feat(dial): exposing connection handle flow

dryajov · dryajov · commit bb485e1640eb · 2017-04-02T12:43:21.000-07:00
diff --git a/src/dial.js b/src/dial.js
@@ -1,12 +1,9 @@
 'use strict'
 
-const multistream = require('multistream-select')
 const Connection = require('interface-connection').Connection
 const debug = require('debug')
 const log = debug('libp2p:swarm:dial')
 
-const protocolMuxer = require('./protocol-muxer')
-
 module.exports = function dial (swarm) {
   return (pi, protocol, callback) => {
     if (typeof protocol === 'function') {
@@ -17,6 +14,7 @@ module.exports = function dial (swarm) {
     callback = callback || function noop () {}
 
     const proxyConn = new Connection()
+    const connHandler = swarm.connHandler(pi, protocol, proxyConn)
 
     const b58Id = pi.id.toB58String()
     log('dialing %s', b58Id)
@@ -27,54 +25,22 @@ module.exports = function dial (swarm) {
           if (err) {
             return callback(err)
           }
-          gotWarmedUpConn(conn)
+          connHandler.handleNew(conn, callback)
         })
       } else {
         const conn = swarm.conns[b58Id]
         swarm.conns[b58Id] = undefined
-        gotWarmedUpConn(conn)
+        connHandler.handleWarmedUp(conn, callback)
       }
     } else {
       if (!protocol) {
         return callback()
       }
-      gotMuxer(swarm.muxedConns[b58Id].muxer)
+      connHandler.gotMuxer(swarm.muxedConns[b58Id].muxer, callback)
     }
 
     return proxyConn
 
-    function gotWarmedUpConn (conn) {
-      conn.setPeerInfo(pi)
-      attemptMuxerUpgrade(conn, (err, muxer) => {
-        if (!protocol) {
-          if (err) {
-            swarm.conns[b58Id] = conn
-          }
-          return callback()
-        }
-
-        if (err) {
-          // couldn't upgrade to Muxer, it is ok
-          protocolHandshake(conn, protocol, callback)
-        } else {
-          gotMuxer(muxer)
-        }
-      })
-    }
-
-    function gotMuxer (muxer) {
-      if (swarm.identify) {
-        // TODO: Consider:
-        // 1. overload getPeerInfo
-        // 2. exec identify (through getPeerInfo)
-        // 3. update the peerInfo that is already stored in the conn
-      }
-
-      openConnInMuxedConn(muxer, (conn) => {
-        protocolHandshake(conn, protocol, callback)
-      })
-    }
-
     function attemptDial (pi, cb) {
       const tKeys = swarm.availableTransports(pi)
 
@@ -93,106 +59,9 @@ module.exports = function dial (swarm) {
             return nextTransport(tKeys.shift())
           }
 
-          cryptoDial()
-
-          function cryptoDial () {
-            const ms = new multistream.Dialer()
-            ms.handle(conn, (err) => {
-              if (err) {
-                return cb(err)
-              }
-
-              const id = swarm._peerInfo.id
-              log('selecting crypto: %s', swarm.crypto.tag)
-              ms.select(swarm.crypto.tag, (err, conn) => {
-                if (err) {
-                  return cb(err)
-                }
-
-                const wrapped = swarm.crypto.encrypt(id, id.privKey, conn)
-                cb(null, wrapped)
-              })
-            })
-          }
+          cb(null, conn)
         })
       }
     }
-
-    function attemptMuxerUpgrade (conn, cb) {
-      const muxers = Object.keys(swarm.muxers)
-      if (muxers.length === 0) {
-        return cb(new Error('no muxers available'))
-      }
-
-      // 1. try to handshake in one of the muxers available
-      // 2. if succeeds
-      //  - add the muxedConn to the list of muxedConns
-      //  - add incomming new streams to connHandler
-
-      const ms = new multistream.Dialer()
-      ms.handle(conn, (err) => {
-        if (err) {
-          return callback(new Error('multistream not supported'))
-        }
-
-        nextMuxer(muxers.shift())
-      })
-
-      function nextMuxer (key) {
-        log('selecting %s', key)
-        ms.select(key, (err, conn) => {
-          if (err) {
-            if (muxers.length === 0) {
-              cb(new Error('could not upgrade to stream muxing'))
-            } else {
-              nextMuxer(muxers.shift())
-            }
-            return
-          }
-
-          const muxedConn = swarm.muxers[key].dialer(conn)
-          swarm.muxedConns[b58Id] = {}
-          swarm.muxedConns[b58Id].muxer = muxedConn
-          // should not be needed anymore - swarm.muxedConns[b58Id].conn = conn
-
-          swarm.emit('peer-mux-established', pi)
-
-          muxedConn.once('close', () => {
-            const b58Str = pi.id.toB58String()
-            delete swarm.muxedConns[b58Str]
-            pi.disconnect()
-            swarm._peerBook.get(b58Str).disconnect()
-            swarm.emit('peer-mux-closed', pi)
-          })
-
-          // For incoming streams, in case identify is on
-          muxedConn.on('stream', (conn) => {
-            protocolMuxer(swarm.protocols, conn)
-          })
-
-          cb(null, muxedConn)
-        })
-      }
-    }
-
-    function openConnInMuxedConn (muxer, cb) {
-      cb(muxer.newStream())
-    }
-
-    function protocolHandshake (conn, protocol, cb) {
-      const ms = new multistream.Dialer()
-      ms.handle(conn, (err) => {
-        if (err) {
-          return callback(err)
-        }
-        ms.select(protocol, (err, conn) => {
-          if (err) {
-            return callback(err)
-          }
-          proxyConn.setInnerConn(conn)
-          callback(null, proxyConn)
-        })
-      })
-    }
   }
 }
diff --git a/src/handler.js b/src/handler.js
@@ -0,0 +1,162 @@
+'use strict'
+
+const multistream = require('multistream-select')
+const protocolMuxer = require('./protocol-muxer')
+
+const debug = require('debug')
+const log = debug('libp2p:swarm:handle')
+
+module.exports = function process (swarm) {
+  return (pi, protocol, proxyConn) => {
+    const b58Id = pi.id.toB58String()
+
+    function cryptoDial (conn, cb) {
+      const ms = new multistream.Dialer()
+      ms.handle(conn, (err) => {
+        if (err) {
+          return cb(err)
+        }
+
+        const id = swarm._peerInfo.id
+        log('selecting crypto: %s', swarm.crypto.tag)
+        ms.select(swarm.crypto.tag, (err, conn) => {
+          if (err) {
+            return cb(err)
+          }
+
+          const wrapped = swarm.crypto.encrypt(id, id.privKey, conn)
+          cb(null, wrapped)
+        })
+      })
+    }
+
+    function gotWarmedUpConn (conn, cb) {
+      conn.setPeerInfo(pi)
+      attemptMuxerUpgrade(conn, (err, muxer) => {
+        if (!protocol) {
+          if (err) {
+            swarm.conns[b58Id] = conn
+          }
+          return cb()
+        }
+
+        if (err) {
+          // couldn't upgrade to Muxer, it is ok
+          protocolHandshake(conn, protocol, cb)
+        } else {
+          gotMuxer(muxer, cb)
+        }
+      })
+    }
+
+    function attemptMuxerUpgrade (conn, cb) {
+      const muxers = Object.keys(swarm.muxers)
+      if (muxers.length === 0) {
+        return cb(new Error('no muxers available'))
+      }
+
+      // 1. try to handshake in one of the muxers available
+      // 2. if succeeds
+      //  - add the muxedConn to the list of muxedConns
+      //  - add incomming new streams to connHandler
+
+      const ms = new multistream.Dialer()
+      ms.handle(conn, (err) => {
+        if (err) {
+          return cb(new Error('multistream not supported'))
+        }
+
+        nextMuxer(muxers.shift())
+      })
+
+      function nextMuxer (key) {
+        log('selecting %s', key)
+        ms.select(key, (err, conn) => {
+          if (err) {
+            if (muxers.length === 0) {
+              cb(new Error('could not upgrade to stream muxing'))
+            } else {
+              nextMuxer(muxers.shift())
+            }
+            return
+          }
+
+          const muxedConn = swarm.muxers[key].dialer(conn)
+          swarm.muxedConns[b58Id] = {}
+          swarm.muxedConns[b58Id].muxer = muxedConn
+          // should not be needed anymore - swarm.muxedConns[b58Id].conn = conn
+
+          swarm.emit('peer-mux-established', pi)
+
+          muxedConn.once('close', () => {
+            const b58Str = pi.id.toB58String()
+            delete swarm.muxedConns[b58Str]
+            pi.disconnect()
+            swarm._peerBook.get(b58Str).disconnect()
+            swarm.emit('peer-mux-closed', pi)
+          })
+
+          // For incoming streams, in case identify is on
+          muxedConn.on('stream', (conn) => {
+            protocolMuxer(swarm.protocols, conn)
+          })
+
+          cb(null, muxedConn)
+        })
+      }
+    }
+
+    function openConnInMuxedConn (muxer, cb) {
+      cb(muxer.newStream())
+    }
+
+    function protocolHandshake (conn, protocol, cb) {
+      const ms = new multistream.Dialer()
+      ms.handle(conn, (err) => {
+        if (err) {
+          return cb(err)
+        }
+        ms.select(protocol, (err, conn) => {
+          if (err) {
+            return cb(err)
+          }
+          proxyConn.setInnerConn(conn)
+          cb(null, proxyConn)
+        })
+      })
+    }
+
+    function handleNew (conn, cb) {
+      cryptoDial(conn, (err, conn) => {
+        if (err) {
+          log(err)
+          return cb(err)
+        }
+        gotWarmedUpConn(conn, cb)
+      })
+    }
+
+    function handleWarmedUp (conn, cb) {
+      gotWarmedUpConn(conn, cb)
+    }
+
+    function gotMuxer (muxer, cb) {
+      if (swarm.identify) {
+        // TODO: Consider:
+        // 1. overload getPeerInfo
+        // 2. exec identify (through getPeerInfo)
+        // 3. update the peerInfo that is already stored in the conn
+      }
+
+      openConnInMuxedConn(muxer, (conn) => {
+        protocolHandshake(conn, protocol, cb)
+      })
+    }
+
+    return {
+      handleNew: handleNew,
+      handleWarmedUp: handleWarmedUp,
+      gotMuxer: gotMuxer
+    }
+  }
+}
diff --git a/src/index.js b/src/index.js
@@ -6,6 +6,7 @@ const each = require('async/each')
 const series = require('async/series')
 const transport = require('./transport')
 const connection = require('./connection')
+const handler = require('./handler')
 const dial = require('./dial')
 const protocolMuxer = require('./protocol-muxer')
 const plaintext = require('./plaintext')
@@ -56,6 +57,7 @@ function Swarm (peerInfo, peerBook) {
 
   this.transport = transport(this)
   this.connection = connection(this)
+  this.connHandler = handler(this)
 
   this.availableTransports = (pi) => {
     const myAddrs = pi.multiaddrs.toArray()
diff --git a/src/transport.js b/src/transport.js
