+ const boundFn = fn.bind(this)
+ if (firstEntry) {
+ this.taskFunctions.set(DEFAULT_TASK_NAME, boundFn)
+ firstEntry = false
+ }
+ this.taskFunctions.set(name, boundFn)
+ }
+ if (firstEntry) {
+ throw new Error('taskFunctions parameter object is empty')
+ }
+ } else {
+ throw new TypeError(
+ 'taskFunctions parameter is not a function or a plain object'
+ )
+ }
+ }
+
+ /**
+ * Checks if the worker has a task function with the given name.
+ *
+ * @param name - The name of the task function to check.
+ * @returns Whether the worker has a task function with the given name or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ */
+ public hasTaskFunction (name: string): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ return this.taskFunctions.has(name)
+ }
+
+ /**
+ * Adds a task function to the worker.
+ * If a task function with the same name already exists, it is replaced.
+ *
+ * @param name - The name of the task function to add.
+ * @param fn - The task function to add.
+ * @returns Whether the task function was added or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the default task function reserved name.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `fn` parameter is not a function.
+ */
+ public addTaskFunction (
+ name: string,
+ fn: TaskFunction<Data, Response>
+ ): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ throw new Error(
+ 'Cannot add a task function with the default reserved name'
+ )
+ }
+ if (typeof fn !== 'function') {
+ throw new TypeError('fn parameter is not a function')
+ }
+ try {
+ const boundFn = fn.bind(this)
+ if (
+ this.taskFunctions.get(name) ===
+ this.taskFunctions.get(DEFAULT_TASK_NAME)
+ ) {
+ this.taskFunctions.set(DEFAULT_TASK_NAME, boundFn)
+ }
+ this.taskFunctions.set(name, boundFn)
+ return true
+ } catch {
+ return false
+ }
+ }
+
+ /**
+ * Removes a task function from the worker.
+ *
+ * @param name - The name of the task function to remove.
+ * @returns Whether the task function existed and was removed or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the default task function reserved name.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the task function used as default task function.
+ */
+ public removeTaskFunction (name: string): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ throw new Error(
+ 'Cannot remove the task function with the default reserved name'
+ )
+ }
+ if (
+ this.taskFunctions.get(name) === this.taskFunctions.get(DEFAULT_TASK_NAME)
+ ) {
+ throw new Error(
+ 'Cannot remove the task function used as the default task function'
+ )
+ }
+ return this.taskFunctions.delete(name)
+ }
+
+ /**
+ * Lists the names of the worker's task functions.
+ *
+ * @returns The names of the worker's task functions.
+ */
+ public listTaskFunctions (): string[] {
+ return [...this.taskFunctions.keys()]
+ }
+
+ /**
+ * Sets the default task function to use in the worker.
+ *
+ * @param name - The name of the task function to use as default task function.
+ * @returns Whether the default task function was set or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the default task function reserved name.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is a non-existing task function.
+ */
+ public setDefaultTaskFunction (name: string): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ throw new Error(
+ 'Cannot set the default task function reserved name as the default task function'
+ )
+ }
+ if (!this.taskFunctions.has(name)) {
+ throw new Error(
+ 'Cannot set the default task function to a non-existing task function'
+ )
+ }
+ try {
+ this.taskFunctions.set(
+ DEFAULT_TASK_NAME,
+ this.taskFunctions.get(name) as TaskFunction<Data, Response>
+ )
+ return true
+ } catch {
+ return false
+ }
+ }
+
+ /**
+ * Handles the ready message sent by the main worker.
+ *
+ * @param message - The ready message.
+ */
+ protected abstract handleReadyMessage (message: MessageValue<Data>): void
+
+ /**
+ * Worker message listener.
+ *
+ * @param message - The received message.
+ */
+ protected messageListener (message: MessageValue<Data>): void {
+ if (message.workerId === this.id) {
+ if (message.statistics != null) {
+ // Statistics message received
+ this.statistics = message.statistics
+ } else if (message.checkActive != null) {
+ // Check active message received
+ !this.isMain && message.checkActive
+ ? this.startCheckActive()
+ : this.stopCheckActive()
+ } else if (message.id != null && message.data != null) {
+ // Task message received
+ this.run(message)
+ } else if (message.kill === true) {
+ // Kill message received
+ this.handleKillMessage(message)