Isolate Seven Wonders API from sagas

2 files changed, 98 insertions, 0 deletions

diff --git a/frontend/src/api/sevenWondersApi.js b/frontend/src/api/sevenWondersApi.js
new file mode 100644
index 00000000..4ba0fff3
--- /dev/null
+++ b/frontend/src/api/sevenWondersApi.js
@@ -0,0 +1,66 @@
+import { createJsonSubscriptionChannel, createStompSession } from './websocket';
+import type { Client } from 'webstomp-client';
+import type { Channel } from 'redux-saga';
+
+const wsURL = '/seven-wonders-websocket';
+
+export class SevenWondersSession {
+  client: Client;
+
+  constructor(client: Client) {
+    this.client = client;
+  }
+
+  watchErrors(): Channel<ApiError> {
+    return createJsonSubscriptionChannel(this.client, '/user/queue/errors');
+  }
+
+  chooseName(displayName: string): void {
+    this.client.send('/app/chooseName', JSON.stringify({ playerName: displayName }));
+  }
+
+  watchNameChoice(): Channel<Object> {
+    return createJsonSubscriptionChannel(this.client, '/user/queue/nameChoice');
+  }
+
+  watchGames(): Channel<Object> {
+    return createJsonSubscriptionChannel(this.client, '/topic/games');
+  }
+
+  watchLobbyJoined(): Channel<Object> {
+    return createJsonSubscriptionChannel(this.client, '/user/queue/lobby/joined');
+  }
+
+  watchLobbyUpdated(currentGameId: number): Channel<Object> {
+    return createJsonSubscriptionChannel(this.client, `/topic/lobby/${currentGameId}/updated`);
+  }
+
+  watchGameStarted(currentGameId: number): Channel<Object> {
+    return createJsonSubscriptionChannel(this.client, `/topic/lobby/${currentGameId}/started`);
+  }
+
+  createGame(gameName: string): void {
+    this.client.send('/app/lobby/create', JSON.stringify({ gameName }));
+  }
+
+  joinGame(gameId: number): void {
+    this.client.send('/app/lobby/join', JSON.stringify({ gameId }));
+  }
+
+  startGame(): void {
+    this.client.send('/app/lobby/startGame', {});
+  }
+}
+
+export function createSession(): Promise<SevenWondersSession> {
+  return createStompSession(wsURL).then(client => new SevenWondersSession(client));
+}
+
+export class ApiError {
+  message: string;
+  details: ApiErrorDetail[];
+}
+
+export class ApiErrorDetail {
+  message: string;
+}
diff --git a/frontend/src/api/websocket.js b/frontend/src/api/websocket.js
new file mode 100644
index 00000000..6dc6e1a0
--- /dev/null
+++ b/frontend/src/api/websocket.js
@@ -0,0 +1,32 @@
+// @flow
+import SockJS from 'sockjs-client';
+import Stomp from 'webstomp-client';
+import type { Client, Frame, Subscription } from 'webstomp-client';
+
+import { eventChannel } from 'redux-saga';
+import type { Channel } from 'redux-saga';
+
+function createStompClient(url: string): Client {
+  return Stomp.over(new SockJS(url), {
+    debug: process.env.NODE_ENV !== 'production',
+  });
+}
+
+export function createStompSession(url: string, headers: Object = {}): Promise<Client> {
+  return new Promise((resolve, reject) => {
+    const client: Client = createStompClient(url);
+    const onSuccess = (frame: Frame) => resolve(client);
+    client.connect(headers, onSuccess, reject);
+  });
+}
+
+export function createJsonSubscriptionChannel(client: Client, path: string): Channel {
+  return eventChannel((emitter: (data: any) => void) => {
+    const socketSubscription: Subscription = client.subscribe(path, (frame: Frame) => {
+      // not all frames have a JSON body
+      const value = frame && frame.body && JSON.parse(frame.body);
+      emitter(value);
+    });
+    return () => socketSubscription.unsubscribe();
+  });
+}