function validateErrorResponseSchema()

in functions/error-response.js [22:135]

• 90 lines of code
• 24 McCabe index (conditional complexity)

function validateErrorResponseSchema(errorResponseSchema, pathToSchema) {
  const errors = [];
  // The error response MUST be a single JSON object.
  if (!errorResponseSchema.properties) {
    errors.push({
      message: 'Error response schema must be an object schema.',
      path: pathToSchema,
    });
    return errors;
  }
  // This object MUST have a name/value pair named "error." The value MUST be a JSON object.
  if (!errorResponseSchema.properties.error || !errorResponseSchema.properties.error.properties) {
    errors.push({
      message: 'Error response schema should contain an object property named `error`.',
      path: [...pathToSchema, 'properties', 'error'],
    });
    return errors;
  }

  // The `error` object should be required (always present)

  if (!errorResponseSchema.required?.includes?.('error')) {
    errors.push({
      message: 'The `error` property in the error response schema should be required.',
      path: [...pathToSchema, 'required'],
    });
  }

  const errorSchema = errorResponseSchema.properties.error;
  const pathToErrorSchema = [...pathToSchema, 'properties', 'error'];

  // Spectral message dedup will drop all but first message with the same path, so we need
  // combine messages when they would wind up with the same path.

  const hasCode = !!errorSchema.properties.code;
  const hasMessage = !!errorSchema.properties.message;

  if (!hasCode && hasMessage) {
    errors.push({
      message: 'Error schema should contain `code` property.',
      path: [...pathToErrorSchema, 'properties'],
    });
  } else if (hasCode && !hasMessage) {
    errors.push({
      message: 'Error schema should contain `message` property.',
      path: [...pathToErrorSchema, 'properties'],
    });
  } else if (!hasCode && !hasMessage) {
    errors.push({
      message: 'Error schema should contain `code` and `message` properties.',
      path: [...pathToErrorSchema, 'properties'],
    });
  }

  if (hasCode && errorSchema.properties.code.type !== 'string') {
    errors.push({
      message: 'The `code` property of error schema should be type `string`.',
      path: [...pathToErrorSchema, 'properties', 'code', 'type'],
    });
  }

  if (hasMessage && errorSchema.properties.message.type !== 'string') {
    errors.push({
      message: 'The `message` property of error schema should be type `string`.',
      path: [...pathToErrorSchema, 'properties', 'message', 'type'],
    });
  }

  // Check if schema defines `code` and `message` as required

  if (['code', 'message'].every((prop) => !errorSchema.required?.includes?.(prop))) {
    // Either there is no required or it is missing both properties, so report both missing
    errors.push({
      message: 'Error schema should define `code` and `message` properties as required.',
      path: [...pathToErrorSchema, 'required'],
    });
  } else if (!errorSchema.required.includes('code')) {
    errors.push({
      message: 'Error schema should define `code` property as required.',
      path: [...pathToErrorSchema, 'required'],
    });
  } else if (!errorSchema.required.includes('message')) {
    errors.push({
      message: 'Error schema should define `message` property as required.',
      path: [...pathToErrorSchema, 'required'],
    });
  }

  // The value for the "target" name/value pair is ... the name of the property in error
  if (!!errorSchema.properties.target && errorSchema.properties.target.type !== 'string') {
    errors.push({
      message: 'The `target` property of the error schema should be type `string`.',
      path: [...pathToErrorSchema, 'properties', 'target'],
    });
  }

  // The value for the "details" name/value pair MUST be an array of JSON objects
  if (!!errorSchema.properties.details && !isArraySchema(errorSchema.properties.details)) {
    errors.push({
      message: 'The `details` property of the error schema should be an array.',
      path: [...pathToErrorSchema, 'properties', 'details'],
    });
  }

  // The value for the "innererror" name/value pair MUST be an object
  if (!!errorSchema.properties.innererror && !isObjectSchema(errorSchema.properties.innererror)) {
    errors.push({
      message: 'The `innererror` property of the error schema should be an object.',
      path: [...pathToErrorSchema, 'properties', 'innererror'],
    });
  }

  return errors;
}