+1 for the RegexR - i wrote some more complex expressions with it, it has a great interactive and visual explainer to help you out as you progress. The final expression can be copied as is from there into NiFi, no special escapes needed, etc.
Thanks. I'm a novice nifi's user.
I've got in a "extract text" processor this property "grok" below.
I find nifi regex to have less options. The same regex ( [\.]conf ) in my case to find a configuration file works from outside Nifi.
But on putting this pattern in Nifi ListHDFS processor , File Pattern will not match and the file is never pulled.
Any idea why this would happen ?