load_var Step

Load the value for a var at runtime from a file, making it available to subsequent steps as a local build var named after the given identifier. Expand each section below for more details and examples.

load_var: identifier (required)

The identifier will be the name of var, available to subsequent steps as a local build var.

Loading a simple value as a var

The following pipeline loads vars from a text file whose contents are used as a version number to put.

jobs:
  - name: loading-vars
    plan:
      - get: examples
      - load_var: version
        file: examples/misc/simple-value.txt
      - put: img
        params:
          version: ((.:version))


resources:
  - name: examples
    type: git
    icon: github
    source:
      uri: https://github.com/concourse/examples.git
  - name: img
    type: mock

simple-value.txt looks like this:

2.6.0

file: file-path (required)

The path to a file whose content shall be read and used as the var's value.

format: json | yaml | yml | trim | raw

The format of the file's content.

If unset, Concourse will try to detect the format from the file extension. If the file format cannot be determined, Concourse will fallback to trim.

If set to json, yaml, or yml, the file content will be parsed accordingly and the resulting structure will be the value of the var.

If set to trim, the var will be set to the content of the file with any trailing and leading whitespace removed.

If set to raw, the var will be set to the content of the file without modification (i.e. with any existing whitespace).

Loading a var with multiple fields

Let's say we have a file with multiple fields, like this yaml file:

first: initial
number: "9000"
hello: HAL

We could pass these values to subsequent steps by loading it into a var with load_var, which will detect that it is in YAML format based on the file extension:

jobs:
  - name: loading-vars
    plan:
      - get: examples
      - load_var: version
        file: examples/pipelines/vars-file.yml
      - put: img
        params:
          version: "((.:version.hello))-((.:version.number))"


resources:
  - name: examples
    type: git
    icon: github
    source:
      uri: https://github.com/concourse/examples.git
  - name: img
    type: mock

If the file vars-file.yml was generated in a task and printed these values, they would be automatically redacted unless reveal: true is set.

reveal: boolean

Default false. If set to true, allow the var's content to be printed in the build output even with secret redaction enabled.