Linux - parsing data, what language to use - linux

Question

I am looking to parse data out of a 'column' based format. I am running into issues where I feel I am 'hacking' bash/awk commands to pull the strings and numbers. If the numbers/text come in different formats then the script might fail unexpectedly and I will have errors.
Data:
RSSI (dBm): -86 Tx Power: 0
RSRP (dBm): -114 TAC: 4r5t (12341)
RSRQ (dB): -10 Cell ID: efefwg (4261431)
SINR (dB): 2.2
My method:
Using bash and awk
#!/bin/bash
DATA_OUTPUT=$(get_data)
RSSI=$(echo "${DATA_OUTPUT}" | awk '$1 == "RSSI" {print $3}')
RSRP=$(echo "${DATA_OUTPUT}" | awk '$1 == "RSRP" {print $3}')
RSRQ=$(echo "${DATA_OUTPUT}" | awk '$1 == "RSRQ" {print $3}')
SINR=$(echo "${DATA_OUTPUT}" | awk '$1 == "SINR" {print $3}')
TX_POWER=$(echo "${DATA_OUTPUT}" | awk '$4 == "Tx" {print $6}')
echo "$SINR"
echo ">$SINR<"
However the output of the above comes out very strange.
2.2 # thats fine!
<2.2 # what??? expecting >4.6<
Little things like this make me question using awk and bash to parse the data. Should I use C++ or some other language? Or is there a better way of doing this?
Thank you

Answer 1

This should be your starting point (the match() can be simplified or removed if your input data is tab-separated or fixed width fields):
$ cat file
RSSI (dBm): -86 Tx Power: 0
RSRP (dBm): -114 TAC: 4r5t (12341)
RSRQ (dB): -10 Cell ID: efefwg (4261431)
SINR (dB): 2.2
.
$ cat tst.awk
{
tail = $0
while ( match(tail,/[^:]+:[[:space:]]+[^[:space:]]+[[:space:]]*([^[:space:]]*$)?/) )
{
nvPair = substr(tail,RSTART,RLENGTH)
sub(/ \([^)]+\):/,":",nvPair) # remove (dB) or (dBm)
sub(/:[[:space:]]+/,":",nvPair) # remove spaces after :
sub(/[[:space:]]+$/,"",nvPair) # remove trailing spaces
split(nvPair,tmp,/:/)
name2value[tmp[1]] = tmp[2] # name2value["RSSI"] = "-86"
tail = substr(tail,RSTART+RLENGTH)
}
}
END {
for (name in name2value) {
value = name2value[name]
printf "%s=\"%s\"\n", name, value
}
}
.
$ awk -f tst.awk file
Tx Power="0"
RSSI="-86"
TAC="4r5t (12341)"
Cell ID="efefwg (4261431)"
RSRP="-114"
RSRQ="-10"
SINR="2.2"
Hopefully it's clear that in the above script after the match() loop you can simply say things like print name2value["Tx Power"] to print the value of that key phrase.
If your data was created in DOS, run dos2unix or tr -d '^M' on it first, where ^M means a literal control-M character.

Answer 2

Your data contains DOS-style \r\n line endings. When you do this
echo ">$SINR<"
The actual output is actually
>4.6\r<
The carriage return sends the cursor back to the start of the line.
You can do this:
DATA_OUTPUT=$(get_data | sed 's/\r$//')
But instead of parsing the output over and over, I'd rewrite like this:
while read -ra fields; do
case ${fields[0]} in
RSSI) rssi=${fields[2]};;
RSRP) rsrp=${fields[2]};;
RSPQ) rspq=${fields[2]};;
SINR) sinr=${fields[2]};;
esac
if [[ ${fields[3]} == "Tx" ]]; then tx_power=${fields[5]}; fi
done < <(get_data | sed 's/\r$//' )