dk-checker-remove-extraneous

Utility for removing extraneous params via ts-interface-checker

[!WARNING]
It's fine if you use this library from NPM package with a static versioning in case you want it for some pet-project or to test it's capabilities.

But for production use it's strongly recommended to create a fork, because I do not write Changelogs and may break / add some functionality without notice.

Installation

Add dk-checker-remove-extraneous to package.json and install.

Usage

This lib works with ts-interface-checker. You can use dk-file-generator for suitable validators generation.

Add to places where validators are used, ex. for API response:

import _ from 'lodash';
import { createCheckers } from 'ts-interface-checker';
import { removeExtraneousParams } from 'dk-checker-remove-extraneous';

import * as apiValidatorsRaw from 'validators/api';

const apiValidators = _.mapValues(apiValidatorsRaw, (value) => createCheckers(value));

function validateResponse(
  apiName: string,
  response: any
) {
  const validators = apiValidators[apiName];

  try {
    // Check mandatory params, throw on error
    validators.TypeResponse.check(response);

    // Clear extraneous params for compatibility (mutable operation)
    removeExtraneousParams({
      data: response,
      validators: validators.TypeResponse, // TypeResponse is a checker, use your name
      logger: ({ extraneousPaths }) => {
        console.warn(`Omitted extraneous ${JSON.stringify(extraneousPaths)} for "api/${apiName}"`);
      },
    });

    // Now response is carefully checked and extraneous params are removed,
    // it's safe to use it as expected
    return response;
  } catch (error) {
    throw new Error(`validateResponse: ${error.message} for "api/${apiName}"`);
  }
}

// Use in fetch
fetch(url)
  .then(fetchResponse => fetchResponse.json())
  .then(response => validateResponse('someApi', response))
  .then(validatedResponse => someLogic(validatedResponse))
  .catch((error) => someErrorHandler(error));