Validation Rules Builder
Business Case
Problem Statement
Construction data quality challenges:
- Inconsistent naming conventions
- Invalid cost codes and WBS
- Missing or malformed data
- Non-compliant BIM elements
Solution
Rule-based validation engine using RegEx and logic rules to ensure data quality across construction systems.
Technical Implementation
import re
from typing import Dict, Any, List, Optional, Callable
from dataclasses import dataclass, field
from enum import Enum
from datetime import date
class RuleType(Enum):
REGEX = "regex"
RANGE = "range"
ENUM = "enum"
CUSTOM = "custom"
REQUIRED = "required"
DATE = "date"
REFERENCE = "reference"
class Severity(Enum):
ERROR = "error"
WARNING = "warning"
INFO = "info"
@dataclass
class ValidationResult:
field: str
is_valid: bool
message: str
severity: Severity
value: Any = None
@dataclass
class ValidationRule:
name: str
field: str
rule_type: RuleType
pattern: str = ""
min_value: float = None
max_value: float = None
allowed_values: List[Any] = field(default_factory=list)
custom_func: Callable = None
severity: Severity = Severity.ERROR
message: str = ""
enabled: bool = True
class ValidationRulesBuilder:
"""Build and execute validation rules for construction data."""
# Pre-defined patterns for construction data
PATTERNS = {
'wbs_code': r'^[0-9]{2}\.[0-9]{2}\.[0-9]{2}(\.[0-9]{2})?$',
'cost_code': r'^[A-Z]{1,3}-[0-9]{3,6}$',
'activity_id': r'^[A-Z]{1,3}[0-9]{4,6}$',
'drawing_number': r'^[A-Z]{1,2}-[0-9]{3}-[A-Z0-9]{2,4}$',
'specification_section': r'^[0-9]{2}\s?[0-9]{2}\s?[0-9]{2}(\.[0-9]{2})?$',
'level_name': r'^(Level|L|FL)\s?[-_]?\s?([0-9]{1,3}|B[0-9]|R|G|M)$',
'grid_line': r'^[A-Z]\.?[0-9]?$|^[0-9]{1,2}\.?[A-Z]?$',
'revision': r'^[A-Z]$|^[0-9]{1,2}$|^Rev\.?\s?[A-Z0-9]+$',
'date_iso': r'^\d{4}-\d{2}-\d{2}$',
'email': r'^[\w\.-]+@[\w\.-]+\.\w+$',
'phone': r'^\+?[0-9]{1,3}[-.\s]?[0-9]{3,4}[-.\s]?[0-9]{4}$',
}
def __init__(self):
self.rules: List[ValidationRule] = []
self.custom_patterns: Dict[str, str] = {}
def add_regex_rule(self,
name: str,
field: str,
pattern: str,
message: str = "",
severity: Severity = Severity.ERROR) -> 'ValidationRulesBuilder':
"""Add regex validation rule."""
self.rules.append(ValidationRule(
name=name,
field=field,
rule_type=RuleType.REGEX,
pattern=pattern,
message=message or f"Field '{field}' does not match pattern",
severity=severity
))
return self
def add_range_rule(self,
name: str,
field: str,
min_value: float = None,
max_value: float = None,
message: str = "",
severity: Severity = Severity.ERROR) -> 'ValidationRulesBuilder':
"""Add numeric range validation rule."""
self.rules.append(ValidationRule(
name=name,
field=field,
rule_type=RuleType.RANGE,
min_value=min_value,
max_value=max_value,
message=message or f"Field '{field}' out of range [{min_value}, {max_value}]",
severity=severity
))
return self
def add_enum_rule(self,
name: str,
field: str,
allowed_values: List[Any],
message: str = "",
severity: Severity = Severity.ERROR) -> 'ValidationRulesBuilder':
"""Add enumeration validation rule."""
self.rules.append(ValidationRule(
name=name,
field=field,
rule_type=RuleType.ENUM,
allowed_values=allowed_values,
message=message or f"Field '{field}' must be one of: {allowed_values}",
severity=severity
))
return self
def add_required_rule(self,
name: str,
field: str,
message: str = "",
severity: Severity = Severity.ERROR) -> 'ValidationRulesBuilder':
"""Add required field validation rule."""
self.rules.append(ValidationRule(
name=name,
field=field,
rule_type=RuleType.REQUIRED,
message=message or f"Field '{field}' is required",
severity=severity
))
return self
def add_custom_rule(self,
name: str,
field: str,
func: Callable[[Any], bool],
message: str = "",
severity: Severity = Severity.ERROR) -> 'ValidationRulesBuilder':
"""Add custom validation function."""
self.rules.append(ValidationRule(
name=name,
field=field,
rule_type=RuleType.CUSTOM,
custom_func=func,
message=message or f"Field '{field}' failed custom validation",
severity=severity
))
return self
def add_pattern(self, name: str, pattern: str):
"""Add custom pattern for reuse."""
self.custom_patterns[name] = pattern
def use_pattern(self,
rule_name: str,
field: str,
pattern_name: str,
message: str = "",
severity: Severity = Severity.ERROR) -> 'ValidationRulesBuilder':
"""Use pre-defined or custom pattern."""
pattern = self.custom_patterns.get(pattern_name) or self.PATTERNS.get(pattern_name)
if not pattern:
raise ValueError(f"Pattern '{pattern_name}' not found")
return self.add_regex_rule(rule_name, field, pattern, message, severity)
def validate_record(self, record: Dict[str, Any]) -> List[ValidationResult]:
"""Validate a single record against all rules."""
results = []
for rule in self.rules:
if not rule.enabled:
continue
value = record.get(rule.field)
result = self._apply_rule(rule, value)
results.append(result)
return results
def validate_records(self, records: List[Dict[str, Any]]) -> Dict[str, Any]:
"""Validate multiple records and return summary."""
all_results = []
error_count = 0
warning_count = 0
for i, record in enumerate(records):
record_results = self.validate_record(record)
for result in record_results:
if not result.is_valid:
result_dict = {
'record_index': i,
'field': result.field,
'message': result.message,
'severity': result.severity.value,
'value': result.value
}
all_results.append(result_dict)
if result.severity == Severity.ERROR:
error_count += 1
elif result.severity == Severity.WARNING:
warning_count += 1
return {
'total_records': len(records),
'valid_records': len(records) - len(set(r['record_index'] for r in all_results if r['severity'] == 'error')),
'error_count': error_count,
'warning_count': warning_count,
'issues': all_results
}
def _apply_rule(self, rule: ValidationRule, value: Any) -> ValidationResult:
"""Apply single validation rule."""
if rule.rule_type == RuleType.REQUIRED:
is_valid = value is not None and value != "" and value != []
return ValidationResult(
field=rule.field,
is_valid=is_valid,
message="" if is_valid else rule.message,
severity=rule.severity,
value=value
)
# Skip other validations if value is None/empty
if value is None or value == "":
return ValidationResult(
field=rule.field,
is_valid=True,
message="",
severity=rule.severity,
value=value
)
if rule.rule_type == RuleType.REGEX:
is_valid = bool(re.match(rule.pattern, str(value)))
elif rule.rule_type == RuleType.RANGE:
try:
num_value = float(value)
is_valid = True
if rule.min_value is not None and num_value < rule.min_value:
is_valid = False
if rule.max_value is not None and num_value > rule.max_value:
is_valid = False
except (ValueError, TypeError):
is_valid = False
elif rule.rule_type == RuleType.ENUM:
is_valid = value in rule.allowed_values
elif rule.rule_type == RuleType.CUSTOM:
try:
is_valid = rule.custom_func(value)
except Exception:
is_valid = False
else:
is_valid = True
return ValidationResult(
field=rule.field,
is_valid=is_valid,
message="" if is_valid else rule.message,
severity=rule.severity,
value=value
)
def get_rules_summary(self) -> List[Dict]:
"""Get summary of all rules."""
return [{
'name': r.name,
'field': r.field,
'type': r.rule_type.value,
'severity': r.severity.value,
'enabled': r.enabled
} for r in self.rules]
# Construction-specific validators
class ConstructionValidators:
"""Pre-built validators for construction data."""
@staticmethod
def wbs_validator() -> ValidationRulesBuilder:
"""Validator for WBS codes."""
return (ValidationRulesBuilder()
.add_required_rule("wbs_required", "wbs_code")
.use_pattern("wbs_format", "wbs_code", "wbs_code", "Invalid WBS format (expected: XX.XX.XX)")
)
@staticmethod
def cost_item_validator() -> ValidationRulesBuilder:
"""Validator for cost items."""
return (ValidationRulesBuilder()
.add_required_rule("code_required", "cost_code")
.add_required_rule("desc_required", "description")
.use_pattern("code_format", "cost_code", "cost_code")
.add_range_rule("quantity_positive", "quantity", min_value=0)
.add_range_rule("unit_cost_positive", "unit_cost", min_value=0)
.add_enum_rule("unit_valid", "unit", ["EA", "LF", "SF", "CY", "TON", "HR", "LS"])
)
@staticmethod
def schedule_activity_validator() -> ValidationRulesBuilder:
"""Validator for schedule activities."""
def dates_valid(record):
start = record.get('start_date')
end = record.get('end_date')
if start and end:
return start <= end
return True
return (ValidationRulesBuilder()
.add_required_rule("id_required", "activity_id")
.add_required_rule("name_required", "activity_name")
.use_pattern("id_format", "activity_id", "activity_id")
.add_range_rule("duration_positive", "duration", min_value=0)
.add_range_rule("progress_range", "percent_complete", min_value=0, max_value=100)
)
@staticmethod
def bim_element_validator() -> ValidationRulesBuilder:
"""Validator for BIM elements."""
return (ValidationRulesBuilder()
.add_required_rule("guid_required", "element_guid")
.add_required_rule("type_required", "element_type")
.add_required_rule("level_required", "level")
.use_pattern("level_format", "level", "level_name", severity=Severity.WARNING)
.add_enum_rule("status_valid", "status",
["New", "Existing", "Demolished", "Temporary"])
)Quick Start
# Create validator
validator = ValidationRulesBuilder()
# Add rules
validator.add_required_rule("id_required", "item_id")
validator.use_pattern("wbs_valid", "wbs_code", "wbs_code")
validator.add_range_rule("cost_range", "total_cost", min_value=0, max_value=10000000)
validator.add_enum_rule("status_valid", "status", ["Active", "Completed", "Cancelled"])
# Validate records
records = [
{"item_id": "001", "wbs_code": "01.02.03", "total_cost": 50000, "status": "Active"},
{"item_id": "", "wbs_code": "invalid", "total_cost": -100, "status": "Unknown"}
]
results = validator.validate_records(records)
print(f"Valid: {results['valid_records']}/{results['total_records']}")
print(f"Errors: {results['error_count']}, Warnings: {results['warning_count']}")Common Use Cases
1. Cost Data Validation
cost_validator = ConstructionValidators.cost_item_validator()
results = cost_validator.validate_records(cost_items)2. Schedule Validation
schedule_validator = ConstructionValidators.schedule_activity_validator()
results = schedule_validator.validate_records(activities)3. BIM Element Validation
bim_validator = ConstructionValidators.bim_element_validator()
results = bim_validator.validate_records(elements)Resources
- DDC Book: Chapter 2.6 - Data Quality Requirements
- Website: https://datadrivenconstruction.io