Note

This documentation is for a work currently in progress and medjs 1.0 is not yet released.

medjs.utils¶

The medjs.utils provides utility functions for medjs.

To use this package standalone use:

var Utils = require('medjs').utils;
//
// Instead, you can import from medjs like below.
//
// var Medjs = require('medjs');
// var medjs = Medjs.init(['http://localhost:9921']);
// var Utils = medjs.utils;

genHexBuf¶

Utils.genHexBuf(str, bytesLen);

Returns Buffer or Uint8Array from a string with exact length in bytes.

Parameters¶

str - String : The string to generate a buffer.
bytesLen - Number : The target length in bytes.

Returns¶

Buffer|Uint8Array - The result Buffer or Uint8Array.

Example¶

Utils.genHexBuf('12ab', 5);
> <Buffer 00 00 00 12 ab>

isAddress¶

Utils.isAddress(pubKey);

To validate the public key, you can use Utils.isAddress(pubKey).

Note

MediBloc use public key as an address.

Parameters¶

pubKey - String : The public key to validate.

Returns¶

Boolean - It is true if the public key is valid.

Example¶

Utils.isAddress('037d91596727bc522553510b34815f382c2060cbb776f2765deafb48ae528d324b');
> true

isHexadecimal¶

Utils.isHexadecimal(string);

To check the type of the string, you can use Utils.isHexadecimal(string).

Parameters¶

string - String : The string to be validated.

Returns¶

Boolean - It is true if the string is in hexadecimal format.

Example¶

Utils.isHexadecimal('1234567890abcdef');
> true

padLeftWithZero¶

Utils.padLeftWithZero(str, len);

Adds a '0' padding on the left of a string.

Parameters¶

str - String : The string to add padding on the left.
len - Number : The total length of the string should have.

Returns¶

String - The padded string.

Example¶

Utils.padLeftWithZero('12ab', 10);
> '00000012ab'

randomHex¶

Utils.randomHex(length);

To get a random seed number, you can use Utils.randomHex(length).

Parameters¶

length - Number : (optional) The byte size of a random seed number. If not given, 16 is used.

Returns¶

String - The random number in hexadecimal format.

Example¶

Utils.randomHex();
> 'baab6c02ce89592e03b8f9bbea8eb553'

sha3¶

Utils.sha3(msg);

To hash messages, you can use Utils.sha3(msg). This function uses SHA3_256 algorithm and returns 256bit hexadecimal string.

Parameters¶

msg - String|Object|Number : The message is stringified.

Returns¶

String - The hash string in hexadecimal format.

Example¶

Utils.sha3('Hello MediBloc!!!');
> '25cd0631574c642502446ace0c9c46811f1404e39d6d892771b346724851dd7e'

sha3Stream¶

Utils.sha3Stream(stream);

To hash stream, you can use Utils.sha3Stream(stream). This function uses SHA3_256 algorithm and returns 256bit hexadecimal string.

Parameters¶

stream - Stream : The readable stream.

Returns¶

String - The hash string in hexadecimal format.

Example¶

Utils.sha3Stream(stream); // some readable stream
> '8a1fb1154b917c9e3df4370008e0bf34c6de6babb1592225371731a71a9b2e13'