src/net/http_client.h

// Copyright 2010-2015, Google Inc.
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#ifndef MOZC_NET_HTTP_CLIENT_H_
#define MOZC_NET_HTTP_CLIENT_H_

#include <string>
#include <vector>

#include "base/port.h"

namespace mozc {

// Simple synchronous HTTP client
//
// Usage:
// 1) Simple GET
// string output;
// CHECK(mozc::HTTPClient::Get("http://www.google.com/", &output));
//
// 2) GET with some manual options.
// mozc::HTTPClient::Option option;
// option.timeout = 200;     // get data within 200msec
// option.headers.push_back("Host: foo.bar.com"); // replace/add header
// CHECK(mozc::HTTPClient::Get("http://www.google.com/", option, &output));
//
// 3) Rewrite an actual implementation (for unittesting)
// class MyHandler: public HTTPClientInterface { .. };
// MyHandler handler;
// mozc::HTTPClient::SetHTTPClientInterface(handler);
class HTTPClientInterface;

class HTTPClient {
 public:
  struct Option {
    bool   include_header;       // include header in output
    size_t max_data_size;        // maximum data size client can retrieve
    int32  timeout;              // timeout
    vector<string> headers;      // additional headers;

    // set default parameter
    Option()
        : include_header(false),
          max_data_size(10 * 1024 * 1024),  // 10Mbyte
          timeout(600000) {}  // 10min
  };

  // Synchronous HTTP GET, HEAD and POST

  // string interface
  static bool Get(const string &url, string *output);
  static bool Head(const string &url, string *output);
  static bool Post(const string &url, const string &data, string *output);

  static bool Get(const string &url, const Option &option, string *output);
  static bool Head(const string &url, const Option &option, string *output);
  static bool Post(const string &url, const string &data,
                   const Option &option, string *output);

  // Inject a dependency for unittesting
  static void SetHTTPClientHandler(const HTTPClientInterface *handler);

 private:
  DISALLOW_IMPLICIT_CONSTRUCTORS(HTTPClient);
};

// Interface class for injecting an actual implementation
class HTTPClientInterface {
 public:
  HTTPClientInterface() {}
  virtual ~HTTPClientInterface() {}

  virtual bool Get(const string &url, const HTTPClient::Option &option,
                   string *output) const = 0;
  virtual bool Head(const string &url, const HTTPClient::Option &option,
                    string *output) const = 0;
  virtual bool Post(const string &url, const string &data,
                    const HTTPClient::Option &option,
                    string *output) const = 0;
};
}  // namespace mozc
#endif  // MOZC_NET_HTTP_CLIENT_H_