Can't pass a config object to the backstop command with Docker

[engelfrost]

I have a Backstop project set up where the config is exported as a function which takes an options parameter (as described in the README).

const backstop = require('backstopjs');

(async () => {
  await backstop('test', {
    docker: true,
    config: require('./backstop.config.js')(),
  })
})();

I decided to start running tests with Docker, but when I did, running the tests failed.

Delegating command to Docker... docker run --rm -it --mount type=bind,source="/Users/josef/Code/backstopSanityTest",target=/src backstopjs/backstopjs:3.8.8 test "--moby=true" "--config=[object Object]" ""

--config=[object Object] is of course not a valid configuration.

Is this an issue with the code or with the documentation?

[garris]

Does this work if you were to run backstop locally -- without the docker flag?

I have a feeling that the docker implementation (in backstop) is not compatible with this approach. My guess is that this fixable if you have the time to look into it.

[engelfrost]

Locally it works just fine, it's only when I add the Docker flag it fails. It's the combination of config object literal + Docker that causes the issue.

[garris]

Yup, thanks for confirming that. I guess to enable this the right way we would execute the config locally and pass a rendered config string/file to the docker instance? Might be a bit of work.

[engelfrost]

Yes, would it be acceptable to generate a temporary config file and delete it once the test is complete?

[garris]

Sounds good to me. Maybe create a temp file with common prefix and unique suffix name in parallel with working config file. Something like that?