From 4c16cc3c4da7bbf8375d7951185db1761eb396bf Mon Sep 17 00:00:00 2001 From: Paul Buetow Date: Sun, 22 Jun 2025 16:45:17 +0300 Subject: Remove all Raft protocol code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Removed all Raft-related code as it was not working properly: - Removed VSRaftProtocol.java implementation - Removed all Raft test files - Removed Raft example/demo files - Removed Raft documentation - Removed Raft simulation files (.dat) - Removed Raft scripts - Updated VSRegisteredEvents to remove Raft registration - Updated SimulationBuilder to remove RAFT constant - Updated SimulationFactory to remove Raft methods - Updated SimulationBuilderTest to remove Raft tests - Updated pom.xml to remove Raft test configurations The protocol had issues with leader election not completing in GUI mode. šŸ¤– Generated with Claude Code https://claude.ai/code Co-Authored-By: Claude --- CreateRaftSimulationDirect.java | 36 -- RAFT_TESTING.md | 68 --- docs/creating-raft-simulation.md | 99 ---- docs/raft-simulation-status.md | 115 ---- pom.xml | 8 +- saved-simulations/README-raft.md | 129 ----- saved-simulations/raft-debug.dat | Bin 13754 -> 0 bytes saved-simulations/raft-fault-tolerant.dat | Bin 18305 -> 0 bytes saved-simulations/raft-with-clients.dat | Bin 16754 -> 0 bytes saved-simulations/raft.dat | Bin 13759 -> 0 bytes scripts/analyze-raft-simulation.sh | 57 -- scripts/create-raft-simulation.sh | 74 --- src/main/java/events/VSRegisteredEvents.java | 1 - .../examples/CreateAndVerifyRaftSimulation.java | 142 ----- .../java/examples/CreateMinimalRaftSimulation.java | 86 --- .../java/examples/CreateSimpleRaftSimulation.java | 123 ----- .../java/examples/CreateWorkingRaftSimulation.java | 152 ------ src/main/java/examples/RaftSimulationBuilder.java | 76 --- src/main/java/examples/TestRaftLoading.java | 57 -- .../protocols/implementations/VSRaftProtocol.java | 603 --------------------- .../java/simulator/builder/SimulationBuilder.java | 1 - .../java/simulator/builder/SimulationFactory.java | 32 -- .../implementations/VSRaftProtocolTest.java | 308 ----------- src/test/java/simulator/SimpleRaftGUITest.java | 66 --- .../simulator/builder/SimulationBuilderTest.java | 44 +- src/test/java/testing/RaftSimulationTest.java | 57 -- .../java/testing/protocols/RaftProtocolTest.java | 77 --- 27 files changed, 3 insertions(+), 2408 deletions(-) delete mode 100644 CreateRaftSimulationDirect.java delete mode 100644 RAFT_TESTING.md delete mode 100644 docs/creating-raft-simulation.md delete mode 100644 docs/raft-simulation-status.md delete mode 100644 saved-simulations/README-raft.md delete mode 100644 saved-simulations/raft-debug.dat delete mode 100644 saved-simulations/raft-fault-tolerant.dat delete mode 100644 saved-simulations/raft-with-clients.dat delete mode 100644 saved-simulations/raft.dat delete mode 100755 scripts/analyze-raft-simulation.sh delete mode 100755 scripts/create-raft-simulation.sh delete mode 100644 src/main/java/examples/CreateAndVerifyRaftSimulation.java delete mode 100644 src/main/java/examples/CreateMinimalRaftSimulation.java delete mode 100644 src/main/java/examples/CreateSimpleRaftSimulation.java delete mode 100644 src/main/java/examples/CreateWorkingRaftSimulation.java delete mode 100644 src/main/java/examples/RaftSimulationBuilder.java delete mode 100644 src/main/java/examples/TestRaftLoading.java delete mode 100644 src/main/java/protocols/implementations/VSRaftProtocol.java delete mode 100644 src/test/java/protocols/implementations/VSRaftProtocolTest.java delete mode 100644 src/test/java/simulator/SimpleRaftGUITest.java delete mode 100644 src/test/java/testing/RaftSimulationTest.java delete mode 100644 src/test/java/testing/protocols/RaftProtocolTest.java diff --git a/CreateRaftSimulationDirect.java b/CreateRaftSimulationDirect.java deleted file mode 100644 index ec4712d..0000000 --- a/CreateRaftSimulationDirect.java +++ /dev/null @@ -1,36 +0,0 @@ -import simulator.*; -import core.*; -import prefs.*; -import events.VSRegisteredEvents; -import events.internal.VSProtocolEvent; -import serialize.VSSerialize; -import java.io.*; - -public class CreateRaftSimulationDirect { - public static void main(String[] args) { - try { - // 1. Create a basic simulation with the GUI to get proper structure - System.out.println("Creating Raft simulation..."); - System.out.println("Note: This requires manual intervention:"); - System.out.println("1. Run DS-Sim GUI: java -jar target/ds-sim-1.0.1-SNAPSHOT.jar"); - System.out.println("2. Add 3 processes"); - System.out.println("3. Right-click each process and select 'Raft Consensus' as Server"); - System.out.println("4. Save as 'saved-simulations/raft.dat'"); - System.out.println("5. Close the GUI"); - - // For now, let's copy and modify an existing simulation - // We'll use the basic structure from ping-pong but change the protocol - - // Read ping-pong simulation - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - System.out.println("\nAlternatively, you can run this test with the included test simulation:"); - System.out.println("java -cp target/classes:target/test-classes -Djava.awt.headless=true -Dds.sim.verbose=true testing.HeadlessProtocolRunner saved-simulations/raft.dat"); - - } catch (Exception e) { - e.printStackTrace(); - } - } -} \ No newline at end of file diff --git a/RAFT_TESTING.md b/RAFT_TESTING.md deleted file mode 100644 index 29a0fba..0000000 --- a/RAFT_TESTING.md +++ /dev/null @@ -1,68 +0,0 @@ -# Raft Simulation Testing Guide - -## What We Fixed - -The Raft simulation wasn't working because of a fundamental design issue with how protocols are activated: - -1. **Protocol Activation Mismatch**: The Raft protocol uses `HAS_ON_SERVER_START` which means only servers have their `onServerStart()` method called when activated. However, it also implemented `onClientStart()` which would NEVER be called due to the flag setting. - -2. **Client Communication**: Since clients never had their start method called, they never initiated any communication. We fixed this by having clients react to server heartbeats instead. - -## Changes Made - -1. Modified `VSRaftProtocol.java`: - - Clients now react to `APPEND_ENTRIES` (heartbeat) messages from servers - - When a client receives its first heartbeat, it schedules its first request - - Client state is now tracked with simple instance variables instead of trying to use VSPrefs methods with default values - -## How to Test the Raft Simulation - -1. **Build the project**: - ```bash - mvn clean package - ``` - -2. **Create/Update the simulation**: - ```bash - java -cp target/ds-sim-1.0.1-SNAPSHOT.jar examples.RaftSimulationBuilder - ``` - -3. **Run the simulator GUI**: - ```bash - java -jar target/ds-sim-1.0.1-SNAPSHOT.jar - ``` - -4. **Load and run the simulation**: - - Click File ā†’ Open - - Navigate to `saved-simulations/raft-consensus.dat` - - Click the Play button to start the simulation - - You should see: - - Servers (processes 0-1) starting elections - - One server becoming the leader (highlighted) - - The leader sending heartbeats to all processes - - The client (process 2) receiving heartbeats and sending requests - - Log entries being replicated across servers - -## Expected Behavior - -1. **Initial State**: All servers start as FOLLOWERS -2. **Election**: After election timeout, followers become CANDIDATES and request votes -3. **Leader Election**: The first candidate to get majority votes becomes LEADER -4. **Heartbeats**: The leader sends periodic heartbeats to maintain authority -5. **Client Requests**: Clients send requests after receiving heartbeats from the leader -6. **Log Replication**: The leader replicates client commands to all followers - -## Key Insights - -- The simulator uses an event-driven architecture where protocols must be explicitly activated -- Protocols with `HAS_ON_SERVER_START` only trigger `onServerStart()` for servers -- Protocols with `HAS_ON_CLIENT_START` only trigger `onClientStart()` for clients -- Client-server communication often needs to be initiated by one side (usually the side that has the start method called) - -## Debugging Tips - -If the simulation doesn't work as expected: -1. Check the console output for any error messages -2. Verify that all 3 processes are created (0-1 as servers, 2 as client) -3. Ensure the protocol activations are scheduled at the right times -4. Look for the election timeout messages and leader elections in the logs \ No newline at end of file diff --git a/docs/creating-raft-simulation.md b/docs/creating-raft-simulation.md deleted file mode 100644 index d3fb9ab..0000000 --- a/docs/creating-raft-simulation.md +++ /dev/null @@ -1,99 +0,0 @@ -# Creating a Raft Consensus Simulation - -This guide explains how to create a working Raft consensus simulation in DS-Sim. - -## Overview - -The Raft protocol implementation in DS-Sim demonstrates: -- Leader election with randomized timeouts -- Heartbeat messages from leader to followers -- Vote requests and responses -- Term management -- Log replication (basic implementation) - -## Creating the Simulation via GUI - -1. **Start DS-Sim**: - ```bash - java -jar target/ds-sim-1.0.1-SNAPSHOT.jar - ``` - -2. **Add Processes**: - - Click "Add Process" button 3 times to create 3 nodes - - This creates the minimum cluster size for consensus - -3. **Configure Each Process as Raft Server**: - - Right-click on Process 1 - - Select "Protocols" ā†’ "Raft Consensus Algorithm" ā†’ "Server" - - Repeat for Process 2 and Process 3 - -4. **Set Simulation Duration**: - - Go to Edit ā†’ Preferences ā†’ Simulator - - Set "Simulation duration" to 15 seconds - - This gives enough time to see leader election - -5. **Save the Simulation**: - - File ā†’ Save As - - Save as `saved-simulations/raft.dat` - -6. **Run the Simulation**: - - Click the "Play" button - - Watch the message exchanges and leader election - -## Expected Behavior - -When you run the simulation: - -1. **Initial State** (0-300ms): - - All nodes start as FOLLOWERS - - Each sets a random election timeout (150-300ms) - -2. **Election Phase** (150-500ms): - - First node to timeout becomes CANDIDATE - - Sends REQUEST_VOTE messages to all nodes - - Other nodes respond with VOTE_RESPONSE - -3. **Leader Establishment** (300-600ms): - - Candidate with majority votes becomes LEADER - - Leader is highlighted in the visualization - - Starts sending APPEND_ENTRIES (heartbeats) - -4. **Steady State** (600ms+): - - Leader sends periodic heartbeats (every 50ms) - - Followers reset election timeout on heartbeat - - System remains stable with one leader - -## Testing the Simulation - -Run the simulation in headless mode: -```bash -java -cp target/classes:target/test-classes \ - -Djava.awt.headless=true \ - -Dds.sim.verbose=true \ - testing.HeadlessProtocolRunner saved-simulations/raft.dat -``` - -Expected output includes: -- "[FOLLOWER T:0 N:X] Raft node initialized as FOLLOWER" -- "[CANDIDATE T:1 N:X] Starting election for term 1" -- "Sending vote request to all nodes" -- "[FOLLOWER T:1 N:Y] Granted vote to node X for term 1" -- "[LEADER T:1 N:X] Elected as leader with Y votes" -- "Sending heartbeats to all followers" - -## Troubleshooting - -If leader election doesn't occur: -- Ensure all processes are configured as "Server" not "Client" -- Check that simulation duration is long enough (>5 seconds) -- Verify VSRaftProtocol has `setClassname()` in constructor - -## Implementation Notes - -The Raft protocol uses: -- `onServerStart()`: Initializes election timeout -- `onServerSchedule()`: Handles timeouts and periodic tasks -- `scheduleAt()`: Schedules future events -- `sendMessage()`: Broadcasts to all other nodes - -See `VSRaftProtocol.java` for full implementation details. \ No newline at end of file diff --git a/docs/raft-simulation-status.md b/docs/raft-simulation-status.md deleted file mode 100644 index 146c11c..0000000 --- a/docs/raft-simulation-status.md +++ /dev/null @@ -1,115 +0,0 @@ -# Raft Simulation Status Report - -## Completed Tasks - -### 1. Raft Protocol Documentation āœ“ -- Created comprehensive documentation at `/docs/raft-consensus-protocol.md` -- Includes detailed explanations of: - - Leader election process - - Log replication mechanism - - Safety properties - - ASCII diagrams for visualization - - Implementation notes for DS-Sim - -### 2. Raft Protocol Implementation āœ“ -- Successfully implemented in `VSRaftProtocol.java` -- Features include: - - Leader election with randomized timeouts - - Heartbeat mechanism - - Log replication - - Client request handling - - Crash recovery support - -### 3. Simulation Creation āœ“ -- Created multiple simulation files: - - `saved-simulations/raft-working.dat` - Full working simulation - - `saved-simulations/raft-consensus.dat` - Basic consensus demo - - `saved-simulations/raft-simple.dat` - Simple example - - `saved-simulations/raft-verified.dat` - Verification attempt - -### 4. Example Programs āœ“ -- `CreateWorkingRaftSimulation.java` - Creates a comprehensive Raft simulation -- `CreateAndVerifyRaftSimulation.java` - Creates and attempts to verify -- `CreateMinimalRaftSimulation.java` - Minimal test case -- `TestRaftLoading.java` - Verifies Raft protocol registration - -## Current Issue - -### Protocol Deserialization Error -When loading saved simulations, the following error occurs: -``` -java.lang.NullPointerException: Cannot invoke "protocols.VSAbstractProtocol.deserialize()" -because "protocol" is null -``` - -### Root Cause Analysis -1. The serialization process saves ALL protocols that have been instantiated on a process -2. During deserialization, it tries to recreate these protocol instances -3. Some protocols may not have been properly initialized or registered -4. The error suggests that a protocol classname is null or empty during deserialization - -### Workaround -Despite the deserialization error, the simulation files are created successfully and contain: -- 5 processes (3 servers, 2 clients) -- Raft protocol activations scheduled at appropriate times -- Crash/recovery events for testing fault tolerance - -## How to Use the Raft Simulation - -1. **Run the simulator GUI:** - ```bash - java -jar target/ds-sim-1.0.1-SNAPSHOT.jar - ``` - -2. **Load the simulation:** - - File ā†’ Open ā†’ `saved-simulations/raft-working.dat` - - Note: You may see deserialization warnings, but the simulation should still load - -3. **Run the simulation:** - - Click the Run (ā–¶) button - - Watch for: - - Leader election messages (REQUEST_VOTE, VOTE_RESPONSE) - - Heartbeats from the leader (APPEND_ENTRIES) - - Client requests and responses - - Re-election when servers crash - -## Testing Framework - -### Attempted Approaches -1. **GUI Testing Framework** - Created test classes to verify simulation behavior -2. **Integration Tests** - Direct testing without GUI -3. **Verification Programs** - Standalone verification utilities - -### Current Status -The testing frameworks encounter compilation issues due to: -- Private field access requirements -- Missing or changed API methods -- Type compatibility issues - -## Recommendations - -1. **For immediate use:** The created simulations should work when loaded in the GUI despite the warnings -2. **For fixing deserialization:** Investigate why some protocols have null classnames during save/load -3. **For testing:** Consider using the GUI directly to verify behavior rather than automated tests - -## Files Created - -### Documentation -- `/docs/raft-consensus-protocol.md` - Complete Raft protocol documentation -- `/docs/raft-simulation-status.md` - This status report -- `/saved-simulations/README-raft.txt` - User instructions - -### Source Code -- `/src/main/java/examples/CreateWorkingRaftSimulation.java` -- `/src/main/java/examples/CreateAndVerifyRaftSimulation.java` -- `/src/main/java/examples/CreateMinimalRaftSimulation.java` -- `/src/main/java/examples/TestRaftLoading.java` - -### Simulation Files -- `/saved-simulations/raft-working.dat` -- `/saved-simulations/raft-consensus.dat` -- `/saved-simulations/raft-simple.dat` -- `/saved-simulations/raft-verified.dat` - -### Test Files -- `/src/test/java/simulator/SimpleRaftGUITest.java` \ No newline at end of file diff --git a/pom.xml b/pom.xml index e0f8035..b1e1043 100644 --- a/pom.xml +++ b/pom.xml @@ -88,11 +88,9 @@ **/events/**/*Test.java **/protocols/VSAbstractProtocolTest.java **/protocols/implementations/VSPingPongProtocolTest.java - **/protocols/implementations/VSRaftProtocolTest.java - **/SimpleRaftGUITest.java **/testing/**/*Test.java @@ -198,11 +196,9 @@ **/events/*Test.java **/protocols/VSAbstractProtocolTest.java **/protocols/implementations/VSPingPongProtocolTest.java - **/protocols/implementations/VSRaftProtocolTest.java - + - **/SimpleRaftGUITest.java - **/testing/**/*Test.java + **/testing/**/*Test.java diff --git a/saved-simulations/README-raft.md b/saved-simulations/README-raft.md deleted file mode 100644 index a9d3e83..0000000 --- a/saved-simulations/README-raft.md +++ /dev/null @@ -1,129 +0,0 @@ -# Raft Consensus Simulation - -## Current Status - -The `raft.dat` file exists but is currently a copy of `ping-pong.dat` and needs to be properly configured with Raft protocol events through the GUI. - -## Why Manual Configuration is Required - -The simulation files use Java's native object serialization format which includes: -- Complex object graphs with circular references -- Private field serialization requiring specific class versions -- GUI-dependent initialization sequences -- Protocol activation through VSProtocolEvent objects - -Programmatic creation attempts failed because: -1. VSSerialize methods require GUI components -2. VSSimulatorVisualization has private methods for process creation -3. The serialization format includes UI state and preferences - -## How to Create a Working Raft Simulation - -### Step 1: Start DS-Sim -```bash -java -jar target/ds-sim-1.0.1-SNAPSHOT.jar -``` - -### Step 2: Create New Simulation -- File ā†’ New (or Ctrl+N) -- This creates a blank simulation - -### Step 3: Add Processes -- Click "Add Process" button 3 times -- This creates a 3-node Raft cluster - -### Step 4: Configure Each Process as Raft Server -For each process (Process 1, 2, and 3): -- Right-click on the process -- Select "Protocols" ā†’ "Raft Consensus Algorithm" ā†’ "Server" -- You'll see a protocol activation event added to the task list - -### Step 5: Set Simulation Duration -- Edit ā†’ Preferences ā†’ Simulator -- Set "Simulation duration" to 15000 (15 seconds) -- Click OK - -### Step 6: Save the Simulation -- File ā†’ Save As -- Navigate to `saved-simulations/` -- Save as `raft.dat` - -### Step 7: Run the Simulation -- Click the Play button (ā–¶) -- Watch the leader election process - -## Expected Behavior - -### Time 0-300ms: Initial State -- All nodes start as FOLLOWERS -- Each sets a random election timeout (150-300ms) -- Status: "FOLLOWER" shown in logs - -### Time 150-500ms: Election Phase -- First node to timeout transitions to CANDIDATE -- Increments term to 1 -- Sends REQUEST_VOTE messages to all other nodes -- Other nodes respond with VOTE_RESPONSE messages - -### Time 300-600ms: Leader Establishment -- Candidate receiving majority votes becomes LEADER -- Leader node is highlighted in the visualization -- Begins sending APPEND_ENTRIES (heartbeat) messages - -### Time 600ms+: Steady State -- Leader sends heartbeats every 50ms -- Followers acknowledge with APPEND_RESPONSE -- If leader fails, new election begins after timeout - -## Verification - -### GUI Verification -1. Run the simulation and observe: - - REQUEST_VOTE messages during election - - One node becoming highlighted (leader) - - Regular APPEND_ENTRIES messages from leader - -### Headless Verification -```bash -java -cp target/classes:target/test-classes \ - -Djava.awt.headless=true \ - -Dds.sim.verbose=true \ - testing.HeadlessProtocolRunner saved-simulations/raft.dat -``` - -Look for these log messages: -- `[FOLLOWER T:0 N:X] Raft node initialized as FOLLOWER` -- `[CANDIDATE T:1 N:X] Starting election for term 1` -- `[LEADER T:1 N:X] Elected as leader with Y votes` - -## Implementation Details - -The Raft protocol implementation (`VSRaftProtocol.java`) includes: - -- **State Machine**: FOLLOWER ā†’ CANDIDATE ā†’ LEADER transitions -- **Election Timeout**: Random 150-300ms to prevent split votes -- **Heartbeat Interval**: 50ms from leader to maintain authority -- **Term Management**: Monotonically increasing terms for safety -- **Vote Tracking**: Majority (n/2 + 1) required for leadership -- **Message Types**: - - REQUEST_VOTE: Candidate requests votes - - VOTE_RESPONSE: Follower grants/denies vote - - APPEND_ENTRIES: Leader heartbeat/log replication - - APPEND_RESPONSE: Follower acknowledgment - -## Troubleshooting - -If the simulation shows no Raft activity: -1. Verify all processes have Raft protocol events in task list -2. Check that events are scheduled at time 0 -3. Ensure simulation duration is > 5 seconds -4. Confirm VSRaftProtocol has `setClassname()` in constructor - -If you see PingPong messages instead of Raft: -- The file wasn't properly recreated -- Delete raft.dat and create from scratch via GUI - -## Scripts - -- `scripts/create-raft-simulation.sh` - Creates template and instructions -- `scripts/analyze-raft-simulation.sh` - Diagnoses simulation issues \ No newline at end of file diff --git a/saved-simulations/raft-debug.dat b/saved-simulations/raft-debug.dat deleted file mode 100644 index 406daf2..0000000 Binary files a/saved-simulations/raft-debug.dat and /dev/null differ diff --git a/saved-simulations/raft-fault-tolerant.dat b/saved-simulations/raft-fault-tolerant.dat deleted file mode 100644 index c2981d9..0000000 Binary files a/saved-simulations/raft-fault-tolerant.dat and /dev/null differ diff --git a/saved-simulations/raft-with-clients.dat b/saved-simulations/raft-with-clients.dat deleted file mode 100644 index a7c579e..0000000 Binary files a/saved-simulations/raft-with-clients.dat and /dev/null differ diff --git a/saved-simulations/raft.dat b/saved-simulations/raft.dat deleted file mode 100644 index f87edd8..0000000 Binary files a/saved-simulations/raft.dat and /dev/null differ diff --git a/scripts/analyze-raft-simulation.sh b/scripts/analyze-raft-simulation.sh deleted file mode 100755 index 7d6d222..0000000 --- a/scripts/analyze-raft-simulation.sh +++ /dev/null @@ -1,57 +0,0 @@ -#!/bin/bash -# -# Analyze why raft.dat isn't working properly -# - -echo "=== Analyzing Raft Simulation Issue ===" -echo - -# Check current raft.dat content -echo "1. Checking raft.dat file..." -if [ -f "saved-simulations/raft.dat" ]; then - echo " āœ“ raft.dat exists ($(stat -c%s saved-simulations/raft.dat 2>/dev/null || stat -f%z saved-simulations/raft.dat) bytes)" - - # Try to detect protocol in the file - echo - echo "2. Detecting protocols in raft.dat..." - strings saved-simulations/raft.dat | grep -E "(Protocol|protocol)" | sort | uniq | head -10 -else - echo " āœ— raft.dat not found!" - exit 1 -fi - -echo -echo "3. Running raft.dat simulation test..." -echo " (Looking for Raft-specific messages)" -echo - -# Run and check for Raft messages -java -cp target/classes:target/test-classes \ - -Djava.awt.headless=true \ - -Dds.sim.verbose=true \ - testing.HeadlessProtocolRunner saved-simulations/raft.dat 2>&1 | \ - grep -E "(FOLLOWER|CANDIDATE|LEADER|REQUEST_VOTE|election|Raft)" | head -20 - -echo -echo "=== Analysis Results ===" -echo -echo "PROBLEM: The raft.dat file contains Ping-Pong protocol events, not Raft protocol." -echo -echo "The file shows these protocols being loaded:" -strings saved-simulations/raft.dat | grep -E "VSPingPongProtocol|VSRaftProtocol" | head -5 - -echo -echo "=== Solution ===" -echo -echo "The raft.dat file needs to be recreated with Raft protocol events." -echo "Since the file uses Java serialization, it must be created via the GUI:" -echo -echo "1. Run: java -jar target/ds-sim-1.0.1-SNAPSHOT.jar" -echo "2. Create a new simulation (File ā†’ New)" -echo "3. Add 3 processes" -echo "4. For each process:" -echo " - Right-click ā†’ Protocols ā†’ Raft Consensus Algorithm ā†’ Server" -echo "5. Save as: saved-simulations/raft.dat" -echo -echo "The issue is that the current raft.dat is just a copy of ping-pong.dat" -echo "and still contains PingPong protocol activation events." \ No newline at end of file diff --git a/scripts/create-raft-simulation.sh b/scripts/create-raft-simulation.sh deleted file mode 100755 index e133ce7..0000000 --- a/scripts/create-raft-simulation.sh +++ /dev/null @@ -1,74 +0,0 @@ -#!/bin/bash -# -# Create and verify a Raft consensus simulation for DS-Sim -# - -echo "=== DS-Sim Raft Simulation Creator ===" -echo - -# Check if we're in the right directory -if [ ! -f "pom.xml" ]; then - echo "Error: Must be run from the DS-Sim root directory" - exit 1 -fi - -# Check if the application is built -if [ ! -f "target/ds-sim-1.0.1-SNAPSHOT.jar" ]; then - echo "Error: Application not built. Run 'mvn clean package' first" - exit 1 -fi - -# Create the raft.dat file from template -if [ -f "saved-simulations/ping-pong.dat" ]; then - cp "saved-simulations/ping-pong.dat" "saved-simulations/raft.dat" - echo "āœ“ Created saved-simulations/raft.dat from template" -else - echo "āœ— Error: Could not find ping-pong.dat template" - exit 1 -fi - -# Create a verification script -cat > verify-raft.sh << 'EOF' -#!/bin/bash -echo "Verifying Raft simulation..." -if [ -f "saved-simulations/raft.dat" ]; then - echo "āœ“ raft.dat exists" - ls -lh saved-simulations/raft.dat -else - echo "āœ— raft.dat not found" -fi -EOF -chmod +x verify-raft.sh - -echo -echo "=== MANUAL STEPS REQUIRED ===" -echo -echo "The raft.dat file has been created but needs manual configuration." -echo "Please follow these steps:" -echo -echo "1. Start DS-Sim:" -echo " java -jar target/ds-sim-1.0.1-SNAPSHOT.jar" -echo -echo "2. Open the template:" -echo " File ā†’ Open ā†’ saved-simulations/raft.dat" -echo -echo "3. Configure for Raft (IMPORTANT - do all steps):" -echo " a) Delete existing protocol events in the task list" -echo " b) Right-click Process 1 ā†’ Protocols ā†’ Raft Consensus Algorithm ā†’ Server" -echo " c) Right-click Process 2 ā†’ Protocols ā†’ Raft Consensus Algorithm ā†’ Server" -echo " d) Right-click Process 3 ā†’ Protocols ā†’ Raft Consensus Algorithm ā†’ Server" -echo -echo "4. Save the file:" -echo " File ā†’ Save" -echo -echo "5. Test the simulation:" -echo " Click the Play button to see leader election" -echo -echo "=== EXPECTED BEHAVIOR ===" -echo "- All nodes start as FOLLOWERS" -echo "- First node to timeout (150-300ms) becomes CANDIDATE" -echo "- CANDIDATE requests votes from other nodes" -echo "- Node with majority votes becomes LEADER (highlighted)" -echo "- LEADER sends heartbeats every 50ms" -echo -echo "To verify after configuration: ./verify-raft.sh" \ No newline at end of file diff --git a/src/main/java/events/VSRegisteredEvents.java b/src/main/java/events/VSRegisteredEvents.java index 91000bc..92deeb0 100644 --- a/src/main/java/events/VSRegisteredEvents.java +++ b/src/main/java/events/VSRegisteredEvents.java @@ -99,7 +99,6 @@ public final class VSRegisteredEvents { registerEvent("protocols.implementations.VSReliableMulticastProtocol"); registerEvent("protocols.implementations.VSTwoPhaseCommitProtocol"); registerEvent("protocols.implementations.VSTimestampDemoProtocol"); - registerEvent("protocols.implementations.VSRaftProtocol"); /* Make dummy objects of each protocol, to see if they contain VSPrefs values to edit */ diff --git a/src/main/java/examples/CreateAndVerifyRaftSimulation.java b/src/main/java/examples/CreateAndVerifyRaftSimulation.java deleted file mode 100644 index 126c37c..0000000 --- a/src/main/java/examples/CreateAndVerifyRaftSimulation.java +++ /dev/null @@ -1,142 +0,0 @@ -package examples; - -import simulator.*; -import core.*; -import prefs.*; -import events.*; -import events.internal.*; -import events.implementations.*; -import serialize.VSSerialize; -import java.io.*; - -/** - * Creates a Raft simulation and verifies it can be loaded properly. - */ -public class CreateAndVerifyRaftSimulation { - - private static final String RAFT_PROTOCOL = "protocols.implementations.VSRaftProtocol"; - - public static void main(String[] args) throws Exception { - System.out.println("=== Creating and Verifying Raft Simulation ===\n"); - - // Initialize - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - // Step 1: Create the simulation - System.out.println("Step 1: Creating Raft simulation..."); - - VSSimulatorFrame frame = new VSSimulatorFrame(prefs, null); - VSSimulator simulator = new VSSimulator(prefs, frame); - frame.addSimulator(simulator); - - // Access visualization - java.lang.reflect.Field vizField = VSSimulator.class.getDeclaredField("simulatorVisualization"); - vizField.setAccessible(true); - VSSimulatorVisualization viz = (VSSimulatorVisualization) vizField.get(simulator); - - // Add processes (5 total: 3 servers + 2 clients) - while (viz.getNumProcesses() < 5) { - java.lang.reflect.Method addProcessMethod = VSSimulatorVisualization.class.getDeclaredMethod("addProcess"); - addProcessMethod.setAccessible(true); - addProcessMethod.invoke(viz); - } - - VSTaskManager taskManager = viz.getTaskManager(); - - // Add Raft server activations - System.out.println(" - Adding 3 Raft servers"); - for (int i = 0; i < 3; i++) { - VSProtocolEvent serverEvent = new VSProtocolEvent(); - serverEvent.setProtocolClassname(RAFT_PROTOCOL); - serverEvent.isClientProtocol(false); - serverEvent.isProtocolActivation(true); - - VSTask task = new VSTask(0, viz.getProcess(i), serverEvent, false); - taskManager.addTask(task); - } - - // Add Raft client activations - System.out.println(" - Adding 2 Raft clients"); - for (int i = 3; i < 5; i++) { - VSProtocolEvent clientEvent = new VSProtocolEvent(); - clientEvent.setProtocolClassname(RAFT_PROTOCOL); - clientEvent.isClientProtocol(true); - clientEvent.isProtocolActivation(true); - - // Stagger client starts - VSTask task = new VSTask(200 + (i-3)*100, viz.getProcess(i), clientEvent, false); - taskManager.addTask(task); - } - - // Add some events - System.out.println(" - Adding crash/recovery events"); - - // Server 0 crashes at 1000, recovers at 1500 - VSProcessCrashEvent crash = new VSProcessCrashEvent(); - taskManager.addTask(new VSTask(1000, viz.getProcess(0), crash, false)); - - VSProcessRecoverEvent recover = new VSProcessRecoverEvent(); - taskManager.addTask(new VSTask(1500, viz.getProcess(0), recover, false)); - - // Save simulation - File outputFile = new File("saved-simulations/raft-verified.dat"); - outputFile.getParentFile().mkdirs(); - - VSSerialize serialize = new VSSerialize(); - serialize.saveSimulator(outputFile.getAbsolutePath(), simulator); - - frame.dispose(); - - System.out.println(" āœ“ Simulation saved to: " + outputFile.getName()); - - // Step 2: Verify the simulation can be loaded - System.out.println("\nStep 2: Loading and verifying simulation..."); - - VSSimulatorFrame frame2 = new VSSimulatorFrame(prefs, null); - VSSimulator loadedSim = serialize.openSimulator(outputFile.getAbsolutePath(), frame2); - - if (loadedSim == null) { - System.err.println(" āœ— Failed to load simulation!"); - System.exit(1); - } - - // Verify contents - vizField = VSSimulator.class.getDeclaredField("simulatorVisualization"); - vizField.setAccessible(true); - VSSimulatorVisualization loadedViz = (VSSimulatorVisualization) vizField.get(loadedSim); - - System.out.println(" āœ“ Simulation loaded successfully"); - System.out.println(" - Processes: " + loadedViz.getNumProcesses()); - - // Check tasks - VSTaskManager loadedTaskManager = loadedViz.getTaskManager(); - java.lang.reflect.Field tasksField = VSTaskManager.class.getDeclaredField("tasks"); - tasksField.setAccessible(true); - Object taskQueue = tasksField.get(loadedTaskManager); - java.lang.reflect.Method sizeMethod = taskQueue.getClass().getMethod("size"); - int taskCount = (Integer) sizeMethod.invoke(taskQueue); - - System.out.println(" - Scheduled tasks: " + taskCount); - - frame2.dispose(); - - // Step 3: Provide instructions - System.out.println("\n=== Success! ==="); - System.out.println("\nTo run the Raft simulation:"); - System.out.println("1. Start the simulator:"); - System.out.println(" java -jar target/ds-sim-1.0.1-SNAPSHOT.jar"); - System.out.println("\n2. Load the simulation:"); - System.out.println(" File ā†’ Open ā†’ saved-simulations/raft-verified.dat"); - System.out.println("\n3. Run the simulation:"); - System.out.println(" Click the 'Run' button (ā–¶)"); - System.out.println("\n4. What to look for:"); - System.out.println(" - Leader election messages (REQUEST_VOTE, VOTE_RESPONSE)"); - System.out.println(" - Heartbeats from leader (APPEND_ENTRIES)"); - System.out.println(" - Client requests and responses"); - System.out.println(" - Re-election when server 0 crashes at time 1000"); - - System.exit(0); - } -} \ No newline at end of file diff --git a/src/main/java/examples/CreateMinimalRaftSimulation.java b/src/main/java/examples/CreateMinimalRaftSimulation.java deleted file mode 100644 index 62db468..0000000 --- a/src/main/java/examples/CreateMinimalRaftSimulation.java +++ /dev/null @@ -1,86 +0,0 @@ -package examples; - -import simulator.*; -import core.*; -import prefs.*; -import events.*; -import events.internal.*; -import serialize.VSSerialize; -import java.io.*; -import java.lang.reflect.*; - -/** - * Creates a minimal Raft simulation with just protocol activations. - * This tests if the basic simulation saving/loading works. - */ -public class CreateMinimalRaftSimulation { - - public static void main(String[] args) throws Exception { - System.out.println("=== Creating Minimal Raft Simulation ===\n"); - - // Initialize - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - // Create simulator without GUI - VSSimulatorFrame frame = new VSSimulatorFrame(prefs, null); - VSSimulator simulator = new VSSimulator(prefs, frame); - frame.addSimulator(simulator); - - // Access visualization via reflection - Field vizField = VSSimulator.class.getDeclaredField("simulatorVisualization"); - vizField.setAccessible(true); - VSSimulatorVisualization viz = (VSSimulatorVisualization) vizField.get(simulator); - - // Add 3 processes - Method addProcessMethod = VSSimulatorVisualization.class.getDeclaredMethod("addProcess"); - addProcessMethod.setAccessible(true); - for (int i = 0; i < 3; i++) { - addProcessMethod.invoke(viz); - } - - VSTaskManager taskManager = viz.getTaskManager(); - - // Create only one Raft server activation at time 0 - System.out.println("Adding single Raft server activation on process 0..."); - VSProtocolEvent serverEvent = new VSProtocolEvent(); - serverEvent.setProtocolClassname("protocols.implementations.VSRaftProtocol"); - serverEvent.isClientProtocol(false); - serverEvent.isProtocolActivation(true); - - VSTask task = new VSTask(0, viz.getProcess(0), serverEvent, false); - taskManager.addTask(task); - - // Save simulation - File outputFile = new File("saved-simulations/raft-minimal.dat"); - outputFile.getParentFile().mkdirs(); - - VSSerialize serialize = new VSSerialize(); - serialize.saveSimulator(outputFile.getAbsolutePath(), simulator); - - frame.dispose(); - - System.out.println("\nSimulation saved to: " + outputFile.getAbsolutePath()); - System.out.println("\nTo test:"); - System.out.println("1. Run: java -jar target/ds-sim-1.0.1-SNAPSHOT.jar"); - System.out.println("2. File ā†’ Open ā†’ saved-simulations/raft-minimal.dat"); - System.out.println("3. Click Run button and check the logs"); - - // Try to immediately load it back to verify - System.out.println("\nVerifying saved file can be loaded..."); - try { - VSSimulatorFrame frame2 = new VSSimulatorFrame(prefs, null); - VSSimulator loaded = serialize.openSimulator(outputFile.getAbsolutePath(), frame2); - if (loaded != null) { - System.out.println("āœ“ File loaded successfully!"); - frame2.dispose(); - } else { - System.out.println("āœ— Failed to load file!"); - } - } catch (Exception e) { - System.out.println("āœ— Error loading file: " + e.getMessage()); - e.printStackTrace(); - } - } -} \ No newline at end of file diff --git a/src/main/java/examples/CreateSimpleRaftSimulation.java b/src/main/java/examples/CreateSimpleRaftSimulation.java deleted file mode 100644 index ebff53e..0000000 --- a/src/main/java/examples/CreateSimpleRaftSimulation.java +++ /dev/null @@ -1,123 +0,0 @@ -package examples; - -import simulator.*; -import core.*; -import prefs.*; -import events.*; -import events.internal.*; -import events.implementations.*; -import serialize.VSSerialize; -import java.io.*; - -/** - * Creates a simple working Raft simulation. - * The key insight: Raft protocol uses HAS_ON_SERVER_START, so when servers - * are activated via VSProtocolEvent, the protocol's onServerStart() method - * will be called automatically. - */ -public class CreateSimpleRaftSimulation { - - private static final String RAFT_PROTOCOL = "protocols.implementations.VSRaftProtocol"; - - public static void main(String[] args) throws Exception { - // Initialize - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - // Create frame and simulator - VSSimulatorFrame frame = new VSSimulatorFrame(prefs, null); - VSSimulator simulator = new VSSimulator(prefs, frame); - frame.addSimulator(simulator); - - // Access visualization via reflection - java.lang.reflect.Field vizField = VSSimulator.class.getDeclaredField("simulatorVisualization"); - vizField.setAccessible(true); - VSSimulatorVisualization viz = (VSSimulatorVisualization) vizField.get(simulator); - - // Add more processes - we want 5 total (3 servers, 2 clients) - while (viz.getNumProcesses() < 5) { - java.lang.reflect.Method addProcessMethod = VSSimulatorVisualization.class.getDeclaredMethod("addProcess"); - addProcessMethod.setAccessible(true); - addProcessMethod.invoke(viz); - } - - VSTaskManager taskManager = viz.getTaskManager(); - - // Activate Raft SERVERS on processes 0, 1, 2 - // Since Raft uses HAS_ON_SERVER_START, onServerStart() will be called automatically! - System.out.println("Creating Raft server activations..."); - for (int i = 0; i < 3; i++) { - VSProtocolEvent serverEvent = new VSProtocolEvent(); - serverEvent.setProtocolClassname(RAFT_PROTOCOL); - serverEvent.isClientProtocol(false); // Server mode - serverEvent.isProtocolActivation(true); // Activation - - // Activate at time 0 - VSTask task = new VSTask(0, viz.getProcess(i), serverEvent, false); - taskManager.addTask(task); - System.out.println(" - Server " + i + " will activate at time 0"); - } - - // Activate Raft CLIENTS on processes 3, 4 - // Clients will react to server heartbeats and start sending requests - System.out.println("\nCreating Raft client activations..."); - for (int i = 3; i < 5; i++) { - VSProtocolEvent clientEvent = new VSProtocolEvent(); - clientEvent.setProtocolClassname(RAFT_PROTOCOL); - clientEvent.isClientProtocol(true); // Client mode - clientEvent.isProtocolActivation(true); // Activation - - // Activate clients a bit later so servers have time to elect leader - VSTask task = new VSTask(300 + (i-3)*100, viz.getProcess(i), clientEvent, false); - taskManager.addTask(task); - System.out.println(" - Client " + (i-3) + " will activate at time " + (300 + (i-3)*100)); - } - - // Add crash/recovery to demonstrate leader re-election - System.out.println("\nAdding failure scenarios..."); - - // Crash server 0 at time 1000 - VSProcessCrashEvent crash = new VSProcessCrashEvent(); - VSTask crashTask = new VSTask(1000, viz.getProcess(0), crash, false); - taskManager.addTask(crashTask); - System.out.println(" - Server 0 will crash at time 1000"); - - // Recover server 0 at time 1500 - VSProcessRecoverEvent recover = new VSProcessRecoverEvent(); - VSTask recoverTask = new VSTask(1500, viz.getProcess(0), recover, false); - taskManager.addTask(recoverTask); - System.out.println(" - Server 0 will recover at time 1500"); - - // Save simulation - File outputFile = new File("saved-simulations/raft-simple.dat"); - outputFile.getParentFile().mkdirs(); - - VSSerialize serialize = new VSSerialize(); - serialize.saveSimulator(outputFile.getAbsolutePath(), simulator); - - frame.dispose(); - - System.out.println("\n==========================================="); - System.out.println("Simple Raft simulation saved successfully!"); - System.out.println("==========================================="); - System.out.println("\nFile: " + outputFile.getAbsolutePath()); - System.out.println("\nWhat happens in this simulation:"); - System.out.println("1. Time 0: Three Raft servers start and begin leader election"); - System.out.println("2. Time ~150-300: One server becomes leader (watch for election messages)"); - System.out.println("3. Time 300: First client activates and starts sending requests"); - System.out.println("4. Time 400: Second client activates and starts sending requests"); - System.out.println("5. Time 1000: Server 0 crashes, triggering new leader election"); - System.out.println("6. Time 1500: Server 0 recovers and rejoins as follower"); - System.out.println("\nTo run the simulation:"); - System.out.println("1. java -jar target/ds-sim-1.0.1-SNAPSHOT.jar"); - System.out.println("2. File -> Open -> saved-simulations/raft-simple.dat"); - System.out.println("3. Click 'Run' and watch the Raft consensus in action!"); - System.out.println("\nLook for:"); - System.out.println("- REQUEST_VOTE and VOTE_RESPONSE messages during elections"); - System.out.println("- APPEND_ENTRIES messages (heartbeats) from leader"); - System.out.println("- CLIENT_REQUEST messages and their processing"); - - System.exit(0); - } -} \ No newline at end of file diff --git a/src/main/java/examples/CreateWorkingRaftSimulation.java b/src/main/java/examples/CreateWorkingRaftSimulation.java deleted file mode 100644 index 0bc5df4..0000000 --- a/src/main/java/examples/CreateWorkingRaftSimulation.java +++ /dev/null @@ -1,152 +0,0 @@ -package examples; - -import simulator.*; -import core.*; -import prefs.*; -import events.*; -import events.internal.*; -import events.implementations.*; -import serialize.VSSerialize; -import java.io.*; -import java.lang.reflect.*; - -/** - * Creates a working Raft simulation by properly setting up the event queue - * and ensuring protocols are activated through the normal event system. - */ -public class CreateWorkingRaftSimulation { - - private static final String RAFT_PROTOCOL = "protocols.implementations.VSRaftProtocol"; - - public static void main(String[] args) throws Exception { - System.out.println("=== Creating Working Raft Simulation ===\n"); - - // Initialize - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - // Create simulator with frame - VSSimulatorFrame frame = new VSSimulatorFrame(prefs, null); - VSSimulator simulator = new VSSimulator(prefs, frame); - frame.addSimulator(simulator); - - // Access visualization - Field vizField = VSSimulator.class.getDeclaredField("simulatorVisualization"); - vizField.setAccessible(true); - VSSimulatorVisualization viz = (VSSimulatorVisualization) vizField.get(simulator); - - // Add 5 processes (3 servers + 2 clients) - Method addProcessMethod = VSSimulatorVisualization.class.getDeclaredMethod("addProcess"); - addProcessMethod.setAccessible(true); - System.out.println("Adding 5 processes..."); - for (int i = 0; i < 5; i++) { - addProcessMethod.invoke(viz); - } - - VSTaskManager taskManager = viz.getTaskManager(); - - // Schedule Raft server activations at time 0 - System.out.println("\nScheduling Raft server activations:"); - for (int i = 0; i < 3; i++) { - VSProtocolEvent serverEvent = new VSProtocolEvent(); - serverEvent.setProtocolClassname(RAFT_PROTOCOL); - serverEvent.isClientProtocol(false); // Server mode - serverEvent.isProtocolActivation(true); // This is an activation - - VSTask task = new VSTask(0, viz.getProcess(i), serverEvent, false); - taskManager.addTask(task); - System.out.println(" - Server " + i + " activation scheduled at time 0"); - } - - // Schedule Raft client activations with slight delay - System.out.println("\nScheduling Raft client activations:"); - for (int i = 3; i < 5; i++) { - VSProtocolEvent clientEvent = new VSProtocolEvent(); - clientEvent.setProtocolClassname(RAFT_PROTOCOL); - clientEvent.isClientProtocol(true); // Client mode - clientEvent.isProtocolActivation(true); // This is an activation - - // Start clients after servers have initialized - long startTime = 500 + (i - 3) * 200; - VSTask task = new VSTask(startTime, viz.getProcess(i), clientEvent, false); - taskManager.addTask(task); - System.out.println(" - Client " + (i-3) + " activation scheduled at time " + startTime); - } - - // Add some interesting events - System.out.println("\nAdding crash/recovery events:"); - - // Process 0 crashes at time 2000 and recovers at 3000 - VSProcessCrashEvent crash1 = new VSProcessCrashEvent(); - taskManager.addTask(new VSTask(2000, viz.getProcess(0), crash1, false)); - System.out.println(" - Server 0 crash scheduled at time 2000"); - - VSProcessRecoverEvent recover1 = new VSProcessRecoverEvent(); - taskManager.addTask(new VSTask(3000, viz.getProcess(0), recover1, false)); - System.out.println(" - Server 0 recovery scheduled at time 3000"); - - // Process 1 crashes at time 4000 and recovers at 5000 - VSProcessCrashEvent crash2 = new VSProcessCrashEvent(); - taskManager.addTask(new VSTask(4000, viz.getProcess(1), crash2, false)); - System.out.println(" - Server 1 crash scheduled at time 4000"); - - VSProcessRecoverEvent recover2 = new VSProcessRecoverEvent(); - taskManager.addTask(new VSTask(5000, viz.getProcess(1), recover2, false)); - System.out.println(" - Server 1 recovery scheduled at time 5000"); - - // Save simulation - File outputFile = new File("saved-simulations/raft-working.dat"); - outputFile.getParentFile().mkdirs(); - - System.out.println("\nSaving simulation..."); - VSSerialize serialize = new VSSerialize(); - serialize.saveSimulator(outputFile.getAbsolutePath(), simulator); - - frame.dispose(); - - System.out.println("\nāœ“ Simulation saved to: " + outputFile.getAbsolutePath()); - - // Create instruction file - File instructionFile = new File("saved-simulations/README-raft.txt"); - try (PrintWriter writer = new PrintWriter(instructionFile)) { - writer.println("RAFT CONSENSUS SIMULATION"); - writer.println("========================"); - writer.println(); - writer.println("This directory contains Raft consensus protocol simulations:"); - writer.println(); - writer.println("1. raft-working.dat - Full working simulation with:"); - writer.println(" - 3 Raft servers (processes 0-2)"); - writer.println(" - 2 Raft clients (processes 3-4)"); - writer.println(" - Server crash/recovery events"); - writer.println(); - writer.println("To run the simulation:"); - writer.println("1. java -jar target/ds-sim-1.0.1-SNAPSHOT.jar"); - writer.println("2. File ā†’ Open ā†’ saved-simulations/raft-working.dat"); - writer.println("3. Click Run (ā–¶) button"); - writer.println(); - writer.println("What to look for:"); - writer.println("- Leader election (REQUEST_VOTE messages)"); - writer.println("- Heartbeats from leader (APPEND_ENTRIES)"); - writer.println("- Client requests and responses"); - writer.println("- Re-election when servers crash"); - writer.println(); - writer.println("Timeline:"); - writer.println("- Time 0: Servers start, begin leader election"); - writer.println("- Time 500-700: Clients start"); - writer.println("- Time 2000: Server 0 crashes"); - writer.println("- Time 3000: Server 0 recovers"); - writer.println("- Time 4000: Server 1 crashes"); - writer.println("- Time 5000: Server 1 recovers"); - } - - System.out.println("āœ“ Instructions saved to: " + instructionFile.getAbsolutePath()); - - System.out.println("\n=== Success! ==="); - System.out.println("\nThe Raft simulation has been created with the following setup:"); - System.out.println("- 3 servers implementing Raft consensus"); - System.out.println("- 2 clients that will send requests"); - System.out.println("- Crash/recovery events to test fault tolerance"); - System.out.println("\nRun the simulator and load the file to see it in action!"); - } -} \ No newline at end of file diff --git a/src/main/java/examples/RaftSimulationBuilder.java b/src/main/java/examples/RaftSimulationBuilder.java deleted file mode 100644 index c802448..0000000 --- a/src/main/java/examples/RaftSimulationBuilder.java +++ /dev/null @@ -1,76 +0,0 @@ -package examples; - -import simulator.*; -import core.*; -import prefs.*; -import events.*; -import events.internal.*; -import serialize.VSSerialize; -import java.io.*; - -/** - * Builder for creating Raft simulations programmatically. - * Uses reflection to access private simulator fields when necessary. - */ -public class RaftSimulationBuilder { - - private static final String RAFT_PROTOCOL = "protocols.implementations.VSRaftProtocol"; - - public static void main(String[] args) throws Exception { - // Initialize - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - // Create frame and simulator - VSSimulatorFrame frame = new VSSimulatorFrame(prefs, null); - VSSimulator simulator = new VSSimulator(prefs, frame); - frame.addSimulator(simulator); - - // Access private field via reflection - java.lang.reflect.Field vizField = VSSimulator.class.getDeclaredField("simulatorVisualization"); - vizField.setAccessible(true); - VSSimulatorVisualization viz = (VSSimulatorVisualization) vizField.get(simulator); - - // Build Raft simulation - VSTaskManager taskManager = viz.getTaskManager(); - - // Add server activations (processes 0,1) - for (int i = 0; i < 2; i++) { - VSProtocolEvent serverEvent = new VSProtocolEvent(); - serverEvent.setProtocolClassname(RAFT_PROTOCOL); - serverEvent.isClientProtocol(false); - serverEvent.isProtocolActivation(true); - - VSTask task = new VSTask(0, viz.getProcess(i), serverEvent, false); - taskManager.addTask(task); - } - - // Add client activation (process 2) - VSProtocolEvent clientEvent = new VSProtocolEvent(); - clientEvent.setProtocolClassname(RAFT_PROTOCOL); - clientEvent.isClientProtocol(true); - clientEvent.isProtocolActivation(true); - - VSTask clientTask = new VSTask(100, viz.getProcess(2), clientEvent, false); - taskManager.addTask(clientTask); - - // Save - File outputFile = new File("saved-simulations/raft-consensus.dat"); - outputFile.getParentFile().mkdirs(); - - VSSerialize serialize = new VSSerialize(); - serialize.saveSimulator(outputFile.getAbsolutePath(), simulator); - - frame.dispose(); - - System.out.println("Raft simulation created: " + outputFile.getAbsolutePath()); - System.out.println("\nContains:"); - System.out.println("- 2 Raft servers (processes 0-1)"); - System.out.println("- 1 Raft client (process 2)"); - System.out.println("\nRun with: java -jar target/ds-sim-1.0.1-SNAPSHOT.jar"); - System.out.println("Then open: " + outputFile.getName()); - - System.exit(0); - } -} \ No newline at end of file diff --git a/src/main/java/examples/TestRaftLoading.java b/src/main/java/examples/TestRaftLoading.java deleted file mode 100644 index ebad379..0000000 --- a/src/main/java/examples/TestRaftLoading.java +++ /dev/null @@ -1,57 +0,0 @@ -package examples; - -import events.VSRegisteredEvents; -import prefs.VSDefaultPrefs; -import java.util.Vector; - -/** - * Test if Raft protocol is properly registered and loadable - */ -public class TestRaftLoading { - public static void main(String[] args) { - // Initialize - VSDefaultPrefs prefs = new VSDefaultPrefs(); - prefs.fillWithDefaults(); - VSRegisteredEvents.init(prefs); - - // List all registered protocols - System.out.println("=== Registered Protocols ==="); - Vector protocolNames = VSRegisteredEvents.getProtocolNames(); - for (String name : protocolNames) { - String className = VSRegisteredEvents.getClassnameByEventname(name); - System.out.println(name + " -> " + className); - } - - System.out.println("\n=== Protocol Classnames ==="); - Vector protocolClassnames = VSRegisteredEvents.getProtocolClassnames(); - for (String className : protocolClassnames) { - String shortName = VSRegisteredEvents.getShortnameByClassname(className); - System.out.println(className + " (short: " + shortName + ")"); - } - - // Check Raft specifically - System.out.println("\n=== Raft Protocol Check ==="); - String raftClass = "protocols.implementations.VSRaftProtocol"; - String raftShortName = VSRegisteredEvents.getShortnameByClassname(raftClass); - String raftEventName = VSRegisteredEvents.getNameByClassname(raftClass); - - System.out.println("Class: " + raftClass); - System.out.println("Short name: " + raftShortName); - System.out.println("Event name: " + raftEventName); - - // Try to load the class - try { - Class clazz = Class.forName(raftClass); - System.out.println("Class loaded successfully: " + clazz.getName()); - - // Check if it's a protocol - if (protocols.VSAbstractProtocol.class.isAssignableFrom(clazz)) { - System.out.println("āœ“ Is a valid protocol class"); - } else { - System.out.println("āœ— NOT a protocol class!"); - } - } catch (ClassNotFoundException e) { - System.out.println("āœ— Class not found: " + e.getMessage()); - } - } -} \ No newline at end of file diff --git a/src/main/java/protocols/implementations/VSRaftProtocol.java b/src/main/java/protocols/implementations/VSRaftProtocol.java deleted file mode 100644 index af12064..0000000 --- a/src/main/java/protocols/implementations/VSRaftProtocol.java +++ /dev/null @@ -1,603 +0,0 @@ -package protocols.implementations; - -import java.util.*; -import java.util.concurrent.ConcurrentHashMap; - -import core.VSMessage; -import core.VSInternalProcess; -import protocols.VSAbstractProtocol; - -/** - * Implementation of the Raft consensus algorithm. - * - * Raft is a consensus algorithm designed to be understandable. It ensures that - * a distributed system agrees on values even in the presence of failures. - * - *

The protocol has three states:

- *
    - *
  • Follower - Passive state, responds to leaders
    • - *
  • Candidate - Actively requesting votes to become leader
    • - *
  • Leader - Manages the cluster and log replication
    • - *
- * - *

Key features implemented:

- *
    - *
  • Leader election with randomized timeouts
    • - *
  • Log replication for state machine commands
    • - *
  • Safety through term numbers and log matching
    • - *
  • Membership changes (simplified)
    • - *
- * - * @author Paul C. Buetow - */ -public class VSRaftProtocol extends VSAbstractProtocol { - - // Raft states - private enum State { - FOLLOWER, - CANDIDATE, - LEADER - } - - // Message types - private static final String MSG_REQUEST_VOTE = "REQUEST_VOTE"; - private static final String MSG_VOTE_RESPONSE = "VOTE_RESPONSE"; - private static final String MSG_APPEND_ENTRIES = "APPEND_ENTRIES"; - private static final String MSG_APPEND_RESPONSE = "APPEND_RESPONSE"; - private static final String MSG_CLIENT_REQUEST = "CLIENT_REQUEST"; - - // Timing constants (in simulation time units) - private static final long HEARTBEAT_INTERVAL = 50; - private static final long ELECTION_TIMEOUT_MIN = 150; - private static final long ELECTION_TIMEOUT_MAX = 300; - - // Server state (persistent - should be saved to stable storage) - private State currentState; - private int currentTerm; - private Integer votedFor; - private List log; - - // Server state (volatile) - private int commitIndex; - private int lastApplied; - - // Leader state (reinitialized after election) - private Map nextIndex; - private Map matchIndex; - - // Candidate state - private Set votesReceived; - private long electionTimeout; - - // General state - private Integer currentLeader; - private long lastHeartbeat; - - // Client state - private boolean clientHasScheduled = false; - private int clientRequestCount = 0; - - /** - * Log entry structure - */ - private static class LogEntry { - final int term; - final String command; - final long timestamp; - - LogEntry(int term, String command, long timestamp) { - this.term = term; - this.command = command; - this.timestamp = timestamp; - } - - @Override - public String toString() { - return String.format("LogEntry{term=%d, cmd='%s', time=%d}", - term, command, timestamp); - } - } - - public VSRaftProtocol() { - super(VSAbstractProtocol.HAS_ON_SERVER_START); - setClassname(getClass().toString()); - } - - @Override - public void onServerInit() { - currentState = State.FOLLOWER; - currentTerm = 0; - votedFor = null; - log = new ArrayList<>(); - commitIndex = 0; - lastApplied = 0; - nextIndex = new ConcurrentHashMap<>(); - matchIndex = new ConcurrentHashMap<>(); - votesReceived = new HashSet<>(); - currentLeader = null; - - // Add a dummy entry at index 0 for easier indexing - log.add(new LogEntry(0, "INIT", 0)); - } - - @Override - public void onServerStart() { - // Initialize election timeout and start - resetElectionTimeout(); - raftLog("Raft node initialized as FOLLOWER, election timeout=" + electionTimeout); - scheduleElectionTimeout(); - raftLog("Scheduled election timeout check"); - } - - @Override - public void onServerReset() { - onServerInit(); - removeSchedules(); - } - - @Override - public void onServerRecv(VSMessage message) { - String msgType = message.getString("type"); - int term = message.getInteger("term"); - int senderId = message.getSendingProcess().getProcessNum(); - - // Check if this message is intended for us (for unicast messages) - if (message.objectExists("receiverNum")) { - int receiverNum = message.getInteger("receiverNum"); - if (receiverNum != process.getProcessNum()) { - // Message not for us, ignore it - return; - } - } - - // If we receive a message with a higher term, become follower - if (term > currentTerm) { - curr