cleanup impls

bookshop/test/dynamic-constraints/validate.js

@@ -0,0 +1,33 @@
+const cds = require('@sap/cds')
+const $super = { validate: cds.validate, skip(){} }
+
+
+/**
+ * Quick and dirty implementation for cds.validate() using db-level constraints.
+ */
+cds.validate = function (x, pk, ...columns) {
+
+  // Delegate to base impl of cds.validate() for standard input validation
+  if (!_is_constraints(x)) return $super.skip (...arguments)
+
+  // Support subject refs to base entities as arguments
+  if (x?.ref) [ x, pk ] = [ x.ref +'.constraints', pk.ID||pk ]
+
+  // Run the constraints check query
+  const constraints = cds.model.definitions[x] || cds.error `No such constraints view: ${x}`
+  return SELECT.one.from (constraints, pk, columns.length && columns)
+
+  // Collect and throw errors, if any
+  .then (checks => {
+    const failed = {}; for (let c in checks) {
+      if (c in constraints.keys) continue
+      if (c[0] == '_') continue
+      if (checks[c]) failed[c] = checks[c]
+    }
+    if (Object.keys(failed).length) throw cds.error `Invalid input: ${failed}`
+  })
+}
+
+
+// Helpers
+const _is_constraints = x => x.ref || x.is_entity || typeof x === 'string'