envstache

Command-line tool for rendering Mustache templates using environment variables.

Usage

$ go get github.com/hoisie/mustache
$ go install github.com/tokenshift/envstache

$ echo "Test Value: {{TEST_VAL}}" | TEST_VAL="42" envstache
Test Value: 42

$ export TEST_VALUES="Test Value 1
> Test Value 2
> Test Value 3"
$ echo "{{#TEST_VALUES}}
>* {{.}}
>{{/TEST_VALUES}}" | envstache
* Test Value 1
* Test Value 2
* Test Value 3

envstache can also take key=value parameters on the command line; these will be added (and override) environment variables:

$ export TEST_VALUE="testing"
$ echo "Test Value: {{TEST_VALUE}}" | envstache
Test Value: testing
$ echo "Test Value: {{TEST_VALUE}}" | envstache TEST_VALUE=hello
Test Value: hello

If you need to render structured/nested data, use the --json argument to provide a string of JSON:

$ echo "Value: {{#some}}{{#nested}}{{value}}{{/nested}}{{/some}}" | \
  envstache --json '{"some": {"nested": {"value": "Got Here"}}}'
Value: Got Here

Precedence: Command line args > JSON > environment variables.

Full example:

$ export test_value1="Im an environment variable"
$ export test_value2="So am i"
$ export test_value3="Me too"
$ echo "{{test_value1}}
> {{test_value2}}
> {{test_value3}}" | envstache --json '{"test_value2": 42, test_value3": "Hello from JSON"}' test_value2=command_line 
I'm an environment variable
command_line
Hello from JSON