Webhook to Discord for New Day

[troubleshootme]

I have my server start, server shutdown, player joined, player death, and player disconnect hooks working but I am really struggling with the new day webhook. On new day, the server log shows : Mar 13 14:04:45 supervisord: valheim-server 03/13/2023 14:04:45: Time 341662.25998408, day:189 nextm:342270.000010729 skipspeed:50.6450022207573

I have the following in my stack.env file and at the moment, the hook works but my regex capture is no good (I only know a little regex) and discord message is the whole line: Starting Day 03/13/2023 00:20:17: Time 336308.279902585, day:186 nextm:336870.000010729 skipspeed:46.8100090119988

I am just trying to capture the day number (\d+) and print "Starting day $1"

The env lines: VALHEIM_LOG_FILTER_REGEXP_Day=day:(\d+) ON_VALHEIM_LOG_FILTER_REGEXP_Day='{ read l; l=${l// (\d+) /}; msg="Starting Day $l"; curl -sfSL -X POST -H "Content-Type: application/json" -d "{\"username\":\"Valheim\",\"content\":\"$msg\"}" "$DISCORD_WEBHOOK"; }'

If possible, can someone break down what each part does?

[ncraig419]

ON_VALHEIM_LOG_FILTER_REGEXP_Day='{ read l; l=${l// (\d+) /}; msg="Starting Day $l"; curl -sfSL -X POST -H "Content-Type: application/json" -d "{\"username\":\"Valheim\",\"content\":\"$msg\"}" "$DISCORD_WEBHOOK"; }' lets look at each step. read l; - this reads the whole line from the log Time 341662.25998408, day:189 nextm:342270.000010729 skipspeed:50.6450022207573

l=${l// (\d+) /}; this takes that log line and does a string replace using bash parameter expansion (If there are two slashes separating parameter and pattern, all matches of pattern are replaced with string.) since we didnt find the literal string ' (\d+) ' nothing is replaced Time 341662.25998408, day:189 nextm:342270.000010729 skipspeed:50.6450022207573

msg="Starting Day $l"; now we pass our variable I into the new string and get Starting Day Time 341662.25998408, day:189 nextm:342270.000010729 skipspeed:50.6450022207573

`curl -sfSL -X POST -H "Content-Type: application/json" -d "{\"username\":\"Valheim\",\"content\":\"$msg\"}" $DISCORD_WEBHOOK"; Finally, we post that string to the discord hook as content, with the webhook posting as username 'Valheim'

---

So what I think you may be looking for is ON_VALHEIM_LOG_FILTER_REGEXP_Day='{ read l; l=${l// (\d+) /}; msg="Starting Day $l"; curl -sfSL -X POST -H "Content-Type: application/json" -d "{\"username\":\"Valheim\",\"content\":\"$msg\"}" "$DISCORD_WEBHOOK"; }' if you want to stick with bash parameter expansion, you'll want to use the cut functions so first read the line read l; "Time 341662.25998408, day:189 nextm:342270.000010729 skipspeed:50.6450022207573"

then cut the first half off at the word day (including the colon) l=${l#*day:}; "189 nextm:342270.000010729 skipspeed:50.6450022207573"

then cut the second half off at nextm l=${l%%nextm*}; "189 "

remove extra spaces l=${l//[[:space:]]/}; "189"

msg="Starting Day $l"; now we pass our variable I into the new string and get "Starting Day 189"

`curl -sfSL -X POST -H "Content-Type: application/json" -d "{\"username\":\"Valheim\",\"content\":\"$msg\"}" $DISCORD_WEBHOOK"; Finally, we post that string to the discord hook as content, with the webhook posting as username 'Valheim'

so to put it all together, ON_VALHEIM_LOG_FILTER_REGEXP_Day='{ read l; l=${l#*day:}; l=${l%%nextm*}; l=${l//[[:space:]]/}; msg="Starting Day $l"; curl -sfSL -X POST -H "Content-Type: application/json" -d "{\"username\":\"Valheim\",\"content\":\"$msg\"}" "$DISCORD_WEBHOOK"; }'

its by no means clean, but it gets you where you want, without using awk, send, cut or regex capture groups

[troubleshootme]

@ncraig419 That's exactly what I was looking for, thanks so much for sharing your knowledge!