customizing_pipeline_templates.md

Ego Templates

Travel-Agent relays on ego as its template engine to build the pipeline configuration for concourse.

See pipeline example here

Tags

Ego uses tags to embed golang code.

There are 2 tags available:

1. Execution tag <% %>
2. Execution and output tag <%= %>

Execution only tag

Code gets executed but the result will not be included in the pipeline configuration file.

<% if { %>
<% } %>

Execution and output tag

Code gets executed and the output gets included in the pipeline configuration file.

<%= env.Name %> 

Golang and Travel-agent

Conditionals

<% if CONDITION { %>
<% } else { %>
<% } %>

Iterators

<% for _, VAR_NAME := range ARRAY { %>
<% } %>

Travel-agent helpers

Travel-agent allows you to retrive data from the travel-agent.yml config file through helpers.

<%! func ManifestTmpl(w io.Writer, config Config) error %>
<%% import . "github.com/compozed/travel-agent/models" %%>

config.Envs

Retuns list of all the available environments.

env.HasFeature()

Returns features available for an specific environment

<% if env.HasFeature("check_for_existence") { %>

env.Feature()

'<%= env.Feature("grab_value") %>'

Pulls data for an specific environment.

name: <PIPELINE_NAME>
envs:
- name: <ENV_NAME>
  features:
    grab_value: foo