simplification / async

src/wxBackend.ts

@@ -252,22 +252,25 @@ function makeHandlers(db: IDBDatabase,
 }
 
 
-function dispatch(handlers: any, req: any, sender: any, sendResponse: any) {
-  if (req.type in handlers) {
-    Promise
-      .resolve()
-      .then(() => {
-        const p = handlers[req.type](req.detail, sender);
+async function dispatch(handlers: any, req: any, sender: any, sendResponse: any): Promise<void> {
+  if (!(req.type in handlers)) {
+    console.error(`Request type ${JSON.stringify(req)} unknown, req ${req.type}`);
+    try {
+      sendResponse({ error: "request unknown" });
+    } catch (e) {
+      // might fail if tab disconnected
+    }
+  }
 
-        return p.then((r: any) => {
+  try {
+    const p = handlers[req.type](req.detail, sender);
+    let r = await p;
     try {
       sendResponse(r);
     } catch (e) {
       // might fail if tab disconnected
     }
-        })
-      })
-      .catch((e) => {
+  } catch (e) {
     console.log(`exception during wallet handler for '${req.type}'`);
     console.log("request", req);
     console.error(e);
@@ -277,23 +280,9 @@ function dispatch(handlers: any, req: any, sender: any, sendResponse: any) {
         hint: e.message,
         stack: e.stack.toString()
       });
-
     } catch (e) {
       // might fail if tab disconnected
     }
-      });
-    // The sendResponse call is async
-    return true;
-  } else {
-    console.error(`Request type ${JSON.stringify(req)} unknown, req ${req.type}`);
-    try {
-      sendResponse({ error: "request unknown" });
-    } catch (e) {
-      // might fail if tab disconnected
-    }
-
-    // The sendResponse call is sync
-    return false;
   }
 }
 
@@ -434,7 +423,7 @@ function clearRateLimitCache() {
   rateLimitCache = {};
 }
 
-export function wxMain() {
+export async function wxMain() {
   window.onerror = (m, source, lineno, colno, error) => {
     logging.record("error", m + error, undefined, source || "(unknown)", lineno || 0, colno || 0);
   }
@@ -517,15 +506,13 @@ export function wxMain() {
 
   chrome.extension.getBackgroundPage().setInterval(clearRateLimitCache, 5000);
 
-  Promise.resolve()
-    .then(() => {
-      return openTalerDb();
-    })
-    .catch((e) => {
-      console.error("could not open database");
-      console.error(e);
-    })
-    .then((db: IDBDatabase) => {
+  let db: IDBDatabase;
+  try {
+    db = await openTalerDb();
+  } catch (e) {
+    console.error("could not open database", e);
+    return;
+  }
   let http = new BrowserHttpLib();
   let notifier = new ChromeNotifier();
   console.log("setting wallet");
@@ -535,19 +522,8 @@ export function wxMain() {
   // script on the page
   let handlers = makeHandlers(db, wallet!);
   chrome.runtime.onMessage.addListener((req, sender, sendResponse) => {
-        try {
-          return dispatch(handlers, req, sender, sendResponse)
-        } catch (e) {
-          console.log(`exception during wallet handler (dispatch)`);
-          console.log("request", req);
-          console.error(e);
-          sendResponse({
-            error: "exception",
-            hint: e.message,
-            stack: e.stack.toString()
-          });
-          return false;
-        }
+    dispatch(handlers, req, sender, sendResponse);
+    return true;
   });
 
   // Handlers for catching HTTP requests
@@ -563,11 +539,6 @@ export function wxMain() {
         details.tabId);
     }
   }, { urls: ["<all_urls>"] }, ["responseHeaders", "blocking"]);
-    })
-    .catch((e) => {
-      console.error("could not initialize wallet messaging");
-      console.error(e);
-    });
 }