Basic Git integration with Google App Engine
So we at sendapatch.se use Git a lot for the our productions. It's great.
One vital detail you need to know in App Engine development is what’s up there, … y'know, up in the cloud.
The solution is as obvious as it is useful and tedious to write, for your consideration: a script that updates App Engine from the current HEAD and bookmarks it in a branch named
#!/bin/bash # updates appengine from current HEAD and puts tree in uploaded-<version> BASE=. PYTHON=python2.7 APPENGINE=$BASE/google_appengine APP=$BASE/app VERSION="$(grep '^version: ' "$APP/app.yaml" | cut -c 10-)" BRANCH="uploaded-$VERSION" echo "Creating snapshot for $VERSION" >&2 TREE="$(git write-tree)" COMMIT="$(git commit-tree $TREE -p HEAD <<COMMIT Upload $VERSION to Google App Engine COMMIT )" echo "commit $COMMIT" git branch -f "$BRANCH" "$COMMIT" || exit exec "$PYTHON" "$APPENGINE/appcfg.py" update app "$@"
Why do you use the low level git commands here instead of the porcelain commands?
could you have done:
COMMIT="$(git commit -m <<COMMIT
Upload $VERSION to Google App Engine
Is it because you don't want to commit the current index to your current branch? You only want to commit it to a new branch and push it?
Because a mere git commit won't necessarily commit, for example if there are no unstaged changes or otherwise. This script writes the current index and sets a branch to a commit pointing to that tree.