add missing src/content-entry-filesystem.mjs from template

src/content-entry-filesystem.mjs

@@ -0,0 +1,195 @@
+import { join } from "node:path";
+import { createReadStream, createWriteStream, constants } from "node:fs";
+import { ReadableStream } from "node:stream/web";
+import { Readable, Writable } from "node:stream";
+import { access, stat } from "node:fs/promises";
+import { ContentEntry, StreamContentEntryMixin } from "content-entry";
+
+/**
+ * A ContentEntry backed by a file.
+ */
+export class FileSystemEntry extends StreamContentEntryMixin(ContentEntry) {
+  /** @type {string} */ baseDir;
+
+  /**
+   * @param {string} name of the file
+   * @param {string} baseDir directory the file is located in
+   * @property {string} name of the file
+   * @property {string} baseDir directory the file is located in
+   */
+  constructor(name, baseDir) {
+    // @ts-ignore
+    super(name);
+    this.baseDir = baseDir;
+  }
+
+  /**
+   * Absolute file path.
+   * @return {string}
+   */
+  get filename() {
+    return join(this.baseDir, this.name);
+  }
+
+  /**
+   * Check for presence of the entry.
+   * @return {Promise<boolean>}
+   */
+  get isExistent() {
+    return exits(this.filename);
+  }
+
+  /**
+   * Check is entry represents an empty file.
+   * @return {Promise<boolean>}
+   */
+  get isEmpty() {
+    return empty(this.filename);
+  }
+
+  #stat;
+
+  /**
+   * @return {Promise<number>}
+   */
+  get size() {
+    if (this.#stat) {
+      return this.#stat.size;
+    }
+
+    return stat(this.filename).then(stat => {
+      this.#stat = stat;
+      return stat.size;
+    });
+  }
+
+  /**
+   * @return {Promise<Date>}
+   */
+  get atime() {
+    if (this.#stat) {
+      return this.#stat.ctime;
+    }
+
+    return stat(this.filename).then(stat => {
+      this.#stat = stat;
+      return stat.atime;
+    });
+  }
+
+  /**
+   * @return {Promise<Date>}
+   */
+  get ctime() {
+    if (this.#stat) {
+      return this.#stat.ctime;
+    }
+
+    return stat(this.filename).then(stat => {
+      this.#stat = stat;
+      return stat.ctime;
+    });
+  }
+
+  /**
+   * @return {Promise<Date>}
+   */
+  get mtime() {
+    if (this.#stat) {
+      return this.#stat.mtime;
+    }
+
+    return stat(this.filename).then(stat => {
+      this.#stat = stat;
+      return stat.mtime;
+    });
+  }
+
+  /**
+   * @return {Promise<number>}
+   */
+  get uid() {
+    if (this.#stat) {
+      return this.#stat.uid;
+    }
+
+    return stat(this.filename).then(stat => {
+      this.#stat = stat;
+      return stat.uid;
+    });
+  }
+
+  /**
+   * @return {Promise<number>}
+   */
+  get gid() {
+    if (this.#stat) {
+      return this.#stat.gid;
+    }
+
+    return stat(this.filename).then(stat => {
+      this.#stat = stat;
+      return stat.gid;
+    });
+  }
+
+  /**
+   * @return {ReadableStream}
+   */
+  get readStream() {
+    return Readable.toWeb(createReadStream(this.filename));
+  }
+
+  /**
+   * @return {WritableStream}
+   */
+  get writeStream() {
+    return Writable.toWeb(createWriteStream(this.filename));
+  }
+
+  /**
+   *
+   * @returns {Object}
+   */
+  toJSON() {
+    const json = super.toJSON();
+    json.baseDir = this.baseDir;
+    return json;
+  }
+
+  /**
+   * @deprecated
+   */
+  getReadStream(options) {
+    return Readable.toWeb(createReadStream(this.filename, options));
+  }
+
+  /**
+   * @deprecated
+   */
+  getWriteStream(options) {
+    return createWriteStream(this.filename, options);
+  }
+}
+
+async function exits(file) {
+  try {
+    await access(file, constants.F_OK);
+  } catch {
+    return false;
+  }
+
+  return true;
+}
+
+async function empty(file) {
+  try {
+    const s = await stat(file);
+    return s.size === 0;
+  } catch (e) {
+    if (e.code === "ENOENT") {
+      return true;
+    }
+    throw e;
+  }
+}