Conversions

Parsing CSV files

Ansible offers the community.general.read_csv module to read CSV files. Sometimes you need to convert strings to CSV files instead. For this, the from_csv filter exists.

- name: "Parse CSV from string"
  debug:
    msg: "{{ csv_string | community.general.from_csv }}"
  vars:
    csv_string: |
      foo,bar,baz
      1,2,3
      you,this,then

This produces:

TASK [Parse CSV from string] **************************************************************
ok: [localhost] => {
    "msg": [
        {
            "bar": "2",
            "baz": "3",
            "foo": "1"
        },
        {
            "bar": "this",
            "baz": "then",
            "foo": "you"
        }
    ]
}

The from_csv filter has several keyword arguments to control its behavior:

dialect:

Dialect of the CSV file. Default is excel. Other possible choices are excel-tab and unix. If one of delimiter, skipinitialspace or strict is specified, dialect is ignored.

fieldnames:

A set of column names to use. If not provided, the first line of the CSV is assumed to contain the column names.

delimiter:

Sets the delimiter to use. Default depends on the dialect used.

skipinitialspace:

Set to true to ignore space directly after the delimiter. Default depends on the dialect used (usually false).

strict:

Set to true to error out on invalid CSV input.

Converting to JSON

JC is a CLI tool and Python library which allows to interpret output of various CLI programs as JSON. It is also available as a filter in community.general. This filter needs the jc Python library installed on the controller.

- name: Run 'ls' to list files in /
  command: ls /
  register: result

- name: Parse the ls output
  debug:
    msg: "{{ result.stdout | community.general.jc('ls') }}"

This produces:

TASK [Run 'ls' to list files in /] ********************************************************
changed: [localhost]

TASK [Parse the ls output] ****************************************************************
ok: [localhost] => {
    "msg": [
        {
            "filename": "bin"
        },
        {
            "filename": "boot"
        },
        {
            "filename": "dev"
        },
        {
            "filename": "etc"
        },
        {
            "filename": "home"
        },
        {
            "filename": "lib"
        },
        {
            "filename": "proc"
        },
        {
            "filename": "root"
        },
        {
            "filename": "run"
        },
        {
            "filename": "tmp"
        }
    ]
}