Shell scripts that runs anonymous Apex with Salesforce CLI and filters out command output to only display time stamp and debug messages

run-apex.sh

#!/bin/bash
# Shell scripts that runs anonymous Apex with Salesforce CLI and filters out command output to only display time stamp and debug messages
# Know limitation: the script doesn't support multiline log messages (it will only display the first line)

# Get Apex file path from parameter or ask for it
filePath=""
if [ "$#" -eq 1 ]; then
  filePath="$1"
else
  echo "Apex file path:"
  read filePath
fi

# Run anonymous Apex with the Salesforce CLI
OUTPUT=$(sfdx force:apex:execute -f "$filePath")
EXIT_CODE="$?"

# Check Salesforce CLI exit code
if [ "$EXIT_CODE" -eq 0 ]; then
    # Check for Apex runtime error
    APEX_ERRORS=$(echo "$OUTPUT" | grep 'Error: ')
    if [ "$APEX_ERRORS" != '' ]; then
      # Log errors
      echo "Apex runtime error:"
      echo "$APEX_ERRORS"
      EXIT_CODE=-1;
    else
      # Keep debug log lines only
      OUTPUT=$(echo "$OUTPUT" | grep 'USER_DEBUG')
      # Simplify debug log: keep time stamp, line number and message only
      OUTPUT=$(echo "$OUTPUT" | sed -E 's,([0-9]{2}:[0-9]{2}:[0-9]{2}\.[0-9]+) \([0-9]+\)\|USER_DEBUG\|\[([0-9]+)\]\|DEBUG\|(.*),\1\tLine \2\t\3,')
      echo "$OUTPUT"
    fi
else
    # Salesforce CLI error
    echo "Salesforce CLI failed to execute anonymous Apex:"
    echo "$OUTPUT"
fi
echo ""
exit $EXIT_CODE

temp.apex

// Sample anonymous Apex file for trying out run-apex.sh

System.debug('Hello');
System.debug('World!');

Get the shell script and the sample anonymous Apex file.
Run the script with sh run-apex.sh. This runs the anonymous Apex from temp.apex and outputs a log with simplified debug messages only:

./run-apex.sh
10:38:38.18     Line 3     Hello
10:38:38.18     Line 4     World!

Known limitation: the script does not support multi-line debug log messages. It will only show the first line of the log message.