lein-tools-deps

A leiningen plugin that lets you share tools.deps.alpha deps.edn dependencies with your leiningen project build.

Why use leiningen and deps.edn?

The Clojure 1.9.0 command line tools bring a host of new benefits to the Clojure practitioner. In particular native support for dependencies hosted in git repositories (and not deployed as maven artifacts), faster startup times for project REPLs, and easier ways to script with Clojure and define multi-project projects; all whilst providing a purely declarative data format in the form of deps.edn files.

However at its core deps.edn and the CLI tools are just a simple system that provide better facilities for resolving dependencies and building a java classpath. They actively avoid being a build tool, and consequently can't be used in isolation to build a project, :aot compile it, uberjar it, etc...

Leiningen is the incumbent build tool for Clojure projects. It's well supported, with a thriving plugin ecosystem, and is the default choice in the Clojure world if you need to build an application or deploy a library. It's easy to get started with and is great if you have a pro-forma project; which doesn't need much custom build-scripting.

lein-tools-deps teaches Leiningen to take its :dependencies from your deps.edn files, which means you can get the best of both worlds. You can use clj and deps.edn to take advantage of deps.edn sub-projects, located on the local filesystem (:local/root) and in git repositories (:git/url) or make use of standard maven dependencies (:mvn/version).

lein-tools-deps will let you replace your leiningen :dependencies entirely with those from deps.edn meaning you don't need to repeat yourself. Likewise for deps.edn projects if you need to start :aot compiling, uberjaring, or integrating with a :cljs-build, you now can.

Essentially lein-tools-deps lets Clojure practitioners use both Leiningen and the clj / deps.edn tools together in the same project.

Why not use boot instead?

Boot is arguably a better choice than Leiningen if you need more bespoke build scripting. However Leiningen projects because of their declarative constraints tend to be more uniform and familiar. Leiningen projects are harder to turn into unique snowflakes, which might be better or worse for you.

If you don't need anything fancy (like a combined Clojurescript/Clojure build) and want to just get started quickly, I'd recommend Leiningen over Boot. If you don't need to :aot, or to build your Clojure at all, and your development environment and prefered tools support it go lightweight and just use clj and deps.edn.

If you want to integrate boot with tools.deps you can via @seancorfield's boot-tools-deps.

Why not just use deps.edn?

If you can do this, consider it, and consider not using lein-tools-deps at all. Yes, I'm saying maybe you don't need this project; even if it is pretty good :-)

deps.edn is starting to grow an ecosystem of tools and whilst they're not yet mature, and the landscape is frequently changing, with various contenders many existing tools such as the Clojurescript compiler, and figwheel-main have native support for deps.edn. Additionally there are new tools such as depstar, pack.alpha, katamari that will work with deps.edn and might be able to build that uberjar for you.

See the tools.deps Tools page for a more complete list of available tooling.

lein-tools-deps is for those who need or want to keep a foot in both camps. Perhaps it's suitable as a stop gap solution for an existing leiningen project, or perhaps members of your team are only just getting used to leiningen, and you don't want to confuse them with another tool or workflow.

More Frequently Asked Questions...

Usage

Simply add the following to your plugins and middleware vectors, respectively, in your project.clj:

  :plugins [[lein-tools-deps "0.4.1"]]

  :middleware [lein-tools-deps.plugin/resolve-dependencies-with-deps-edn]

Then set :lein-tools-deps/config to specify which deps.edn files to resolve, we recommend:

:lein-tools-deps/config {:config-files [:install :user :project]}

The keywords :install, :user and :project will be resolved by the plugin. You can also supply your own paths as strings, e.g.

:lein-tools-deps/config {:config-files [:install :user :project "../src/deps.edn"]}

You can now delete your :dependencies vector from project.clj.

Note: With lein-tools-deps 0.3.0-SNAPSHOT and earlier, the config value was a vector and looked like :tools/deps [:install :user :project], as of 0.4.0 it changed to the above map based syntax.

Supported configuration options

:config-files

A vector referencing an ordered collection of deps.edn files that will be used for dependency resolution. Each file should be either a file path string or a special keyword (:install :user or :project). The special :install and :user keys refer to the deps.edn files defined in the installation and user's home .clojure config directories; whilst :project refers to a deps.edn at the root of your leiningen project.

:clojure-executables

A vector of strings identifying possible install locations for the clojure command line tool script. They will be tried in order, with the first match being used. The default is currently set to [/usr/local/bin/clojure]. This is necessary as lein-tools-deps uses the clojure executable to determine some system specific defaults, such as the location of the :install :config-files.

:resolve-aliases

A vector of deps.edn alias names whose :extra-deps, override-deps and :default-deps will be resolved with the same semantics as if they had been used with the -R option to the clj tool.

:classpath-aliases

A vector of deps.edn alias names whose :extra-paths and classpath-overrides will be applied with the same semantics as if they had been used with the -C option to the clj tool.

:aliases

A vector of deps.edn alias names whose values are resolved in the same way as for both :resolve-aliases and classpath-aliases above. Equivalent to the -A option of the clj tool.

Profiles

lein-tools-deps works with Leiningen profiles, allowing you to specify dependencies on a per profile basis. We support the use of any configuration options in Leiningen profiles, which will follow Leiningen's standard meta-merge semantics for each of the configuration options above. Profiles are merged before tools.deps resolution.

E.g.

    :lein-tools-deps/config {:config-files ["foo.edn"]}
    :profiles {:dev {:lein-tools-deps/config ["bar.edn" "baz.edn"]}}

results a logical :config-files value of ["foo.edn" "bar.edn" "baz.edn"] when the :dev profile is used.

Aliases and all other options are resolved in a similar fashion, and support the use of Leiningen's ^:replace/^:displace metadata flags, to control the merge.

One of the benefits of lein-tools-deps is that you can use profiles to group various combinations of :aliases etc under a single profile name.

Prerequisites

You will need the following base dependencies installed:

• Java 8 (recommended)
• Leiningen 2.8.1
• Clojure CLI Tools (1.9.0.341 or above)

Project Status

ALPHA because tools.deps is still .alpha.

PRs & ideas for future development welcome.

Please see the issue tracker

With thanks to

• @HughPowell
• @mfikes
• @seancorfield
• @puredanger
• @atroche
• @marco-m

License

Copyright © 2017 Rick Moynihan

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.