Add thread class mapping

src/scripts/classes/thread.ts

@@ -0,0 +1,227 @@
+"use strict";
+
+// Public modules from npm
+import cheerio from "cheerio";
+
+// Modules from files
+import Post from "./post";
+import PlatformUser from "./platform-user";
+import { TRating } from "../interfaces";
+import { urls } from "../constants/url";
+import { THREAD } from "../constants/css-selector";
+import { fetchHTML, fetchPOSTResponse } from "../network-helper";
+import Shared from "../shared";
+import { GenericAxiosError, UnexpectedResponseContentType } from "./errors";
+import { Result } from "./result";
+import { getJSONLD, TJsonLD } from "../scrape-data/json-ld";
+
+/**
+ * Represents a generic F95Zone platform thread.
+ */
+export default class Thread {
+
+    //#region Fields
+
+    private _id: number;
+    private _url: string;
+    private _title: string;
+    private _tags: string[];
+    private _prefixes: string[];
+    private _posts: Post[];
+    private _rating: TRating;
+    private _owner: PlatformUser;
+    private _creation: Date;
+
+    //#endregion Fields
+
+    //#region Getters
+
+    /**
+     * Unique ID of the thread on the platform.
+     */
+    public get id() { return this._id; }
+    /**
+     * URL of the thread.
+     * 
+     * It may vary depending on any versions of the contained product.
+     */
+    public get url() { return this._url; }
+    /**
+     * Thread title.
+     */
+    public get title() { return this._title; };
+    /**
+     * Tags associated with the thread.
+     */
+    public get tags() { return this._tags; }
+    /**
+     * Prefixes associated with the thread
+     */
+    public get prefixes() { return this._prefixes; }
+    /**
+     * List of posts belonging to the thread.
+     */
+    public get posts() { return this._posts; }
+    /**
+     * Rating assigned to the thread.
+     */
+    public get rating() { return this._rating; }
+    /**
+     * Owner of the thread.
+     */
+    public get owner() { return this._owner; }
+    /**
+     * Creation date of the thread.
+     */
+    public get creation() { return this._creation; }
+
+    //#endregion Getters
+
+    /**
+     * Initializes an object for mapping a thread. 
+     * 
+     * The unique ID of the thread must be specified.
+     */
+    constructor(id: number) { this._id = id; }
+
+    //#region Private methods
+
+    /**
+     * Set the number of posts to display for the current thread.
+     */
+    private async setMaximumPostsForPage(n: 20 | 40 | 60 | 100): Promise<void> {
+        // Prepare the parameters to send via POST request
+        const params = {
+            "_xfResponseType": "json",
+            "_xfRequestUri": `/account/dpp-update?content_type=thread&content_id=${this.id}`,
+            "_xfToken": Shared.session.token,
+            "_xfWithData": "1",
+            "content_id": this.id.toString(),
+            "content_type": "thread",
+            "dpp_custom_config[posts]": n.toString(),
+        };
+
+        // Send POST request
+        const response = await fetchPOSTResponse(urls.F95_POSTS_NUMBER, params);
+        if (response.isFailure()) throw response.value;
+    }
+
+    /**
+     * Gets all posts on a page.
+     */
+    private async parsePostsInPage(html: string): Promise<Post[]> {
+        // Load the HTML
+        const $ = cheerio.load(html);
+
+        // Start parsing the posts
+        const postPromises = $(THREAD.POSTS_IN_PAGE)
+            .toArray()
+            .map(async (idx, el) => {
+                // Parse post data
+                const p = new Post();
+                await p.fetchData($(el));
+
+                return p;
+            });
+
+        // Wait for the post to be fetched
+        return await Promise.all(postPromises);
+    }
+
+    /**
+     * Gets all posts in the thread.
+     */
+    private async fetchPosts(pages: number): Promise<Post[]> {
+        // Local variables
+        type TFetchResult = Promise<Result<GenericAxiosError | UnexpectedResponseContentType, string>>;
+        const htmlPromiseList: TFetchResult[] = [];
+        const fetchedPosts: Post[] = [];
+
+        // Set the maximum number of post to 100
+        await this.setMaximumPostsForPage(100);
+
+        // Fetch posts for every page in the thread
+        for (let i = 1; i <= pages; i++) {
+            // Prepare the URL
+            const url = new URL(`page-${i}`, urls.F95_BASE_URL).toString();
+
+            // Fetch the HTML source
+            const htmlResponse = fetchHTML(url);
+            htmlPromiseList.push(htmlResponse);
+        }
+
+        // Wait for all the pages to load
+        const responses = await Promise.all(htmlPromiseList);
+
+        // Scrape the pages
+        for (const response of responses) {
+            if (response.isSuccess()) {
+                // Parse the posts
+                const posts = await this.parsePostsInPage(response.value);
+
+                fetchedPosts.push(...posts);
+            } else throw response.value;
+        }
+        
+        // Sorts the list of posts
+        return fetchedPosts.sort((a, b) => (a.id > b.id) ? 1 : ((b.id > a.id) ? -1 : 0));
+    }
+
+    /**
+     * It processes the rating of the thread 
+     * starting from the data contained in the JSON+LD tag.
+     */
+    private parseRating(data: TJsonLD): TRating {
+        const ratingTree = data["aggregateRating"] as TJsonLD;
+        const rating: TRating = {
+            average: parseFloat(ratingTree["ratingValue"] as string),
+            best: parseInt(ratingTree["bestRating"] as string),
+            count: parseInt(ratingTree["ratingCount"] as string),
+        };
+
+        return rating;
+    }
+
+    //#endregion Private methods
+
+    //#region Public methods
+
+    /**
+     * Gets information about this thread.
+     */
+    public async fetch() {
+        // Prepare the url
+        this._url = new URL(this.id.toString(), urls.F95_BASE_URL).toString();
+
+        // Fetch the HTML source
+        const htmlResponse = await fetchHTML(this.url);
+
+        if (htmlResponse.isSuccess()) {
+            // Load the HTML
+            const $ = cheerio.load(htmlResponse.value);
+
+            // Fetch data from selectors
+            const creationDatetime = $(THREAD.CREATION).attr("datetime");
+            const ownerID = $(THREAD.OWNER_ID).attr("data-user-id");
+            const tagArray = $(THREAD.TAGS).toArray();
+            const prefixArray = $(THREAD.PREFIXES).toArray();
+            const JSONLD = getJSONLD($("body"));
+
+            // Parse the thread's data
+            this._title = $(THREAD.TITLE).text();
+            this._creation = new Date(creationDatetime);
+            this._tags = tagArray.map(el => $(el).text().trim());
+            this._prefixes = prefixArray.map(el => $(el).text().trim());
+            this._owner = new PlatformUser(parseInt(ownerID));
+            this._rating = this.parseRating(JSONLD);
+
+            // Parse all the posts
+            const pages = parseInt($(THREAD.LAST_PAGE).first().text());
+            this._posts = await this.fetchPosts(pages);
+
+        } else throw htmlResponse.value;
+    }
+
+    //#endregion Public methods
+
+}