Implement MissingPropertyValidationRule

server/src/providers/validation/MissingPropertyValidation.ts

@@ -0,0 +1,19 @@
+import { Diagnostic, DiagnosticSeverity } from "vscode-languageserver-types";
+import { ValidationContributor, WorkflowDocument } from "../../languageTypes";
+
+export class MissingPropertyValidationRule implements ValidationContributor {
+  constructor(readonly nodePath: string, readonly severity?: DiagnosticSeverity | undefined) {}
+
+  validate(workflowDocument: WorkflowDocument): Promise<Diagnostic[]> {
+    const result: Diagnostic[] = [];
+    const targetNode = workflowDocument.getNodeFromPath(this.nodePath);
+    if (!targetNode) {
+      result.push({
+        message: `Property '${this.nodePath}' is missing`,
+        range: workflowDocument.getDefaultRange(),
+        severity: this.severity,
+      });
+    }
+    return Promise.resolve(result);
+  }
+}