Matrix job support

[samrocketman]

Jervis needs to create matrix jobs from more complicated .jervis.yml files which test multiple things.

[samrocketman]

A Matrix job wiki page has been created for planning this.

A possible way to test env variables from .jervis.yml is to use a bash case statement. Let's say we have the following in our .jervis.yml file.

env:
  global:
    - FOOBAR=foobar
  matrix:
    - FOO=foo BAR=bar
    - FOO=bar BAR=foo

In the Jenkins job there would be a matrix variable (e.g. RANDMATRIXVAR_123) and it would have integer indices for each matrix it should execute (e.g. RANDMATRIXVAR_123="0 1"). Then our generated Jenkins code would look somewhat akin to the following.

#global variables for all matrices
export foobar=foobar
#variables per matrix index
case ${RANDMATRIXVAR_123} in
  0)
    export foo=foo bar=bar
    ;;
  1)
    export foo=bar bar=foo
    ;;
esac

The indices for the case should match the actual groovy array indices from the parsed yaml to simplify matrix filtering. In fact, now that I think of it this method can be used for all matrix build setup; yay! 💃

[samrocketman]

Jenkins supports matrix exclusion and inclusion in a one line expression.

!(rvm == "2.0.0" && gemfile == "Gemfile") && (rvm == "2.0.0")

Will exclude builds that exactly match rvm: 2.0.0 and gemfile: Gemfile but will include only combinations that have rvm: 2.0.0. Apply that matrix inclusion/exclusion string to the following yaml configuration.

language: ruby
rvm:
  - 1.9.2
  - 2.0.0
gemfile:
  - Gemfile
  - gemfiles/rails4.gemfile
  - gemfiles/rails32.gemfile
  - gemfiles/rails31.gemfile

That means only three matrix builds will actually execute. The matrix will build rvm: 2.0.0 against the gemfile: gemfiles/rails4.gemfile, gemfile: gemfiles/rails32.gemfile, and gemfile: gemfiles/rails31.gemfile.

The above one line expression can be more generically expressed as...

!(exclusion) && (inclusion)

[samrocketman]

Let's combine the previous two comments in a solid ruby example.

language: ruby
rvm:
  - 1.9.2 #$rvm index 0
  - 2.0.0 #$rvm index 1
gemfile:
  - Gemfile #$gemfile index 0
  - gemfiles/rails4.gemfile #$gemfile index 1
  - gemfiles/rails32.gemfile #$gemfile index 2
  - gemfiles/rails31.gemfile #$gemfile index 3
matrix:
  exclude:
    - { rvm: 2.0.0, gemfile: Gemfile }
  include:
    - rvm: 2.0.0

Will turn into bash code. Assume that the matrix environment variables are ${rvm} and ${gemfile} respectively.

case ${rvm} in
  0)
    rvm use 1.9.2
    ;;
  1)
    rvm use 2.0.0
    ;;
esac
case ${gemfile}
  0)
    export BUNDLE_GEMFILE="Gemfile"
    ;;
  1)
    export BUNDLE_GEMFILE="gemfiles/rails4.gemfile"
    ;;
  2)
    export BUNDLE_GEMFILE="gemfiles/rails32.gemfile"
    ;;
  3)
    export BUNDLE_GEMFILE="gemfiles/rails31.gemfile"
    ;;
esac

There will be two user-defined axes.

1. Name: rvm; Value: 0 1
2. Name: gemfile; Value: 0 1 2 3

The matrix filter would then look like the following (based on inclusion and exclusion filters).

!((rvm == "1" && gemfile = "0")) && (rvm == "1")

The following matrix will execute: $rvm == "1" and ($gemfile == 1 or $gemfile == 2 or $gemfile == 3).

[samrocketman]

I submitted a matrix plugin feature request to allow build failures in the matrix. This is so I can replicate Travis CI allow_failures configuration option.

[samrocketman]

Partial support was implemented in 4bd3291.

Still need to support:

env:
  global:
    - FOOBAR=foobar
  matrix:
    - FOO=foo BAR=bar
    - FOO=bar BAR=foo

[samrocketman]

Matrix exclusion has been implemented in e4edfa8.

[samrocketman]

Matrix support has been fully implemented today leading up to commit 591f6bb.