validation-pipeline

name	validation-pipeline
description	Valideringspipeline med ValidationResult sealed class, FileValidator, LineValidationRules, LineValidator og FileParser for fixed-width copybook-filer

Validation & File Parsing Patterns

Valideringsmønstre: ValidationResult sealed class, FileValidator, LineValidationRules, LineValidator og FileParser for fixed-width filer.

Validation is a two-phase pipeline: file-level (FileValidator) then line-level (LineValidator + LineValidationRules). Both produce ValidationResult. File errors move the whole file to /inbound/feilfiler; line errors mark individual lines as VALIDERINGSFEIL_AV_LINJE_I_FIL and keep them in the DB.

ValidationResult sealed class

All validation functions return ValidationResult. Never throw exceptions for expected business-rule failures — return ValidationResult.Error instead:

sealed class ValidationResult {
    data class Success(val kravLinjer: List<KravLinje>) : ValidationResult()
    data class Error(val messages: List<Pair<String, String>>) : ValidationResult()
}

messages is a list of (errorKey, humanReadableMessage) pairs. The errorKey identifies the failure type (used as the Slack header/tag key); the human-readable message includes the field value and line number.

Sub-files

• See file-validation.md for FileValidator patterns (file-level rules, error keys, pattern).
• See line-validation.md for LineValidationRules (per-line business rules) and LineValidator (orchestration).
• See file-parser.md for FileParser (fixed-width copybook parser, data classes, byte positions, extraction helpers).

Boundaries

✅ Always

• Return ValidationResult from all validation functions — never throw for business-rule failures
• Use buildList {} to accumulate all errors before returning (do not short-circuit on first error)
• Include line number and field values in every error message string
• Set status = Status.KRAV_IKKE_SENDT.value on valid lines, Status.VALIDERINGSFEIL_AV_LINJE_I_FIL.value on invalid lines
• Call slackService.sendErrors() exactly once at the end of each validation pass
• Use LineValidationRules.errorDate as the sentinel value for unparseable date fields
• Replace \uFFFD → Ø in kravKode after extraction

⚠️ Ask First

• Adding new validation rules to LineValidationRules (may affect SKE acceptance rate)
• Changing byte offsets in FileParser (format is fixed by the upstream sender)
• Changing which Avsender values trigger fagsystemId validation

🚫 Never

• Throw from individual check* functions in LineValidationRules (return null for OK, String for error)
• Drop invalid lines from the returned list — always return all lines with status set
• Persist line errors after the status field has already been set to VALIDERINGSFEIL_AV_LINJE_I_FIL
• Modify any KravLinje fields other than status during validation