fix: restore ESR compatibility

.babelrc

@@ -7,7 +7,7 @@
       "@babel/preset-env",
       {
         "targets": {
-          "firefox": 69,
+          "firefox": 68,
           "chrome": 72
         }
       }

add-on/manifest.firefox.json

@@ -8,7 +8,7 @@
   "applications": {
     "gecko": {
       "id": "ipfs-firefox-addon@lidel.org",
-      "strict_min_version": "69.0"
+      "strict_min_version": "68.0"
     }
   },
   "page_action": {

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

@@ -24,6 +24,9 @@ const recoverableNetworkErrors = new Set([
 ])
 const recoverableHttpError = (code) => code && code >= 400
 
+// Tracking late redirects for edge cases such as https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+const onHeadersReceivedRedirect = new Set()
+
 // 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) {
@@ -311,6 +314,19 @@ function createRequestModifier (getState, dnslinkResolver, ipfsPathValidator, ru
       }
 
       if (state.redirect) {
+        // Late redirect as a workaround for edge cases such as:
+        // - CORS XHR in Firefox: https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+        if (runtime.requiresXHRCORSfix && onHeadersReceivedRedirect.has(request.requestId)) {
+          onHeadersReceivedRedirect.delete(request.requestId)
+          if (state.dnslinkPolicy) {
+            const dnslinkRedirect = dnslinkResolver.dnslinkRedirect(request.url)
+            if (dnslinkRedirect) {
+              return dnslinkRedirect
+            }
+          }
+          return redirectToGateway(request.url, state, ipfsPathValidator)
+        }
+
         // Detect X-Ipfs-Path Header and upgrade transport to IPFS:
         // 1. Check if DNSLink exists and redirect to it.
         // 2. If there is no DNSLink, validate path from the header and redirect
@@ -404,6 +420,11 @@ function createRequestModifier (getState, dnslinkResolver, ipfsPathValidator, ru
         }
       }
 
+      // Cleanup after https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+      if (runtime.requiresXHRCORSfix && onHeadersReceivedRedirect.has(request.requestId)) {
+        onHeadersReceivedRedirect.delete(request.requestId)
+      }
+
       // Check if error can be recovered by opening same content-addresed path
       // using active gateway (public or local, depending on redirect state)
       if (isRecoverable(request, state, ipfsPathValidator)) {
@@ -463,6 +484,20 @@ function isSafeToRedirect (request, runtime) {
     return false
   }
 
+  // Ignore XHR requests for which redirect would fail due to CORS bug in Firefox
+  // See: https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+  if (runtime.requiresXHRCORSfix && request.type === 'xmlhttprequest' && !request.responseHeaders) {
+    // Sidenote on XHR Origin: Firefox 60 uses request.originUrl, Chrome 63 uses request.initiator
+    if (request.originUrl) {
+      const sourceOrigin = new URL(request.originUrl).origin
+      const targetOrigin = new URL(request.url).origin
+      if (sourceOrigin !== targetOrigin) {
+        log('Delaying redirect of CORS XHR until onHeadersReceived due to https://github.com/ipfs-shipyard/ipfs-companion/issues/436 :', request.url)
+        onHeadersReceivedRedirect.add(request.requestId)
+        return false
+      }
+    }
+  }
   return true
 }
 

add-on/src/lib/runtime-checks.js

@@ -6,7 +6,7 @@ function getBrowserInfo (browser) {
   if (browser && browser.runtime && browser.runtime.getBrowserInfo) {
     return browser.runtime.getBrowserInfo()
   }
-  return Promise.resolve()
+  return Promise.resolve({})
 }
 
 function getPlatformInfo (browser) {
@@ -28,21 +28,20 @@ function hasChromeSocketsForTcp () {
 
 async function createRuntimeChecks (browser) {
   // browser
-  const browserInfo = await getBrowserInfo(browser)
-  const runtimeBrowserName = browserInfo ? browserInfo.name : 'unknown'
-  const runtimeIsFirefox = !!(runtimeBrowserName.includes('Firefox') || runtimeBrowserName.includes('Fennec'))
-  const runtimeHasNativeProtocol = !!(browser && browser.protocol && browser.protocol.registerStringProtocol)
+  const { name, version } = await getBrowserInfo(browser)
+  const isFirefox = name && (name.includes('Firefox') || name.includes('Fennec'))
+  const hasNativeProtocolHandler = !!(browser && browser.protocol && browser.protocol.registerStringProtocol)
   // platform
   const platformInfo = await getPlatformInfo(browser)
-  const runtimeIsAndroid = platformInfo ? platformInfo.os === 'android' : false
-  const runtimeHasSocketsForTcp = hasChromeSocketsForTcp()
+  const isAndroid = platformInfo ? platformInfo.os === 'android' : false
   return Object.freeze({
     browser,
-    isFirefox: runtimeIsFirefox,
-    isAndroid: runtimeIsAndroid,
-    isBrave: runtimeHasSocketsForTcp, // TODO: make it more robust
-    hasChromeSocketsForTcp: runtimeHasSocketsForTcp,
-    hasNativeProtocolHandler: runtimeHasNativeProtocol
+    isFirefox,
+    isAndroid,
+    isBrave: hasChromeSocketsForTcp(), // TODO: make it more robust
+    requiresXHRCORSfix: !!(isFirefox && version && version.startsWith('68')),
+    hasChromeSocketsForTcp: hasChromeSocketsForTcp(),
+    hasNativeProtocolHandler
   })
 }
 

test/functional/lib/ipfs-request-dnslink.test.js

@@ -183,6 +183,20 @@ describe('modifyRequest processing', function () {
       const xhrRequest = { url: 'http://explore.ipld.io/index.html?argTest#hashTest', type: 'xmlhttprequest', originUrl: 'https://www.nasa.gov/foo.html', requestId: fakeRequestId() }
       expect(modifyRequest.onBeforeRequest(xhrRequest).redirectUrl).to.equal(activeGateway + '/ipns/explore.ipld.io/index.html?argTest#hashTest')
     })
+    it('should redirect later in onHeadersReceived if dnslink exists, XHR is cross-origin and runtime is Firefox <69', function () {
+      // stub existence of a valid DNS record
+      const fqdn = 'explore.ipld.io'
+      dnslinkResolver.readDnslinkFromTxtRecord = sinon.stub().withArgs(fqdn).returns('/ipfs/QmbfimSwTuCvGL8XBr3yk1iCjqgk2co2n21cWmcQohymDd')
+      //
+      // Context for CORS XHR problems in Firefox <69: https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+      runtime.requiresXHRCORSfix = true
+      // Firefox uses 'originUrl' for origin
+      const xhrRequest = { url: 'http://explore.ipld.io/index.html?argTest#hashTest', type: 'xmlhttprequest', originUrl: 'https://www.nasa.gov/foo.html', requestId: fakeRequestId() }
+      // onBeforeRequest should not change anything, as it will trigger false-positive CORS error
+      expect(modifyRequest.onBeforeRequest(xhrRequest)).to.equal(undefined)
+      // onHeadersReceived is after CORS validation happens, so its ok to cancel and redirect late
+      expect(modifyRequest.onHeadersReceived(xhrRequest).redirectUrl).to.equal(activeGateway + '/ipns/explore.ipld.io/index.html?argTest#hashTest')
+    })
     it('should do nothing if dnslink does not exist and XHR is cross-origin in Firefox', function () {
       // stub no dnslink
       const fqdn = 'youtube.com'
@@ -286,6 +300,19 @@ describe('modifyRequest processing', function () {
           xhrRequest.responseHeaders = [{ name: 'X-Ipfs-Path', value: '/ipfs/QmbfimSwTuCvGL8XBr3yk1iCjqgk2co2n21cWmcQohymDd' }]
           expect(modifyRequest.onHeadersReceived(xhrRequest).redirectUrl).to.equal(activeGateway + '/ipns/explore.ipld.io/index.html?argTest#hashTest')
         })
+        it('should redirect later in onHeadersReceived if XHR is cross-origin and runtime is Firefox <69', function () {
+          // stub existence of a valid DNS record
+          const fqdn = 'explore.ipld.io'
+          dnslinkResolver.setDnslink(fqdn, '/ipfs/QmbfimSwTuCvGL8XBr3yk1iCjqgk2co2n21cWmcQohymDd')
+          //
+          // Context for CORS XHR problems in Firefox <69: https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+          runtime.requiresXHRCORSfix = true
+          const xhrRequest = { url: 'http://explore.ipld.io/index.html?argTest#hashTest', type: 'xmlhttprequest', originUrl: 'https://www.nasa.gov/foo.html', requestId: fakeRequestId() }
+          // onBeforeRequest should not change anything, as it will trigger false-positive CORS error
+          expect(modifyRequest.onBeforeRequest(xhrRequest)).to.equal(undefined)
+          // onHeadersReceived is after CORS validation happens, so its ok to cancel and redirect late
+          expect(modifyRequest.onHeadersReceived(xhrRequest).redirectUrl).to.equal(activeGateway + '/ipns/explore.ipld.io/index.html?argTest#hashTest')
+        })
         // Test makes more sense for dnslinkPolicy=enabled, but we keep it here for completeness
         it('should do nothing if DNS TXT record is missing and XHR is cross-origin in Firefox', function () {
           // stub no dnslink

test/functional/lib/ipfs-request-gateway-redirect.test.js

@@ -160,6 +160,36 @@ describe('modifyRequest.onBeforeRequest:', function () {
         expect(modifyRequest.onBeforeRequest(xhrRequest).redirectUrl).to.equal('https://ipfs.io/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest')
       })
     })
+    describe('with external node when runtime.requiresXHRCORSfix', function () {
+      beforeEach(function () {
+        state.ipfsNodeType = 'external'
+        browser.runtime.getBrowserInfo = () => Promise.resolve({ name: 'Firefox', version: '68.0.0' })
+      })
+      it('should be served from custom gateway if fetched from the same origin and redirect is enabled in Firefox', function () {
+        runtime.isFirefox = true
+        const xhrRequest = { url: 'https://google.com/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest', type: 'xmlhttprequest', originUrl: 'https://google.com/' }
+        expect(modifyRequest.onBeforeRequest(xhrRequest).redirectUrl).to.equal('http://127.0.0.1:8080/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest')
+      })
+      it('should be served from custom gateway if fetched from the same origin and redirect is enabled in non-Firefox', function () {
+        runtime.isFirefox = false
+        const xhrRequest = { url: 'https://google.com/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest', type: 'xmlhttprequest', initiator: 'https://google.com/' }
+        expect(modifyRequest.onBeforeRequest(xhrRequest).redirectUrl).to.equal('http://127.0.0.1:8080/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest')
+      })
+      it('should be served from custom gateway if XHR is cross-origin and redirect is enabled in non-Firefox', function () {
+        runtime.isFirefox = false
+        const xhrRequest = { url: 'https://google.com/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest', type: 'xmlhttprequest', initiator: 'https://www.nasa.gov/foo.html', requestId: fakeRequestId() }
+        expect(modifyRequest.onBeforeRequest(xhrRequest).redirectUrl).to.equal('http://127.0.0.1:8080/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest')
+      })
+      it('should be served from custom gateway via late redirect in onHeadersReceived if XHR is cross-origin and redirect is enabled in Firefox', function () {
+        // Context for CORS XHR problems in Firefox: https://github.com/ipfs-shipyard/ipfs-companion/issues/436
+        runtime.isFirefox = true
+        const xhrRequest = { url: 'https://google.com/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest', type: 'xmlhttprequest', originUrl: 'https://www.nasa.gov/foo.html', requestId: fakeRequestId() }
+        // onBeforeRequest should not change anything, as it will trigger false-positive CORS error
+        expect(modifyRequest.onBeforeRequest(xhrRequest)).to.equal(undefined)
+        // onHeadersReceived is after CORS validation happens, so its ok to cancel and redirect late
+        expect(modifyRequest.onHeadersReceived(xhrRequest).redirectUrl).to.equal('http://127.0.0.1:8080/ipfs/QmbWqxBEKC3P8tqsKc98xmWNzrzDtRLMiMPL8wBuTGsMnR?argTest#hashTest')
+      })
+    })
   })
 
   describe('request for a path matching /ipns/{path}', function () {

test/functional/lib/runtime-checks.test.js

@@ -5,6 +5,7 @@ const { describe, it, before, beforeEach, after } = require('mocha')
 const { expect } = require('chai')
 const browser = require('sinon-chrome')
 const { createRuntimeChecks, hasChromeSocketsForTcp } = require('../../../add-on/src/lib/runtime-checks')
+const promiseStub = (result) => () => Promise.resolve(result)
 
 describe('runtime-checks.js', function () {
   before(() => {
@@ -21,14 +22,6 @@ describe('runtime-checks.js', function () {
       browser.flush()
     })
 
-    // current version of sinon-chrome is missing stubs for some APIs,
-    // this is a workaround until fix is provided upstream
-    function promiseStub (result) {
-      return () => {
-        return Promise.resolve(result)
-      }
-    }
-
     it('should return true when in Firefox runtime', async function () {
       browser.runtime.getBrowserInfo = promiseStub({ name: 'Firefox' })
       const runtime = await createRuntimeChecks(browser)
@@ -42,6 +35,30 @@ describe('runtime-checks.js', function () {
     })
   })
 
+  describe('requiresXHRCORSfix', function () {
+    beforeEach(function () {
+      browser.flush()
+    })
+
+    it('should return true when in Firefox runtime < 69', async function () {
+      browser.runtime.getBrowserInfo = promiseStub({ name: 'Firefox', version: '68.0.0' })
+      const runtime = await createRuntimeChecks(browser)
+      expect(runtime.requiresXHRCORSfix).to.equal(true)
+    })
+
+    it('should return false when in Firefox runtime >= 69', async function () {
+      browser.runtime.getBrowserInfo = promiseStub({ name: 'Firefox', version: '69.0.0' })
+      const runtime = await createRuntimeChecks(browser)
+      expect(runtime.requiresXHRCORSfix).to.equal(false)
+    })
+
+    it('should return false when  if getBrowserInfo is not present', async function () {
+      browser.runtime.getBrowserInfo = undefined
+      const runtime = await createRuntimeChecks(browser)
+      expect(runtime.requiresXHRCORSfix).to.equal(false)
+    })
+  })
+
   describe('isAndroid', function () {
     beforeEach(function () {
       browser.flush()