I have a solution with multiple projects in it (~400). A lot of them are using newtonsoft.json library. Some of them are using different version of the library. In a host project for web app, there is no direct reference to newtonsoft.json. Also, I believe, there are dependencies to packages that depend on newtonsoft.json. However, in bin folder of that project I began getting newtonsoft.json 9.0 instead of newtonsoft.json 11.0 as it used to be. And it causes load exception in runtime due to invalid version. If I include direct reference to newtonsoft.json 11.0, it still puts version 9.0 in the bin folder even if I clear all bin,obj folders. I use PackageReference for managing dependencies, and everything is in .net 4.6.1; I use binding redirects to resolve issues with different versions of the same library.

My question is if there is a way to diagnose how particular dll of package ref appears in bin folder? I would like to see some sort of comprehensive trace of dependency resolution so that I can fix it without using "trial and error" approach.

CodePudding user response：

You can try MSBuild Binary and Structured Log Viewer (https://msbuildlog.com/)

• build the project from command line with msbuild -bl - you will get msbuild.binlog
• open the binlog with the log viewer and use the dll name as a search term
• inspect all records related to the dll and backtrack a place (project and msbuild' target) where the wrong file version is taken.

CodePudding user response：

With PackageReference, NuGet will write a file named project.assets.json in the project's obj folder. This file is used by the rest of the build to determine what files from packages should be included in the build, but it also contains a list of all the packages that were selected, what version was selected, and what dependencies each package has (package id and version). This is the closest thing to dependency resolving debugging that NuGet has.

In the file, search for "Newtonsoft.Json/, and you should find which version of Newtonsoft.Json that NuGet selected. Remove the / and replace it with ", and you can find all the packages that have dependencies on Newtonsoft.Josn. Search for newtonsoft.json.dll to find all the packages that ship that dll in its package (sometimes package authors perfer to ship multiple dlls in their package, rather than adding dependencies, which prevents NuGet from being able to version selection.

If there are multiple packages with which contain a dll with the same filename, NuGet will tell MSBuild about all of them, and it's up to MSBuild to select which one to use (pass to the compiler and copy to the bin/publish directory). As @Serg wrote in their answer, you can use binlogs (with the -bl argument on any MSBuild command, including dotnet restore or dotnet build). NuGet's inner workings are not output to MSBuild, so when your package graph has multiple packages that list Newtonsoft.Json as a dependency, it won't tell you why NuGet chose a specific version, but binlogs are very useful at debugging other build related issues.