Verify Script Output Content: Validate Output Quality

Your script runs successfully, but you need to verify the output contains expected content. Learn how to validate script output programmatically.

Why Output Validation Matters

Scripts can run successfully but produce wrong or missing output:

Database query returns empty result set
API call succeeds but response missing required fields
File processing completes but output file missing content
Report generation runs but produces empty output
Data transformation completes but format is wrong

Exit code alone doesn't verify output quality. You need to check output content.

How to Verify Output Content

After running your script, verify the output contains expected content. Check for required strings, validate JSON structure, verify file contents, or count output lines.

Bash Example: Check Output Contains String

#!/bin/bash
OUTPUT=$(./generate-report.sh)
# Get output validation data
HAS_EXPECTED_CONTENT=0
OUTPUT_LENGTH=${#OUTPUT}
if echo "$OUTPUT" | grep -q "Report generated successfully"; then
  HAS_EXPECTED_CONTENT=1
fi
# Single ping with output validation data in payload
# In DeadManPing panel: set validation rules:
#   - "has_expected_content" == 1
#   - "output_length" > 0
# Panel will automatically detect if output is invalid
curl -X POST "https://deadmanping.com/api/ping/report-job?has_expected_content=$HAS_EXPECTED_CONTENT&output_length=$OUTPUT_LENGTH"

Python Example: Validate JSON Output

import subprocess
import json
import requests
result = subprocess.run(['./api-fetch.sh'], capture_output=True, text=True)
output = result.stdout
# Parse output and extract data for payload
is_valid_json = True
has_required_fields = False
try:
  data = json.loads(output)
  required_fields = ['status', 'data', 'timestamp']
  has_required_fields = all(field in data for field in required_fields)
except json.JSONDecodeError:
  is_valid_json = False
# Single ping with output validation data in payload
# In DeadManPing panel: set validation rules:
#   - "is_valid_json" == True
#   - "has_required_fields" == True
# Panel will automatically detect if output is invalid
requests.post(f"https://deadmanping.com/api/ping/api-job?is_valid_json={is_valid_json}&has_required_fields={has_required_fields}")

Monitoring Output Validation

After adding output validation to your scripts, use a dead man switch to monitor whether validation completed successfully. If your script detects invalid output and exits with error code, the ping never arrives, and you get an alert.

Working Examples

See complete, working code examples in our GitHub repository:

View Examples on GitHub →

Start Verifying Script Output

DeadManPing monitors whether your output validation completes. Set up monitoring in 2 minutes, get alerts when output is invalid.

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Learn more about cron job monitoring and troubleshooting:

Verify Script Output Content: Validate Output Quality

Why Output Validation Matters

How to Verify Output Content

Bash Example: Check Output Contains String

Python Example: Validate JSON Output

Monitoring Output Validation

Working Examples

Start Verifying Script Output

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