Apache Cassandra Implementation for Chat Service

docker-compose.yml

@@ -50,6 +50,29 @@ services:
     volumes:
       - ./data/minio:/data
 
+  cassandra-seed:
+    image: cassandra:latest
+    container_name: cassandra-seed
+    environment:
+      - CASSANDRA_CLUSTER_NAME=remsfal-cassandra-cluster
+      - CASSANDRA_NUM_TOKENS=8
+      - CASSANDRA_SEEDS=cassandra-seed
+      - CASSANDRA_USER=admin
+      - CASSANDRA_PASSWORD=admin
+    ports:
+      - "9042:9042"
+      - "7000:7000"
+
+  cassandra-node1:
+    image: cassandra:latest
+    container_name: cassandra-node1
+    environment:
+      - CASSANDRA_CLUSTER_NAME=remsfal-cassandra-cluster
+      - CASSANDRA_SEEDS=cassandra-seed
+    ports:
+      - "9043:9042" # Alternative port mapping for node1
+      - "7001:7000"
+
 
 networks:
   remsfal:

remsfal-core/src/main/java/de/remsfal/core/api/project/ChatEndpoint.java

@@ -1,7 +1,6 @@
 package de.remsfal.core.api.project;
 
 import de.remsfal.core.json.project.ChatMessageJson;
-import de.remsfal.core.model.project.ChatSessionModel;
 import de.remsfal.core.validation.UUID;
 import jakarta.validation.Valid;
 import jakarta.validation.constraints.NotNull;
@@ -48,7 +47,8 @@ public interface ChatEndpoint {
     @APIResponse(responseCode = "500", description = "Internal server error")
     @APIResponse(responseCode = "401", description = "No user authentication provided via session cookie")
     Response getChatSession(
-        @PathParam("sessionId") @NotNull @UUID String sessionId);
+        @PathParam("sessionId") @NotNull @UUID String sessionId
+    );
 
     @DELETE
     @Path("/{sessionId}")
@@ -75,7 +75,7 @@ Response deleteChatSession(
     Response updateChatSessionStatus(
         @PathParam("sessionId") @NotNull @UUID String sessionId,
         @Parameter(description = "New status for the chat session", required = true)
-        @Valid @NotNull ChatSessionModel.Status status);
+        @Valid @NotNull String status);
 
     @POST
     @Path("/{sessionId}")
@@ -131,7 +131,7 @@ Response changeParticipantRole(
         @Parameter(description = "The participant ID", required = true) @PathParam("participantId")
         @NotNull @UUID String participantId,
         @Parameter(description = "New role for the participant", required = true)
-        @Valid @NotNull ChatSessionModel.ParticipantRole role);
+        @Valid @NotNull String role);
 
     @DELETE
     @Path("/{sessionId}/participants/{participantId}")

remsfal-core/src/main/java/de/remsfal/core/json/project/ChatMessageJson.java

@@ -1,19 +1,15 @@
 package de.remsfal.core.json.project;
 
-import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.databind.PropertyNamingStrategies;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonNaming;
-import de.remsfal.core.model.UserModel;
 import de.remsfal.core.model.project.ChatMessageModel;
-import de.remsfal.core.model.project.ChatSessionModel;
-import de.remsfal.core.validation.UUID;
 import jakarta.annotation.Nullable;
 import jakarta.validation.constraints.Null;
 import org.eclipse.microprofile.openapi.annotations.media.Schema;
 import org.immutables.value.Value;
-
-import java.util.Date;
+import java.time.Instant;
+import java.util.UUID;
 
 /**
  * @author: Parham Rahmani [parham.rahmani@student.htw-berlin.de]
@@ -27,22 +23,19 @@ public abstract class ChatMessageJson implements ChatMessageModel {
     @Null
     @Nullable
     @Override
-    @UUID
-    public abstract String getId();
+    public abstract UUID getMessageId();
 
     @Nullable
     @Override
-    @UUID
-    public abstract String getChatSessionId();
+    public abstract UUID getChatSessionId();
 
     @Nullable
     @Override
-    @UUID
-    public abstract String getSenderId();
+    public abstract UUID getSenderId();
 
     @Nullable
     @Override
-    public abstract ContentType getContentType();
+    public abstract String getContentType();
 
     @Nullable
     @Override
@@ -56,30 +49,18 @@ public abstract class ChatMessageJson implements ChatMessageModel {
     @Null
     @Nullable
     @Override
-    public abstract Date getTimestamp();
-
-    @Null
-    @Nullable
-    @Override
-    @JsonIgnore
-    public abstract ChatSessionModel getChatSession();
-
-    @Null
-    @Nullable
-    @Override
-    @JsonIgnore
-    public abstract UserModel getSender();
+    public abstract Instant getCreatedAt();
 
     public static ChatMessageJson valueOf(final ChatMessageModel model)
     {
         return ImmutableChatMessageJson.builder()
-                .id(model.getId())
+                .messageId(model.getMessageId())
                 .chatSessionId(model.getChatSessionId())
                 .senderId(model.getSenderId())
                 .contentType(model.getContentType())
                 .content(model.getContent())
                 .url(model.getUrl())
-                .timestamp(model.getTimestamp())
+                .createdAt(model.getCreatedAt())
                 .build();
     }
 

remsfal-core/src/main/java/de/remsfal/core/json/project/ChatSessionJson.java

@@ -1,19 +1,16 @@
 package de.remsfal.core.json.project;
-
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.databind.PropertyNamingStrategies;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonNaming;
 import de.remsfal.core.model.project.ChatSessionModel;
-import de.remsfal.core.validation.UUID;
 import jakarta.annotation.Nullable;
 import jakarta.validation.constraints.Null;
 import org.eclipse.microprofile.openapi.annotations.media.Schema;
 import org.immutables.value.Value;
-
-import java.util.Date;
-import java.util.List;
+import java.time.Instant;
 import java.util.Map;
+import java.util.UUID;
 
 /**
  * @author: Parham Rahmani [parham.rahmani@student.htw-berlin.de]
@@ -24,63 +21,47 @@
 @JsonNaming(PropertyNamingStrategies.SnakeCaseStrategy.class)
 public abstract class ChatSessionJson implements ChatSessionModel {
 
-    @Null
     @Override
-    @UUID
-    public abstract String getId();
+    public abstract UUID getSessionId();
 
-    @Null
     @Nullable
     @Override
-    @UUID
-    public abstract String getProjectId();
+    public abstract UUID getProjectId();
 
-    @Null
     @Nullable
     @Override
-    @UUID
-    public abstract String getTaskId();
+    public abstract UUID getTaskId();
 
     @Nullable
     @Override
-    public abstract TaskType getTaskType();
+    public abstract String getTaskType();
 
     @Nullable
     @Override
     @JsonIgnore
-    public abstract Map<String, ParticipantRole> getParticipants();
+    public abstract Map<java.util.UUID, String> getParticipants();
 
     @Nullable
     @Override
-    public abstract Status getStatus();
-
-
-    @Null
-    @Nullable
-    @Override
-    @JsonIgnore
-    public abstract List<ChatMessageJson> getMessages();
+    public abstract String getStatus();
 
     @Null
     @Nullable
     @Override
-    public abstract Date getCreatedAt();
+    public abstract Instant getCreatedAt();
 
     @Null
     @Nullable
     @Override
-    public abstract Date getModifiedAt();
+    public abstract Instant getModifiedAt();
 
     public static ChatSessionJson valueOf(final ChatSessionModel model) {
         return ImmutableChatSessionJson.builder()
-                .id(model.getId())
+                .sessionId(model.getSessionId())
                 .projectId(model.getProjectId())
                 .taskId(model.getTaskId())
                 .taskType(model.getTaskType())
                 .status(model.getStatus())
-                .messages(model.getMessages().stream()
-                        .map(ChatMessageJson::valueOf)
-                        .toList())
                 .createdAt(model.getCreatedAt())
                 .modifiedAt(model.getModifiedAt())
                 .build();

remsfal-core/src/main/java/de/remsfal/core/model/project/ChatMessageModel.java

@@ -1,36 +1,24 @@
 package de.remsfal.core.model.project;
 
-import de.remsfal.core.model.UserModel;
-
-import java.util.Date;
+import java.time.Instant;
+import java.util.UUID;
 
 /**
- * @author: Parham Rahmani [parham.rahmani@student.htw-berlin.de]
+ * Represents a chat message in Cassandra.
  */
 public interface ChatMessageModel {
 
-    String getId();
-
-    ChatSessionModel getChatSession();
-
-    String getChatSessionId();
-
-    UserModel getSender();
-
-    String getSenderId();
-
+    UUID getChatSessionId(); // Partition key for horizontal scaling
 
-    enum ContentType {
-        TEXT,
-        FILE
-    }
+    UUID getMessageId(); // Unique ID for the message (Clustering column)
 
-    ContentType getContentType();
+    UUID getSenderId(); // ID of the sender
 
-    String getContent();
+    String getContentType(); // Content type (e.g., TEXT, FILE)
 
-    String getUrl();
+    String getContent(); // Text content of the message
 
-    Date getTimestamp();
+    String getUrl(); // File URL if the content type is FILE
 
+    Instant getCreatedAt(); // Timestamp when the message was created
 }

remsfal-core/src/main/java/de/remsfal/core/model/project/ChatSessionModel.java

@@ -1,47 +1,27 @@
 package de.remsfal.core.model.project;
 
-import java.util.Date;
-import java.util.List;
+import java.time.Instant;
 import java.util.Map;
+import java.util.UUID;
 
 /**
- * @author: Parham Rahmani [parham.rahmani@student.htw-berlin.de]
+ * Represents a chat session in Cassandra.
  */
 public interface ChatSessionModel {
 
-    String getId();
+    UUID getProjectId(); // Partition key for horizontal scaling
 
-    String getProjectId();
+    UUID getSessionId(); // Unique ID for the session (Clustering column)
 
-    String getTaskId();
+    UUID getTaskId(); // ID of the associated task
 
-    enum TaskType {
-        DEFECT,
-        TASK
-    }
+    String getTaskType(); // Task type (e.g., DEFECT, TASK)
 
-    TaskType getTaskType();
+    String getStatus(); // Session status (e.g., OPEN, CLOSED, ARCHIVED)
 
-    Map<String, ParticipantRole> getParticipants();
+    Map<UUID, String> getParticipants(); // Map of participant ID to role
 
-    enum ParticipantRole {
-        INITIATOR,
-        HANDLER,
-        OBSERVER
-    }
-
-    List<? extends ChatMessageModel> getMessages();
-
-    Status getStatus();
-
-    enum Status {
-        OPEN,
-        CLOSED,
-        ARCHIVED
-    }
-
-    Date getCreatedAt();
-
-    Date getModifiedAt();
+    Instant getCreatedAt(); // Timestamp when the session was created
 
+    Instant  getModifiedAt(); // Timestamp when the session was last modified
 }