commit c9bd9bb0b2d34f44c59a6f4b85266df33f7fd405 Author: David Fifield <david@bamsoftware.com> Date: Mon Feb 18 15:55:33 2019 -0700 Refactor: handle all roundtrip errors in onMessage listener. --- webextension/background.js | 55 +++++++++++++++++++++------------------------- 1 file changed, 25 insertions(+), 30 deletions(-) diff --git a/webextension/background.js b/webextension/background.js index 664e758..da3d118 100644 --- a/webextension/background.js +++ b/webextension/background.js @@ -107,39 +107,35 @@ async function roundtrip(request) { // https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/f... let url; let init = {}; - try { - if (request.url == null) { - throw new Error("missing \"url\""); - } - if (!(request.url.startsWith("http://") || request.url.startsWith("https://"))) { - throw new Error("only http and https URLs are allowed"); - } - url = request.url; - if (request.method !== "POST") { - throw new Error("only POST is allowed"); - } - init.method = request.method; - - // Don't set init.headers; that handled in the onBeforeSendHeaders - // listener. + if (request.url == null) { + throw new Error("request spec failed validation: missing \"url\""); + } + if (!(request.url.startsWith("http://") || request.url.startsWith("https://"))) { + throw new Error("request spec failed validation: only http and https URLs are allowed"); + } + url = request.url; - if (request.body != null && request.body !== "") { - init.body = base64_decode(request.body); - } + if (request.method !== "POST") { + throw new Error("request spec failed validation: only POST is allowed"); + } + init.method = request.method; - // Do not read nor write from the browser's HTTP cache. - init.cache = "no-store"; - // Don't send cookies. - init.credentials = "omit"; - // Don't follow redirects (we'll get resp.status:0 if there is one). - init.redirect = "manual"; + // Don't set init.headers; that is handled in the onBeforeSendHeaders listener. - // TODO: proxy - } catch (error) { - return {error: `request spec failed valiation: ${error.message}`}; + if (request.body != null && request.body !== "") { + init.body = base64_decode(request.body); } + // Do not read nor write from the browser's HTTP cache. + init.cache = "no-store"; + // Don't send cookies. + init.credentials = "omit"; + // Don't follow redirects (we'll get resp.status:0 if there is one). + init.redirect = "manual"; + + // TODO: proxy + // We need to use an onBeforeSendHeaders to override certain header fields, // including Host (passing them to fetch in init.headers does not work). But // onBeforeSendHeaders is a global setting (applies to all requests) and we @@ -191,9 +187,6 @@ async function roundtrip(request) { let resp = await fetch(url, init); let body = await resp.arrayBuffer(); return {status: resp.status, body: base64_encode(body)}; - } catch (error) { - // Convert any errors into an error response. - return {error: error.message}; } finally { // With certain errors (e.g. an invalid URL), the onBeforeSendHeaders // listener may never get called, and therefore never release its lock. @@ -209,6 +202,8 @@ port.onMessage.addListener((message) => { case "roundtrip": // Do a roundtrip and send the result back to the native process. roundtrip(message.request) + // Convert any error into an "error" response. + .catch(error => ({error: error.message})) .then(response => port.postMessage({id: message.id, response})); break; case "report-address":