ENG 09 0 References request

The HttpRequest type pointer commonly named req in the examples in this documentation represents the data contained in a request received or sent by drogon, below are the some methods by which you can interact with this object:

• isOnSecureConnection()

  Summary:

  Function that returns if the request was made on https.

  Inputs:

  None.

  Returns:

  bool type.

• getMethod()

  Summary:

  Function that returns the request method. Useful to differentiate the request method if a single handle allows more than one type.

  Inputs:

  None.

  Returns:

  HttpMethod request method object.

  Examples:

  #include "mycontroller.h"
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      if (req->getMethod() == HttpMethod::Get) {
        // do something
      } else if (req->getMethod() == HttpMethod::Post) {
        // do other something
      }
  }

• getParameter(const std::string &key)

  Summary:

  Function that returns the value of a parameter based on an identifier. The behavior changes based on the Get or Post request type.

  Inputs:

  string type identifier of param.

  Returns:

  param content on string format.

  Examples:

  On Get type:

  #include "mycontroller.h"
  #include <string>
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      // https://mysite.com/an-path/?id=5
      std::string id = req->getParameter("id");
      // or 
      long id = std::strtol(req->getParameter("id"));
  }

  Or On Post type:

  #include "mycontroller.h"
  #include <string>
  
  using namespace drogon;
  
  void mycontroller::loginHandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      // request contain a Form Login
      std::string email = req->getParameter("email");
       
      std::string password = req->getParameter("password");
  }

• getPath()

  Similar:

  path()

  Summary:

  Function that returns the request path. Useful if you use an ADD_METHOD_VIA_REGEX or other type of dynamic URL in the controller.

  Inputs:

  None.

  Returns:

  string representing the request path.

  Examples:

  #include "mycontroller.h"
  #include <string>
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      // https://mysite.com/an-path/?id=5
      std::string url = req->getPath();
      
      // url = /an-path/
  }

• getBody()

  Similar:

  body()

  Summary:

  Function that returns the request body content (if any).

  Inputs:

  None.

  Returns:

  String representing the request body (if any).

• getHeader(std::string key)

  Summary:

  Function that returns a request header based on an identifier.

  Inputs:

  String header identifier.

  Returns:

  The content of the header in string format.

  Examples:

  #include "mycontroller.h"
  #include <string>
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      if (req->getHeader("Host") != "mysite.com") {
        // return http 403 
      }
  }

• headers()

  Summary:

  Function that returns all headers of a request.

  Inputs:

  None.

  Returns:

  An unordered_map containing the headers.

  Examples:

  #include "mycontroller.h"
  #include <unordered_map>
  #include <string>
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      for (const std::pair<const std::string, const std::string> &header : req->headers()) {
        auto header_key = header.first;
        auto header_value = header.second;
      }
  }

• getCookie()

  Summary:

  Function that returns request cookie based on an identifier.

  Inputs:

  None.

  Returns:

  Value of cookie on string format.

• cookies()

  Summary:

  Function that returns all cookies of a request.

  Inputs:

  None.

  Returns:

  An unordered_map containing the cookies.

  Examples:

  #include "mycontroller.h"
  #include <unordered_map>
  #include <string>
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      for (const std::pair<const std::string, const std::string> &header : req->cookies()) {
        auto cookie_key = header.first;
        auto cookie_value = header.second;
      }
  }

• getJsonObject()

  Summary:

  Function that converts the body value of a request into a Json object (normally POST requests).

  Inputs:

  None.

  Returns:

  A Json object.

  Examples:

  #include "mycontroller.h"
  
  using namespace drogon;
  
  void mycontroller::anyhandle(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
      // body = {"email": "[email protected]"}
      auto jsonData = *req->getJsonObject();
  
      std::string email = jsonData["email"].asString();
  }

Useful Things

From here are not methods of the Http Request object, but some useful things you can do to process the requests you will receive

Parsing File Request

#include "mycontroller.h"

using namespace drogon;

void mycontroller::postfile(const HttpRequestPtr &req, std::function<void (const HttpResponsePtr &)> &&callback) {
    // Only Post Requests (File Form)

    MultiPartParser file;
    file.parse(req);

    if (file.getFiles().empty()) {
      // Not Files Found
    }

    // Get First file and save then
    const HttpFile archive = file.getFiles()[0];
    archive.saveAs("/tmp/" + archive.getFileName());
  }

For more information about parsing file: File Handler

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