psyml

YAML PowerShell module

This PowerShell module is a wrapper on top of YamlDotNet that serializes and deserializes PowerShell objects to and from YAML.
It is heavily inspired by standard ConvertFrom-Json and ConvertTo-Json implementations.

The main idea of psyml was to create a binary PowerShell YAML module that will be idempotent when converting back and forth objects and YAML strings and would not lose original types.
If some value is wrapped in single or double quotes in YAML string it is still a string after serialization and stays to be the string after deserialization.

As the examples are better than elaborates, this is the desired behavior:

PS /> $yaml = 'key: "True"'
PS /> $object = ConvertFrom-Yaml $yaml
PS /> $object.key.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     String                                   System.Object

PS /> $object | ConvertTo-Yaml
key: "True"

and this is not:

PS /> $yaml = 'key: "True"'
PS /> $object = ConvertFrom-Yaml $yaml
PS /> $object.key.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     Boolean                                  System.ValueType

PS /> $object | ConvertTo-Yaml
key: true

In case something is not handled in this manner please use Issues page

Installation

PowerShell Gallery

Run the following command in a PowerShell session to install the rollup module for psyml cmdlets:

Install-Module -Name psyml -Scope CurrentUser

This module runs on Windows PowerShell with .NET Framework 4.8 or greater, or PowerShell Core.

If you have an earlier version of the psyml modules installed from the PowerShell Gallery and would like to update to the latest version, run the following commands in a PowerShell session:

Update-Module -Name psyml -Scope CurrentUser

Update-Module installs the new version side-by-side with previous versions. It does not uninstall the previous versions.

Usage

ConvertTo-Yaml

Convert object to YAML

To convert object to YAML use ConvertTo-Yaml cmdlet:

PS /> $object = @{
    property = 'value1'
    array = @(
        1,
        2,
        3
    )
    nested = @{
        bool = $true
        string = 'True'
    }
}
PS /> ConvertTo-Yaml $object
property: value1
nested:
  bool: true
  string: "True"
array:
- 1
- 2
- 3

Convert object to JSON compatible YAML (valid JSON)

To convert object to YAML use ConvertTo-Yaml cmdlet with -JsonCompatible parameter:

PS /> $object = @{
    property = 'value1'
    array = @(
        1,
        2,
        3
    )
    nested = @{
        bool = $true
        string = 'True'
    }
}
PS /> ConvertTo-Yaml $object -JsonCompatible
{"property": "value1", "nested": {"bool": true, "string": "True"}, "array": [1, 2, 3]}

ConvertFrom-Yaml

Convert YAML to object

To convert YAML to object use ConvertFrom-Yaml cmdlet:

PS /> $yaml = @"
property: value1
nested:
  bool: true
  string: "True"
array:
- 1
- 2
- 3
"@
PS /> $object = ConvertFrom-Yaml $yaml
PS /> $object

property nested                    array
-------- ------                    -----
value1   @{bool=True; string=True} {1, 2, 3}

PS /> $object.GetType()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     False    PSCustomObject                           System.Object

To change output type to Hash Table use -AsHashtable parameter:

PS /> $object = ConvertFrom-Yaml $yaml -AsHashtable
PS /> $object.gettype()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     Hashtable                                System.Object

To change output type to Ordered Dictionary use -AsOrderedDictionary parameter:

PS /> $object = ConvertFrom-Yaml $yaml -AsOrderedDictionary
PS /> $object.gettype()

IsPublic IsSerial Name                                     BaseType
-------- -------- ----                                     --------
True     True     OrderedDictionary                        System.Object

Reporting Issues and Feedback

To report issue, bug or feature request please use the Issues page