runtime.sendMessage/onMessage

[hgwood]

Hello

I'm running into problems when trying to use browser.runtime.sendMessage and browser.runtime.onMessage with this polyfill on Chrome 61.

I have this code that works fine:

// in background script, run when the extension is loaded
chrome.runtime.onMessage.addListener((message, sender) => {
  console.log("background script got message", message, "from", sender);
});

// in content script, run when the user presses a button
chrome.runtime.sendMessage({type: "event", eventName: "THE_EVENT"});

If I replace chrome with browser in the background script, I get this in its console:

and the listener is not run.

Independently, if I replace chrome with browser on the content script side, I get this in the console of the page:

but the listener is run.

If I replace chrome with browser on both sides, then the content script says this instead:

and the background script message remains unchanged.

I'm new to writing browser extensions so I'm not sure if this might be a bug in the polyfill or if not using the API quite right.

[hgwood]

I think the two errors always happen but they are not reported when using chrome because they are stored in runtime.lastError, while the polyfill uses rejected promises, which do appear as console errors. So only the background script side remains a problem.

[Rob--W]

(tested with Chrome 61 and latest polyfill version (0.1.2))

If I use chrome at the content script and browser at the background script, the message gets through without errors.
If I use browser at the content script and chrome or browser at the background script, the message also gets through, but the error message is always set:

The message port closed before a response was received.

I think that we should catch this specific error and ignore it (treat it as no response).

[RuiNtD]

I got this error from the content script:

(CONTENT_SCRIPT context for ljhjkdmpfemkkhfhfakknbjogcopkebg) extensions::lastError:98: Uncaught Error: runtime namespace is null or undefined{Error: runtime namespace is null or undefined
    at assertRuntimeIsAvailable (extensions::lastError:98:11)
    at Object.clear (extensions::lastError:84:3)
    at clearLastError (extensions::messaging:62:19)
    at dispatchOnDisconnect (extensions::messaging:379:9)}

I only got the extension working with chrome in the background script and browser in the content script, but the content script error happens whenever I have browser in the content script. The trace stack is different depending on if I use chrome or browser in the background script, but the actual error remains the same. However, I never got the "Uncaught (in promise)" errors. My tests were done with Chrome 61 and polyfill version 0.2.0.

[jowa0720]

For me, it does not matter which combination of browser or chrome I use. In all cases the onMessage listener set in the background script is not executed.

If I use browser in the background script, chrome console ouputs the following when loading the background page:

If I use chrome in the the background script, the console adds an additional error:

I am using Chrome 61 and polyfill version 0.2.0.

[Rob--W]

@rpl Could you investigate? I think that it might be related to #57.

[ahmadassaf]

i can confirm that #57 fixes the issues mentioned above in a sense that browser both in content and background script will be able to communicate. However, the issue now is the sendResponse in case needed to send back an answer does not work which i believe is somehow related to #16 and a fix has been addresses in #22

[hgwood]

@ahmadassaf @Rob--W I was already using what is now named 0.2.0 when I witnessed and opened the issue, as I built the polyfill from master, so #57 was already included. I do not use sendResponse. To confirm this, I have updated by local master and rebuilt the polyfill, then diffed the new version against mine. The only difference is the version number and date in the header comment.

[hgwood]

It appears Chrome 61 might have been updated since I opened the issue. Without changing my code, here is what I now get in the content script console when I use browser on the content script side:

Looks similar to @FayneAldan and @jowa0720, but slightly different. Might be because of slightly different versions of Chrome. My version right now is 61.0.3163.100 on Windows 10 x64.

Anyway, this error does not stop the message from going through. However, the message does not get through when I use browser on the background script side. In all other cases it does. Polyfill version is still 0.2.0.

[ahmadassaf]

@hgwood i have just noticed something in my background.js that might be useful. Basically before coming across #57 i had the following:

const messageListner = typeof InstallTrigger !== 'undefined' ?  browser.runtime : chrome.extension;

Since i want my extension to work mainly in Chrome and FF, i added this check for FF and then assigning the message listener accordingly. I do no use messageListner anywhere in my codebase now .. but removing it make me get the error again .. just though to share this if it helps

[RuiNtD]

So, that would mean there's something wrong in the Proxy's get method, right? Why do we even need proxies? Why not just make an object with the available methods?

[midzelis]

Just want to chime in and say that I'm currently hitting this issue. I'm going to see if browser specific workaround posted by ahmadassaf will work for me.

[DamienCassou]

My code

• works perfectly with webextension-polyfill 0.1.2
• fails with "Previous API instantiation failed." and "Could not establish connection. Receiving end does not exist." with version 0.2.0 and Chromium 60

The popup does:

  await browser.tabs.executeScript(tabId, {file: '/browser-polyfill.min.js'})
  await browser.tabs.executeScript(tabId, {file: '/content-script.js'})
  await browser.tabs.sendMessage(tab.id, {action: 'getHeadings'})

and content-script.js is:

function messageReceived (message) {
  return Promise.resolve(...)
}

browser.runtime.onMessage.addListener(messageReceived)

I suggest using 0.1.2 for now.

[hgwood]

I confirm that 0.1.2 also works for me.

[midzelis]

My workaround was to create my own polyfill, using https://github.com/tfoxy/chrome-promise as a start, and filling in the non-callback ones with a simple re-bind from browser to chrome.

[rpl]

The fix for this issues (#64) has been included in the 0.2.1 release (https://github.com/mozilla/webextension-polyfill/releases/tag/0.2.1) and published on npm.

[ElForastero]

I'm not sure what went wrong, but I get this error too.
v0.4.0.

Both background and content scripts use browser.runtime to send and receive messages.