Comment by teraflop

Comment by teraflop a day ago

11 replies

The point is not to sanitize known strings like "OutOfMemoryException". The point is to sanitize or (preferably) escape any untrusted data that gets logged, so that it won't be confused for something else.

swyx a day ago

i think GP's point is how would you even sanitize the string "OutOfMemoryException" which presumably comes from a trusted system

i guess demanding "Structured logs for everything or bust" is the answer? (i'm not a big o11y guy so pardon me if this is obvious)

  • noisem4ker a day ago

    "o11y" stands for "observability".

    Numeronyms are evil and we should stop using them.

    • j1elo a day ago

      Thanks. My mind started running the random string generator given those restrictions, like a puzzle game. But had no idea of what it meant until you wrote it. Who invented that stupid idea and thought it would be a good one?

      • swyx a day ago

        because its easily googlable.

        counter point - people are going to use them, better to expose newbies early and often and then everyone is better off

        shorthands will always be in demand. we used to say “horseless carriage”, then “automobile”, then “car”. would you rather use Light amplification by stimulated emission of radiation or just “laser”s? etc

        in the new york times? sure, spell out observability. but on HN? come on. the term is 7 years old and is used all over the site. it’s earned it

    • ramon156 a day ago

      You're right, avoiding them gives better a11y

  • PhilipRoman a day ago

    Low tech example: escape all newlines in user supplied strings, then add a known prefix to all user supplied data (let's say a double hashtag ##, but anything else works too). When you want to search logs for strings coming from your system, remove/ignore everything after the marker.

    It all comes down to understanding whether the intersection of two grammars is empty.

    • jethro_tell a day ago

      The difficulty here is that in the example above, it's unlikely, given any amount of scale, that the two people were on the same team. They were doing different things with the same data and probably didn't know what the other was doing.

      Sure you could add a convention to your 'how to log' doc that specifies that all user input should be tagged with double '#' but who reads docs until things break? convention is a shitty way to make things work.

      There's 100 ways that you could make this work correctly. Only restarting on a much more specific string, i.e. including the app name in the log line etc . . . but that's all just reducing the likely hood that you get burned.

      I've also written a OOM-Killer.sh myself, I'm not above that, but it's one of those edge cases that's impossible to do correctly, which is why parsing and acting on log data generally considered and anti-pattern.