Logging

Logging for ew-cmaf-ingest

Logging

To provide context to each log message, structured logging is used. By dividing the log data into fields of name-value pairs, the logs become more coherent and are better suited for processing by external tools.

Log messages related to a specific channel include a log field named chName (channel name), which can be used to filter messages for specific channels.

Log formats

From the command line, by specifying -logformat parameters, ew-cmaf-ingest supports the following logging formats: consolepretty, consolejson, or journald. To disable logging, set it to discard. The default logging format is consolejson.

Format setup example:

$ ./ew-cmaf-ingest -logformat consolejson

consolepretty logs to standard output (stdout) in a human-readable format. Each log line starts with the date and the log message, followed by context-dependent log fields:
2025-01-03T15:17:58+07:00 INF Wrote segment chName=testpic_2s name=867946138.cmfv nrBytes=37863 trName=V300
consolejson logs to stdout using a JSON object for each message:
{“level”:“info”,“chName”:“testpic_2s”,“trName”:“A48”,“seqNr”:867946183,“oldestNr”:867946176,“latestNr”:867946183, …}
When switching the -logformat to journald, ew-cmaf-ingest will send logs to journald following the journald format, with field names in uppercase. Examples:
To see entries with the channel name testpic_2s:
```
$ journalctl -u ew-cmaf-ingest CHNAME=testpic_2s -o verbose
```
To see entries with the stream name A48:
```
$ journalctl -u ew-cmaf-ingest NAME=A48 -o verbose
```

Using the verbose output includes all available name-value fields. Without this option, only the log message is printed. The field named JSON contains the original structured log message as sent by the service. To filter out only thisfield, use --output-fields=JSON. Note that this requires a systemd version of at least 236.

$ journalctl -u ew-cmaf-ingest --output-fields=JSON CHNAME=testpic_2s

To continuously monitor the service:

$ journalctl -fu ew-cmaf-ingest

Log levels

At startup, default value is info. The log level can be changed by posting a form field named level to the loglevel endpoint on the ew-cmaf-ingest server: sh $ curl -F level=debug <ew-cmaf-ingest-server>:<server-port>/loglevel

The available log levels and their corresponding systemd priority values are listed below:

Log level  Systemd priority
trace      7
debug      7
info       6
warn       4
error      3
fatal      2
panic      0

To see all error and warning messages using journalctl, run:

$ journalctl -u ew-cmaf-ingest PRIORITY=3 PRIORITY=4

To see the current log level, use a GET request:

$ curl <ew-cmaf-ingest-server>:<server-port>/loglevel

Messages with a higher level than the configured one will not be logged.