rebar3.mk

January 14, 2024 · View on GitHub

This is a tool to help your Erlang projects either use the existing rebar3 that's already installed in your system or build a new one just for a specific project.

Getting Started

Step 1

There are two possible appraoches of step 1:

The more secure method, but less automated method
The more automated method, but less secure method.

Step 1a - Secure approach

This approach requires less trust than the more automated approach because you're manually downloading rebar3.mk and adding it to your repository.

Download The latest rebar3.mk and add it to the root of your Erlang application's directory. Don't forget to add it to git (or source control of your choice first).

curl -o https://raw.githubusercontent.com/choptastic/rebar3.mk/master/rebar3.mk

Once this is finished, add the following rule to your Makefile

include rebar3.mk

Step 1b - Automated/trusting approach

(Pre-note: I recommend looking at the contents of https://rebar3.mk/init.mk first before running this script. That said, it does not actually run a remote script, but instead just appends text to your Makefile.)

Note: This approach trusts the rebar3.mk repository and domain name more, and is therefore less secure (the more you have to trust something, the less secure it is). It is recommended to always verify the code of a script you're about to download and run from the internet.

Run the following to automatically modify your Makefile to add the rebar3.mk rules.

curl -s -L https://rebar3.mk/init.mk > temp.mk && \
echo "9406b0ee0db6589b91d21fc9cf89759e8a7625678bc2874cfba6a67bd287b8fc  temp.mk" | \
sha256sum -c --quiet && cat temp.mk >> Makefile && rm temp.mk

(this little snippet downloads the text to add to your Makefile, verifies its hash, then appends it to your Makefile. This is a little safer because the hash verification can protect you from rebar3.mk getting hijacked)

Step 2 (Updating some necessary Makefile rules)

Update any rebar3 related targets in your Makefile to add the rebar3 dependency.
Update any invocations of rebar3 or ./rebar3 to instead invoke $(REBAR)

For example, change this:
```
compile:
    rebar3 compile
```
To This:
```
compile: rebar3
    $(REBAR) compile
```

Step 3 (Celebrate!)

Now every time you run make compile, it will check for the presence of rebar3, and if it's not found, download and compile it first.

Updating `rebar3.mk`

You can update the version of rebar3.mk that's installed in your app by running:

make update_rebar3_mk

What should I add to my version control system (git/hg/svn/fossil/etc)?

If you used the secure method, then add Makefile and rebar3.mk to your repository.
If you used the automated method, then just add Makefile to your repository.

Author

MIT Licensed