A simple C++ URL class

Usage

CMake

If you are developing your project with CMake you can include this library with the find_package mechanism of CMake. First, either run make install or include this project via add_subdirectory. Afterwards, you can link to this lib like so:

cmake_minimum_required(VERSION 3.4)

project(example_find_package)

find_package(CxxUrl REQUIRED)

add_executable(${PROJECT_NAME} main.cpp)

target_link_libraries(${PROJECT_NAME} PUBLIC chmike::CxxUrl)

The Url object API

Url is a C++ URL handling class with a very simple API. It's use is straightforward.

URIs that don't follow the URL standard defined in RFC3986 might not be correctly parsed in all cases.

• Construct an Url object

  Url u1;
  Url u2("http://www.example.com/");
  Url u3(u2);

• Assigning an url to an Url object

  u1=u2;
  u2="http://www.example.com/";

• Getting the url as a string

  std::string url_str=url.str();

• Clearing an Url object

  u1.clear();

• Getting the different fields of an Url object

  std::string scheme_str=u1.scheme();
  std::string user_info_str=u1.user_info();
  std::string host_str=u1.host();
  std::uint8_t ip_version=u1.ip_version();
  // 0=name, 4=IPv4, 6=IPv6,-1=undefined
  std::string port_str=u1.port();
  std::string path_str=u1.path();
  Url::Query query=u1.query();
  std::string fragment_str=u1.fragment();

• Setting the different fields of an Url object

  u1.clear().scheme("http").host("www.example.com").path("/");
  u1.add_query("q","some search key").add_query("fast");
  assert(u1.str()=="http://www.example.com/?q=some+search+key&fast");

• Accessing the key and values in the query

  u1.clear().add_query("a","b").add_query("c","d");
  assert(u1.query(0).val()=="b");
  assert(u1.query(1).key()=="c");
  assert(u1.str()=="?a=b&c=d");
  u1.set_query(0).val("B");
  u1.set_query(1).key("C");
  assert(u1.str()=="?a=B&C=d");

• Output of an Url object

  u1.str("http://www.example.com/?q=some+search+key&fast");
  std::stringstream str;
  str << u1;
  assert(str.str()=="Url:{url(http://www.example.com/?q=some+search+key&fast) "
         "scheme(http) host(www.example.com) IPv(0) path(/) "
         "query(<key(q) val(some search key)> <key(fast) val()>)}");

Implementation detail

The Url object uses lazy URL parsing and building. When a URL as string is assigned to the object, it is not immediatly parsed. It can then be assigned or moved to another Url object efficiently. The URL is parsed only when needed, which is before one of the fields is accessed or set, or when the object is output.

The URL is built only when the str() method is called or when the Url object is output.

Testing the library

In order to quickly build a static library and test the code, the following sequence of bash instructions may work for you.

g++ -c url.cpp
ar rvs CxxUrl.a url.o
g++ main.cpp CxxUrl.a
./a.out