1 files changed, 118 insertions, 0 deletions
diff --git a/src/util/connections/Connection.ts b/src/util/connections/Connection.ts
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+++ b/src/util/connections/Connection.ts
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+/*
+	Spacebar: A FOSS re-implementation and extension of the Discord.com backend.
+	Copyright (C) 2023 Spacebar and Spacebar Contributors
+	
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Affero General Public License as published
+	by the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+	
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Affero General Public License for more details.
+	
+	You should have received a copy of the GNU Affero General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+import crypto from "crypto";
+import { ConnectedAccount } from "../entities";
+import { ConnectedAccountSchema, ConnectionCallbackSchema } from "../schemas";
+import { Config, DiscordApiErrors } from "../util";
+
+/**
+ * A connection that can be used to connect to an external service.
+ */
+export default abstract class Connection {
+	id: string;
+	settings: { enabled: boolean };
+	states: Map<string, string> = new Map();
+
+	abstract init(): void;
+
+	/**
+	 * Generates an authorization url for the connection.
+	 * @param args
+	 */
+	abstract getAuthorizationUrl(userId: string): string;
+
+	/**
+	 * Returns the redirect_uri for a connection type
+	 * @returns redirect_uri for this connection
+	 */
+	getRedirectUri() {
+		const endpointPublic =
+			Config.get().api.endpointPublic ?? "http://localhost:3001";
+		return `${endpointPublic}/connections/${this.id}/callback`;
+	}
+
+	/**
+	 * Processes the callback
+	 * @param args Callback arguments
+	 */
+	abstract handleCallback(
+		params: ConnectionCallbackSchema,
+	): Promise<ConnectedAccount | null>;
+
+	/**
+	 * Gets a user id from state
+	 * @param state the state to get the user id from
+	 * @returns the user id associated with the state
+	 */
+	getUserId(state: string): string {
+		if (!this.states.has(state)) throw DiscordApiErrors.INVALID_OAUTH_STATE;
+		return this.states.get(state) as string;
+	}
+
+	/**
+	 * Generates a state
+	 * @param user_id The user id to generate a state for.
+	 * @returns a new state
+	 */
+	createState(userId: string): string {
+		const state = crypto.randomBytes(16).toString("hex");
+		this.states.set(state, userId);
+
+		return state;
+	}
+
+	/**
+	 * Takes a state and checks if it is valid, and deletes it.
+	 * @param state The state to check.
+	 */
+	validateState(state: string): void {
+		if (!this.states.has(state)) throw DiscordApiErrors.INVALID_OAUTH_STATE;
+		this.states.delete(state);
+	}
+
+	/**
+	 * Creates a Connected Account in the database.
+	 * @param data connected account data
+	 * @returns the new connected account
+	 */
+	async createConnection(
+		data: ConnectedAccountSchema,
+	): Promise<ConnectedAccount> {
+		const ca = ConnectedAccount.create({ ...data });
+		await ca.save();
+		return ca;
+	}
+
+	/**
+	 * Checks if a user has an exist connected account for the given extenal id.
+	 * @param userId the user id
+	 * @param externalId the connection id to find
+	 * @returns
+	 */
+	async hasConnection(userId: string, externalId: string): Promise<boolean> {
+		const existing = await ConnectedAccount.findOne({
+			where: {
+				user_id: userId,
+				external_id: externalId,
+			},
+		});
+
+		return !!existing;
+	}
+}