feat: recover from failed HTTP requests to third party gateways

add-on/_locales/en/messages.json

@@ -375,6 +375,14 @@
     "message": "Check before HTTP request",
     "description": "A select field option description on the Preferences screen (option_dnslinkPolicy_enabled)"
   },
+  "option_recoverViaPublicGateway_title": {
+    "message": "Recover links via public gateway",
+    "description": "An option title on the Preferences screen (option_recoverViaPublicGateway_title)"
+  },
+  "option_recoverViaPublicGateway_description": {
+    "message": "Redirect broken public gateway requests to the default public gateway",
+    "description": "An option description on the Preferences screen (option_recoverViaPublicGateway_description)"
+  },
   "option_detectIpfsPathHeader_title": {
     "message": "Detect X-Ipfs-Path Header",
     "description": "An option title on the Preferences screen (option_detectIpfsPathHeader_title)"

add-on/src/lib/ipfs-companion.js

@@ -105,6 +105,7 @@ module.exports = async function init () {
     browser.webRequest.onBeforeRequest.addListener(onBeforeRequest, { urls: ['<all_urls>'] }, ['blocking'])
     browser.webRequest.onHeadersReceived.addListener(onHeadersReceived, { urls: ['<all_urls>'] }, ['blocking', 'responseHeaders'])
     browser.webRequest.onErrorOccurred.addListener(onErrorOccurred, { urls: ['<all_urls>'] })
+    browser.webRequest.onCompleted.addListener(onCompleted, { urls: ['<all_urls>'] })
     browser.storage.onChanged.addListener(onStorageChange)
     browser.webNavigation.onCommitted.addListener(onNavigationCommitted)
     browser.webNavigation.onDOMContentLoaded.addListener(onDOMContentLoaded)
@@ -169,6 +170,10 @@ module.exports = async function init () {
     return modifyRequest.onErrorOccurred(request)
   }
 
+  function onCompleted (request) {
+    return modifyRequest.onCompleted(request)
+  }
+
   // RUNTIME MESSAGES (one-off messaging)
   // ===================================================================
   // https://developer.mozilla.org/en-US/Add-ons/WebExtensions/API/runtime/sendMessage
@@ -670,6 +675,9 @@ module.exports = async function init () {
             await browser.storage.local.set({ detectIpfsPathHeader: true })
           }
           break
+        case 'recoverViaPublicGateway':
+          state[key] = change.newValue
+          break
         case 'logNamespaces':
           shouldReloadExtension = true
           state[key] = localStorage.debug = change.newValue

add-on/src/lib/ipfs-request.js

@@ -20,6 +20,26 @@ const recoverableErrors = new Set([
   'net::ERR_INTERNET_DISCONNECTED' // no network
 ])
 
+const recoverableErrorCodes = new Set([
+  404,
+  408,
+  410,
+  415,
+  451,
+  500,
+  502,
+  503,
+  504,
+  509,
+  520,
+  521,
+  522,
+  523,
+  524,
+  525,
+  526
+])
+
 // Request modifier provides event listeners for the various stages of making an HTTP request
 // API Details: https://developer.mozilla.org/en-US/Add-ons/WebExtensions/API/webRequest
 function createRequestModifier (getState, dnslinkResolver, ipfsPathValidator, runtime) {
@@ -380,29 +400,48 @@ function createRequestModifier (getState, dnslinkResolver, ipfsPathValidator, ru
       // console.log('onErrorOccurred:' + request.error)
       // console.log('onErrorOccurred', request)
       // Check if error is final and can be recovered via DNSLink
+      let redirect
       const recoverableViaDnslink =
         state.dnslinkPolicy &&
         request.type === 'main_frame' &&
         recoverableErrors.has(request.error)
       if (recoverableViaDnslink && dnslinkResolver.canLookupURL(request.url)) {
         // Explicit call to ignore global DNSLink policy and force DNS TXT lookup
         const cachedDnslink = dnslinkResolver.readAndCacheDnslink(new URL(request.url).hostname)
-        const dnslinkRedirect = dnslinkResolver.dnslinkRedirect(request.url, cachedDnslink)
-        // We can't redirect in onErrorOccurred, so if DNSLink is present
-        // recover by opening IPNS version in a new tab
-        // TODO: add tests and demo
-        if (dnslinkRedirect) {
-          log(`onErrorOccurred: recovering using dnslink for ${request.url}`, dnslinkRedirect)
-          const currentTabId = await browser.tabs.query({ active: true, currentWindow: true }).then(tabs => tabs[0].id)
-          await browser.tabs.create({
-            active: true,
-            openerTabId: currentTabId,
-            url: dnslinkRedirect.redirectUrl
-          })
+        redirect = dnslinkResolver.dnslinkRedirect(request.url, cachedDnslink)
+        log(`onErrorOccurred: attempting to recover using dnslink for ${request.url}`, redirect)
+      }
+      // if error cannot be recovered via DNSLink
+      // direct the request to the public gateway
+      const recoverableViaPubGw = isRecoverableViaPubGw(request, state, ipfsPathValidator)
+      if (!redirect && recoverableViaPubGw) {
+        const redirectUrl = ipfsPathValidator.resolveToPublicUrl(request.url, state.pubGwURLString)
+        redirect = { redirectUrl }
+        log(`onErrorOccurred: attempting to recover using public gateway for ${request.url}`, redirect)
+      }
+      // We can't redirect in onErrorOccurred, so if DNSLink is present
+      // recover by opening IPNS version in a new tab
+      // TODO: add tests and demo
+      if (redirect) {
+        createTabWithURL(redirect, browser)
+      }
+    },
+
+    async onCompleted (request) {
+      const state = getState()
+
+      const recoverableViaPubGw =
+        isRecoverableViaPubGw(request, state, ipfsPathValidator) &&
+        recoverableErrorCodes.has(request.statusCode)
+      if (recoverableViaPubGw) {
+        const redirectUrl = ipfsPathValidator.resolveToPublicUrl(request.url, state.pubGwURLString)
+        const redirect = { redirectUrl }
+        if (redirect) {
+          log(`onErrorOccurred: attempting to recover using public gateway for ${request.url}`, redirect)
+          createTabWithURL(redirect, browser)
         }
       }
     }
-
   }
 }
 
@@ -508,3 +547,21 @@ function normalizedUnhandledIpfsProtocol (request, pubGwUrl) {
 function findHeaderIndex (name, headers) {
   return headers.findIndex(x => x.name && x.name.toLowerCase() === name.toLowerCase())
 }
+
+// utility functions for handling redirects
+// from onErrorOccurred and onCompleted
+function isRecoverableViaPubGw (request, state, ipfsPathValidator) {
+  return state.recoverViaPublicGateway &&
+    ipfsPathValidator.publicIpfsOrIpnsResource(request.url) &&
+    !request.url.startsWith(state.pubGwURLString) &&
+    request.type === 'main_frame'
+}
+
+async function createTabWithURL (redirect, browser) {
+  const currentTabId = await browser.tabs.query({ active: true, currentWindow: true }).then(tabs => tabs[0].id)
+  await browser.tabs.create({
+    active: true,
+    openerTabId: currentTabId,
+    url: redirect.redirectUrl
+  })
+}

add-on/src/lib/options.js

@@ -16,6 +16,7 @@ exports.optionDefaults = Object.freeze({
   automaticMode: true,
   linkify: false,
   dnslinkPolicy: 'best-effort',
+  recoverViaPublicGateway: false,
   detectIpfsPathHeader: true,
   preloadAtPublicGateway: true,
   catchUnhandledProtocols: true,

add-on/src/options/forms/experiments-form.js

@@ -11,6 +11,7 @@ function experimentsForm ({
   catchUnhandledProtocols,
   linkify,
   dnslinkPolicy,
+  recoverViaPublicGateway,
   detectIpfsPathHeader,
   ipfsProxy,
   logNamespaces,
@@ -22,6 +23,7 @@ function experimentsForm ({
   const onCatchUnhandledProtocolsChange = onOptionChange('catchUnhandledProtocols')
   const onLinkifyChange = onOptionChange('linkify')
   const onDnslinkPolicyChange = onOptionChange('dnslinkPolicy')
+  const onrecoverViaPublicGatewayChange = onOptionChange('recoverViaPublicGateway')
   const onDetectIpfsPathHeaderChange = onOptionChange('detectIpfsPathHeader')
   const onIpfsProxyChange = onOptionChange('ipfsProxy')
 
@@ -96,6 +98,15 @@ function experimentsForm ({
             </option>
           </select>
         </div>
+        <div>
+          <label for="recoverViaPublicGateway">
+            <dl>
+              <dt>${browser.i18n.getMessage('option_recoverViaPublicGateway_title')}</dt>
+              <dd>${browser.i18n.getMessage('option_recoverViaPublicGateway_description')}</dd>
+            </dl>
+          </label>
+          <div>${switchToggle({ id: 'recoverViaPublicGateway', checked: recoverViaPublicGateway, onchange: onrecoverViaPublicGatewayChange })}</div>
+        </div>
         <div>
           <label for="detectIpfsPathHeader">
             <dl>

add-on/src/options/page.js

@@ -75,6 +75,7 @@ module.exports = function optionsPage (state, emit) {
     catchUnhandledProtocols: state.options.catchUnhandledProtocols,
     linkify: state.options.linkify,
     dnslinkPolicy: state.options.dnslinkPolicy,
+    recoverViaPublicGateway: state.options.recoverViaPublicGateway,
     detectIpfsPathHeader: state.options.detectIpfsPathHeader,
     ipfsProxy: state.options.ipfsProxy,
     logNamespaces: state.options.logNamespaces,