index.js

import path from "path";
import crypto from "crypto";

import { validate } from "schema-utils";
import pLimit from "p-limit";
import globby from "globby";
import serialize from "serialize-javascript";
import normalizePath from "normalize-path";
import globParent from "glob-parent";
import fastGlob from "fast-glob";

import { version } from "../package.json";

import schema from "./options.json";
import { readFile, stat } from "./utils/promisify";

const template = /\[\\*([\w:]+)\\*\]/i;

class CopyPlugin {
  constructor(options = {}) {
    validate(schema, options, {
      name: "Copy Plugin",
      baseDataPath: "options",
    });

    this.patterns = options.patterns;
    this.options = options.options || {};
  }

  static async createSnapshot(compilation, startTime, dependency) {
    // eslint-disable-next-line consistent-return
    return new Promise((resolve, reject) => {
      compilation.fileSystemInfo.createSnapshot(
        startTime,
        [dependency],
        // eslint-disable-next-line no-undefined
        undefined,
        // eslint-disable-next-line no-undefined
        undefined,
        null,
        (error, snapshot) => {
          if (error) {
            reject(error);

            return;
          }

          resolve(snapshot);
        }
      );
    });
  }

  static async checkSnapshotValid(compilation, snapshot) {
    // eslint-disable-next-line consistent-return
    return new Promise((resolve, reject) => {
      compilation.fileSystemInfo.checkSnapshotValid(
        snapshot,
        (error, isValid) => {
          if (error) {
            reject(error);

            return;
          }

          resolve(isValid);
        }
      );
    });
  }

  static getContentHash(compiler, compilation, source) {
    const { outputOptions } = compilation;
    const {
      hashDigest,
      hashDigestLength,
      hashFunction,
      hashSalt,
    } = outputOptions;
    const hash = compiler.webpack.util.createHash(hashFunction);

    if (hashSalt) {
      hash.update(hashSalt);
    }

    hash.update(source);

    const fullContentHash = hash.digest(hashDigest);

    return fullContentHash.slice(0, hashDigestLength);
  }

  static async runPattern(
    compiler,
    compilation,
    logger,
    cache,
    inputPattern,
    index
  ) {
    const { RawSource } = compiler.webpack.sources;
    const pattern =
      typeof inputPattern === "string"
        ? { from: inputPattern }
        : { ...inputPattern };

    pattern.fromOrigin = pattern.from;
    pattern.from = path.normalize(pattern.from);
    pattern.context =
      typeof pattern.context === "undefined"
        ? compiler.context
        : path.isAbsolute(pattern.context)
        ? pattern.context
        : path.join(compiler.context, pattern.context);

    logger.log(
      `starting to process a pattern from '${pattern.from}' using '${pattern.context}' context`
    );

    if (path.isAbsolute(pattern.from)) {
      pattern.absoluteFrom = pattern.from;
    } else {
      pattern.absoluteFrom = path.resolve(pattern.context, pattern.from);
    }

    logger.debug(`getting stats for '${pattern.absoluteFrom}'...`);

    const { inputFileSystem } = compiler;

    let stats;

    try {
      stats = await stat(inputFileSystem, pattern.absoluteFrom);
    } catch (error) {
      // Nothing
    }

    if (stats) {
      if (stats.isDirectory()) {
        pattern.fromType = "dir";
        logger.debug(`determined '${pattern.absoluteFrom}' is a directory`);
      } else if (stats.isFile()) {
        pattern.fromType = "file";
        logger.debug(`determined '${pattern.absoluteFrom}' is a file`);
      } else {
        logger.debug(`determined '${pattern.absoluteFrom}' is a glob`);
      }
    }

    // eslint-disable-next-line no-param-reassign
    pattern.globOptions = {
      ...{ followSymbolicLinks: true },
      ...(pattern.globOptions || {}),
      ...{ cwd: pattern.context, objectMode: true },
    };

    pattern.globOptions.fs = inputFileSystem;

    switch (pattern.fromType) {
      case "dir":
        compilation.contextDependencies.add(pattern.absoluteFrom);

        logger.debug(`added '${pattern.absoluteFrom}' as a context dependency`);

        /* eslint-disable no-param-reassign */
        pattern.context = pattern.absoluteFrom;
        pattern.glob = path.posix.join(
          fastGlob.escapePath(
            normalizePath(path.resolve(pattern.absoluteFrom))
          ),
          "**/*"
        );
        pattern.absoluteFrom = path.join(pattern.absoluteFrom, "**/*");

        if (typeof pattern.globOptions.dot === "undefined") {
          pattern.globOptions.dot = true;
        }
        /* eslint-enable no-param-reassign */
        break;
      case "file":
        compilation.fileDependencies.add(pattern.absoluteFrom);

        logger.debug(`added '${pattern.absoluteFrom}' as a file dependency`);

        /* eslint-disable no-param-reassign */
        pattern.context = path.dirname(pattern.absoluteFrom);
        pattern.glob = fastGlob.escapePath(
          normalizePath(path.resolve(pattern.absoluteFrom))
        );

        if (typeof pattern.globOptions.dot === "undefined") {
          pattern.globOptions.dot = true;
        }
        /* eslint-enable no-param-reassign */
        break;
      default: {
        const contextDependencies = path.normalize(
          globParent(pattern.absoluteFrom)
        );

        compilation.contextDependencies.add(contextDependencies);

        logger.debug(`added '${contextDependencies}' as a context dependency`);

        /* eslint-disable no-param-reassign */
        pattern.fromType = "glob";
        pattern.glob = path.isAbsolute(pattern.fromOrigin)
          ? pattern.fromOrigin
          : path.posix.join(
              fastGlob.escapePath(normalizePath(path.resolve(pattern.context))),
              pattern.fromOrigin
            );
        /* eslint-enable no-param-reassign */
      }
    }

    logger.log(`begin globbing '${pattern.glob}'...`);

    let paths;

    try {
      paths = await globby(pattern.glob, pattern.globOptions);
    } catch (error) {
      compilation.errors.push(error);

      return;
    }

    if (paths.length === 0) {
      if (pattern.noErrorOnMissing) {
        logger.log(
          `finished to process a pattern from '${pattern.from}' using '${pattern.context}' context to '${pattern.to}'`
        );

        return;
      }

      const missingError = new Error(`unable to locate '${pattern.glob}' glob`);

      compilation.errors.push(missingError);

      return;
    }

    const filteredPaths = (
      await Promise.all(
        paths.map(async (item) => {
          // Exclude directories
          if (!item.dirent.isFile()) {
            return false;
          }

          if (pattern.filter) {
            let isFiltered;

            try {
              isFiltered = await pattern.filter(item.path);
            } catch (error) {
              compilation.errors.push(error);

              return false;
            }

            if (!isFiltered) {
              logger.log(`skip '${item.path}', because it was filtered`);
            }

            return isFiltered ? item : false;
          }

          return item;
        })
      )
    ).filter((item) => item);

    if (filteredPaths.length === 0) {
      if (pattern.noErrorOnMissing) {
        logger.log(
          `finished to process a pattern from '${pattern.from}' using '${pattern.context}' context to '${pattern.to}'`
        );

        return;
      }

      const missingError = new Error(
        `unable to locate '${pattern.glob}' glob after filtering paths`
      );

      compilation.errors.push(missingError);

      return;
    }

    const files = await Promise.all(
      filteredPaths.map(async (item) => {
        const from = item.path;

        logger.debug(`found '${from}'`);

        // `globby`/`fast-glob` return the relative path when the path contains special characters on windows
        const absoluteFilename = path.resolve(pattern.context, from);

        pattern.to =
          typeof pattern.to === "function"
            ? await pattern.to({ context: pattern.context, absoluteFilename })
            : path.normalize(
                typeof pattern.to !== "undefined" ? pattern.to : ""
              );

        const isToDirectory =
          path.extname(pattern.to) === "" || pattern.to.slice(-1) === path.sep;

        const toType = pattern.toType
          ? pattern.toType
          : template.test(pattern.to)
          ? "template"
          : isToDirectory
          ? "dir"
          : "file";

        logger.log(`'to' option '${pattern.to}' determinated as '${toType}'`);

        const relativeFrom = path.relative(pattern.context, absoluteFilename);
        let filename =
          toType === "dir" ? path.join(pattern.to, relativeFrom) : pattern.to;

        if (path.isAbsolute(filename)) {
          filename = path.relative(compiler.options.output.path, filename);
        }

        logger.log(`determined that '${from}' should write to '${filename}'`);

        const sourceFilename = normalizePath(
          path.relative(compiler.context, absoluteFilename)
        );

        return {
          absoluteFilename,
          sourceFilename,
          filename,
          toType,
        };
      })
    );

    let assets;

    try {
      assets = await Promise.all(
        files.map(async (file) => {
          const { absoluteFilename, sourceFilename, filename, toType } = file;
          const info =
            typeof pattern.info === "function"
              ? pattern.info(file) || {}
              : pattern.info || {};
          const result = {
            absoluteFilename,
            sourceFilename,
            filename,
            force: pattern.force,
            info,
          };

          // If this came from a glob or dir, add it to the file dependencies
          if (pattern.fromType === "dir" || pattern.fromType === "glob") {
            compilation.fileDependencies.add(absoluteFilename);

            logger.debug(`added '${absoluteFilename}' as a file dependency`);
          }

          let cacheEntry;

          logger.debug(`getting cache for '${absoluteFilename}'...`);

          try {
            cacheEntry = await cache.getPromise(
              `${sourceFilename}|${index}`,
              null
            );
          } catch (error) {
            compilation.errors.push(error);

            return;
          }

          if (cacheEntry) {
            logger.debug(`found cache for '${absoluteFilename}'...`);

            let isValidSnapshot;

            logger.debug(
              `checking snapshot on valid for '${absoluteFilename}'...`
            );

            try {
              isValidSnapshot = await CopyPlugin.checkSnapshotValid(
                compilation,
                cacheEntry.snapshot
              );
            } catch (error) {
              compilation.errors.push(error);

              return;
            }

            if (isValidSnapshot) {
              logger.debug(`snapshot for '${absoluteFilename}' is valid`);

              result.source = cacheEntry.source;
            } else {
              logger.debug(`snapshot for '${absoluteFilename}' is invalid`);
            }
          } else {
            logger.debug(`missed cache for '${absoluteFilename}'`);
          }

          if (!result.source) {
            const startTime = Date.now();

            logger.debug(`reading '${absoluteFilename}'...`);

            let data;

            try {
              data = await readFile(inputFileSystem, absoluteFilename);
            } catch (error) {
              compilation.errors.push(error);

              return;
            }

            logger.debug(`read '${absoluteFilename}'`);

            result.source = new RawSource(data);

            let snapshot;

            logger.debug(`creating snapshot for '${absoluteFilename}'...`);

            try {
              snapshot = await CopyPlugin.createSnapshot(
                compilation,
                startTime,
                absoluteFilename
              );
            } catch (error) {
              compilation.errors.push(error);

              return;
            }

            if (snapshot) {
              logger.debug(`created snapshot for '${absoluteFilename}'`);
              logger.debug(`storing cache for '${absoluteFilename}'...`);

              try {
                await cache.storePromise(`${sourceFilename}|${index}`, null, {
                  source: result.source,
                  snapshot,
                });
              } catch (error) {
                compilation.errors.push(error);

                return;
              }

              logger.debug(`stored cache for '${absoluteFilename}'`);
            }
          }

          if (pattern.transform) {
            const transform =
              typeof pattern.transform === "function"
                ? { transformer: pattern.transform }
                : pattern.transform;

            if (transform.transformer) {
              logger.log(`transforming content for '${absoluteFilename}'...`);

              const buffer = result.source.buffer();

              if (transform.cache) {
                const defaultCacheKeys = {
                  version,
                  sourceFilename,
                  transform: transform.transformer,
                  contentHash: crypto
                    .createHash("md4")
                    .update(buffer)
                    .digest("hex"),
                  index,
                };
                const cacheKeys = `transform|${serialize(
                  typeof transform.cache.keys === "function"
                    ? await transform.cache.keys(
                        defaultCacheKeys,
                        absoluteFilename
                      )
                    : { ...defaultCacheKeys, ...pattern.transform.cache.keys }
                )}`;

                logger.debug(
                  `getting transformation cache for '${absoluteFilename}'...`
                );

                const cacheItem = cache.getItemCache(
                  cacheKeys,
                  cache.getLazyHashedEtag(result.source)
                );

                result.source = await cacheItem.getPromise();

                logger.debug(
                  result.source
                    ? `found transformation cache for '${absoluteFilename}'`
                    : `no transformation cache for '${absoluteFilename}'`
                );

                if (!result.source) {
                  const transformed = await transform.transformer(
                    buffer,
                    absoluteFilename
                  );

                  result.source = new RawSource(transformed);

                  logger.debug(
                    `caching transformation for '${absoluteFilename}'...`
                  );

                  await cacheItem.storePromise(result.source);

                  logger.debug(
                    `cached transformation for '${absoluteFilename}'`
                  );
                }
              } else {
                result.source = new RawSource(
                  await transform.transformer(buffer, absoluteFilename)
                );
              }
            }
          }

          if (toType === "template") {
            logger.log(
              `interpolating template '${filename}' for '${sourceFilename}'...`
            );

            const contentHash = CopyPlugin.getContentHash(
              compiler,
              compilation,
              result.source.buffer()
            );
            const ext = path.extname(result.sourceFilename);
            const base = path.basename(result.sourceFilename);
            const name = base.slice(0, base.length - ext.length);
            const data = {
              filename: normalizePath(
                path.relative(pattern.context, absoluteFilename)
              ),
              contentHash,
              chunk: {
                name,
                id: result.sourceFilename,
                hash: contentHash,
                contentHash,
              },
            };
            const {
              path: interpolatedFilename,
              info: assetInfo,
            } = compilation.getPathWithInfo(
              normalizePath(result.filename),
              data
            );

            result.info = { ...result.info, ...assetInfo };
            result.filename = interpolatedFilename;

            logger.log(
              `interpolated template '${filename}' for '${sourceFilename}'`
            );
          } else {
            // eslint-disable-next-line no-param-reassign
            result.filename = normalizePath(result.filename);
          }

          // eslint-disable-next-line consistent-return
          return result;
        })
      );
    } catch (error) {
      compilation.errors.push(error);

      return;
    }

    logger.log(
      `finished to process a pattern from '${pattern.from}' using '${pattern.context}' context to '${pattern.to}'`
    );

    // eslint-disable-next-line consistent-return
    return assets;
  }

  apply(compiler) {
    const pluginName = this.constructor.name;
    const limit = pLimit(this.options.concurrency || 100);

    compiler.hooks.thisCompilation.tap(pluginName, (compilation) => {
      const logger = compilation.getLogger("copy-webpack-plugin");
      const cache = compilation.getCache("CopyWebpackPlugin");

      compilation.hooks.processAssets.tapAsync(
        {
          name: "copy-webpack-plugin",
          stage: compiler.webpack.Compilation.PROCESS_ASSETS_STAGE_ADDITIONAL,
        },
        async (unusedAssets, callback) => {
          logger.log("starting to add additional assets...");

          const assetMap = new Map();

          await Promise.all(
            this.patterns.map((item, index) =>
              limit(async () => {
                let assets;

                try {
                  assets = await CopyPlugin.runPattern(
                    compiler,
                    compilation,
                    logger,
                    cache,
                    item,
                    index
                  );
                } catch (error) {
                  compilation.errors.push(error);

                  return;
                }

                if (assets && assets.length > 0) {
                  if (item.transformAll) {
                    if (typeof item.to === "undefined") {
                      compilation.errors.push(
                        new Error(
                          `Invalid "pattern.to" for the "pattern.from": "${item.from}" and "pattern.transformAll" function. The "to" option must be specified.`
                        )
                      );

                      return;
                    }

                    assets.sort((a, b) =>
                      a.absoluteFilename > b.absoluteFilename
                        ? 1
                        : a.absoluteFilename < b.absoluteFilename
                        ? -1
                        : 0
                    );

                    const mergedEtag =
                      assets.length === 1
                        ? cache.getLazyHashedEtag(assets[0].source.buffer())
                        : assets.reduce((accumulator, asset, i) => {
                            // eslint-disable-next-line no-param-reassign
                            accumulator = cache.mergeEtags(
                              i === 1
                                ? cache.getLazyHashedEtag(
                                    accumulator.source.buffer()
                                  )
                                : accumulator,
                              cache.getLazyHashedEtag(asset.source.buffer())
                            );

                            return accumulator;
                          });

                    const cacheKeys = `transformAll|${serialize({
                      version,
                      from: item.from,
                      to: item.to,
                      transformAll: item.transformAll,
                    })}`;
                    const eTag = cache.getLazyHashedEtag(mergedEtag);
                    const cacheItem = cache.getItemCache(cacheKeys, eTag);
                    let transformedAsset = await cacheItem.getPromise();

                    if (!transformedAsset) {
                      transformedAsset = { filename: item.to };

                      try {
                        transformedAsset.data = await item.transformAll(
                          assets.map((asset) => {
                            return {
                              data: asset.source.buffer(),
                              sourceFilename: asset.sourceFilename,
                              absoluteFilename: asset.absoluteFilename,
                            };
                          })
                        );
                      } catch (error) {
                        compilation.errors.push(error);

                        return;
                      }

                      if (template.test(item.to)) {
                        const contentHash = CopyPlugin.getContentHash(
                          compiler,
                          compilation,
                          transformedAsset.data
                        );

                        const {
                          path: interpolatedFilename,
                          info: assetInfo,
                        } = compilation.getPathWithInfo(
                          normalizePath(item.to),
                          {
                            contentHash,
                            chunk: {
                              hash: contentHash,
                              contentHash,
                            },
                          }
                        );

                        transformedAsset.filename = interpolatedFilename;
                        transformedAsset.info = assetInfo;
                      }

                      const { RawSource } = compiler.webpack.sources;

                      transformedAsset.source = new RawSource(
                        transformedAsset.data
                      );
                      transformedAsset.force = item.force;

                      await cacheItem.storePromise(transformedAsset);
                    }

                    assets = [transformedAsset];
                  }

                  const priority = item.priority || 0;

                  if (!assetMap.has(priority)) {
                    assetMap.set(priority, []);
                  }

                  assetMap.get(priority).push(...assets);
                }
              })
            )
          );

          const assets = [...assetMap.entries()].sort((a, b) => a[0] - b[0]);

          // Avoid writing assets inside `p-limit`, because it creates concurrency.
          // It could potentially lead to an error - 'Multiple assets emit different content to the same filename'
          assets
            .reduce((acc, val) => acc.concat(val[1]), [])
            .filter(Boolean)
            .forEach((asset) => {
              const {
                absoluteFilename,
                sourceFilename,
                filename,
                source,
                force,
              } = asset;

              const existingAsset = compilation.getAsset(filename);

              if (existingAsset) {
                if (force) {
                  const info = { copied: true, sourceFilename };

                  logger.log(
                    `force updating '${filename}' from '${absoluteFilename}' to compilation assets, because it already exists...`
                  );

                  compilation.updateAsset(filename, source, {
                    ...info,
                    ...asset.info,
                  });

                  logger.log(
                    `force updated '${filename}' from '${absoluteFilename}' to compilation assets, because it already exists`
                  );

                  return;
                }

                logger.log(
                  `skip adding '${filename}' from '${absoluteFilename}' to compilation assets, because it already exists`
                );

                return;
              }

              const info = { copied: true, sourceFilename };

              logger.log(
                `writing '${filename}' from '${absoluteFilename}' to compilation assets...`
              );

              compilation.emitAsset(filename, source, {
                ...info,
                ...asset.info,
              });

              logger.log(
                `written '${filename}' from '${absoluteFilename}' to compilation assets`
              );
            });

          logger.log("finished to adding additional assets");

          callback();
        }
      );

      if (compilation.hooks.statsPrinter) {
        compilation.hooks.statsPrinter.tap(pluginName, (stats) => {
          stats.hooks.print
            .for("asset.info.copied")
            .tap("copy-webpack-plugin", (copied, { green, formatFlag }) =>
              // eslint-disable-next-line no-undefined
              copied ? green(formatFlag("copied")) : undefined
            );
        });
      }
    });
  }
}

export default CopyPlugin;