Skip to main content

Create an npm-based validator that checks WinCC OA panel files (`.pnl` or `.xml`) against a selected XML schema.

Idea title​

Create an npm-based validator that checks WinCC OA panel files (.pnl or .xml) against a selected XML schema.

Describe your idea​

WinCC OA XML Validator (Research Proposal)

This document describes a separate feature idea that should be tracked as its own issue (not part of the first delivery of the Panel Viewer).

Summary​

Create an npm-based validator that checks WinCC OA panel files (.pnl or .xml) against a selected XML schema.

Key idea:

  • A strict, version-aware validator enables “quality gates” with low effort (translations, allowed colors, required metadata, etc.).

Scope​

Supported WinCC OA versions​

Schemas will be self-maintained only for:

  • WinCC OA 3.20
  • WinCC OA 3.21

Older versions are out of scope due to effort.

Inputs​

The validator should accept:

  • .xml file(s) directly
  • .pnl file(s) by converting to XML first (conversion step is an implementation detail)

Notes:

  • .bak files should be ignored by default.

Output​

The validator should produce:

  • Human-readable CLI output (errors/warnings with file + location when possible)
  • Machine-readable output for CI (e.g., JSON)

Schema strategy​

There is no official panel XML schema, so we will maintain schemas ourselves.

Schema-per-version​

We likely need a schema per WinCC OA version (at least 3.20 and 3.21). Differences should not be hidden; they should be explicit in the schema packages.

User-provided schemas (derived/overrides)​

The validator should support loading schema definitions from:

  • Installed npm package(s)
  • A local filesystem path (so users can check out the schema version they need)

This enables teams to maintain their own “derived” rules without forking the validator.

Proposed repository / package split​

Suggested structure (separate repositories/projects):

  • npm-winccoa-ui-xml-validator

    • CLI and API for validation.
    • Chooses schema based on WinCC OA version or explicit schema path.

  • npm-winccoa-ui-xml-schema (internal “main”, not necessarily public)

    • Staging area to prepare the next schema releases.

  • npm-winccoa-ui-xml-schema-3.20

    • Published schema for WinCC OA 3.20.

  • npm-winccoa-ui-xml-schema-3.21

    • Published schema for WinCC OA 3.21.

CLI UX (draft)​

Minimal commands:

  • validate <file-or-dir>
    • Accepts a file or directory (recursive option).
    • Supports .xml and .pnl.

Flags (draft):

  • --winccoa-version 3.20|3.21
  • --schema <npm-package|path>
  • --recursive
  • --format text|json
  • --fail-on warning|error

Example validations (high value)​

Examples of checks that teams typically want:

  • Translation completeness: required languages exist for all strings.
  • Style rules: allowed colors only, forbidden fonts, minimum contrast, etc.
  • Required metadata: mandatory attributes present.
  • Forbidden content: detect banned scripts/events, banned shapes.
  • Consistency rules: naming conventions for shapes, unique IDs, etc.

Integration with Panel Viewer (later)​

The Panel Viewer can integrate this validator in a later milestone:

  • Run validation on the loaded panel XML snapshot.
  • Surface violations in the tree/details UI.

References (research only)​