print no match found only once after iterating all entires from input file in shell script

Question

I know there is a way to do it but I can't seem to remember now. I have a small shell script which has a simple while loop and it iterates through a CSV file and has an if else loop inside it. The problem is for every line the while loop iterates the if else statement prints a no match found until it finds a match or it keeps printing no match until end of file is reached. I wanted to check how can I print no-match found only once after iterating through the entire file. Here is my sample code below

while IFS=, read -r path servicename app text1 text2 text3;
do
    text1="$key1"
    text2="$key2"
    text3="$key3"

    if [[ $servicename = $SERVICE_NAME ]];
    then
        if [[ $ENV = "sb" ]]; then
            ID="$key1"
        elif [[ $ENV = "lb" ]]; then
            ID="$key2"
        elif [[ $ENV = "dev" ]]; then
            ID="$key3"
        fi
    else
        echo "no match found"
    fi
done < $input_file

sample data that is used in the iteration

path,service,app,text1,text2,text3
path/of/service1,servicename1,appname,key1,key2,key3
path/of/service2,servicename2,appname,key1,key2,key3
path/of/service3,servicename3,appname,key1,key2,key3
path/of/service4,servicename4,appname,key1,key2,key3
path/of/service5,servicename5,appname,key1,key2,key3

Answer 1

Use a variable that keeps track if a match was found or not, and display the message at the end only.

Like this:

#!/bin/bash

SERVICE_NAME="blablabla"
ENV="blablabla"
input_file="input.txt"

match_found="no"

while IFS=, read -r path servicename app text1 text2 text3
do
    text1="$key1"
    text2="$key2"
    text3="$key3"

    if [[ "$servicename" == "$SERVICE_NAME" ]]
    then
        match_found="yes"
        if [[ "$ENV" == "sb" ]]
        then
            ID="$key1"
        elif [[ "$ENV" == "lb" ]]
        then
            ID="$key2"
        elif [[ "$ENV" == "dev" ]]
        then
            ID="$key3"
        fi
    fi
done < "$input_file"

if [[ "$match_found" == "no" ]]
then
    printf "No match found\n"
fi

Another couple modifications:

• used == in the if conditions to check if text matches
• all variables use is double quoted
• I had to set a couple global variables to some bogus values to test my answer. When you ask a question, you should provide a complete minimal sample.