fix: include submodule bare repos in docker build context

[focusaurus]

Impact: minor
Type: bugfix|chore

Issue

OK this one is a pretty long chain to understand, but here goes. If you bundle your custom reaction plugins by adding them as git submodules, and one of your plugins depends on a package directly from github, it seems to cause docker builds to fail during the npm install. For some reason, in this scenario npm wants to access the submodule's gitdir (no idea what for). Given the globs in the .dockerignore as is, that directory does not exist in the docker container during the build.

Solution

Add an exclusion line to .dockerignore so the necessary directories are part of the docker build context.

Breaking changes

None

Testing

cd $(mktemp -d /tmp/submod-XXX)
git init repro
cat <<EOF > repro/package.json
{
  "name": "repro",
  "version": "1.0.0",
  "dependencies": {
    "epimetheus": "github:reactioncommerce/node-epimetheus#baseurl-undefined"
  }
}
EOF
cd repro
git add .
git commit -m "1"
cd ..
git clone https://github.com/reactioncommerce/reaction.git
cd reaction
git submodule add -f "${PWD}/../repro" imports/plugins/custom/repro

• copy your main reaction .env into this test reaction directory
• stop any other reaction containers that may be running

docker-compose build
docker run --rm -it reaction_reaction bash

OK now you're in the container which is kind of like how it is in some CI environments.

cd imports/plugins/custom/repro
npm i

You'll get this error:

npm ERR! Error while executing:
npm ERR! /usr/bin/git ls-remote -h -t ssh://git@github.com/reactioncommerce/node-epimetheus.git
npm ERR! 
npm ERR! fatal: Not a git repository: ../../../../.git/modules/imports/plugins/custom/repro
npm ERR! 
npm ERR! exited with error code: 128

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/node/.npm/_logs/2019-04-12T02_37_02_115Z-debug.log

[aldeed]

I'd add a comment line above it with text similar to your explanation in this PR description. I know any of us looking at this in a year will probably think that line wrong and not remember why it's there.

But other than that, the change seems specific and safe. I didn't test it.

[focusaurus]

Good idea. Comment added.

[rosshadden]

This looks okay to me, not knowing too much about it other than what you said and my own light research. It took a while to run everything, but I was able to reproduce both the problem and your fix.