- say goodbye to checkouts
- Hot load source code and resources from libraries (including transitive dependencies).
- No changes to your projects or project.clj
- No monkey business with symlinks
For anything but toy projects, it essential to break up the code into separate libraries.
In the Clojure world this works great, but there's a little problem.
It is a hassle to work simultaneously on a Clojure project and the libraries
it depends on.
Whenever a change is made to a source file of a library, that library has to be built,
installed in a repo, and the main project has to be rebuilt. Only then can
you run your code and check if the change worked or not.
Worse yet, you might have libraries in you application that depend on the library you changed, so you need to rebuild those as well before rebuilding the application.
This goes counter to the try-it-out-now culture so central to the cult of the REPL.
It is no wonder that some people opt to cowboy code, refraining from properly partitioning their code into separately versioned libraries.
Leiningen acknowledges the problem and offers a partial solution called checkouts. It works well, but it can be bothersome and error-prone.
Add some Hotsauce!
Hotsauce is built on the same idea as checkouts, but removes most of the hassle.
Let's say you have some projects that depend on libraries x and y, and that the source code of these has been checked out to your local filesystem.
-
Register the local path with Hotsauce:
lein hotsauce path-to-lib-x path-to-lib-y -
Make the libraries hot by typing
lein hotsauce hot x y -
Make sure Hotsauce is active by typing
lein hotsauce on(You can always turn Hotsauce off again with
lein hotsauce off)
Leiningen will now do all its normal tasks on any project as, fetching source and resources related to project x and y from the local filesystem.
Suddenly the local source is hot!
Start the main projects with your favourite IDE or just lein repl,
and you can edit and reload source files from x and y to your
heart's content. You don't even have to worry if the version
numbers correspond to what the main projects declare.
When you are done and sure that it all works (yes, lein test
also respects hot projects), just turn Hotsauce off
again, and bump version numbers, check in etc. as you would do normally.
I recommend making Hotsauce available for all of your projects.
If you have no ~/.lein/profiles.clj file, you could just create one
and give it this content:
{:user {:plugins [[hotsauce "0.1.6-SNAPSHOT"]] }}If you already have a ~/.lein/profiles.clj file, you will
need to add[hotsauce "0.1.6-SNAPSHOT"]to the:pluginsvector.
Using Hotsauce can be an individual decision that impacts nobody else.
But if you want to make life extra easy for team members, you might want to include the Hotsauce plugin in the project.clj of your main projects, so it will be automatically available for everybody.
Just add[hotsauce "0.1.6-SNAPSHOT"]to the:pluginsvector insidedefprojectinproject.clj
Actually, what you have read so far on this page should be enough to get you going.
However, here's a bit more:
Hotsauce is spicey, but still in beta.
I would expect some issues could arise with profiles and with ClojureScript.
In my experience, when I use figwheel for web development, I often have to hard reload a ClojureScript application in Chrome after I change Hotsauce on/off or dependencies hot/cold.
This seems to be a problem with figwheel, as the js-code is being correctly generated.
- You name could go here
- or maybe here...
Pull requests are welcome.
Thanks to Thomas Engelschmidt for a good conversation about various development pain points, build tooling and the JVM CLASSPATH. Ultimately that led me to reshape some tooling ideas I had and to put together with this simple plugin.
Thanks to Mikkel Gravgaard for early comments.
Copyright © 2017 Mads Olsen
Distributed under the Eclipse Public License version 1.0