Message Logging

Records channel chat messages in NDJSON (Newline Delimited JSON) format to files. This feature is available when channel chat is enabled and is turned on by default.

Configuration

# config.yml
features:
  channelChat:
    enabled: true
    messageLogging:
      enabled: true
      retentionDays: 30
      maxFileSizeMB: 100

Setting Key	Default	Description
enabled	true	Enable message logging
retentionDays	30	Number of days to retain log files (0 for unlimited retention)
maxFileSizeMB	100	Maximum size of a single log file (MB)

Log File Format

Log files are saved in the plugins/LunaticChat/logs/ directory. Each line is a single JSON object.

File Naming

channel-messages-YYYY-MM-dd.json

When the file size exceeds maxFileSizeMB, a new file with a suffix is created.

channel-messages-2026-04-05.json       # Base file
channel-messages-2026-04-05-1.json     # On size overflow
channel-messages-2026-04-05-2.json     # On further overflow

Entry Format

Each line has the following JSON structure.

{
  "timestamp": "2026-04-05T14:23:45.123Z",
  "playerId": "550e8400-e29b-41d4-a716-446655440000",
  "playerName": "Steve",
  "channelId": "general",
  "message": "Hello everyone!"
}

Field	Type	Description
timestamp	String	ISO 8601 timestamp (UTC)
playerId	String	Player UUID
playerName	String	Player display name
channelId	String	ID of the channel the message was sent to
message	String	Message content

File Rotation

• Daily rotation: A new file is created when the date changes
• Size rotation: Switches to a suffixed file when maxFileSizeMB is exceeded
• Automatic cleanup: Log files older than the number of days specified by retentionDays are automatically deleted (no deletion when set to 0)

Usage Examples

Since the format is NDJSON, you can easily filter and aggregate logs using tools like jq.

Extract Messages from a Specific Channel

jq 'select(.channelId == "general")' channel-messages-2026-04-05.json

Extract Messages from a Specific Player

jq 'select(.playerName == "Steve")' channel-messages-2026-04-05.json

Count Messages by Channel

jq -s 'group_by(.channelId) | map({channel: .[0].channelId, count: length})' channel-messages-2026-04-05.json