Code generation failed with: NSTaskTerminationReason(rawValue: 1)

[0xifarouk]

I am getting this error when running the generate-grpc-code-from-protos plugin:

error: Code generation failed with: NSTaskTerminationReason(rawValue: 1):1.
        Executable: /opt/homebrew/bin/protoc
        Arguments: --plugin=protoc-gen-grpc-swift=/Users/farouk/Downloads/gRPC-Demo/.build/arm64-apple-macosx/debug/protoc-gen-grpc-swift-2-tool --grpc-swift_out=/Users/farouk/Downloads/gRPC-Demo/.build/plugins/generate-grpc-code-from-protos/outputs/ --grpc-swift_opt=Visibility=Internal --grpc-swift_opt=Server=true --grpc-swift_opt=Client=true --grpc-swift_opt=FileNaming=FullPath --grpc-swift_opt=UseAccessLevelOnImports=false
        protoc error output:
        Missing input file.

Here is the Package.swift file for the package:

// swift-tools-version: 6.1
// The swift-tools-version declares the minimum version of Swift required to build this package.

import PackageDescription

let package = Package(
  name: "gRPC-Demo",
  platforms: [.macOS(.v15)],
  products: [
    .library(name: "gRPC-Demo", targets: ["gRPC-Demo"]),
  ],
  dependencies: [
    .package(url: "https://github.com/grpc/grpc-swift-2.git", from: "2.0.0"),
    .package(url: "https://github.com/grpc/grpc-swift-protobuf.git", from: "2.0.0"),
    .package(url: "https://github.com/grpc/grpc-swift-nio-transport.git", from: "2.0.0"),
  ],
  targets: [
    .target(
      name: "gRPC-Demo",
      dependencies: [
        .product(name: "GRPCCore", package: "grpc-swift-2"),
        .product(name: "GRPCNIOTransportHTTP2", package: "grpc-swift-nio-transport"),
        .product(name: "GRPCProtobuf", package: "grpc-swift-protobuf"),
      ],
      plugins: [
        .plugin(name: "GRPCProtobufGenerator", package: "grpc-swift-protobuf")
      ]
    ),
  ]
)

grpc-swift-proto-generator-config.json:

{
  "generate": {
    "clients": true,
    "servers": true,
    "messages": true
  },
  "protoc": {
    "executablePath": "/opt/homebrew/bin/protoc"
  }
}

The .proto file:

syntax = "proto3";
package helloworld;

// The greeting service definition.
service Greeter {
  // Sends a greeting
  rpc SayHello (HelloRequest) returns (HelloReply) {}
}

// The request message containing the user's name.
message HelloRequest {
  string name = 1;
}

// The response message containing the greetings
message HelloReply {
  string message = 1;
}

Finally here is the folder structure for the SPM:

What am I doing wrong? Nothing is being generated, I even tried to run the hello-world example in the demo and it's failing with the same error!

[rnro]

Hi! I'm sorry you're hitting this problem, I'm continuing to look into this but my first thought is that you're doing this in the Downloads folder which I think can sometimes require special permissions to access, maybe try doing it elsewhere on disk just as a low-cost test?

[rnro]

I haven't been able to reproduce your issue in my Downloads folder, but our permissions might differ. You're showing screenshots of Xcode but mention .build in your error comment - can you give more information on how you're invoking the build (e.g. Xcode UI or swift build)?

[0xifarouk]

Hi! I'm sorry you're hitting this problem, I'm continuing to look into this but my first thought is that you're doing this in the Downloads folder which I think can sometimes require special permissions to access, maybe try doing it elsewhere on disk just as a low-cost test?

Sorry for the late reply, I tried in the ~/Developer directory but I got the same issue.

error: Code generation failed with: NSTaskTerminationReason(rawValue: 1):1.
        Executable: /opt/homebrew/bin/protoc
        Arguments: --plugin=protoc-gen-grpc-swift=/Users/farouk/Developer/gRPC-Demo/.build/arm64-apple-macosx/debug/protoc-gen-grpc-swift-2-tool --grpc-swift_out=/Users/farouk/Developer/gRPC-Demo/.build/plugins/generate-grpc-code-from-protos/outputs/ --grpc-swift_opt=Visibility=Internal --grpc-swift_opt=Server=true --grpc-swift_opt=Client=true --grpc-swift_opt=FileNaming=FullPath --grpc-swift_opt=UseAccessLevelOnImports=false
        protoc error output:
        Missing input file.

[0xifarouk]

I haven't been able to reproduce your issue in my Downloads folder, but our permissions might differ. You're showing screenshots of Xcode but mention .build in your error comment - can you give more information on how you're invoking the build (e.g. Xcode UI or swift build)?

Sorry about the confusion, the error I am getting is when trying to run the plugin via VS Code:

When running the plugin from Xcode from File -> Packages -> generate-grpc-code-from-protos it says Build Succeeded but nothing is being generated in the project directory.

[rnro]

Ah, I didn't realize that this was VS Code, I'll look into that.

If the Xcode build succeeds then that is successfully generating the code otherwise the static code referencing it would fail to build. Generated code isn't visible in the Xcode UI unless you jump to a definition for a generated symbol.

[rnro]

I see what the confusion is, generate-grpc-code-from-protos is the name of the SwiftPM command plugin rather than the build plugin

  // Code generator build plugin
  .plugin(
    name: "GRPCProtobufGenerator",
    capability: .buildTool(),
    dependencies: [
      .target(name: "protoc-gen-grpc-swift-2"),
      .product(name: "protoc-gen-swift", package: "swift-protobuf"),
    ]
  ),

  // Code generator SwiftPM command
  .plugin(
    name: "generate-grpc-code-from-protos",

The command plugin will generate source for a given proto file but it must be supplied as an argument, it's a CLI tool. I'm not sure if it's possible to hook that up via VS Code.

The build plugin forms part of the dependency graph (at least when used in Xcode) and the code is generated on demand and then built.

The config you are supplying in that JSON file is for the build plugin rather than the command plugin which is what you are invoking.

See https://swiftpackageindex.com/grpc/grpc-swift-protobuf/2.0.0/documentation/grpcprotobuf/generating-stubs.

[0xifarouk]

Ah, I didn't realize that this was VS Code, I'll look into that.

If the Xcode build succeeds then that is successfully generating the code otherwise the static code referencing it would fail to build.

What made me try VS Code is having no generated files in the package directory using Xcode, so I tried VS Code since it has more descriptive errors.
I was expecting some visible generated files, like what the swift-open-api-generator plugin does.

Generated code isn't visible in the Xcode UI unless you jump to a definition for a generated symbol.

How can I discover the symbol to jump for it? 😅
Also this makes it hard to share the sources between an iOS app & the Swift server for example, what I was doing in OpenAPI is to have a single package that hosts everything.

One last point is I was able to find the generated sources in:

• ~/gRPC-Demo/.build/plugins/outputs/grpc-demo/gRPC-Demo/destination/GRPCProtobufGenerator
• ~/gRPC-Demo/.build/index-build/plugins/outputs/grpc-demo/gRPC-Demo/destination/GRPCProtobufGenerator

I have deleted the files, but they are no longer being generated 😅
Still didn't find the client at all.

[0xifarouk]

The command plugin will generate source for a given proto file but it must be supplied as an argument, it's a CLI tool. I'm not sure if it's possible to hook that up via VS Code.

But why If I run it from the Xcode menu it works fine without error?

The build plugin forms part of the dependency graph (at least when used in Xcode) and the code is generated on demand and then built.

I am totally confused, what is the difference (if there is any) between:

• Only building the project in Xcode
• Running File -> Packages -> generate-grpc-code-from-protos
• Running generate-grpc-code-from-protos from VS Code

The config you are supplying in that JSON file is for the build plugin rather than the command plugin which is what you are invoking.

See swiftpackageindex.com/grpc/grpc-swift-protobuf/2.0.0/documentation/grpcprotobuf/generating-stubs.

This is my first time trying gRPC, and I found the docs confusing, still I wasn't able to get a single thing running and I am not sure what should I do in terms of steps to make it work correctly beside having protoc installed on my machine.
I just want the generated files, and the client 😅
The final goal is to have a package then make it a dependency for both the iOS app & the backend Swift server.

[rnro]

I'm sorry that you've had this experience, I think we should probably do a better job of documenting the command plugin.

When I said that files aren't shown by default I was referring to using the build plugin. For your use case the command plugin sounds like what you want.

I was expecting some visible generated files, like what the swift-open-api-generator plugin does.

Your link here is indeed referring to the command plugin, we also expose some functionality similar to this, it is chiefly different in that it takes its config as command line parameters, e.g.

swift package generate-grpc-code-from-protos --import-path /path/to/Protos -- /path/to/Protos/HelloWorld.proto

You can get a full listing by doing

swift package generate-grpc-code-from-protos --help

Using the command plugin in this way will generate the source code for you in a directory you can define (--output-path) as you would like.

I haven't yet had time to look into how that might be done via the VS Code or Xcode UIs because as you can see, it requires parameters to be provided. I do intend to look into that for you though.

Hopefully that information is enough to unblock you using a CLI for now. If anything is still unclear please let me know.

[0xifarouk]

Thank you for the help, and sorry for taking you time 🙏🏻
Unfortunately it's still not working with me 😅
I am running:
swift package generate-grpc-code-from-protos --import-path=./Protos --output-path=./Generated
but still getting this error:

Executable: /opt/homebrew/bin/protoc
	Arguments: --plugin=protoc-gen-grpc-swift=/Users/farouk/Developer/gRPC-Demo/.build/arm64-apple-macosx/debug/protoc-gen-grpc-swift-2-tool --grpc-swift_out=/Users/farouk/Developer/gRPC-Demo/.build/plugins/generate-grpc-code-from-protos/outputs/ --grpc-swift_opt=Visibility=Internal --grpc-swift_opt=Server=true --grpc-swift_opt=Client=true --grpc-swift_opt=FileNaming=FullPath --grpc-swift_opt=UseAccessLevelOnImports=false /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/--import-path=./Protos /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/--output-path=./Generated
	protoc error output:
	Could not make proto path relative: /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/--import-path=./Protos: No such file or directory

and I tried:
swift package generate-grpc-code-from-protos ./Protos --import-path=./Protos --output-path=./Generated
but got:

error: Code generation failed with: NSTaskTerminationReason(rawValue: 1):1.
	Executable: /opt/homebrew/bin/protoc
	Arguments: --plugin=protoc-gen-grpc-swift=/Users/farouk/Developer/gRPC-Demo/.build/arm64-apple-macosx/debug/protoc-gen-grpc-swift-2-tool --grpc-swift_out=/Users/farouk/Developer/gRPC-Demo/.build/plugins/generate-grpc-code-from-protos/outputs/ --grpc-swift_opt=Visibility=Internal --grpc-swift_opt=Server=true --grpc-swift_opt=Client=true --grpc-swift_opt=FileNaming=FullPath --grpc-swift_opt=UseAccessLevelOnImports=false /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos/ /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/--import-path=./Protos /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/--output-path=./Generated
	protoc error output:
	/Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos/: File does not reside within any path specified using --proto_path (or -I).  You must specify a --proto_path which encompasses this file.  Note that the proto_path must be an exact prefix of the .proto file names -- protoc is too dumb to figure out when two paths (e.g. absolute and relative) are equivalent (it's harder than you think).

[rnro]

No worries at all. In this case hopefully this is simple:

swift package generate-grpc-code-from-protos --import-path=./Protos --output-path=./Generated

should be

swift package generate-grpc-code-from-protos --import-path ./Protos --output-path ./Generated

Although I'm not sure if you can use relative paths.

[rnro]

Ah, you are also missing the section specifying the input files

 -- /path/to/Protos/HelloWorld.proto

the full invocation is of the form

swift package generate-grpc-code-from-protos --import-path /path/to/Protos -- /path/to/Protos/HelloWorld.proto

The --import-path ./Protos part here might be confusing you into thinking it will auto-discover the source files but that's not what it means. That is the path (or paths) in which protoc will look for other proto files referenced as imports for the file being generated.

[0xifarouk]

I have tried:

swift package generate-grpc-code-from-protos --import-path /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos -- /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos/helloworld.proto

it executed successfully, but there is no output files.
I tried:

swift package generate-grpc-code-from-protos --import-path /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos -- /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos/helloworld.proto -output-path /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Generated

but I got this error:

error: Code generation failed with: NSTaskTerminationReason(rawValue: 1):1.
	Executable: /opt/homebrew/bin/protoc
	Arguments: --plugin=protoc-gen-grpc-swift=/Users/farouk/Developer/gRPC-Demo/.build/arm64-apple-macosx/debug/protoc-gen-grpc-swift-2-tool --grpc-swift_out=/Users/farouk/Developer/gRPC-Demo/.build/plugins/generate-grpc-code-from-protos/outputs/ --proto_path=/Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos --grpc-swift_opt=Visibility=Internal --grpc-swift_opt=Server=true --grpc-swift_opt=Client=true --grpc-swift_opt=FileNaming=FullPath --grpc-swift_opt=UseAccessLevelOnImports=false /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Protos/helloworld.proto /Users/farouk/Developer/gRPC-Demo/--output-path /Users/farouk/Developer/gRPC-Demo/Sources/gRPC-Demo/Generated/
	protoc error output:
	Could not make proto path relative: /Users/farouk/Developer/gRPC-Demo/--output-path: No such file or directory

[0xifarouk]

After days of several trials, I was able to get it to work using protoc

protoc --proto_path=Sources/gRPC-Demo/Protos \
 --plugin=protoc-gen-grpc-swift=/opt/homebrew/bin/protoc-gen-grpc-swift-2 \
 --swift_out=Sources/gRPC-Demo/Generated \
 --grpc-swift_out=Sources/gRPC-Demo/Generated \
 Sources/gRPC-Demo/Protos/*.proto

This is working fine and as expected.
I really appreciate your help and time.

Should I close the issue, or keep it as a reference for new comers?