Badge Request: GitHub Container Registry

[cicirello]

📋 Description

GitHub recently introduced the GitHub Container Registry (see: https://github.blog/2020-09-01-introducing-github-container-registry/). It would be nice if there were badges available similar to those that shields has for Docker image version, image size, and pulls, but for the new GitHub Container Registry.

🔗 Data

I'm not sure if GitHub has an API for this yet.

🎤 Motivation

Motivation is the same as that of the equivalent badges that already exist for Docker Hub, but targeting the GitHub Container Registry instead. Providing a nice concise visual summary of some of the key statistics one might be interested in with a Docker image, but for images available in the GCR.

[chris48s]

Given this is essentially a feature related to the package registry, I suspect this one is probably going to end up blocked on #4169 (tldr: the github tokens we have don't have the necessary scope to read package metadata) once the API endpoints are available, but we'll see..

[adriens]

🙏

[kidager]

➕

[eggplants]

To get the pull counter of the image published on ghcr, you can use PackageStatistics or PackageVersionStatistics in GraphQL API (needs auth).

To get information of tags and sizes of public images on ghcr.io, you can use https://ghcr.io/v2/ as Docker Registry HTTP API V2's endpoint like DockerHub.

Here is my example with curl:

# public image's {USER}/{IMAGE}
USER_IMAGE=eggplants/asciiquarium-docker

# get fake token ('{"token":"***"}' -> '***')
TOKEN="$(
  curl "https://ghcr.io/token?scope=repository:${USER_IMAGE}:pull" |
  awk -F'"' '$0=$4'
)"

_curl(){ curl -H "Authorization: Bearer ${TOKEN}" "$1" }

# get tags
_curl "https://ghcr.io/v2/${USER_IMAGE}/tags/list"
# >>> {"name":"eggplants/asciiquarium-docker","tags":["0.0.0","0.0","latest"]}

# get manifest of the latest image
_curl "https://ghcr.io/v2/${USER_IMAGE}/manifests/latest"
# >>>
# {
#    "mediaType": "application/vnd.docker.distribution.manifest.v2+json",
#    "schemaVersion": 2,
#    "config": {
#       "mediaType": "application/vnd.docker.container.image.v1+json",
#       "digest": "sha256:fb4552eacdc8e01082f87bae6a0fec6e1b61630f0a1e5a0e6a699d05ff0337fd",
#       "size": 5551
#    },
#    "layers": [
#       {
#          "mediaType": "application/vnd.docker.image.rootfs.diff.tar.gzip",
#          "digest": "sha256:4be315f6562fccf08fd6c749557e31e45ab6d987370e20e2c4933ddb04ddd5ff",
#          "size": 27140664
#       }, ...

[calebcartwright]

Thank you for sharing @eggplants though to be clear, this is not blocked on the basics of the api request/response, but due to the associated scopes required by github, which our tokens do not have.

This is blocked on that much bigger topic detailed in #4169

[eggplants]

The number of pulls seems difficult to fetch, but it would be relatively easy to get just the tags and their image sizes, which do not require authentication.

[calebcartwright]

The number of pulls seems difficult to fetch, but it would be relatively easy to get just the tags and their image sizes, which do not require authentication.

Gotcha, thanks for the clarification! In that case think it would probably make sense at this point to extract a separate issue for version and size badges to discuss the viability of the proposed approach, and we narrow the scope of this blocked one to pulls

[eggplants]

I have implemented eggplants/ghcr-badge on a trial basis:

[asssaf]

you can also hard code the token per image:

curl -H "Authorization: Bearer $(echo "v1:$USER_IMAGE:0" | base64)" "https://ghcr.io/v2/$USER_IMAGE/tags/list"

[eggplants]

@asssaf Thanks! eggplants/ghcr-badge@f5504c4