parcel

Simple go template renderer for nomad and other generic groups of templates (i.e. a light-weight Helm for purely templating).

Command usage

pull

Pull a parcel given the git source URI

parcel pull [options] [SOURCE]

-f --force # (optional) force pull parcel

Examples:

# pull from remote repository
parcel pull git::ssh://git@github.com/bbckr/parcel//example

# pull from local repository
parcel pull git::file://${PROJECT_ROOT}/.git//example

# pull from repository ref
parcel pull git::ssh://git@github.com/bbckr/parcel//example?ref=${GIT_REF}

render

Render template output for a parcel given the parcel identifiers. The parcel must be pulled before it can be referenced.

parcel render [options] [OWNER] [NAME] [VERSION]
-v --values # (optional) path to values yaml file
-o --output # directory to output rendered files (default: .)

Examples:

# render to output directory
parcel render -o .output bbckr example 1.0.0

# override default values
parcel render -v myvalues.yaml bbckr example 1.0.0

Documentation

Parcel structure

Each parcel requires the following directory structure:

folder_name
|_ static/ # place static files to reference in templates here
|_ templates/ # place all your templates here
...|_ job_1.hcl # go template, any name/ext
...|_ job_2.hcl # go template, any name/ext
|_ values.yaml # default values to feed parcel templates
|_ manifest.yaml # parcel manifest

Referencing values in templates

Parcel uses basic Go templating with no added helper functions.

For a full example of how the values.yaml should look and how to reference the values and other injected variables in a template, checkout this example.

For quick reference:

# templates/sample-job.hcl
job "sample-jon" {
    group "sample-group" {
        task "sample-task" {
            config {
                image = "{{ .Values.image.name }}:{{ .Values.image.tag }}"
            }
        }
    }
}

# values.yaml
image:
  name: nginx
  tag: latest

Output:

job "sample-jon" {
    group "sample-group" {
        task "sample-task" {
            config {
                image = "nginx:latest"
            }
        }
    }
}

Template Variables

• .Meta.name Parcel name, taken from manifest
• .Meta.owner Parcel owner, taken from manifest
• .Meta.version Parcel version, taken from manifest
• .Values.* Merged values from default Parcel values and values passed during render
• .Static.path Path to static directory to reference static resources in templates

Template Functions

Uses Go template as a base and adds the following functions:

• toJSON Marshal to JSON string
• replace An alias for strings.Replace
• replaceAll An alias for strings.ReplaceAll
• quote Surround with double quotation marks
• b64encode Base64 encode string
• b64decode Base64 decode string