Setup spotlight project

.stoplight/custom-functions/oasSchema.js

@@ -0,0 +1,88 @@
+import traverse from 'json-schema-traverse';
+import { schema as schemaFn } from '@stoplight/spectral-functions';
+import { createRulesetFunction } from '@stoplight/spectral-core';
+import { oas2, oas3_1, extractDraftVersion, oas3_0 } from '@stoplight/spectral-formats';
+import { isPlainObject, pointerToPath } from '@stoplight/json';
+
+function rewriteNullable(schema, errors) {
+  for (const error of errors) {
+    if (error.keyword !== 'type') continue;
+    const value = getSchemaProperty(schema, error.schemaPath);
+    if (isPlainObject(value) && value.nullable === true) {
+      error.message += ',null';
+    }
+  }
+}
+
+export default createRulesetFunction(
+  {
+    input: null,
+    options: {
+      type: 'object',
+      properties: {
+        schema: {
+          type: 'object',
+        },
+      },
+      additionalProperties: false,
+    },
+  },
+  function oasSchema(targetVal, opts, context) {
+    const formats = context.document.formats;
+
+    let { schema } = opts;
+
+    let dialect = 'draft4';
+    let prepareResults;
+
+    if (!formats) {
+      dialect = 'auto';
+    } else if (formats.has(oas3_1)) {
+      if (isPlainObject(context.document.data) && typeof context.document.data.jsonSchemaDialect === 'string') {
+        dialect = extractDraftVersion(context.document.data.jsonSchemaDialect) ?? 'draft2020-12';
+      } else {
+        dialect = 'draft2020-12';
+      }
+    } else if (formats.has(oas3_0)) {
+      prepareResults = rewriteNullable.bind(null, schema);
+    } else if (formats.has(oas2)) {
+      const clonedSchema = JSON.parse(JSON.stringify(schema));
+      traverse(clonedSchema, visitOAS2);
+      schema = clonedSchema;
+      prepareResults = rewriteNullable.bind(null, clonedSchema);
+    }
+
+    return schemaFn(
+      targetVal,
+      {
+        ...opts,
+        schema,
+        prepareResults,
+        dialect,
+      },
+      context,
+    );
+  },
+);
+
+const visitOAS2 = schema => {
+  if (schema['x-nullable'] === true) {
+    schema.nullable = true;
+    delete schema['x-nullable'];
+  }
+};
+
+function getSchemaProperty(schema, schemaPath) {
+  const path = pointerToPath(schemaPath);
+  let value = schema;
+
+  for (const fragment of path.slice(0, -1)) {
+    if (!isPlainObject(value)) {
+      return;
+    }
+
+    value = value[fragment];
+  }
+
+  return value;
+}