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diff --git a/docs/_posts/2015-04-11-pretty-print-view.md b/docs/_posts/2015-04-11-pretty-print-view.md new file mode 100644 index 0000000..6ea31b1 --- /dev/null +++ b/docs/_posts/2015-04-11-pretty-print-view.md @@ -0,0 +1,39 @@ +--- +layout: post +title: "Pretty-print view in v0.7.3" +date: 2015-04-11 00:00:00 +excerpt: Automatically reformat structured data with "SHIFT+P". +--- + +I wanted to call out the pretty-print feature in the latest release of lnav. +This idea came from a coworker of Suresh who was having a hard time trying to +read some unformatted XML in a log. They wanted the XML pretty-printed and were +hoping that could be done by just piping the message to xmlpp or the like. So, +first we implemented the 'pipe-to' and 'pipe-line-to' commands that will let you +pipe log messages to a command and then display the result inside of lnav. That +worked well enough, but pretty-printing is such a frequent operation that having +to execute a command was kind of a pain. It would also be nice if it worked for +a variety of text, like JSON or Python data. The solution we came up with was to +leverage the existing code for parsing log messages to create a simple +pretty-printer that should work for most data formats. Another benefit is that +the log message does not have to be well-formed for the printer to work, any +leading or trailing garbage shouldn't confuse things. + +As an example, here is a screenshot of the log message with the unformatted XML +text with word-wrapping turned on: + + + +That's not very easy to read and it's hard to figure out the structure of the +message. Now, here is that same message after pressing SHIFT+P to switch to the +pretty-print view of lnav: + + + +The XML text is indented nicely and the usual syntax highlighting is applied. +Also notice that lnav will automatically try to lookup the DNS name for IP +addresses. Overall, I think it's a major improvement over the raw view. + +This is a pretty simple feature but I have found it quite useful in the couple +weeks that it has been implemented. It's so useful that I'm kicking myself for +not having thought of it before. |