Logs of the app can be access in the app monitor in the section Logs. There you will be able to
see what’s going on in your app, which is very important when you need to diagnose issues or there
is something odd in the app.
In the logs you will see logs generated by the system as well as logs done using the Javascript API
method like sys.logs.info() or sys.logs.error().
Logs are sorted from the oldest to the newest. If you scroll down more logs will be loaded automatically until no more logs are found.
One thing to keep in mind is that there is a limit on the size used by logs (see Logs and alerts). Once the amount of logs reaches that size, logs will be rotated and older ones will be lost.
Filtering logs
Logs can be filtered by log level (info, warn, error), time and a search string.
When filtering by a time period you should introduce a time duration in the next input box, like
5m (last five minutes), 2h (last two hours) or 3d (last three days). If you need more
precision you can use a date range.
Search string will match all log items where the string is found. You can search by Regular expressions by typing regex: REGEX
replacing REGEX with the regex to filter logs. Example, with regex: .*GET.* you can filter those logs that are GET access.
Show IP
There is a flag called Show IP. If it is set, the IP where the request comes from will be displayed
in the logs (if available as the event could have been generated internally).
Show locations
There is a flag called Show location. If it is set, the location (city/state/country) where the request comes from will be displayed
in the logs (if available as the event could have been generated internally).
External only
If this flag is set, only logs related to the interaction of the app with external systems will be shown. For example REST API calls or endpoints interactions.
UI only
If this flag is set, only logs of request coming from the UI will be shown.
Getting more information
Some logs provide more information that is not displayed in the log line because it would be too
much and would be hard to read. In those cases you will see a small button with the label More info
that when you click it you can see more details.
For example in an endpoint event you can see the data of sent by the endpoint, and when there is an error you will be able to see where in the code the error was thrown as well as the stack trace, which is very useful information when you are debugging.
Finally, when jobs are executed there is a button with the label Go to job that will take you
to the job details.
Context
When you filter logs, you will see a button called Context next to each log line. If you click
there you will see the logs before and after that log. This will help you to figure out the context
of the log without having to remove the filters you have set.
Alerts
Alerts are based on logs. For example in production you might want to get an alert when an error or a warning is logged.
You can do that in the app monitor or app builder in the section Environment settings > Logs and alerts.
You can find more information here.
Download logs
It is possible to export app logs to a compressed JSON format file based on current filtering selection. The log entries file to export will be generated in a background task. Once the task has finished the download of the file will start automatically.