README.md

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# Pulsar C++ client library

Examples for using the API to publish and consume messages can be found under the [examples](https://github.com/apache/pulsar-client-cpp/tree/main/examples) folder.

## Generate the API documents

Pulsar C++ client uses [doxygen](https://www.doxygen.nl) to build API documents. After installing `doxygen`, you only need to run `doxygen` to generate the API documents whose main page is under the `doxygen/html/index.html` path.

## Requirements

* A C++ compiler that supports C++11, like GCC >= 4.8
* CMake >= 3.13
* [Boost](http://www.boost.org/)
* [Protocol Buffer](https://developers.google.com/protocol-buffers/) >= 3
* [libcurl](https://curl.se/libcurl/)
* [openssl](https://github.com/openssl/openssl)

The default supported [compression types](include/pulsar/CompressionType.h) are:

* `CompressionNone`
* `CompressionLZ4`

If you want to enable other compression types, you need to install:

* `CompressionZLib`: [zlib](https://zlib.net/)
* `CompressionZSTD`: [zstd](https://github.com/facebook/zstd)
* `CompressionSNAPPY`: [snappy](https://github.com/google/snappy)

If you want to build and run the tests, you need to install [GTest](https://github.com/google/googletest). Otherwise, you need to add CMake option `-DBUILD_TESTS=OFF`.

If you want to use `ClientConfiguration::setLogConfFilePath`, you need to install the [Log4CXX](https://logging.apache.org/log4cxx) and add CMake option `-DUSE_LOG4CXX=ON`.

## Platforms

Pulsar C++ Client Library has been tested on:

* Linux
* Mac OS X
* Windows x64

## Compilation

### Clone

First of all, clone the source code:

```shell
git clone https://github.com/apache/pulsar-client-cpp
cd pulsar-client-cpp
```

### Compile on Ubuntu

#### Install all dependencies:

```shell
sudo apt-get update -y && sudo apt-get install -y g++ cmake libssl-dev libcurl4-openssl-dev \
                libprotobuf-dev libboost-all-dev libgtest-dev libgmock-dev \
                protobuf-compiler
```

#### Compile Pulsar client library:

```shell
cmake .
make
```

#### Checks

Client library will be placed in:

```
lib/libpulsar.so
lib/libpulsar.a
```

Tools will be placed in:

```
perf/perfProducer
perf/perfConsumer
```

### Compile on Mac OS X

#### Install all dependencies:

```shell
brew install cmake openssl protobuf boost boost-python3 googletest zstd snappy
```

#### Compile Pulsar client library:

```shell
cmake .
make
```

#### Checks

Client library will be placed in:

```
lib/libpulsar.dylib
lib/libpulsar.a
```

Tools will be placed in:

```
perf/perfProducer
perf/perfConsumer
```

### Compile on Windows

#### Install with [vcpkg](https://github.com/microsoft/vcpkg)

It's highly recommended to use `vcpkg` for C++ package management on Windows. It's easy to install and well supported by Visual Studio (2015/2017/2019) and CMake. See [here](https://github.com/microsoft/vcpkg#quick-start-windows) for quick start.

Take Windows 64-bit library as an example, you only need to run

```bash
vcpkg install --feature-flags=manifests --triplet x64-windows
```

> NOTE: For Windows 32-bit library, change `x64-windows` to `x86-windows`, see [here](https://github.com/microsoft/vcpkg/blob/master/docs/users/triplets.md) for more details about the triplet concept in Vcpkg.

The all dependencies, which are specified by [vcpkg.json](vcpkg.json), will be installed in `vcpkg_installed/` subdirectory,

With `vcpkg`, you only need to run two commands:

```bash
cmake \
 -B ./build \
 -A x64 \
 -DBUILD_TESTS=OFF \
 -DVCPKG_TRIPLET=x64-windows \
 -DCMAKE_BUILD_TYPE=Release \
 -S .
cmake --build ./build --config Release
```

Then all artifacts will be built into `build` subdirectory.

> **NOTE**:
>
> 1. For Windows 32-bit, you need to use `-A Win32` and `-DVCPKG_TRIPLET=x86-windows`.
> 2. For MSVC Debug mode, you need to replace `Release` with `Debug` for both `CMAKE_BUILD_TYPE` variable and `--config` option.

#### Install dependencies manually

You need to install [dlfcn-win32](https://github.com/dlfcn-win32/dlfcn-win32) in addition.

If you installed the dependencies manually, you need to run

```shell
#If all dependencies are in your path, all that is necessary is
cmake .

#if all dependencies are not in your path, then passing in a PROTOC_PATH and CMAKE_PREFIX_PATH is necessary
cmake -DPROTOC_PATH=C:/protobuf/bin/protoc -DCMAKE_PREFIX_PATH="C:/boost;C:/openssl;C:/zlib;C:/curl;C:/protobuf;C:/googletest;C:/dlfcn-win32" .

#This will generate pulsar-cpp.sln. Open this in Visual Studio and build the desired configurations.
```

#### Checks

Client library will be placed in:

```
build/lib/Release/pulsar.lib
build/lib/Release/pulsar.dll
```

#### Examples

Add windows environment paths:

```
build/lib/Release
vcpkg_installed
```

Examples will be available in:

```
build/examples/Release
```

## Tests

```shell
# Execution
# Start standalone broker
./pulsar-test-service-start.sh

# Run the tests
cd tests
./pulsar-tests

# When no longer needed, stop standalone broker
./pulsar-test-service-stop.sh
```

## Wireshark Dissector

See the [wireshark](wireshark/) directory for details.

## Requirements for Contributors

It's required to install [LLVM](https://llvm.org/builds/) for `clang-tidy` and `clang-format`. Pulsar C++ client use `clang-format` **11** to format files.  `make format` automatically formats the files.

For Ubuntu users, you can install `clang-format-11` via `apt install clang-format-11`. For other users, run `./build-support/docker-format.sh` if you have Docker installed.

We welcome contributions from the open source community, kindly make sure your changes are backward compatible with GCC 4.8 and Boost 1.53.