go-docker-image-exist

a Go application to check if a Docker image exist in a remote repository

Building

Locally

Just clone this repository into your GOPATH (who cares about GOPATH anymore ?) and go build

Docker Image

just use docker build -t go-docker-image-exist:latest .

Usage

Google Container Registry

./go-docker-image-exist -registryURL="https://us.gcr.io" -username='_token' -password=$(gcloud auth print-access-token) -logLevel=debug  -project=kube00-xxx -image=caddy/caddy -tag 0.11.0

• registry URL: the URL to reach the registry. Do not add the /v2 endpoint
  • Google: https://us.gcr.io for the US registry. Can also be https://gcr.io
• project: the GCloud project name (keep empty is no project is used)
  • Google: find your project with gcloud projects list
• username: your Registry username.
  • Google: _token
• password: your password
  • Google: get your token password with gcloud auth print-access-token
• logLevel: one of debug, info, warning, error. When using debug you will also get the HTTP calls to the Registry.
• image: full name of the remote image, including directories
• tag: the tag to search for, defaults to latest

Private (OnPrem) Gitlab registry

Gitlab use oAuth/JWT to create a token that can then be used to request the registry. All this is taken car of by https://github.com/heroku/docker-registry-client You have to create a Deploy Token in the Gitlab Settings -> Repository -> Deploy Tokens, then :

./go-docker-image-exist -username='my_deploy_token' -password='my_token_password' -logLevel=debug  -registryURL='https://your_registry_url:4567' -image=my/git_repo/my_image/name -tag v1.2.3

example

./go-docker-image-exist -registryURL="https://us.gcr.io" -username='_token' -password=$(gcloud auth print-access-token) -logLevel=debug  -project=kube00-xxx -image=caddy/caddy -tag 0.11.0 
{"level":"debug","msg":"searching image kube00-xxx/caddy/caddy","time":"2019-01-07T11:26:02-05:00"}
{"level":"debug","msg":"registry.ping url=https://us.gcr.io/v2/","time":"2019-01-07T11:26:02-05:00"}
{"level":"debug","msg":"registry.tags url=https://us.gcr.io/v2/kube00-xxx/caddy/caddy/tags/list repository=kube00-xxx/caddy/caddy","time":"2019-01-07T11:26:03-05:00"}
{"level":"debug","msg":"image kube00-xx/caddy/caddy found","time":"2019-01-07T11:26:03-05:00"}

Using the docker image

docker run -ti go-docker-image-exist:latest -registryURL="https://us.gcr.io" -username='_token' -password=$(gcloud auth print-access-token) -project=kube00-xxx -image=coyotelab/caddy -tag 0.11.0 ; echo $?
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