How to read file input from 'Code by Zapier' (Javascript)

Question

I'm fetching files from a Zapier trigger (with a BrickFTP app). I'm then invoking the code app (in Javascript) to process the file (parse CSV), using the 'File' attribute of the BrickFTP app as input variable to the code step but cannot successfully read the file content.

The Code step is pretty trivial:

console.log(`Got file content: ${fileContent}`);
output = {
  file: fileContent,
}

When I test the code step, I'm getting this error:

Bargle. We hit an error creating a run javascript. :-( Error: 
[LazyFile] (3587 bytes) https://zapier.com/engine/hydrate/691575/.eJwtkFFrwjAUhf_KuM9i1mq3WRhjohSERjaqw76ULL2apG3aJVFR6X9fKr4evnu-w72B1NYxzbGQJcRh9BZFs2A6gr3Euiw0axBiKPFU7GWNMAIukFdFhReIX2ZB9Br5qNUOtSvcpRtg6qnqzMzBQnyDo6l9JpzrbEwI67rxr5G82rtuzNvGB5IYtI6cAjIYLCFSE-eTMbenD8adbPW7wVIa5M43PySPNQ065i39CAz-Hf3VoBTISjR3--fRidbIKxtq_NmcWcmf0uthQputyrPlOVfLyU5tAqpok_5spnSxklTNZZ7x53Um1DrZql0mGprsLrlKPT-vafItUrUSNPyaeFakYRqtF90U-vsi0fpPQrLMoO_7f_ftdsQ:1do4Qj:pEkOihXff9eAzu8eLyTpN378vgI/ is not JSON serializable

Screenshots:

The test data

Test results

Answer 1

I had the same problem, and that was because the field type I was assigning was text rather than file. First, you have to use CLI version of Zapier, and then if a field is supposed to accept files, it must be of type 'file'. In this way, the url of the file is being returned and can be downloaded.