cru

README

CRU

Container Reference Updater - updates container image references

Update kubernetes manifests, Terraform configuration files, or any other file with the required container image reference.

If can work on a remote git repository, a local git workspace or a directory.

cru can also run as a service, to allow clients to update the image references in a git repository, without requiring complete write access to the repository.

Usage

Usage:
  cru list   [--verbose] [--no-filename] [--repository=URL [--branch=BRANCH]  [(--username=USERNAME --email=EMAIL)] ] [PATH] ...
  cru update [--verbose] [--dry-run] [(--resolve-digest|--resolve-tag)] [--repository=URL [--branch=BRANCH] [(--username=USERNAME --email=EMAIL)] [--commit=MESSAGE]] (--all | --image-reference=REFERENCE ...) (--matching-tag) [PATH] ...
  cru serve  [--verbose] [--dry-run] [--port=PORT] --repository=URL --branch=BRANCH [(--username=USERNAME --email=EMAIL)]  [PATH] ...

Options

--dry-run           pretend to run the update, make no changes.
--verbose           show more output.

--no-filename       do not print the filename.

--all               replace all container image reference tags with "latest"
--image-reference=REFERENCE to update.
--matching-tag      match the container image reference on the tag, not just the repository.
--resolve-digest    change the image reference tag to a reference of the digest of the image.
--resolve-tag       change the image reference tag to the first alternate tag of the reference.

--commit=MESSAGE    commit the changes with the specified message.
--repository=URL    to read and/or update.
--branch=BRANCH     to update.
--username=USERNAME to use for the commit [default: cru].
--email=EMAIL       to use for the commit [default: cru@binx.io].

--port=PORT         to listen on, defaults to 8080 or PORT environment variable.

Examples

In the following paragraphs you will find a number of examples of the use of cru.

listing container image references

Search for image references in the current directory

$: cru list .
README.md: eu.gcr.io/binxio/paas-monitor:v0.3.1
README.md: eu.gcr.io/binxio/paas-monitor:v0.3.2
README.md: eu.gcr.io/binxio/paas-monitor:v1.0.0
README.md: gcr.io/my-project/my-app:v1.2
README.md: gcr.io/my-project/my-app@sha256:70d23423bdb3e4e63255cf62747b5cbfce53210778ca2fc3a2544595a0fce3c6
README.md: gcr.io/my-project/my-app@sha256:9550c0b587e1e07fda5a7bd210a44d868f038944a86fe77673ea613d57d62ef9
README.md: gcr.io/my-project/my-worker@sha256:2a2df1d263e73f6a2cc16a9e4aefe8b44563b74d2f1dca067ba167da1198216c
list_test.go: gcr.io/binxio/paas-monitor:v0.3.1
update_test.go: gcr.io/binxio/paas-monitor:v0.3.1
update_test.go: gcr.io/binxio/paas-monitor:v0.3.2
update_test.go: gcr.io/binxio/paas-monitor:v1.0.0

updating specific container image references

Update all image references of eu.gcr.io/binxio/paas-monitor:v3.2.4-5-g49d6871 in the file ref/update_test.go:

$ cru update --image-reference eu.gcr.io/binxio/paas-monitor:v3.2.4-5-g49d6871 ref/update_test.go
2020/06/23 13:19:11 INFO: updating ref/update_test.go

updating specific container image reference with digest

Update a specific image reference with the exact digest, add --resolve-digest:

$ cru update --resolve-digest --image-reference gcr.io/binx-io-public/paas-monitor:v3.2.4-5-g49d6871 update_test.go
2020/06/23 13:29:53 resolving repository gcr.io/binx-io-public/paas-monitor tag v3.2.4-5-g49d6871 to digest sha256:39af528cdc113845360cefa8ac84c653e7d512e3e2fd2f1506fa5e02ee88bda0
2020/06/23 13:29:53 INFO: updating update_test.go

If you want the image tag back:

$ cru update --image-reference gcr.io/binx-io-public/paas-monitor:v3.2.4-5-g49d6871 ref/update_test.go
2020/06/23 13:31:53 INFO: updating ref/update_test.go

update all to latest and pin to a specific image

If you want to snapshot all image references to the latest version, use --all --resolve-digest:

$ cru update --all --resolve-digest ref/resolve_test.go
2020/06/23 19:49:17 resolving repository mvanholsteijn/paas-monitor tag latest to digest sha256:673545ac2fc55ff8dd8ef734b928aa34e5f498ef5aed2ec4cdfc028efe7585f3
2020/06/23 19:49:17 INFO: updating ref/resolve_test.go

update latest with a specific tag

If you want to update an image reference to the latest version, without knowing the alternate tag:

$ cru update --image-reference gcr.io/binx-io-public/paas-monitor:latest --resolve-tag ref/resolve_test.go
2020/07/18 22:55:32 resolving repository gcr.io/binx-io-public/paas-monitor tag 'latest' to 'v3.2.4-5-g49d6871'
2020/07/18 22:55:32 INFO: updating ref/resolve_test.go

update the digests of all container image references

If you want to update the digests of existing container image references, type:

cru update --all --matching-tag --resolve-digest --verbose ref/resolve_test.go

2023/07/31 13:03:25 INFO: collecting all container references
2023/07/31 13:03:25 INFO: 3 image references found
2023/07/31 13:03:26 resolving repository gcr.io/binx-io-public/paas-monitor Tag latest to Digest sha256:6af765830476b70cdb41d0f05e34a267f0868f56811b31a9a4d8e13c40188063
2023/07/31 13:03:27 resolving repository mvanholsteijn/paas-monitor Tag 3.1.0 to Digest sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3
2023/07/31 13:03:27 resolving repository mvanholsteijn/paas-monitor Tag 3.1.0 to Digest sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3
2023/07/31 13:03:27 INFO: updating reference gcr.io/binx-io-public/paas-monitor:latest to gcr.io/binx-io-public/paas-monitor:latest@sha256:6af765830476b70cdb41d0f05e34a267f0868f56811b31a9a4d8e13c40188063 in ref/resolve_test.go
2023/07/31 13:03:27 INFO: updating reference gcr.io/binx-io-public/paas-monitor:latest to gcr.io/binx-io-public/paas-monitor:latest@sha256:6af765830476b70cdb41d0f05e34a267f0868f56811b31a9a4d8e13c40188063 in ref/resolve_test.go
2023/07/31 13:03:27 INFO: updating reference mvanholsteijn/paas-monitor:3.1.0 to mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 in ref/resolve_test.go
2023/07/31 13:03:27 INFO: updating reference mvanholsteijn/paas-monitor:3.1.0 to mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 in ref/resolve_test.go
2023/07/31 13:03:27 INFO: updating reference mvanholsteijn/paas-monitor:3.1.0 to mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 in ref/resolve_test.go
2023/07/31 13:03:27 INFO: mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 already up-to-date in ref/resolve_test.go
2023/07/31 13:03:27 INFO: mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 already up-to-date in ref/resolve_test.go
2023/07/31 13:03:27 INFO: mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 already up-to-date in ref/resolve_test.go
2023/07/31 13:03:27 INFO: mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 already up-to-date in ref/resolve_test.go
2023/07/31 13:03:27 INFO: mvanholsteijn/paas-monitor:3.1.0@sha256:c0717cab955aff0a3d2f6bb975808ba9708d8385bcf01a18e23ff436f07c1fb3 already up-to-date in ref/resolve_test.go
2023/07/31 13:03:27 INFO: updated a total of 1 files
2023/07/31 13:03:27 INFO: no commit message, skipping commit and push

cru-as-a-service

To run cru as a service, type:

$ cru serve   \
  --repository git@github.com:mvanholsteijn/scratch.git \
  --branch master
2021/11/09 20:30:27 Listening on port 8080

To update references, type:

$ curl -sS -X POST -H 'content-type: application/json' http://localhost:8080  -d '
{
  "image-references": [ "mvanholsteijn/paas-monitor:3.0.1" ],
  "commit-message": "you can do this."
}'

The response will look like this:

{
  "git-url": "git@github.com:mvanholsteijn/scratch.git",
  "files": [
    "/README.md"
  ],
  "commit-sha": "43025b999e3ccc30557543c0cd336696f9073d49"
}

installation

To install you have a number of different options:

• download the binary from https://github.com/binxio/cru/releases
• install using go install github.com/binx/cru@0.9.0
• or use the docker image: gcr.io/binx-io-public/cru:0.9.0

Caveats

• cru is not context-aware: anything that looks like a container image references is updated.
• cru will ignore any references to unqualified official images, like docker:latest or nginx:3. To update the official docker image references, prefix them with docker.io/ or docker.io/library/.
• the time to find the alternate tag is proportional to the number of tags associated with the image.
• the default git commit username and email is cru / cru@binx.io. It is not taken from gitconfig.