Full remodeling to FalkorDB

rebase code base to use falkordb java client and full implementation of Object mapping of Graph entities

Author: shahar-biron

.github/PULL_REQUEST_TEMPLATE.md

@@ -5,7 +5,7 @@ Make sure that:
 
 -->
 
-- [ ] You have read the [Spring Data Neo4j contribution guidelines](https://github.com/spring-projects/spring-data-neo4j/blob/master/CONTRIBUTING.adoc).
+- [ ] You have read the [Spring Data FalkorDB contribution guidelines](https://github.com/falkordb/spring-data-falkordb/blob/master/CONTRIBUTING.adoc).
 - [ ] You use the code formatters provided [here](https://github.com/spring-projects/spring-data-build/tree/master/etc/ide) and have them applied to your changes. Don’t submit any formatting related changes.
 - [ ] You submit test cases (unit or integration tests) that back your changes.
 - [ ] You added yourself as author in the headers of the classes you touched. Amend the date range in the Apache license header if needed. For new types, add the license header (copy from another file and set the current year only).

CI.adoc

@@ -0,0 +1,227 @@
+# 🚀 FalkorDB Spring Data Integration Test
+
+This directory contains a comprehensive integration test that demonstrates the FalkorDB Spring Data library working with a real FalkorDB instance using a Twitter-like social graph.
+
+## 📋 Prerequisites
+
+1. **FalkorDB Server**: You need FalkorDB running locally on port 6379
+2. **Java 17+**: Make sure Java 17 or later is installed
+3. **Maven**: Required for building and running the test
+
+## 🏗️ Starting FalkorDB
+
+### Option 1: Using Docker (Recommended)
+```bash
+docker run -p 6379:6379 falkordb/falkordb:latest
+```
+
+### Option 2: Using Native Installation
+If you have FalkorDB installed natively:
+```bash
+falkordb-server --port 6379
+```
+
+### Option 3: Using Redis with FalkorDB Module
+If you have Redis with FalkorDB module:
+```bash
+redis-server --port 6379 --loadmodule /path/to/falkordb.so
+```
+
+## 🧪 Running the Test
+
+### Quick Run (Automated Script)
+```bash
+./run-falkordb-test.sh
+```
+
+### Manual Run
+1. **Compile the project:**
+   ```bash
+   mvn compile -Dcheckstyle.skip=true -Dmaven.javadoc.skip=true
+   ```
+
+2. **Run the integration test:**
+   ```bash
+   mvn exec:java -Dexec.mainClass="org.springframework.data.falkordb.integration.FalkorDBTwitterIntegrationTest" -Dexec.classpathScope="test"
+   ```
+
+### JUnit Test Runner
+You can also run individual tests using JUnit:
+```bash
+mvn test -Dtest=FalkorDBTwitterIntegrationTest
+```
+
+## 🌐 What the Test Does
+
+The integration test creates a comprehensive Twitter-like social graph and demonstrates:
+
+### 🎭 Entity Creation
+- **TwitterUser**: Users with profiles, follower counts, verification status
+- **Tweet**: Tweets with text, timestamps, engagement metrics
+- **Hashtag**: Hashtags with usage tracking
+
+### 🔗 Relationship Types
+- `FOLLOWS`: User following relationships
+- `POSTED`: Users posting tweets
+- `LIKED`: Users liking tweets
+- `RETWEETED`: Users retweeting tweets
+- `MENTIONS`: Tweets mentioning users
+- `HAS_HASHTAG`: Tweets containing hashtags
+- `REPLIES_TO`: Tweet reply chains
+
+### 📊 Test Scenarios
+
+1. **Connection & Basic Operations**
+   - Connect to FalkorDB instance
+   - Create and save entities
+   - Retrieve entities by ID
+
+2. **Twitter Network Creation**
+   - Create influential users (Elon Musk, Bill Gates, Oprah)
+   - Set up realistic profiles with follower counts
+   - Create tweets and relationships
+
+3. **Relationship Traversal**
+   - Follow relationships between users
+   - Find mutual connections
+   - Navigate relationship paths
+
+4. **Complex Queries**
+   - Analytics queries (user counts, tweet counts)
+   - Find most followed users
+   - Search verified users
+   - Filter by follower thresholds
+
+## 📈 Sample Output
+
+```
+🚀 Starting FalkorDB Twitter Integration Test
+================================================================================
+=== Testing FalkorDB Connection and Basic Operations ===
+✅ Saved user: TwitterUser{id=1, username='testuser', displayName='Test User', ...}
+✅ Retrieved user: TwitterUser{id=1, username='testuser', displayName='Test User', ...}
+
+================================================================================
+=== Testing Twitter Graph Creation and Traversal ===
+Created Twitter network with users:
+- TwitterUser{id=2, username='elonmusk', displayName='Elon Musk', followerCount=150000000, verified=true}
+- TwitterUser{id=3, username='billgates', displayName='Bill Gates', followerCount=60000000, verified=true}
+- TwitterUser{id=4, username='oprah', displayName='Oprah Winfrey', followerCount=45000000, verified=true}
+
+Found 3 verified users:
+  - Elon Musk (@elonmusk) - 150000000 followers
+  - Bill Gates (@billgates) - 60000000 followers
+  - Oprah Winfrey (@oprah) - 45000000 followers
+
+================================================================================
+=== Testing Relationship Traversal ===
+Alice follows 2 users:
+  - Bob Smith
+  - Charlie Brown
+Bob has 1 followers:
+  - Alice Johnson
+Alice and Charlie both follow 1 users:
+  - Bob Smith
+
+================================================================================
+🎉 All tests completed successfully!
+FalkorDB Spring Data integration is working correctly.
+```
+
+## 🔍 Inspecting the Graph
+
+After running the test, you can inspect the created graph using the Redis CLI:
+
+```bash
+redis-cli -p 6379
+```
+
+### Useful Queries
+
+```cypher
+# View all nodes
+GRAPH.QUERY TWITTER 'MATCH (n) RETURN n LIMIT 10'
+
+# View all users
+GRAPH.QUERY TWITTER 'MATCH (u:User) RETURN u.username, u.display_name, u.follower_count'
+
+# View follow relationships
+GRAPH.QUERY TWITTER 'MATCH (u1:User)-[:FOLLOWS]->(u2:User) RETURN u1.username, u2.username'
+
+# View tweets with authors
+GRAPH.QUERY TWITTER 'MATCH (u:User)-[:POSTED]->(t:Tweet) RETURN u.username, t.text'
+
+# Find verified users
+GRAPH.QUERY TWITTER 'MATCH (u:User) WHERE u.verified = true RETURN u.username, u.follower_count ORDER BY u.follower_count DESC'
+
+# Count nodes by type
+GRAPH.QUERY TWITTER 'MATCH (u:User) RETURN "Users" as type, count(u) as count UNION MATCH (t:Tweet) RETURN "Tweets" as type, count(t) as count'
+
+# Clear the graph (if needed)
+GRAPH.QUERY TWITTER 'MATCH (n) DETACH DELETE n'
+```
+
+## 🏗️ Architecture Demonstrated
+
+### Spring Data FalkorDB Components Used
+
+1. **FalkorDBClient**: Direct connection to FalkorDB server
+2. **FalkorDBTemplate**: High-level operations template
+3. **Entity Mapping**: JPA-style annotations for graph entities
+4. **Relationship Mapping**: Automatic relationship traversal
+5. **Repository Pattern**: Spring Data repository interfaces
+6. **Query Methods**: Derived and custom query methods
+
+### Annotations Used
+
+- `@Node`: Mark classes as graph nodes
+- `@Id`: Specify entity identifiers
+- `@GeneratedValue`: Auto-generate IDs
+- `@Property`: Map properties to graph attributes
+- `@Relationship`: Define relationships between entities
+
+## 🎯 Key Features Demonstrated
+
+✅ **Connection Management**: Robust FalkorDB connectivity  
+✅ **Entity Persistence**: Save and retrieve complex objects  
+✅ **Relationship Handling**: Navigate graph relationships  
+✅ **Query Execution**: Custom Cypher query support  
+✅ **Collection Support**: Handle lists of related entities  
+✅ **Type Safety**: Strongly-typed entity conversion  
+✅ **Error Handling**: Graceful failure management  
+
+## 🚨 Troubleshooting
+
+### FalkorDB Not Running
+```
+❌ FalkorDB connection failed: Connection refused
+```
+**Solution**: Make sure FalkorDB is running on localhost:6379
+
+### Compilation Errors
+```
+❌ Compilation failed
+```
+**Solution**: Ensure Java 17+ is installed and JAVA_HOME is set correctly
+
+### Permission Denied
+```
+❌ Permission denied: ./run-falkordb-test.sh
+```
+**Solution**: Make the script executable: `chmod +x run-falkordb-test.sh`
+
+### Memory Issues
+If you encounter OutOfMemoryError, increase Java heap size:
+```bash
+export MAVEN_OPTS="-Xmx2g"
+```
+
+## 📚 Further Reading
+
+- [FalkorDB Documentation](https://www.falkordb.com/docs/)
+- [Spring Data Documentation](https://spring.io/projects/spring-data)
+- [Graph Database Concepts](https://www.falkordb.com/docs/graph-concepts)
+
+---
+
+🎉 **Happy Graph Traversing with FalkorDB and Spring Data!** 🎉