I was able to deploy Dart Comics, my sample Dart application, to Heroku. At this point I have the server-side Dart running properly, but the client-side Dart not so much.
Actually, the Dart code that is in the
publicdirectory of my application is being received just fine by Dartium. The problem is that the Hipster MVC client library is nowhere to be found:
That is not all that surprising considering that the Dart Pub dependency install script has only been run for server-side dependencies—not for my client libraries. Since this is Heroku, I cannot shell into my server an install things. Instead I need a buildpack to get this installed at build time.
As far as I know, it is only possible to run one buildpack at a time on Heroku, so I fork the Dart buildpack to pub install not only the server-side, but also the client-side pub packages. As my first attempt, I try to simply pub install in the public/scripts directory by adding the following to the
#... message "-----> Install client packages" cd $BUILD_DIR/public/scripts #start pub from the /app folder to have correct symlink paths /app/dart-sdk/bin/pub install #...After committing that change to my fork, I configure my app to use this buildpack instead of the official Dart buildpack:
➜ dart-comics git:(master) heroku config:add BUILDPACK_URL=https://github.com/eee-c/heroku-buildpack-dart.git Setting config vars and restarting dart-comics... done, v11 BUILDPACK_URL: https://github.com/eee-c/heroku-buildpack-dart.gitWith that, I am ready to try it out. I do not know how to force deploy, so I make a minor change and push it:
➜ dart-comics git:(master) gp heroku master Counting objects: 11, done. Delta compression using up to 4 threads. Compressing objects: 100% (7/7), done. Writing objects: 100% (7/7), 983 bytes, done. Total 7 (delta 3), reused 0 (delta 0) -----> Heroku receiving push -----> Fetching custom git buildpack... done -----> Dart app detected -----> Installing Dart VM, build: latest -----> Copy Dart binaries to app root -----> Install server packages Resolving dependencies... Dependencies installed! -----> Install client packages Resolving dependencies... Downloading hipster_mvc 0.2.0... Dependencies installed! -----> Discovering process types Procfile declares types -> web -----> Compiled slug size: 6.2MB -----> Launching... done, v12 http://dart-comics.herokuapp.com deployed to Heroku To email@example.com:dart-comics.git a49850f..5529e3b master -> masterNice! That definitely picked up my Hipster MVC client-side package and installed it. Unfortunately that is not quite the end of the story because the Hipster MVC files are still not seen on the server.
After a bit of digging, I find that, although the public/scripts/packages is linked properly:
~/public/scripts $ ls -lh packages hipster_mvc -> /app/tmp/repo.git/.cache/pub-cache/hosted/pub.dartlang.org/hipster_mvc-0.2.0/libThe public/scripts/web/packages directory that really matters is still linked to the build directory:
~/public/scripts $ ls -lh web/packages web/packages -> /tmp/build_2srdmesaavhar/public/scripts/packagesTo fix this, I overwrite the public/scripts/web/packages symlink in the
# ... message "-----> Install client packages" cd $BUILD_DIR/public/scripts #start pub from the /app folder to have correct symlink paths /app/dart-sdk/bin/pub install # still have to brute force web/packages cd $BUILD_DIR/public/scripts/web ln -sf ../packages #...I am unsure if that would work as a general purpose solution, but in my case, I only have the single dependency so this ought to be OK.
And that does the trick. Now when I reload the application, all of the Dart files load, the Hipster MVC libraries included. With that, I can use my Dart browser to load a Dart application backed by a Dart MVC framework. This, in turn, talks to a Dart web server on Heroku that talks to a Dart datastore. That's a whole lot of Dart:
And, in Heroku-style, I do it all with a single git push.