Logging

CUE Zipline generates log output using the standard Python logging subsystem. The log output is designed to provide information for troubleshooting integration issues.

Four different levels of log message are generated by CUE Zipline:

Level	Description
`ERROR`	Generated for events that are considered to be processing errors, such as when a back-end service responds with an error to a request that is expected to succeed.
`WARNING`	Generated for less serious adverse events, such as when a back-end service responds with an error to a request that is not expected to always succeed.
`INFO`	Generated for normal events, describing what CUE Zipline is doing. When handling a content item update, for example, `INFO` messages will be logged when the event is received, when the items required to process the request are resolved, when back-end requests are sent and so on.
`DEBUG`	More detailed messages describing how CUE Zipline handles events. `DEBUG` messages may be logged, for example, for each of the individual requests sent to a back-end service while resolving a content item for processing.

You can control which of these messages are actually written to file, where they are sent, how long they are kept and so on by configuring the logging system.