coordinate-resolution.md

CDep coordinate resolution

A CDep coordinate uniquely identifies a package. It also contains the information needed to reconstruct a URL to the package's manifest. Here's an example:

com.github.jomof:sqlite:3.16.2-rev51

There are multiple coordinate forms that are used to solve different problems.

Simple form

The simplest coordinate form looks like this:

com.github.jomof:sqlite:3.16.2-rev51

During resolution, CDep decomposes this into pieces.

domain = github.com
user = jomof
artifact = sqlite
version = 3.16.2-rev51

CDep then recomposes these pieces into a URL:

https://github.com/jomof/sqlite/releases/download/3.16.2-rev53/cdep-manifest.yml

The purpose of the simple form of coordinate is just to be able to host the source and releases for a single CDep package.

Compound form

Sometimes you want a family of packages under a single umbrella repo. Coordinates of this form look like this:

com.github.jomof:firebase/admob:2.1.3-rev22
com.github.jomof:firebase/analytics:2.1.3-rev22

These are decomposed in a manner similar to the simple form. The single difference is that the artifact family name is extracted:

domain = github.com
user = jomof
family = firebase
artifact = admob
version = 2.1.3-rev22

Artifact family name is then used to recompose the URL by adding a suffix to the CDep manifest file name.

https://github.com/jomof/firebase/releases/download/2.1.3-rev23/cdep-manifest-admob.yml

Multipackage form

Sometimes you want to use a single Github repo to hold multiple unrelated packages. In this case, you use the multi package form:

com.github.jomof.cdep:boost:1.0.63

The difference is that the group name has four segments rather than three. The final segment is the name of Github repo for the given user. CDep transforms this into a manifest URL similar to this one:

https://github.com/jomof/cdep/releases/download/boost@1.0.63/cdep-manifest.yml

The URL form actually needs to '@' to be escaped. So the true URL is like this:

https://github.com/jomof/cdep/releases/download/boost%401.0.63/cdep-manifest.yml

However, when you create the new Github release to hold this package you should create it with the @ symbol (like boost@1.0.63).

Multipackage form also supports compound packages. These have a coordinate like this:

com.github.jomof.cdep:firebase/admob:2.1.3-rev22