[SOLVED] Is there any way to using hadolint for multiple dockerfiles?

Issue

Hadolint is an awesome tool for linting Dockerfiles. I am trying to integrated to my CI but I am dealing with for run over multiple Dockerfiles. Does someone know how the syntax look like? Here is how my dirs appears to:

dir1/Dockerfile
dir2/Dockerfile
dir3/foo/Dockerfile

in gitlab-ci

  stage: hadolint
  image: hadolint/hadolint:latest-debian
  script:
  - mkdir -p reports
  - |
   hadolint dir1/Dockerfile > reports/dir1.json \
   hadolint dir2/Dockerfile > reports/dir2.json \
   hadolint dir3/foo/Dockerfile > reports/dir3.json 

But the sample above is now working.

Solution

If you want to keep all reports separated (one per top-level directory), you may want to rely on some shell snippet?

I mean something like:

- |
  find . -name Dockerfile -exec \
    sh -c 'src=${1#./} && { set -x && hadolint "$1"; } | tee -a "reports/${src%%/*}.txt"' sh "{}" \;

Explanation:

• find . -name Dockerfile loops over all Dockerfiles in the current directory;
• -exec sh -c '…' runs a subshell for each Dockerfile, setting:
  • $0 = "sh" (dummy value)
  • $1 = "{}" (the full, relative path of the Dockerfile), "{}" and \; being directly related to the find … -exec pattern;
• src=${1#./} trims the path, replacing ./dir1/Dockerfile with dir1/Dockerfile
• ${src%%/*} extracts the top-level directory name (dir1/Dockerfile → dir1)
• and | tee -a … copies the output, appending hadolint's output to the top-level directory report file, for each parsed Dockerfile (while > … should be avoided here for obvious reasons, if you have several Dockerfiles in a single top-level directory).
• I have replaced the .json extension with .txt as hadolint does not seem to output JSON data.

Answered By - ErikMD