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# Apache NiFi -  MiNiFi - C++ Windows Build Guide

## Requirements

Apache NiFi MiNiFi C++ has been built on Window Server 2016, 2019, and Windows 10 operating systems. The project is CMake focused we suggest building via Visual Studio 2019 or our `win_build_vs.bat` script.

The project previously required OpenSSL to be installed. If you follow our build procedures, below, you will not need to install that dependency.

### Required software

 - Visual Studio 2019
 - [CMake](https://cmake.org/download/)
 - [Git](https://git-scm.com/download/win) (the build process requires the bash.exe and patch.exe tools packaged with Git)
 - (Optional) [WiX Toolset](https://wixtoolset.org/releases/) (only for building the MSI)
 - (Optional) JDK (only for JNI support)

### JNI support
Though the project is written in C++, JNI functionality supports running Java processors stored in NiFi Archives. These can be run
in a much smaller memory footprint and consume fewer resources. If your systems do not support Java or you do not want a JDK installed, please use non-JNI builds.

## Building with Visual Studio

Make sure your Visual Studio installation includes the "Visual C++ tools for CMake" and "Visual C++ ATL for x86 and x64" options.
You can also add these after installation using the Visual Studio Installer app. We also advise
installing WiX and Visual Studio Command Prompt via the marketplace. To do this please go to the Tools Menu, followed by Extensions and Updates. Once the popup displays you
may install additional features from Online sources in the Online menu.

A file named CMakeSettings.json provides the CMake configuration.

CMake must generate its cache, under Cache in the CMake Menu. After that is complete go to 'Build Only' under the CMake menu. Due to limitations in Visual Studio's CMake support, it is advised
that you build `minifi.lib` then `minifi.exe` targets.  `Build All` works, too, but it takes much longer.
Once you have built these targets, you may use the `cpack` command to build your MSI. If you are building with JNI functionality the MSI will be
significantly larger (about 160 MB) since it contains the base NARs to run the standard set of Apache NiFi processors.

## Building via the build script

The preferred way of building the project is via the `win_build_vs.bat` script found in our root source folder. Its first parameter is mandatory, the directory in which it will build the project. `build` is a good default choice for this.

After the build directory it will take optional parameters modifying the CMake configuration used in the build:

| Argument | Effect |
|----------|------------------------------------------------|
| /T | Disables building tests |
| /R | Disables automatic test running after build |
| /P | Enables MSI creation |
| /K | Enables Kafka extension |
| /J | Enables JNI |
| /S | Enables SQL |
| /C | Enables CoAP |
| /A | Enables AWS |
| /Z | Enables Azure |
| /L | Enables Linter |
| /O | Enables OpenCV |
| /PDH | Enables Performance Monitor |
| /PR | Enables Prometheus |
| /RO | Use real ODBC driver in tests instead of mock SQL driver |
| /M | Creates installer with merge modules |
| /64 | Creates 64-bit build instead of a 32-bit one |
| /D | Builds RelWithDebInfo build instead of Release |
| /DD | Builds Debug build instead of Release |
| /CI | Sets STRICT_GSL_CHECKS to AUDIT |
| /NINJA | Uses Ninja build system instead of MSBuild |

Examples:
 - 32-bit build with kafka, disabling tests, enabling MSI creation: `win_build_vs.bat build32 /T /K /P`
 - 64-bit build with JNI, with debug symbols: `win_build_vs.bat build64 /64 /J /D`

`win_build_vs.bat` requires a Visual Studio 2019 build environment to be set up. Use the `x86 Native Tools Command Prompt for VS 2019`, or the `x64 Native Tools Command Prompt for VS 2019` for 32-bit and 64-bit builds respectively.

You can specify additional CMake arguments by setting the EXTRA_CMAKE_ARGUMENTS variable:
```
> set EXTRA_CMAKE_ARGUMENTS=-DCOMPANY_NAME="Acme Inc" -DPRODUCT_NAME="Roadrunner Stopper"
> win_build_vs.bat ...
```

## Building directly with CMake

The project can also be built manually using CMake. It requires the same environment the build script does (the proper Native Tools Command Prompt).

A basic working CMake configuration can be inferred from the `win_build_vs.bat`.

`win_build_vs.bat /64 /P` is equivalent to running the following commands:

```
mkdir build
cd build
cmake -G "Visual Studio 16 2019" -DINSTALLER_MERGE_MODULES=OFF -DENABLE_SQL=OFF -DCMAKE_BUILD_TYPE_INIT=Release -DCMAKE_BUILD_TYPE=Release -DWIN32=WIN32 -DENABLE_LIBRDKAFKA=OFF -DENABLE_JNI=OFF -DOPENSSL_OFF=OFF -DENABLE_COAP=OFF -DUSE_SHARED_LIBS=OFF -DDISABLE_CONTROLLER=ON  -DBUILD_ROCKSDB=ON -DFORCE_WINDOWS=ON -DUSE_SYSTEM_UUID=OFF -DDISABLE_LIBARCHIVE=OFF -DDISABLE_SCRIPTING=ON -DENABLE_WEL=TRUE -DFAIL_ON_WARNINGS=OFF -DSKIP_TESTS=OFF ..
msbuild /m nifi-minifi-cpp.sln /property:Configuration=Release /property:Platform=Win32
copy minifi_main\Release\minifi.exe minifi_main\
cpack
ctest -C Release
```