From 5718fe14b7954476e18d5df9d4cb557daecd4bab Mon Sep 17 00:00:00 2001
From: Arunima Chaudhuri <arunimachaudhuri2020@gmail.com>
Date: Mon, 20 May 2024 14:02:39 +0000
Subject: [PATCH] Gossipsub implementation

Signed-off-by: Arunima Chaudhuri <arunimachaudhuri2020@gmail.com>
---
 DAS/node.py      | 34 +++++++++++++++++++++++++++++++++-
 DAS/simulator.py | 14 +++++++++++++-
 2 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/DAS/node.py b/DAS/node.py
index 85aaf8a..5774242 100644
--- a/DAS/node.py
+++ b/DAS/node.py
@@ -246,6 +246,14 @@ class Node:
             self.statsRxDupInSlot += 1
         self.statsRxInSlot += 1
 
+    def receiveSegmentViaGossip(self, rID, cID):
+        """Receive a segment via gossipsub protocol."""
+        if not self.amImalicious:
+            self.logger.trace("Recv via gossipsub: %d: %d,%d", self.ID, rID, cID, extra=self.format)
+            self.receivedBlock.setSegment(rID, cID)
+            self.sampleRecvCount += 1
+        self.statsRxInSlot += 1
+
     def addToSendQueue(self, rID, cID):
         """Queue a segment for forwarding."""
         if self.perNodeQueue and not self.amImalicious:
@@ -504,7 +512,26 @@ class Node:
             if self.statsTxInSlot >= self.bwUplink:
                 return
 
-    def send(self):
+    def gossipSub(self, rows, cols):
+        """ This function facilitates the Gossipsub protocol for segment distribution among nodes.
+        It ensures that each node receives any missing segments by checking other nodes in the network.
+
+        Args:
+            rows (dict): A hash table where the keys are row IDs and the values are lists of nodes that contain these rows.
+            cols (dict): A hash table where the keys are column IDs and the values are lists of nodes that contain these columns.
+        
+        Description:
+            - The function iterates through all row IDs and column IDs.
+            - For each segment identified by a row ID (rID) and a column ID (cID):
+                - It checks if the current node (self) already has the segment.
+                - If the segment is missing, it attempts to receive the segment from other nodes using the Gossipsub protocol via the receiveSegmentViaGossip method.
+        """
+        for rID in rows:
+            for cID in cols:
+                if not self.receivedBlock.getSegment(rID, cID):
+                    self.receiveSegmentViaGossip(rID, cID)
+    
+    def send(self, rows, cols):
         """ Send as much as we can in the timestep, limited by bwUplink."""
 
         # process node level send queue
@@ -529,6 +556,11 @@ class Node:
             self.runDumbRandomScheduler()
         if self.statsTxInSlot >= self.bwUplink:
             return
+        
+        if not self.amImalicious:
+            self.gossipSub(rows, cols)
+        if self.statsTxInSlot >= self.bwUplink:
+            return
 
     def logRows(self):
         """It logs the rows assigned to the validator."""
diff --git a/DAS/simulator.py b/DAS/simulator.py
index 7d4b341..9aed26d 100644
--- a/DAS/simulator.py
+++ b/DAS/simulator.py
@@ -278,10 +278,22 @@ class Simulator:
             self.logger.debug("Expected Samples: %d" % expected, extra=self.format)
             self.logger.debug("Missing Samples: %d" % missingSamples, extra=self.format)
             oldMissingSamples = missingSamples
+            rows = {}
+            cols = {}
+            for i in range(0, self.shape.numberNodes):
+                if not self.validators[i].amIproposer and not self.validators[i].amImalicious:
+                    for id in self.validators[i].columnIDs:
+                        if id not in cols:
+                            cols[id] = []
+                        cols[id].append(self.validators[i])
+                    for id in self.validators[i].rowIDs:
+                        if id not in rows:
+                            rows[id] = []
+                        rows[id].append(self.validators[i])
             self.logger.debug("PHASE SEND %d" % steps, extra=self.format)
             for i in range(0,self.shape.numberNodes):
                 if not self.validators[i].amImalicious:
-                    self.validators[i].send()
+                    self.validators[i].send(rows, cols)
             self.logger.debug("PHASE RECEIVE %d" % steps, extra=self.format)
             for i in range(1,self.shape.numberNodes):
                 self.validators[i].receiveRowsColumns()