gomplate

README

Read the docs at gomplate.hairyhenderson.ca.

gomplate is a template renderer which supports a growing list of datasources, such as: JSON (including EJSON - encrypted JSON), YAML, AWS EC2 metadata, BoltDB, Hashicorp Consul and Hashicorp Vault secrets.

Here are some hands-on examples of how gomplate works:

$ # at its most basic, gomplate can be used with environment variables...
$ echo 'Hello, {{ .Env.USER }}' | gomplate
Hello, hairyhenderson

$ # but that's kind of boring. gomplate has tons of functions to do useful stuff, too
$ gomplate -i 'the answer is: {{ mul 6 7 }}'
the answer is: 42

$ # and, since gomplate uses Go's templating syntax, you can do fun things like:
$ gomplate -i '{{ range seq 5 1 }}{{ . }} {{ if eq . 1 }}{{ "blastoff" | toUpper }}{{ end }}{{ end }}'
5 4 3 2 1 BLASTOFF

$ # the real fun comes when you use datasources!
$ cat ./config.yaml
foo:
  bar:
    baz: qux
$ gomplate -d config=./config.yaml -i 'the value we want is: {{ (datasource "config").foo.bar.baz }}'
the value we want is: qux

$ # datasources are defined by URLs, and gomplate is not limited to just file-based datasources:
$ gomplate -d ip=https://ipinfo.io -i 'country code: {{ (ds "ip").country }}'
country code: CA

$ # standard input can be used as a datasource too:
$ echo '{"cities":["London", "Johannesburg", "Windhoek"]}' | gomplate -d city=stdin:///in.json -i '{{ range (ds "city").cities }}{{.}}, {{end}}'
London, Johannesburg, Windhoek, 

$ # and here's something a little more complicated:
$ export CITIES='city: [London, Johannesburg, Windhoek]'
$ cat in.tmpl
{{ range $i, $city := (ds "cities").city -}}
{{ add 1 $i }}: {{ include "weather" (print $city "?0") }}
{{ end }}
$ gomplate -d 'cities=env:///CITIES?type=application/yaml' -d 'weather=https://wttr.in/?0' -H 'weather=User-Agent: curl' -f in.tmpl
1: Weather report: London

    \  /       Partly cloudy
  _ /"".-.     4-7 °C
    \_(   ).   ↑ 20 km/h
    /(___(__)  10 km
               0.0 mm

2: Weather report: Johannesburg

    \  /       Partly cloudy
  _ /"".-.     15 °C
    \_(   ).   ↘ 0 km/h
    /(___(__)  10 km
               2.2 mm

3: Weather report: Windhoek

    \  /       Partly cloudy
  _ /"".-.     20 °C
    \_(   ).   ↑ 6 km/h
    /(___(__)  20 km
               0.0 mm

Read the documentation at gomplate.hairyhenderson.ca!

Please report any bugs found in the issue tracker.

License

The MIT License

Copyright (c) 2016-2019 Dave Henderson

Documentation

Index

• Variables
• func Funcs(d *data.Data) template.FuncMap
• func RunTemplates(o *Config) error
• type Config
  • func (o *Config) String() string
• type MetricsType

Variables

var Stdout io.WriteCloser = os.Stdout

Stdout allows overriding the writer to use when templates are written to stdout ("-").

Functions

func Funcs

func Funcs(d *data.Data) template.FuncMap

Funcs - The function mappings are defined here!

func RunTemplates

func RunTemplates(o *Config) error

RunTemplates - run all gomplate templates specified by the given configuration

Types

type Config

type Config struct {
	Input       string
	InputFiles  []string
	InputDir    string
	ExcludeGlob []string
	OutputFiles []string
	OutputDir   string
	OutMode     string

	DataSources       []string
	DataSourceHeaders []string
	Contexts          []string

	LDelim string
	RDelim string

	Templates []string
}

Config - values necessary for rendering templates with gomplate. Mainly for use by the CLI

func (*Config) String

func (o *Config) String() string

nolint: gocyclo

type MetricsType

type MetricsType struct {
	TemplatesGathered   int
	TemplatesProcessed  int
	Errors              int
	GatherDuration      time.Duration            // time it took to gather templates
	TotalRenderDuration time.Duration            // time it took to render all templates
	RenderDuration      map[string]time.Duration // times for rendering each template
}

MetricsType - Warning: experimental! This may change in breaking ways without warning. This is not subject to any semantic versioning guarantees!

var Metrics *MetricsType

Metrics tracks interesting basic metrics around gomplate executions. Warning: experimental! This may change in breaking ways without warning. This is not subject to any semantic versioning guarantees!