Network Validation

This guide covers PyPtP's validation system for checking network data quality. The validator detects issues like disconnected elements, invalid coordinates, missing presentations, and data inconsistencies.

Full Example

View the complete code: 04_validation.py

Running Validation

Basic Usage

from pyptp import NetworkMV, configure_logging
from pyptp.validator import CheckRunner, Severity

configure_logging(level="INFO")

# Load network
network = NetworkMV.from_file("network.vnf")

# Run all validators
runner = CheckRunner(network)
report = runner.run()

The CheckRunner executes all registered validation checks and returns a ValidationReport containing any issues found.

Quick Summary

from pyptp.ptp_log import logger

logger.info("Validation: {}", report.summary())

The summary() method returns a concise string like "3 errors, 12 warnings".

Understanding Severity Levels

# Count issues by severity
error_count = sum(1 for issue in report.issues if issue.severity == Severity.ERROR)
warning_count = sum(1 for issue in report.issues if issue.severity == Severity.WARNING)

logger.info("  Errors: {}", error_count)
logger.info("  Warnings: {}", warning_count)

Severity Definitions

Level	Meaning	Action Required
ERROR	Network will not function correctly	Must fix before use
WARNING	Potential issue or suboptimal configuration	Review and fix if relevant
INFO	Informational note	Optional improvements

Common Error Types

Issue	Description
Missing node reference	Branch references a node that doesn't exist
Disconnected element	Element not connected to any node
Invalid GUID	Malformed or duplicate GUID
Missing presentation	Element has no visual representation

Common Warnings

Issue	Description
Coordinate mismatch	Branch corner doesn't align with node position
Unused node	Node with no connected elements
Duplicate name	Multiple elements share the same name

Inspecting Issues

Iterate Critical Issues

for issue in report.issues:
    if issue.severity == Severity.ERROR:
        logger.error("ERROR: {}", issue.message)
        logger.error("  Element: {} {}", issue.object_type, issue.object_id)

Issue Properties

Property	Description
severity	Severity.ERROR, WARNING, or INFO
code	Machine-readable issue identifier
message	Human-readable description
object_type	Element type (e.g., "Node", "Line")
object_id	GUID of the affected element

Filter by Issue Code

# Find all coordinate mismatch issues
coord_issues = [
    issue for issue in report.issues
    if issue.code == "BRANCH_CORNER_MISMATCH"
]

Exporting Reports

JSON Export

from pathlib import Path

Path("validation_report.json").write_text(
    str(report.to_json()),
    encoding="utf-8"
)

The JSON format is useful for:

• Automated CI/CD pipelines
• Integration with issue tracking systems
• Historical comparison of validation results

Programmatic Access

# Check if network passes validation
is_valid = error_count == 0
logger.info("Network valid: {}", is_valid)

# Use in automation
if not is_valid:
    raise ValueError(f"Network has {error_count} validation errors")

Validation in Workflows

Pre-Save Validation

def save_if_valid(network, path):
    """Only save network if it passes validation."""
    report = CheckRunner(network).run()
    errors = sum(1 for i in report.issues if i.severity == Severity.ERROR)

    if errors > 0:
        logger.error("Cannot save: {} errors found", errors)
        return False

    network.save(path)
    logger.info("Network saved to {}", path)
    return True

CI/CD Integration

import sys

def validate_network(vnf_path):
    """Exit with error code if validation fails."""
    network = NetworkMV.from_file(vnf_path)
    report = CheckRunner(network).run()

    errors = sum(1 for i in report.issues if i.severity == Severity.ERROR)

    if errors > 0:
        for issue in report.issues:
            if issue.severity == Severity.ERROR:
                print(f"ERROR: {issue.message}")
        sys.exit(1)

    print("Validation passed")
    sys.exit(0)

Complete Example

"""Validate network data quality."""

from pathlib import Path

from pyptp import NetworkMV, configure_logging
from pyptp.ptp_log import logger
from pyptp.validator import CheckRunner, Severity

configure_logging(level="INFO")

# Load network
network = NetworkMV.from_file("network.vnf")

# Run validation
runner = CheckRunner(network)
report = runner.run()

# Check results
logger.info("Validation: {}", report.summary())

# Count issues by severity
error_count = sum(1 for issue in report.issues if issue.severity == Severity.ERROR)
warning_count = sum(1 for issue in report.issues if issue.severity == Severity.WARNING)
logger.info("  Errors: {}", error_count)
logger.info("  Warnings: {}", warning_count)

# Show critical issues
for issue in report.issues:
    if issue.severity == Severity.ERROR:
        logger.error("ERROR: {}", issue.message)
        logger.error("  Element: {} {}", issue.object_type, issue.object_id)

# Export report
Path("validation_report.txt").write_text(str(report.to_json()), encoding="utf-8")

# Check if network is valid
is_valid = error_count == 0
logger.info("Network valid: {}", is_valid)

Next Steps

Corner Validation

Understanding coordinate validation

Presentations

Ensure valid presentations

Modify Networks

Fix validation issues