src: MVP

Author: vwkd

src/main.ts

@@ -0,0 +1,56 @@
+export * from "./types.ts";
+import type { FeedInfo, Item } from "./types.ts";
+
+/**
+ * JSON feed
+ */
+export class Feed {
+  /** The URL of the version of the feed format */
+  #version = "https://jsonfeed.org/version/1.1";
+  /** Information of the feed */
+  #info: FeedInfo;
+  /** Items of the feed */
+  #items: Item[] = [];
+
+  /**
+   * Creates new JSON Feed
+   *
+   * @param info Feed info
+   */
+  // todo: validate arguments
+  constructor(info: FeedInfo) {
+    this.#info = info;
+  }
+
+  /**
+   * Add one or more items to the feed
+   *
+   * @param items items to add
+   * @throws {Error} if item with same ID was already added
+   */
+  // todo: validate arguments
+  add(...items: Item[]): void {
+    for (const item of items) {
+      const itemId = item.id;
+
+      if (this.#items.some(({ id }) => id === itemId)) {
+        throw new Error(`Item with ID '${itemId}' was already added`);
+      }
+    }
+
+    this.#items.push(...items);
+  }
+
+  /**
+   * Get feed as JSON
+   *
+   * @returns feed as JSON
+   */
+  toJSON(): string {
+    return JSON.stringify({
+      version: this.#version,
+      ...this.#info,
+      items: this.#items,
+    });
+  }
+}

src/types.ts

@@ -0,0 +1,120 @@
+/**
+ * Author of a feed or item
+ */
+export interface Author {
+  /** The author's name */
+  name?: string;
+  /** The URL of a site owned by the author */
+  url?: string;
+  /** The URL for an image for the author */
+  avatar?: string;
+}
+
+/**
+ * Hub for real-time notifications
+ */
+export interface Hub {
+  /** The protocol used to talk with the hub */
+  type: string;
+  /** The URL of the hub */
+  url: string;
+}
+
+/**
+ * Item with HTML and/or plain text content
+ */
+export type Item = HTMLItem | TextItem | (HTMLItem & TextItem);
+
+/**
+ * Item with HTML content
+ */
+export interface HTMLItem extends BaseItem {
+  /** HTML content of the item */
+  content_html: string;
+}
+
+/**
+ * Item with plain text content
+ */
+export interface TextItem extends BaseItem {
+  /** Plain text content of the item */
+  content_text: string;
+}
+
+/**
+ * Base item
+ */
+export interface BaseItem {
+  /** Unique identifier for the item, e.g. `url` */
+  id: string;
+  /** URL of the resource described by the item */
+  url?: string;
+  /** URL of a page elsewhere */
+  external_url?: string;
+  /** Title of the item */
+  title?: string;
+  /** Summary of the item */
+  summary?: string;
+  /** URL of the main image for the item */
+  image?: string;
+  /** URL of an image to use as a banner */
+  banner_image?: string;
+  /** Date the item was published in RFC 3339 format, e.g. `2010-02-07T14:04:00-05:00` */
+  date_published?: string;
+  /** Date the item was modified in RFC 3339 format, e.g. `2010-02-07T14:04:00-05:00` */
+  date_modified?: string;
+  /** Authors of the item */
+  authors?: Author[];
+  /** Tags associated with the item */
+  tags?: string[];
+  /** Language of the item in RFC 5646 format, e.g. `en` or `en-US` */
+  language?: string;
+  /** Attachments associated with the item */
+  attachments?: Attachment[];
+}
+
+/**
+ * Related resource of an item
+ */
+export interface Attachment {
+  /** The URL of the attachment */
+  url: string;
+  /** The MIME type of the attachment */
+  mime_type: string;
+  /** A name for the attachment */
+  title?: string;
+  /** The size of the attachment in bytes */
+  size_in_bytes?: number;
+  /** The duration of the attachment in seconds */
+  duration_in_seconds?: number;
+}
+
+/**
+ * Information of a JSON feed
+ */
+export interface FeedInfo {
+  /** The name of the feed */
+  title: string;
+  /** The URL of the resource that the feed describes */
+  home_page_url: string;
+  /** The URL of the feed */
+  feed_url: string;
+  /** Description of the feed */
+  description?: string;
+  /** Description of the purpose of the feed, ignored by the feed reader */
+  user_comment?: string;
+  /** URL of the next page of the feed for pagination, different from `feed_url` to avoid infinite loops */
+  next_url?: string;
+  /** URL of an image for the feed */
+  icon?: string;
+  /** URL of a favicon for the feed */
+  favicon?: string;
+  /** Authors of the feed */
+  authors?: Author[];
+  /** Primary language for the feed in RFC 5646 format, e.g. `en` or `en-US` */
+  language?: string;
+  /** Whether the feed is finished and won't ever update */
+  expired?: boolean;
+  /** Endpoints for real-time notifications */
+  hubs?: Hub[];
+}