Automatic Generation of Regular Expression Based on Log Line Data

In one aspect, a regular expression is automatically generated based on user input for fields that are desired to be extracted from log lines. The input may be received by user through an interface provided by a machine such as a controller. The input may identify one or more fields within a log line that should be extracted. Multiple instances of potential regular expression portions may be generated based on the user input, and different portions are combined together to determine if they achieve the desired extraction. Once a complete regular expression is generated based on user input, a user may provide additional input to identify examples or counterexamples of log line fields that satisfy or don't satisfy the user's intended extraction.