[Question] Run headless Firefox with non-default executable path

[johnnyhuynh-dev]

I followed the "Advanced Installation" guide and found a way to download the binaries browsers into the node_modules folder of my project instead of the default path.

# Linux/macOS
$ PLAYWRIGHT_BROWSERS_PATH=0 npm i -D playwright

# Windows
$ set PLAYWRIGHT_BROWSERS_PATH=0
$ npm i -D playwright

However, when I run the script it returns an error:

browserType.launch: Failed to launch firefox because executable doesn't exist at C:\Users\johnnyhuynh007\AppData\Local\ms-playwright\firefox-1171\firefox\firefox.exe
Try re-installing playwright with "npm install playwright"

I tried to modify the option 'executablePath' in the browserType.launch([options]) but got a similar error:

browserType.launch: Failed to launch firefox because executable doesn't exist at ../node_modules/playwright/.local-browsers/firefox-1171/firefox/firefox.exe

How could I specify the path of the executable for Playwright to run correctly?

*Note: the reason I want this specific behavior is I need to upload my functions to Firebase Cloud functions, which doesn't seem to run normally with the default path option (seems like it doesn't install the browsers when it npm install package.json). By attaching the browsers to the playwright folder in node_modules and upload the whole folder, I hope it could solve the problem.

[mxschmitt]

Hi, the PLAYWRIGHT_BROWSERS_PATH=0 environment variables needs to be set during installation (npm i) and during running your actual script (node foo.js). Seems like you run your script without the required environment variable.

[johnnyhuynh-dev]

Hi, the PLAYWRIGHT_BROWSERS_PATH=0 environment variables needs to be set during installation (npm i) and during running your actual script (node foo.js). Seems like you run your script without the required environment variable.

Hi, is there any way that I can override this environment variable in the code? The Cloud Functions I am using doesn't have an option to specify an environment variable when running the script.

[mxschmitt]

// @ts-check
const playwright = require("playwright");

(async () => {
    // needs to be before the launch of the browser.
    process.env.PLAYWRIGHT_BROWSERS_PATH = "0";
    const browser = await playwright.firefox.launch();
    const context = await browser.newContext();
    const page = await context.newPage();
    await page.goto('http://whatsmyuseragent.org/');
    await page.screenshot({ path: `example.png` });
    await browser.close();
})();

Something like that should work.

[johnnyhuynh-dev]

I tried calling PLAYWRIGHT_BROWSERS_PATH=0 node theScript.js as you said and it worked perfectly. However, this process.env.PLAYWRIGHT_BROWSERS_PATH = "0"; doesn't work. Any kind of npm config or .env setting that I can set it for once and don't need to call it again?
Sorry I am not too familiar with environmental variables.

[mxschmitt]

Are you running it on Google Cloud Functions?

[johnnyhuynh-dev]

Are you running it on Google Cloud Functions?

I haven't tested on Google Cloud Functions yet, I am trying to test it on my local environment first. Do you have any suggestions for Playwright to work with GCF? All of what I am trying to do is to get it runs on GCF, and the problem with it is I can't execute something like this PLAYWRIGHT_BROWSERS_PATH=0 node foo.js on there.
As I said, GCF doesn't install the browser, and there I am trying to get around it.

[johnnyhuynh-dev]

After some more research I found that you wrote a buildpack for Heroku.

https://playwright.tech/blog/running-playwright-on-heroku

I think Firebase has a very similar issue with that, which involved the setting of environmental variables or that sort of things.

[sunaram]

Just make sure you have set the environment variable before you require the "playwright" module.
e.g. if app.js is your entry script, define
process.env.PLAYWRIGHT_BROWSERS_PATH = 0;
at the top app.js

[dgozman]

Thanks @sunaram - that should do the trick!

[rknikode]

Windows

$ set PLAYWRIGHT_BROWSERS_PATH=0
$ npm i playwright-firefox

after doing this thing still browsers installations download in shared location in userDir directory any one have idea how to resolve
OS : Windows 10

PFA