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# webcc
C++ client and server library for HTTP and REST based on *Boost Asio*.
Please turn to our [Wiki](https://github.com/sprinfall/webcc/wiki) (under construction) for more tutorials and guides.
## Client API Examples
A complete client example:
```cpp
#include <iostream>
#include "webcc/http_client_session.h"
#include "webcc/logger.h"
int main() {
// Configure logger.
WEBCC_LOG_INIT("", webcc::LOG_CONSOLE);
// Session provides convenient request APIs, stores request configurations
// and manages persistent connenction.
webcc::HttpClientSession session;
// Catch exceptions for error handling.
try {
// Send a HTTP GET request.
auto r = session.Get("http://httpbin.org/get");
// Print the response content data.
std::cout << r->content() << std::endl;
} catch (const webcc::Exception& e) {
std::cout << e.what() << std::endl;
}
return 0;
}
```
The `Get()` method is nothing but a shortcut of `Request()`. Using `Request()` directly is more complicated:
```cpp
auto r = session.Request(webcc::HttpRequestBuilder{}.Get().
Url("http://httpbin.org/get")
());
```
As you can see, a helper class named `HttpRequestBuilder` is used to chain the parameters and finally build (don't miss the `()` operator) a request object.
Both the shortcut and `Request()` accept URL query parameters:
```cpp
// Query parameters are passed using a std::vector.
session.Get("http://httpbin.org/get", { "key1", "value1", "key2", "value2" });
session.Request(webcc::HttpRequestBuilder{}.Get().
Url("http://httpbin.org/get").
Query("key1", "value1").
Query("key2", "value2")
());
```
Adding additional headers is also easy:
```cpp
r = session.Get("http://httpbin.org/get",
{"key1", "value1", "key2", "value2"},
{"Accept", "application/json"}); // Also a std::vector
session.Request(webcc::HttpRequestBuilder{}.Get().
Url("http://httpbin.org/get").
Query("key1", "value1").
Query("key2", "value2").
Header("Accept", "application/json")
());
```
Accessing HTTPS has no difference from HTTP:
```cpp
session.Get("https://httpbin.org/get");
```
*NOTE: The HTTPS/SSL support requires the build option `WEBCC_ENABLE_SSL` to be enabled.*
Listing GitHub public events is not a big deal:
```cpp
auto r = session.Get("https://api.github.com/events");
```
You can then parse `r->content()` to JSON object with your favorite JSON library. My choice for the examples is [jsoncpp](https://github.com/open-source-parsers/jsoncpp). But the library itself doesn't understand JSON nor require one. It's up to you to choose the most appropriate JSON library.
## Build Instructions
### General
A lot of C++11 features are used, e.g., `std::move`.
VS2013 and above is required for building `webcc` on Windows.
[CMake 3.1.0+](https://cmake.org/) is used as the build system. But if you don't use CMake, you can just copy the `src/webcc` folder to your own project then manage it by yourself, though some changes are needed to make it work. See [Wiki/Integrate Into Your Project]( https://github.com/sprinfall/webcc/wiki/Integrate-Into-Your-Project) for more details.
[C++ Boost](https://www.boost.org/) should be 1.66+ because Asio made some broken changes to the API since 1.66.
OpenSSL is required for HTTPS support. See `WEBCC_ENABLE_SSL` option.
Zlib is required for compressing and decompressing HTTP requests and responses. Already included in the `third_party` folder for Windows.
### Build Options
The following CMake options determine how you build the projects. They are quite self-explanatory.
```cmake
option(WEBCC_ENABLE_TEST "Build test?" ON)
option(WEBCC_ENABLE_UNITTEST "Build unit test?" ON)
option(WEBCC_ENABLE_EXAMPLES "Build examples?" ON)
set(WEBCC_ENABLE_LOG 1 CACHE STRING "Enable logging? (1:Yes, 0:No)")
set(WEBCC_LOG_LEVEL 2 CACHE STRING "Log level (0:VERB, 1:INFO, 2:WARN, 3:ERRO or 4:FATA)")
set(WEBCC_ENABLE_SSL 0 CACHE STRING "Enable SSL/HTTPS (need OpenSSL)? (1:Yes, 0:No)")
```
Options `WEBCC_ENABLE_LOG` and `WEBCC_LOG_LEVEL` together define how logging behaves. See [Wiki/Logging](https://github.com/sprinfall/webcc/wiki/Logging) for more details.
You should install OpenSSL development files before try to enable `WEBCC_ENABLE_SSL`.
### Build on Linux
Create a build folder under the root (or any other) directory, and `cd` to it:
```bash
mkdir build
cd build
```
Generate Makefiles with the following command:
```bash
cmake -G"Unix Makefiles" \
-DCMAKE_INSTALL_PREFIX=~ \
-DWEBCC_ENABLE_LOG=1 \
-DWEBCC_LOG_LEVEL=2 \
-DWEBCC_ENABLE_SSL=ON \
-DWEBCC_ENABLE_UNITTEST=ON \
-DWEBCC_ENABLE_UNITTEST=ON \
-DWEBCC_ENABLE_EXAMPLES=ON \
..
```
Feel free to change the build options.
CMake variable `CMAKE_INSTALL_PREFIX` defines where to install the output library and header files. The default is `/usr/local`.
If everything is OK, then you can build with `make`:
```bash
$ make -j4 # or -j8, depending on how many CPU cores you have.
```
Then install:
```bash
$ make install
```