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+# PeerConnect
+
+### Table of Contents
+* Constructor
+ * [PeerConnect()](#classpeerconnect)
+* Methods
+ * [Open()](#open)
+ * [Close()](#close)
+ * [Connect()](#connect)
+ * [Send()](#send)
+* Events
+ * [On("open")](#onopen)
+ * [On("close")](#onclose)
+ * [On("connect")](#onconnect)
+ * [On("message")](#onmessage)
+ * [On("writable")](#onwritable)
+* Static Methods
+ * [PeerConnect::Run()](#run)
+ * [PeerConnect::Stop()](#stop)
+* Example
+ * [echo_server](#echoserver)
+ * [echo_client](#echoclient)
+
+
+## Include
+
+Include following at the top of your code
+
+```c++
+#include "peerconnect.h"
+```
+
+## Class: PeerConnect
+
+This class is a PeerConnect server and client.
+
+## Constructor
+
+<a name="classpeerconnect"/>
+### PeerConnect()
+
+Construct a new PeerConnect object. A `peer` is local name of peer and remote peer may connect to local peer with `peer` name.
+
+```c++
+PeerConnect( 
+  const std::string peer = ""
+)
+```
+
+Parameters
+
+> **peer** [optional]
+> * `peer` is a local name of peer. Remote peers may connect to local peer by `peer`.
+
+Examples
+
+```c++
+PeerConnect pc1;
+PeerConnect pc2("PEER_NAME");
+PeerConnect pc3("Your@email.com");
+```
+
+## Methods
+
+<a name="open"/>
+### Open()
+
+Initialize a peer. It is required to call `Open()` before calling other methods like Send(), Connect() and On().
+
+```c++
+void Open()
+```
+
+<a name="close"/>
+### Close()
+
+Close the remote peer connection or connection attempt, if any. If the connection is already closed, this method does nothing.
+
+```c++
+void Close(
+  const std::string peer = ""
+)
+```
+
+Parameters
+
+> **peer** [optional]
+> * Close a remote `peer` if peer is provide. Otherwise close all local and remote peers.
+
+<a name="connect"/>
+### Connect()
+
+Connect to remote peer.
+
+```c++
+void Connect(
+  const std::string peer
+)
+```
+
+Parameters
+
+> **peer**
+> * A name of peer connect to.
+
+<a name="send"/>
+### Send()
+
+Transmits data to the peer over p2p connection.
+
+```c++
+bool Send(
+  const std::string& peer,
+  const char* data,
+  const size_t size,
+  const bool wait = SYNC_OFF
+)
+
+bool Send(
+  const string& peer,
+  const string& data,
+  const bool wait = SYNC_OFF
+)
+```
+
+Parameters
+
+> * peer : A name of peer receiving data
+> * data : A data to send
+> * size : A size of data
+> * wait : SYNC_ON if synchronously send a data and SYNC_OFF if asynchronously send a data.
+
+Constants
+> * SYNC_ON : bool `true`
+> * SYNC_OFF : bool `false`
+
+## Events
+
+<a name="onopen"/>
+### On("open")
+
+Attaches "open" event handler. A "open" event is emitted when PeerConnect is ready by `Open()` method.
+
+```c++
+pc.On("open", function_pc( std::string peer ) {
+  // ...
+})
+```
+
+Parameters
+
+> peer : A name of initialized peer
+
+<a name="onclose"/>
+### On("close")
+
+Attaches "close" event handler. A "close" event is emitted when connection is closed.
+
+```c++
+pc.On("close", function_pc( std::string peer, CloseCode code, std::string desc ) {
+  // ...
+})
+```
+
+Parameters
+
+> * peer : A name of closed peer. Note that peer is one of local peer or remote peer.
+> * code : A close code defined in the PeerConnect.
+> * desc : A description of close reason.
+
+Constants
+
+```c++
+enum CloseCode {
+  // Success
+  CLOSE_NORMAL        = 0,
+
+  // Failure
+  CLOSE_GOING_AWAY,
+  CLOSE_ABNORMAL,
+  CLOSE_PROTOCOL_ERROR,
+  CLOSE_SIGNAL_ERROR
+};
+```
+
+<a name="onconnect"/>
+### On("connect")
+
+Attaches "connect" event handler. A "connect" event is emitted when connection is established.
+
+```c++
+pc.On("connect", function_pc( std::string peer ) {
+  // ...
+})
+```
+
+Parameters
+
+> * peer : A name of remote peer
+
+<a name="onmessage"/>
+### On("message")
+
+Attaches "message" event handler. A "message" event is emitted when data is received.
+
+```c++
+pc.On("message", function_pc( std::string peer, char* data, std::size_t size ) {
+  // ...
+})
+```
+
+Parameters
+
+> * peer : A name of remote peer that sent a message.
+> * data : A pointer of data.
+> * size : A size of data.
+
+
+<a name="onwritable"/>
+### On("writable")
+
+Attaches "writable" event handler. A "writable" event is emitted when read to send data. It is useful when asynchronously (SYNC_OFF) sending a data.
+
+```c++
+pc.On("writable", function_pc( std::string peer ){
+  // ...
+});
+```
+
+Parameter
+> * peer : A name of peer that is ready to send a data.
+
+## Static methods
+
+<a name="run"/>
+### PeerConnect::Run()
+
+Run PeerConnect object's event processing loop. Note that the thread quit a loop if other thread calls PeerConnect::Stop() method. 
+
+```c++
+void PeerConnect::Run()
+```
+
+<a name="stop"/>
+### PeerConnect::Stop()
+
+Stop PeerConnect object's event processing loop.
+
+```c++
+void PeerConnect::Stop()
+```
+
+## Example
+
+<a name="echoserver"/>
+* echo server
+
+```c++
+PeerConnect pc("SERVER_PEER");
+
+pc.On("message", function_pc(std::string peer, char* data, std::size_t size) {
+  // Echo message
+  pc.Send(peer, data, size);
+});
+
+pc.Open();
+PeerConnect::Run();
+```
+
+<a name="echoclient"/>
+* echo client
+```c++
+
+PeerConnect pc;
+
+pc.On("open", function_pc(std::string peer) {
+  pc.Connect("SERVER_PEER");
+});
+
+pc.On("connect", function_pc(std::string peer) {
+  pc.Send(peer, "Hello world");
+});
+
+pc.On("close", function_pc(std::string peer, CloseCode code, std::string desc) {
+  PeerConnect::Stop();
+});
+
+pc.On("message", function_pc(std::string peer, char* data, std::size_t size) {
+  pc.Close();
+});
+
+pc.Open();
+PeerConnect::Run();
+```