getDIP15ExtendedKey

Usage: keychain.getDIP15ExtendedKey(userUniqueId, contactUniqueId, index, accountIndex = 0, type = 'HDPrivateKey')

Description: Return a DIP15 Extended Key of a 2-contacts relationship

Parameters:

parameters	type	required	Description
userUniqueId	string	yes	Current DashPay unique UserID
contactUniqueId	string	yes	Contact DashPay unique UserID
index	number	no(=0)	the key index to derivate to
accountIndex	number	no(=0)	the wallet account index from which to derivate
type	string	no (default:HDPrivateKey)	type of returned keys. one of: ['HDPrivateKey','HDPublicKey'].

Returns : {HDPrivateKey|HDPublicKey} (of path: m/9'/5'/15'/accountIndex'/userId'/contactID'/index on mainnet or m/9'/1'/15'/... on testnet)

Example:

// m/9'/5'/15'/0'/0x555d3854c910b7dee436869c4724bed2fe0784e198b8a39f02bbb49d8ebcfc3a'/0xa137439f36d04a15474ff7423e4b904a14373fafb37a41db74c84f1dbb5c89b5'/0

const userUniqueId = '0x555d3854c910b7dee436869c4724bed2fe0784e198b8a39f02bbb49d8ebcfc3a';
const contactUniqueId = '0xa137439f36d04a15474ff7423e4b904a14373fafb37a41db74c84f1dbb5c89b5';

const DIP15ExtPrivKey_0 = keychain2.getDIP15ExtendedKey(userUniqueId, contactUniqueId, 0, 0, 'HDPrivateKey');
const { privateKey } = DIP15ExtPrivKey_0; //fac40790776d171ee1db90899b5eb2df2f7d2aaf35ad56f07ffb8ed2c57f8e60