From 9db53a6fb1c3dc0e6112022ac4140fe0dc0c2c67 Mon Sep 17 00:00:00 2001
From: Robert Zajac <rzajac@seas.upenn.edu>
Date: Sun, 21 Oct 2018 15:19:22 -0400
Subject: [PATCH] Adding new methods to multiaddr and commenting

---
 network/multiaddr.py | 44 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 43 insertions(+), 1 deletion(-)

diff --git a/network/multiaddr.py b/network/multiaddr.py
index e6d4a5c..d5de3e0 100644
--- a/network/multiaddr.py
+++ b/network/multiaddr.py
@@ -1,6 +1,12 @@
 class Multiaddr:
 
+    # Validates input string and constructs internal representation.
     def __init__(self, addr):
+        # Empty multiaddrs are valid.
+        if not addr:
+            self.protocol_map = dict()
+            return
+
         if not addr[0] == "/":
             raise MultiaddrValueError("Invalid input multiaddr.")
 
@@ -22,17 +28,53 @@ class Multiaddr:
             is_protocol = not is_protocol
 
         self.protocol_map = protocol_map
-        self.addr = addr
 
     def get_protocols(self):
+        """
+        :return: List of protocols contained in this multiaddr.
+        """
         return list(self.protocol_map.keys())
 
     def get_protocol_value(self, protocol):
+        """
+        Getter for protocol values in this multiaddr.
+        :param protocol: the protocol whose value to retrieve
+        :return: value of input protocol
+        """
         if protocol not in self.protocol_map:
             return None
 
         return self.protocol_map[protocol]
 
+    def add_protocol(self, protocol, value):
+        """
+        Setter for protocol values in this multiaddr.
+        :param protocol: the protocol whose value to set or add
+        :param value: the value for the input protocol
+        :return: True if successful
+        """
+        self.protocol_map[protocol] = value
+        return True
+
+    def remove_protocol(self, protocol):
+        """
+        Remove protocol and its value from this multiaddr.
+        :param protocol: the protocol to remove
+        :return: True if remove succeeded, False if protocol was not contained in this multiaddr
+        """
+        del self.protocol_map[protocol]
+
+    def get_multiaddr_string(self):
+        """
+        :return: the string representation of this multiaddr.
+        """
+        addr = ""
+
+        for protocol in self.protocol_map:
+            addr += "/" + protocol + "/" + self.get_protocol_value(protocol)
+
+        return addr
+
 
 class MultiaddrValueError(ValueError):
     """Raised when the input string to the Multiaddr constructor was invalid."""