abpframework/abp · error · CliUsageException

Could not find a class derived from AbpModule in the project

Error message

Could not find a class derived from AbpModule in the project {projectFile}

What it means

After installing the NuGet package, ProjectNugetPackageAdder uses ModuleClassFinder.Find(projectFile, "AbpModule") to locate the dependency-injection root. If zero classes inheriting AbpModule exist in the project, the [DependsOn] cannot be wired and the CLI throws a CliUsageException naming the project file.

Source

Thrown at framework/src/Volo.Abp.Cli.Core/Volo/Abp/Cli/ProjectModification/ProjectNugetPackageAdder.cs:274

        using (DirectoryHelper.ChangeCurrentDirectory(Path.GetDirectoryName(projectFile)))
        {
            Logger.LogInformation(
                $"Installing '{package.Name}' package to the project '{Path.GetFileNameWithoutExtension(projectFile)}'...");

            if (useDotnetCliToInstall)
            {
                await AddUsingDotnetCli(package, version);
            }
            else
            {
                await AddToCsprojManuallyAsync(projectFile, package, version);
            }

            var moduleFiles = ModuleClassFinder.Find(projectFile, "AbpModule");
            if (moduleFiles.Count == 0)
            {
                throw new CliUsageException(
                    $"Could not find a class derived from AbpModule in the project {projectFile}");
            }

            if (moduleFiles.Count > 1)
            {
                throw new CliUsageException(
                    $"There are multiple classes derived from AbpModule in the project {projectFile}: " +
                    moduleFiles.JoinAsString(", "));
            }

            ModuleClassDependcyAdder.Add(moduleFiles.First(), package.ModuleClass);
        }

        if (useDotnetCliToInstall && (package.Target == NuGetPackageTarget.Blazor ||
                                      package.Target == NuGetPackageTarget.BlazorServer ||
                                      package.Target == NuGetPackageTarget.BlazorWebAssembly))
        {
            try

View on GitHub (pinned to 7ed43b1931)

Solutions

1. Add a module class to the target project: 'public class MyProjectModule : AbpModule { }' in a file inside the project.
2. Re-target the command at the project that owns the relevant module class via --project.
3. If installing into a class library is intentional, add the [DependsOn] manually and the package reference via 'dotnet add package'.

Example fix

// before: project has no AbpModule-derived class
// after: add Module.cs
public class MyLibraryModule : AbpModule
{
    public override void ConfigureServices(ServiceConfigurationContext context) { }
}

var modules = ModuleClassFinder.Find(projectFile, "AbpModule");
if (modules.Count == 0)
{ Console.Error.WriteLine($"{projectFile} has no AbpModule-derived class."); return; }

static bool HasSingleModuleClass(string projectFile) =>
    ModuleClassFinder.Find(projectFile, "AbpModule").Count == 1;

When it happens

Trigger: Adding a module package to a non-module project (class library without an AbpModule-derived class), or to a project whose module class is in a different assembly. ModuleClassFinder scans the project's compiled source for ': AbpModule' inheritance and finds none.

Common situations: Targeting a plain class library, a test project, or an infrastructure project that intentionally has no module class; module class declared in a referenced assembly, not the current project; first-time setup where the host module has not been created yet.

Related errors

• There are multiple classes derived from AbpModule in the pro
• "public class" declaration not found!
• Couldn't find any project/solution.
• '{packageName}' nuget package could not be found!
• Package is not found or downloadable!

AI-assisted analysis of abpframework/abp@7ed43b1931 (2026-08-13). Data as JSON: /api/errors/bbe11ed7a1339c99. Report an issue: GitHub.