Is there a way to tell nuGet to install a file, into a project, only if the file is not already in the project?

问题

Is there a way to configure a nuGet package so that a file is installed, inside a project, only if it does not already exist in the project?

Specifically, my nuGet package contains a custom config file. Once installed, the user will make modifications to the file. The problem is that the config file gets replaced when the user installs a new version of my nuGet package -- thus, losing their changes. I want to prevent this.

回答1:

Let's assume that you are using Visual Studio and need to deploy log4net.config if it is missing.

Create the "tools" folder under the folder with your *.nuspec file

Add to the nuspec file:

     <file src="tools/**/*.*" target="\" /> 
  </files>
</package>

It will include the files in the tools folder into the package

place inside the tools folder the file install.ps1 with some code similar to:

param($installPath, $toolsPath, $package, $project)

$log4netInProjectFolder = $project.ProjectItems | Where-Object { $_.Properties.Item("Filename").Value -eq "log4net.config" }

if ($log4netInProjectFolder -eq $null)
{
    Write-Host "File with path $deployTarget doesn't exist, deploying default log4net.config"

    foreach($item in $filesToMove) 
    {
        Write-Host "Moving " $item.Properties.Item("FullPath").Value
        (Get-Interface $project.ProjectItems "EnvDTE.ProjectItems").AddFromFileCopy($item.Properties.Item("FullPath").Value)
        (Get-Interface $item "EnvDTE.ProjectItem").Delete()
    }   
 }
 else
{
    Write-Host "File $deployTarget already exists, preserving existing file."
}

Create the package using (for example):

nuget pack PackageWithMyLogConfig.nuspec -Version 1.0.0

If you want to look inside the generated package, rename it to *.zip. Then you can view what's inside using any archive manager.

回答2:

Probably an old question but here it goes anyway, as I also had this problem:

This can be done by manually updating the packages using the command line as shown in the PowerShell reference:

Update-Package [-Id] <string> [-IgnoreDependencies] [-ProjectName <string>] [-Version <string>] [-Source <string>] [-Safe] [-IncludePrerelease] [-Reinstall] [-FileConflictAction] [-WhatIf]

The parameter you need to use is -FileConflictAction which you must set to Ignore.

Edit: Problem is, this does not work for only one specific file, so you may have to consider renaming the config file included in the package.

来源：https://stackoverflow.com/questions/26917278/is-there-a-way-to-tell-nuget-to-install-a-file-into-a-project-only-if-the-file

标签

nuget

nuget-spec