federating my verse (iceshrimp & mastodon API compat, read-only)

src/instance.js

@@ -0,0 +1,107 @@
+import Post from './post/post.js';
+
+let instance;
+
+const ERR_UNSUPPORTED = "Unsupported server";
+const ERR_SERVER_RESPONSE = "Unsupported response from the server";
+
+export default class Instance {
+    #host;
+    #token;
+    #type;
+    #secure;
+
+    static types = {
+        ICESHRIMP: "iceshrimp",
+        MASTODON: "mastodon",
+        MISSKEY: "misskey",
+        AKKOMA: "akkoma",
+    };
+
+    static get_instance() {
+        if (!instance) instance = new Instance();
+        return instance;
+    }
+
+    static async setup(host, token, secure) {
+        instance = Instance.get_instance();
+        instance.host = host;
+        instance.token = token;
+        instance.secure = secure;
+        await instance.#guess_type();
+    }
+
+    async #guess_type() {
+        const url = instance.#proto + instance.host + "/api/v1/instance";
+        console.log("Snooping for instance information at " + url + "...");
+        const res = await fetch(url);
+        const data = await res.json();
+        const version = data.version.toLowerCase();
+
+        instance.type = Instance.types.MASTODON;
+        if (version.search("iceshrimp") !== -1) instance.type = Instance.types.ICESHRIMP;
+        if (version.search("misskey") !== -1) instance.type = Instance.types.MISSKEY;
+        if (version.search("akkoma") !== -1) instance.type = Instance.types.AKKOMA;
+
+        console.log("Assumed server type to be \"" + instance.type + "\".");
+    }
+
+    static async get_timeline(last_post_id) {
+        let data = null;
+        switch (instance.type) {
+            case Instance.types.ICESHRIMP:
+                data = await instance.#get_timeline_iceshrimp(last_post_id);
+                break;
+            case Instance.types.MASTODON:
+                data = await instance.#get_timeline_mastodon(last_post_id);
+                break;
+            default:
+                console.error(ERR_UNSUPPORTED);
+                return null;
+        }
+        if (data.constructor != Array) {
+            console.error(ERR_SERVER_RESPONSE);
+            return null;
+        }
+        let posts = [];
+        data.forEach(post_data => {
+            const post = Post.parse(post_data);
+            if (!post) return;
+            posts = [...posts, post];
+        });
+        return posts;
+    }
+
+    async #get_timeline_iceshrimp(last_post_id) {
+        let body = Object;
+        if (last_post_id) body.untilId = last_post_id;
+        const res = await fetch(this.#proto + this.host + "/api/notes/timeline", {
+            method: 'POST',
+            headers: { "Authorization": "Bearer " + this.token },
+            body: JSON.stringify(body)
+        });
+        return await res.json();
+    }
+
+    async #get_timeline_mastodon(last_post_id) {
+        let url = this.#proto + this.host + "/api/v1/timelines/home";
+        if (last_post_id) url += "?max_id=" + last_post_id;
+        const res = await fetch(url, {
+            method: 'GET',
+            headers: { "Authorization": "Bearer " + this.token }
+        });
+        return await res.json();
+    }
+
+    get #proto() {
+        if (this.secure) return "https://";
+        return "http://";
+    }
+
+    static get ok() {
+        if (!instance) return false;
+        if (!instance.host) return false;
+        if (!instance.token) return false;
+        return true;
+    }
+}