There is a new building automation tool in the neighborhood named Earthly. Its intention is to simplify CI pipelines. Nothing like an image to explain it better:
I would describe it as a docker multistage build with batteries. It actually has a Docker-like syntax.
These are some features right from their repo:
🐳 Build anything via containers - build container images or standalone artifacts (eg binaries, packages, arbitrary files)
🛠 Programming language agnostic - allows use of language-specific build tooling
♻️ Reproducible builds - does not depend on user’s local installation. Runs the same locally, as in CI
⛓ Parallelism that just works - builds in parallel without special considerations the user has to make
🏠 Mono-repo friendly - ability to split the build definitions across a vast directory hierarchy
🏘 Multi-repo friendly - ability to import builds or artifacts from other repositories
Building something with Earthly
Some days ago while taking a look at Quarkus I found Funqy, part of Quarkus’s serverless strategy that aims to provide a portable Java API to write functions deployable to various FaaS environments like AWS Lambda, Azure Functions, Knative, and Knative Events (Cloud Events). So I decided to see how easy would it be to build a simple “Hello World” with Funqy and Earthly.
I’m not going to focus on the Funqy part since I simply followed their guide. I wanted to know how complicated it would be to define a build.earth file that allowed me to test and build a native quarkus application. This was the result:
FROM quay.io/quarkus/centos-quarkus-maven:20.1.0-java11
WORKDIR /java-example
deps:
COPY pom.xml ./
RUN mvn -B de.qaware.maven:go-offline-maven-plugin:1.2.5:resolve-dependencies
SAVE IMAGE
build:
FROM +deps
COPY src src
RUN mvn -Pnative clean package
SAVE ARTIFACT target/ /target AS LOCAL target
With that file, I am creating a reproducible build that will create a target folder with my artifacts.
As said before, it is very similar to Dockerfile syntax. Apart from just a few new intuitive commands, if you know Docker you will get comfortable with Earthly really fast.
Describing build.earth
base
This section initializes the build environment, it is like a base for all other steps, it applies to all “targets”.
(1) Base Docker image
(2) Setting working directory
(1) FROM quay.io/quarkus/centos-quarkus-maven:20.1.0-java11
(2) WORKDIR /java-example
deps
This section gathers all my project’s dependencies.
(3) Target’s name
(4) Copy the pom.xml to allow earthly to create a layer/cache of the dependencies of my application.
(5) Runs maven and download all my application dependencies.
(6) Saves this container as an image. This allows the following steps/targets to use all the hard work done by these commands.
(3) deps:
(4) COPY pom.xml ./
(5) RUN mvn -B de.qaware.maven:go-offline-maven-plugin:1.2.5:resolve-dependencies
(6) SAVE IMAGE
build
This section actually builds my artifact.
(7) Target’s name
(8) Defines that this target is built from deps target. There is a dependency.
(9) Copy all my source code into the container.
(10) Maven command to execute all my tests and build my artifact.
(11) Saves output into my machine on a target folder.
(7) build:
(8) FROM +deps
(9) COPY src src
(10) RUN mvn -Pnative clean package
(11) SAVE ARTIFACT target/ /target AS LOCAL target
Of course, this is a toy example. You can have earthly files way more complicated (even multi-repo projects). It was also really easy to integrate it into Github Actions. This is the repo for anyone who might want to take a deeper look Earthly Repository.