AppEngine App Deploy gives "Failed to copy file." - google-app-engine

Question

I'm deploying a Laravel app to a fresh App Engine project. But I'm getting this error constantly. I tried creating a new project and deploying too.
╔════════════════════════════════════════════════════════════╗
╠═ Uploading 9625 files to Google Cloud Storage ═╣
╚════════════════════════════════════════════════════════════╝
File upload done.
Updating service [default]...failed.
ERROR: (gcloud.app.deploy) Error Response: [3] Errors were encountered while copying files to App Engine.
Details: [
[
{
"#type": "type.googleapis.com/google.rpc.ResourceInfo",
"description": "Failed to copy file.",
"resourceName": "https://storage.googleapis.com/staging.rsvp.appspot.com/df4bc71e8832337e997291648609c4e207b5aa55",
"resourceType": "file"
}
]
]
WHat is the problem here and how can I fix it?

Answer 1

The reason for this issue was, I had some large size files ( > 30Mb ) in my project folder. I removed them and redeployed, it worked without an issue.

Answer 2

As OP already mentioned, the reason is large files. Here is how you can also find out which file is causing the problem.
If you have an error such as
Details: [
[
{
"#type": "type.googleapis.com/google.rpc.ResourceInfo",
"description": "Failed to copy file.",
"resourceName": "https://storage.googleapis.com/staging.bemmu1-hrd.appspot.com/b463c152ee1498bd4d27c1ea67c7f8e82cb4b220",
"resourceType": "file"
}
]
]
Note the hash that appears in resourceName, in this case "b463c152ee1498bd4d27c1ea67c7f8e82cb4b220".
Search for it in the most recent log file (mine was /Users/bemmu/.config/gcloud/logs/2019.07.30/00.45.43.657001.log) and you'll find it as part of a really long string, in my case:
...'templates/envato/images/arrangement.png': {'sourceUrl': 'https://storage.googleapis.com/staging.bemmu1-hrd.appspot.com/b463c152ee1498bd4d27c1ea67c7f8e82cb4b220'...
From this I could see that in my case the offending file was arrangement.png