Docker push to AWS ECR fails on Windows: no basic auth credentials

One of my searches led me to this answer, which while irrelevant to my case, brought to my attention the place where authentication credentials are stored: the docker config.json file. Take a look here to read more about it and its auth usage.

However, my own file had these contents after logging in with any of the methods above:

{
    "auths": {
        "https://123456789.dkr.ecr.us-east-1.amazonaws.com": {}
    },
    "credsStore": "wincred"
}

The explicit mention of Windows (wincred) caught my attention. Reading more into this, it appears docker on Windows uses a helper credential store which is probably better than storing credentials as plain text on the file system (it's normally stored as base64 which is greek for "plain text").

However - the solution came when I manually edited this file to contain the authentication token directly.

I generated my authentication token with this command (output shortened for brevity):

$ aws --profile myprofile ecr get-authorization-token --region us-east-1 --output text --query authorizationData[].authorizationToken
jFHNnVxZ............Vqc==

After editing ~/.docker/config.json, it looked something like this:

{
    "auths": {
        "https://123456789.dkr.ecr.us-east-1.amazonaws.com": {
            "auth": "jFHNnVxZ............Vqc=="
        }
    }
}

And with this in place, the push is finally successful:

$ docker push 123456789.dkr.ecr.us-east-1.amazonaws.com/myrepo:latest
The push refers to a repository [123456789.dkr.ecr.us-east-1.amazonaws.com/myrepo]
61a69688f56d: Pushed
11ad4908e16e: Pushed
myrepo: digest: sha256:20c0f3......82aa19 size: 42162

And all is well once more.

Extending your own brilliant answer which got me out of jail. I found that if you remove:

,
"credsStore": "wincred"

Save the file, run the docker login command again it will put the credentials directly in config.json which I found to work.

Leaving something a little like

{
    "auths": {
        "https://407163548648.dkr.ecr.eu-west-1.amazonaws.com": {
            "auth": "QV...Nbz0=",
            "email": "AWS"
        }
    }
}