extract-params

Extract Params

Installation

npm install extract-params --save

Then, in your app:

var extractParams = require('extract-params').extractParams;
// or
var extractParamsInFirstMatch = require('extract-params').extractParamsInFirstMatch;

API

• extractParams(str, pattern)
• extractParamsInFirstMatch(str, patterns)

extractParams(str, pattern)

Tests whether str matches the given parameterized pattern, and returns a key-value object of parameters and their values in case of a successful match.

pattern parameters must be in the following format: :camelCase

Match must occur from the first character of str in order to be considered successful (see examples below).

If match is not successful, extractParams returns null.

Example 1

var params = extractParams(
  '/users/123/friends/456/photo',
  '/users/:userId/friends/:friendId/photo'
);

/* 
  Returns:
    {
      userId: '123',
      friendId: '456'
    }
*/

Example 2

var params = extractParams(
  '/home/users/123/friends/456/photo',
  '/users/:userId/friends/:friendId/photo'
);

/* 
  Returns:
    null
      
  because `str` matches `pattern`,
  but not from the first character of `str`.
*/

extractParamsInFirstMatch(str, patterns)

Tests whether str matches one of the parameterized patterns. If none of the patterns match, extractParamsInFirstMatch returns null. Otherwise, it returns the matching pattern and its parameters.

Example 1

var params = extractParamsInFirstMatch(
  '/users/123',
  [
    '/users/:userId/friends/:friendId/photo',
    '/users/:userId/friends/:friendId',
    '/users/:userId/friends',
    '/users/:userId',
    '/users'
  ]
);

/* 
  Returns:
    {
      pattern: '/users/:userId',
      params: {
        userId: '123'
      }
    }
*/

Example 2

var params = extractParamsInFirstMatch(
  '/users/123/subscriptions',
  [
    '/users/:userId/friends/:friendId/photo',
    '/users/:userId/friends/:friendId',
    '/users/:userId/friends',
    '/users/:userId',
    '/users'
  ]
);

/* 
  Returns:
    null
    
  because none of the patterns match.
*/

Running Tests

npm test

License

MIT