Input Validation for Construction Data
Overview
Validate incoming construction data before processing to catch errors early. Domain-specific validation rules for estimates, schedules, BIM exports, and field data.
Validation Framework
Core Validator Class
from dataclasses import dataclass, field
from typing import List, Dict, Any, Callable, Optional
from enum import Enum
import re
from datetime import datetime
class ValidationSeverity(Enum):
ERROR = "error" # Must fix, blocks processing
WARNING = "warning" # Should review, allows processing
INFO = "info" # FYI, no action needed
@dataclass
class ValidationIssue:
field: str
message: str
severity: ValidationSeverity
value: Any = None
suggestion: str = None
@dataclass
class ValidationResult:
is_valid: bool
issues: List[ValidationIssue] = field(default_factory=list)
def add_error(self, field: str, message: str, value: Any = None, suggestion: str = None):
self.issues.append(ValidationIssue(field, message, ValidationSeverity.ERROR, value, suggestion))
self.is_valid = False
def add_warning(self, field: str, message: str, value: Any = None, suggestion: str = None):
self.issues.append(ValidationIssue(field, message, ValidationSeverity.WARNING, value, suggestion))
def add_info(self, field: str, message: str, value: Any = None):
self.issues.append(ValidationIssue(field, message, ValidationSeverity.INFO, value))
@property
def errors(self) -> List[ValidationIssue]:
return [i for i in self.issues if i.severity == ValidationSeverity.ERROR]
@property
def warnings(self) -> List[ValidationIssue]:
return [i for i in self.issues if i.severity == ValidationSeverity.WARNING]
def to_report(self) -> str:
lines = ["VALIDATION REPORT", "=" * 50]
lines.append(f"Status: {'PASSED' if self.is_valid else 'FAILED'}")
lines.append(f"Errors: {len(self.errors)}, Warnings: {len(self.warnings)}")
lines.append("")
for issue in self.issues:
icon = "❌" if issue.severity == ValidationSeverity.ERROR else "⚠️" if issue.severity == ValidationSeverity.WARNING else "ℹ️"
lines.append(f"{icon} [{issue.field}] {issue.message}")
if issue.suggestion:
lines.append(f" Suggestion: {issue.suggestion}")
return "\n".join(lines)Cost Estimate Validation
class CostEstimateValidator:
"""Validate cost estimate inputs."""
# Typical cost ranges per CSI division ($/SF)
TYPICAL_RANGES = {
'03': (15, 45), # Concrete
'04': (8, 25), # Masonry
'05': (12, 35), # Metals
'06': (5, 20), # Wood/Plastics
'07': (8, 30), # Thermal/Moisture
'08': (15, 50), # Openings
'09': (10, 40), # Finishes
'22': (8, 25), # Plumbing
'23': (12, 40), # HVAC
'26': (10, 35), # Electrical
}
def validate(self, estimate_data: Dict[str, Any]) -> ValidationResult:
result = ValidationResult(is_valid=True)
# Required fields
self._validate_required_fields(estimate_data, result)
# Line item validation
if 'line_items' in estimate_data:
self._validate_line_items(estimate_data['line_items'], result)
# Total validation
self._validate_totals(estimate_data, result)
# Cost range validation
if 'gross_area' in estimate_data:
self._validate_cost_ranges(estimate_data, result)
return result
def _validate_required_fields(self, data: dict, result: ValidationResult):
required = ['project_name', 'estimate_date', 'line_items', 'total']
for field in required:
if field not in data or data[field] is None:
result.add_error(field, f"Required field '{field}' is missing")
def _validate_line_items(self, items: list, result: ValidationResult):
for i, item in enumerate(items):
# Check for negative values
if item.get('quantity', 0) < 0:
result.add_error(f"line_items[{i}].quantity", "Quantity cannot be negative", item.get('quantity'))
if item.get('unit_cost', 0) < 0:
result.add_error(f"line_items[{i}].unit_cost", "Unit cost cannot be negative", item.get('unit_cost'))
# Check for missing descriptions
if not item.get('description'):
result.add_warning(f"line_items[{i}].description", "Line item missing description")
# Check for valid CSI code
if item.get('csi_code'):
if not re.match(r'^\d{2}\s?\d{2}\s?\d{2}$', item['csi_code']):
result.add_warning(f"line_items[{i}].csi_code", f"Invalid CSI code format: {item['csi_code']}", suggestion="Use format: XX XX XX")
# Check for zero amounts
amount = item.get('quantity', 0) * item.get('unit_cost', 0)
if amount == 0:
result.add_warning(f"line_items[{i}]", "Line item has zero amount")
def _validate_totals(self, data: dict, result: ValidationResult):
if 'line_items' not in data or 'total' not in data:
return
calculated = sum(
item.get('quantity', 0) * item.get('unit_cost', 0)
for item in data['line_items']
)
declared = data['total']
variance = abs(calculated - declared)
if variance > 0.01:
result.add_error("total", f"Total mismatch: calculated {calculated:.2f}, declared {declared:.2f}", variance)
def _validate_cost_ranges(self, data: dict, result: ValidationResult):
gross_area = data['gross_area']
for item in data.get('line_items', []):
csi_div = item.get('csi_code', '')[:2]
if csi_div in self.TYPICAL_RANGES:
amount = item.get('quantity', 0) * item.get('unit_cost', 0)
cost_per_sf = amount / gross_area if gross_area > 0 else 0
low, high = self.TYPICAL_RANGES[csi_div]
if cost_per_sf < low * 0.5 or cost_per_sf > high * 2:
result.add_warning(
f"line_items[{item.get('description', 'Unknown')}]",
f"Cost ${cost_per_sf:.2f}/SF outside typical range ${low}-${high}/SF for Division {csi_div}",
cost_per_sf,
"Review unit costs and quantities"
)Schedule Validation
class ScheduleValidator:
"""Validate schedule/planning inputs."""
def validate(self, schedule_data: Dict[str, Any]) -> ValidationResult:
result = ValidationResult(is_valid=True)
# Required fields
self._validate_required_fields(schedule_data, result)
# Task validation
if 'tasks' in schedule_data:
self._validate_tasks(schedule_data['tasks'], result)
self._validate_dependencies(schedule_data['tasks'], result)
self._validate_resources(schedule_data['tasks'], result)
return result
def _validate_required_fields(self, data: dict, result: ValidationResult):
required = ['project_name', 'start_date', 'tasks']
for field in required:
if field not in data:
result.add_error(field, f"Required field '{field}' is missing")
def _validate_tasks(self, tasks: list, result: ValidationResult):
task_ids = set()
for i, task in enumerate(tasks):
# Check for duplicate IDs
task_id = task.get('id')
if task_id in task_ids:
result.add_error(f"tasks[{i}].id", f"Duplicate task ID: {task_id}")
task_ids.add(task_id)
# Check dates
start = task.get('start_date')
end = task.get('end_date')
if start and end:
try: