackConfig = nextConfig.webpack;

      nextConfig.webpack = (a, b) =>
        createWebpackConfig(
          workspaceRoot,
          options.root,
          options.fileReplacements,
          options.assets,
          dependencies,
          path.join(workspaceRoot, context.libsDir)
        )(userWebpackConfig ? userWebpackConfig(a, b) : a, b);

      return nextConfig;
    }
  };
}

export function getNextConfig(
  nextConfig = {} as WithNxOptions,
  context: WithNxContext = getWithNxContext()
): NextConfig {
  // If `next-compose-plugins` is used, the context argument is invalid.
  if (!context.libsDir || !context.workspaceRoot) {
    context = getWithNxContext();
  }
  const userWebpack = nextConfig.webpack || ((x) => x);
  const { nx, ...validNextConfig } = nextConfig;
  return {
    eslint: {
      ignoreDuringBuilds: true,
      ...(validNextConfig.eslint ?? {}),
    },
    ...validNextConfig,
    webpack: (config, options) => {
      /*
       * Update babel to support our monorepo setup.
       * The 'upward' mode allows the root babel.config.json and per-project .babelrc files to be picked up.
       */
      options.defaultLoaders.babel.options.babelrc = true;
      options.defaultLoaders.babel.options.rootMode = 'upward';

      /*
       * Modify the Next.js webpack config to allow workspace libs to use css modules.
       * Note: This would be easier if Next.js exposes css-loader and sass-loader on `defaultLoaders`.
       */

      // Include workspace libs in css/sass loaders
      const includes = [
        require('path').join(context.workspaceRoot, context.libsDir),
      ];

      const nextCssLoaders = config.module.rules.find(
        (rule) => typeof rule.oneOf === 'object'
      );

      // webpack config is not as expected
      if (!nextCssLoaders) return config;

      /*
       *  1. Modify css loader to enable module support for workspace libs
       */
      const nextCssLoader = nextCssLoaders.oneOf.find(
        (rule) =>
          rule.sideEffects === false && regexEqual(rule.test, /\.module\.css$/)
      );
      // Might not be found if Next.js webpack config changes in the future
      if (nextCssLoader && nextCssLoader.issuer) {
        nextCssLoader.issuer.or = nextCssLoader.issuer.and
          ? nextCssLoader.issuer.and.concat(includes)
          : includes;
        delete nextCssLoader.issuer.and;
      }

      /*
       *  2. Modify sass loader to enable module support for workspace libs
       */
      const nextSassLoader = nextCssLoaders.oneOf.find(
        (rule) =>
          rule.sideEffects === false &&
          regexEqual(rule.test, /\.module\.(scss|sass)$/)
      );
      // Might not be found if Next.js webpack config changes in the future
      if (nextSassLoader && nextSassLoader.issuer) {
        nextSassLoader.issuer.or = nextSassLoader.issuer.and
          ? nextSassLoader.issuer.and.concat(includes)
          : includes;
        delete nextSassLoader.issuer.and;
      }

      /*
       *  3. Modify error loader to ignore css modules used by workspace libs
       */
      const nextErrorCssModuleLoader = nextCssLoaders.oneOf.find(
        (rule) =>
          rule.use &&
          rule.use.loader === 'error-loader' &&
          rule.use.options &&
          (rule.use.options.reason ===
            'CSS Modules \u001b[1mcannot\u001b[22m be imported from within \u001b[1mnode_modules\u001b[22m.\n' +
              'Read more: https://err.sh/next.js/css-modules-npm' ||
            rule.use.options.reason ===
              'CSS Modules cannot be imported from within node_modules.\nRead more: https://err.sh/next.js/css-modules-npm')
      );
      // Might not be found if Next.js webpack config changes in the future
      if (nextErrorCssModuleLoader) {
        nextErrorCssModuleLoader.exclude = includes;
      }

      /**
       * 4. Modify css loader to allow global css from node_modules to be imported from workspace libs
       */
      const nextGlobalCssLoader = nextCssLoaders.oneOf.find((rule) =>
        rule.include?.and?.find((include) =>
          regexEqual(include, /node_modules/)
        )
      );
      // Might not be found if Next.js webpack config changes in the future
      if (nextGlobalCssLoader && nextGlobalCssLoader.issuer) {
        nextGlobalCssLoader.issuer.or = nextGlobalCssLoader.issuer.and
          ? nextGlobalCssLoader.issuer.and.concat(includes)
          : includes;
        delete nextGlobalCssLoader.issuer.and;
      }

      /**
       * 5. Add env variables prefixed with NX_
       */
      addNxEnvVariables(config);

      /**
       * 6. Add SVGR support if option is on.
       */

      // Default SVGR support to be on for projects.
      if (nx?.svgr !== false) {
        config.module.rules.push({
          test: /\.svg$/,
          oneOf: [
            // If coming from JS/TS file, then transform into React component using SVGR.
            {
              issuer: /\.[jt]sx?$/,
              use: [
                {
                  loader: require.resolve('@svgr/webpack'),
                  options: {
                    svgo: false,
                    titleProp: true,
                    ref: true,
                  },
                },
                {
                  loader: require.resolve('url-loader'),
                  options: {
                    limit: 10000, // 10kB
                    name: '[name].[hash:7].[ext]',
                  },
                },
              ],
            },
            // Fallback to plain URL loader if someone just imports the SVG and references it on the <img src> tag
            {
              loader: require.resolve('url-loader'),
              options: {
                limit: 10000, // 10kB
                name: '[name].[hash:7].[ext]',
              },
            },
          ],
        });
      }

      return userWebpack(config, options);
    },
  };
}

function getNxEnvironmentVariables() {
  return Object.keys(process.env)
    .filter((env) => /^NX_/i.test(env))
    .reduce((env, key) => {
      env[key] = process.env[key];
      return env;
    }, {});
}

function addNxEnvVariables(config: any) {
  const maybeDefinePlugin = config.plugins?.find((plugin) => {
    return plugin.definitions?.['process.env.NODE_ENV'];
  });

  if (maybeDefinePlugin) {
    const env = getNxEnvironmentVariables();

    Object.entries(env)
      .map(([name, value]) => [`process.env.${name}`, `"${value}"`])
      .filter(([name]) => !maybeDefinePlugin.definitions[name])
      .forEach(
        ([name, value]) => (maybeDefinePlugin.definitions[name] = value)
      );
  }
}

// Support for older generated code: `const withNx = require('@nrwl/next/plugins/with-nx');`
module.exports = withNx;
// Support for newer generated code: `const { withNx } = require(...);`
module.exports.withNx = withNx;
module.exports.getNextConfig = getNextConfig;