Swift Package Manager 5.1.0 missing SwiftGRPC on Import

[trujamal]

New Issue Checklist

• Updated grpc-swift to the latest version
• I read the Contribution Guidelines
• I searched for existing GitHub issues(especially, there are many resolved issues related to SSL)

Issue Description

Starting with an Swift UI application in Xcode

1. Single View App
2. Enter Required Info
3. Unchecked Include Unit Tests / Include UI Tests
4. Went to add package dependency
5. Used the following url https://github.com/grpc/grpc-swift
6. Selected Branch and typed in nio
7. Confirmed that under Package Product the only fields were GRPC | Library | Name Of Project
8. Clicked Finish
9. Went to SceneDelegate.swift then proceeded to type in import SwiftGRPC
10. Resulting error of No such module SwiftGRPC
11. Types in GRPC instead via this route and has no issues
12. Import the .grpc and .pb.swift files as mentioned here, medium starter
13. As a result inside of the files the following message is shown in step 10.

Unsure of how to proceed based upon the documentation in the readMe, also looking into the following Stack Overflow thread this solution did not appear to work either. Any help would be appreciated.

Thanks

Complete output when running grpc-swift, including the stack trace and command used

No such module `SwiftGRPC`

Environment

Key
Value




OS Version
10.15.3


Swift Version
5.1.3


Xcode Version
11.3.1


gRPC-Swift Version
1.0.0-alpha.9


gRPC-Swift Version
1.0.0-alpha.9


protoc Version
3.11.3


protoc-gen-swift Version
1.5.0


protoc-gen-swiftgrpc Version
?.?.?



  

[weissi]

@trujamal the module is called GRPC, not SwiftGRPC, right? Can't you just remove the import SwiftGRPC line and replace it by import GRPC?

[trujamal]

@weissi then in that case the other lines precede the code will throw an error due to the GRPC library not having the same methods. I get error messages such as unresolved identifiers for all of the methods that the protoc generates based upon the Proto file.

For example the difference between the pod file and the swift package is wherein the PodFile does include a folder director of SwiftGRPC, that contains files such as ClientCall / ClientCallUnary which depend on the protoc generation. While within the SPM version uses completely different files. Is that behavior normal?

[demistry]

Having this same issue as well...

[demistry]

Have you been able to fix it?
I have updated literally almost everything there is to update and still nothing..

[weissi]

CC @timburks / @MrMage

[trujamal]

@demistry The partial solution I found is based off of a separate solution thread that @nakkht left a simple answer to.

It seems to work pretty well!
Steps to setup:

• Sync to master branch of grpc-swift
• Replace Package.swift contents with the following:

// swift-tools-version:5.1

import PackageDescription
import Foundation

var packageDependencies: [Package.Dependency] = [
  .package(url: "https://github.com/apple/swift-protobuf.git", .upToNextMajor(from: "1.5.0")),
  .package(url: "https://github.com/kylef/Commander.git", .upToNextMinor(from: "0.8.0"))
]

var cGRPCDependencies: [Target.Dependency] = []

#if os(Linux)
let isLinux = true
#else
let isLinux = false
#endif

if isLinux || ProcessInfo.processInfo.environment.keys.contains("GRPC_USE_OPENSSL") {
  packageDependencies.append(.package(url: "https://github.com/apple/swift-nio-ssl-support.git", from: "1.0.0"))
} else {
  cGRPCDependencies.append("BoringSSL")
}

let package = Package(
    name: "SwiftGRPC",
    products: [
        .library(name: "SwiftGRPC", targets: ["SwiftGRPC"])
    ],
    dependencies: packageDependencies,
    targets: [
        .target(name: "SwiftGRPC",
                dependencies: ["CgRPC", "SwiftProtobuf"]),
        .target(name: "CgRPC",
                dependencies: cGRPCDependencies,
                cSettings: [
                    .headerSearchPath("../BoringSSL/include", .when(platforms: [.iOS, .macOS, .tvOS, .watchOS])),
                    .unsafeFlags(["-Wno-module-import-in-extern-c"])],
                linkerSettings: [.linkedLibrary("z")]),
        .target(name: "protoc-gen-swiftgrpc",
                dependencies: [
                    "SwiftProtobuf",
                    "SwiftProtobufPluginLibrary",
                    "protoc-gen-swift"]),
        .target(name: "BoringSSL"),
        .testTarget(name: "SwiftGRPCTests", dependencies: ["SwiftGRPC"]),
    ],
    swiftLanguageVersions: [.v4, .v4_2, .version("5")],
    cLanguageStandard: .gnu11,
    cxxLanguageStandard: .cxx11)

• Try building
• Success!

Right after committed and referenced local grpc-swift repo with the commit to my project.
Worked right out of the box (after removing carthage integration)

Is it something we could have with version 0.10.1?

Effectively by forking this repository (master branch / nio) into your own versioning, and updating the Package.swift file to the information above, then it will install the necessary packages. I believe the main reason why is that inside of the nio branch there are no source files or any references to SwiftGRPC unlike the master branch. Also the package.swift file inside of the nio repository may need to be updated to include the 5.1.0 tag instead of the 5.0.0 tag. So even then the nio branch needs to updated with the Swift GRPC dependency due to protobuf and swift_protobuf requiring that library.

TLDR:
Fork the repository, and replace the Package.swift contents with the contents above and set the package dependency url to your fork.

[glbrntt]

@trujamal sorry for the slow response here; I've been away.

12. Import the .grpc and .pb.swift files as mentioned here, medium starter

The tutorial linked is for the old version of (aka SwiftGRPC); the missing files you're seeing here are for that version of gRPC Swift. I.e. you're using generated code for the old version with the runtime for the new version (GRPC).

The instructions for generating the code from that article broadly apply to the new version as well. However they are not specific enough:

Once you have the .proto file, we need a SwiftGRPC plugin to convert the .proto files into .swift and .pb.swift files. In order to do that, we need to clone the SwiftGRPC open source project.

This is correct but you must also checkout the version of gRPC Swift that is resolved in Package.resolved (or Package.swift if you depend on an exact version).

TLDR:
Fork the repository, and replace the Package.swift contents with the contents above and set the package dependency url to your fork.

This isn't necessary unless you want to build the old version with Xcode via Swift Package Manager.

[demistry]

On a final note use the command protoc --grpc-swift_out=. instead of protoc --swiftgrpc_out=. to build and convert your proto files

[ohayon]

I am running into this issue currently in Swift 5.2 where it is trying to import SwiftGRPC, and the above fix that @demistry mentioned does not fix the issue 😞 .

[ohayon]

Instead of import SwiftGRPC? And this is in the generated .pb.swift file right? That does not seem to fix the issue at all.

[ohayon]

Sorry, I am a bit confused here. in the generated file, these are the imports

import Dispatch
import Foundation
import SwiftGRPC
import SwiftProtobuf

[ohayon]

and the SwiftGRPC import fails, if i remove that, there are build failures all over for undeclared types like ClientCallUnaryBase and Metadata among many others.

[trujamal]

Instead of import SwiftGRPC? And this is in the generated .pb.swift file right? That does not seem to fix the issue at all.

Inside of my .pb.swift file the following imports are as follows:

import Foundation
import SwiftProtobuf

While my wrapper functions use the following imports to interface with the grpc client

import GRPC
import NIO
import NIOSSL
import Logging

If neither of those work, then verify that the protobuf information located within the local folder is up to date with the latest compiler. The instructions are located lower within the response.

Sorry, I am a bit confused here. in the generated file, these are the imports

import Dispatch
import Foundation
import SwiftGRPC
import SwiftProtobuf

and the SwiftGRPC import fails, if i remove that, there are build failures all over for undeclared >types like ClientCallUnaryBase and Metadata among many others.

According to this result you are using an outdated version of the compiler located within the local/bin/protoc-gen-grpc-swift and local/bin/protoc-gen-swift . Last time I've updated the compiler on my end was March 22nd 2020, in which was based on the newly merged master branch that has the latest code.

Protobuf Documentation

There are two different methods of getting it setup.

Apple Protobuf Documentation

or

git clone git@github.com:grpc/grpc-swift.git
cd grpc-swift
make
sudo cp protoc-gen-swift protoc-gen-grpc-swift /usr/local/bin