what is the conventional way of providing config information to a custom Powershell cmdlet

Given that custom PS cmdlets are assemblies I can't provide them config information via the normal 开发者_如何学PythonApp.config route. What is the conventional way of providing config info to a custom cmdlet?

PowerShell is a shell. The normal way of passing information between parts of the shell are shell variables. For powershell that would look like:

$global:MyComponent_MySetting = '12'
# i.e. 
$PSDefaultParameterValues
$ErrorActionPreference

If settings is expected to be inherited across processes boundaries the convention is to use environment variables. I extend this to settings that cross C# / PowerShell boundary. A couple of examples:

$env:PATH
$env:PSModulePath

If you think this is an anti-pattern for .NET you might want to reconsider. This is the norm for PAAS hosted apps, and is going to be the new default for ASP.NET running on server-optimized CLR (ASP.NET v5).

See https://github.com/JabbR/JabbRv2/blob/dev/src/JabbR/Startup.cs#L21
Note: at time of writing I'm linking to .AddEnvironmentVariables()

I've revisited this question a few times, including asking it myself. I wanted to put a stake in the ground to say PowerShell stuff doesn't work well with <appSettings>. IMO it is much better to embrace the shell aspect of PS over the .NET aspect in this regards.

If you need complex configuration take a JSON string. POSH v3+ has ConvertFrom-JSON built-in. If everything in your process uses the same complex configuration put it in a .json file and point to that file from an environment variable.

If a single file doesn't suffice there are well established solutions like the PATH pattern, GIT .gitignore resolution, or ASP.NET web.config resolution (which I won't repeat here).

Normally i would suggest just using parameters for passing data.

Get-MyData -connectionstring $connectionString -table Test ...

When that is not practical (too many parameters, etc..), then you can always provide the path to a configuration file by a parameter:

Get-MyData -Config .\My.config

You can then read the specified configuration file from inside the cmdlet.

This allows users of the cmdlet to define their own configuration files to use.