aws-sdk-cpp does not work with cmake's find_package()

[timclemons]

Describe the bug
Attempting to use aws-sdk-cpp in nix-shell for development of a cmake-based project causes the build to fail with the following error:

CMake Error at /nix/store/fb5c1m733w8c4ci685nj4g5asdxwnmc9-aws-sdk-cpp-1.7.90-dev/lib/cmake/AWSSDK/AWSSDKConfig.cmake:97 (message):
  AWS SDK for C++ is missing, please install it first
Call Stack (most recent call first):
  CMakeLists.txt:3 (find_package)

To Reproduce
Steps to reproduce the behavior:

1. Create a shell.nix file with the following contents:

{ pkgs ? import <nixpkgs> {} }:
  pkgs.mkShell {
    buildInputs = [
      pkgs.gnumake
      pkgs.cmake
      pkgs.clang
      pkgs.aws-sdk-cpp
    ];
  }

2. In the same directory create a CMakeLists.txt with the following contents:

cmake_minimum_required(VERSION 3.15)
find_package(AWSSDK)

3. nix-shell && mkdir build && cd build && cmake ..

Expected behavior
Cmake would complete without error

Metadata
Please run nix run nixpkgs.nix-info -c nix-info -m and paste the result.

 - system: `"x86_64-linux"`
 - host os: `Linux 4.19.75, NixOS, 20.03pre194293.2436c27541b (Markhor)`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.3`
 - channels(tclemons): `""`
 - channels(root): `"nixos-20.03pre194293.2436c27541b"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
  - aws-sdk-cpp

[stale]

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[rehno-lindeque]

This is still important to me.

I have this error when trying to package https://github.com/aws/amazon-s3-plugin-for-pytorch which relies on aws-sdk-cpp:

CMake Error at /nix/store/kaaffkrfxgb9n53bbb9vagdhpxjlyzgj-aws-sdk-cpp-1.9.121-dev/lib/cmake/AWSSDK/AWSSDKConfig.cmake:86 (message):
  AWS SDK for C++ is missing, please install it first
Call Stack (most recent call first):
  CMakeLists.txt:9 (find_package)

generated by

{ buildPythonPackage
, fetchFromGitHub
, lib
, cmake
, aws-sdk-cpp
}:

let
  custom-aws-sdk-cpp = (aws-sdk-cpp.override {
    apis = ["s3" "transfer"];
    customMemoryManagement = false;
  });
in
buildPythonPackage rec {
  pname = "amazon-s3-plugin-for-pytorch";
  version = "0.0.1";
  src = fetchFromGitHub {
    owner = "aws";
    repo = pname;
    rev = "38284c8a5e92be3bbf47b08e8c90d94be0cb79e7";
    sha256 = "0lww4y3mq854za95hi4y441as4r3h3q0nyrpgj4j6kjk58gijbx9";
  };

  nativeBuildInputs = [
    cmake
  ];

  buildInputs = [
    custom-aws-sdk-cpp
  ];

  checkInputs = [
  ];

  propagatedBuildInputs = [
  ];

  meta = with lib; {
    description = "S3-plugin is a high performance PyTorch dataset library to efficiently access datasets stored in S3 buckets.";
    homepage = "https://github.com/aws/amazon-s3-plugin-for-pytorch";
    license = licenses.asl20;
    maintainers = with maintainers; [];
  };
}

[rehno-lindeque]

(As far as I can tell #85254 by @thequux doesn't seem to have resolved the issue)

[rehno-lindeque]

This is a workaround I found that fixes the issue:

let
  aws-sdk-cpp-s3-transfer = (aws-sdk-cpp.override {
    apis = ["s3" "transfer"];
  }).overrideAttrs (oldAttrs: {
  
    # Fixes cmake issue in dependent packages (see https://github.com/NixOS/nixpkgs/issues/70075)
    postPatch = oldAttrs.postPatch + ''
      substituteInPlace cmake/AWSSDKConfig.cmake \
        --replace "\''${AWSSDK_DEFAULT_ROOT_DIR}/\''${AWSSDK_INSTALL_INCLUDEDIR}" "\''${AWSSDK_INSTALL_INCLUDEDIR}"
    '';

  });
in
  mkDerivation { ... }

Hence, it should be possible to trace back to the root problem from here:

https://github.com/aws/aws-sdk-cpp/blob/74a1396f93bdcd5e3c3bed25fa73ac472961e55e/cmake/AWSSDKConfig.cmake#L79-L96

if (AWSSDK_ROOT_DIR)
    find_file(AWSSDK_CORE_HEADER_FILE Aws.h
            "${AWSSDK_ROOT_DIR}/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
            "${AWSSDK_DEFAULT_ROOT_DIR}/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
            )
else()
    find_file(AWSSDK_CORE_HEADER_FILE Aws.h
        "${AWSSDK_DEFAULT_ROOT_DIR}/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "/usr/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "/usr/local/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "C:/Progra~1/AWSSDK/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "C:/Program Files/AWSSDK/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "C:/Program Files/aws-cpp-sdk-all/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "C:/Program Files (x86)/aws-cpp-sdk-all/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
        "C:/AWSSDK/${AWSSDK_INSTALL_INCLUDEDIR}/aws/core"
    )
endif()

I'm not clear as to why/how these variables end up different when using find_package(AWSSDK)

[rehno-lindeque]

Seems like ff3f5bb#diff-bb198faaa0e40668ef72c8354e3e431dfd37426d45229c6f3c6fa3174652d570 removes the code in cmake-dirs.patch that deals with this.

Partially rolling back this change appears as though it might solve the problem.

[Artturin]

@jmklix does your aws/aws-sdk-cpp#2630 make the patch unnecessary?

After comparing yes it does

#267232

[Artturin]

This was fixed by f7557ec

Added a test to #267232