How to use Post Install Script to enable Quotes and Order object?

Yes it is possible.

HttpRequest request = new HttpRequest();
request = new HttpRequest();
request.setEndpoint('https://ap2.salesforce.com/services/Soap/m/31.0');
request.setMethod('POST');
request.setHeader('Content-Type', 'text/xml');
request.setHeader('SOAPAction', 'update');
String b = '<?xml version="1.0" encoding="UTF-8"?>';
b += '<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">';
b += '<soapenv:Header>';
b += '<ns1:SessionHeader soapenv:mustUnderstand="0" xmlns:ns1="http://soap.sforce.com/2006/04/metadata">';
b += '<ns1:sessionId>' + UserInfo.getSessionId() + '</ns1:sessionId>';
b += '</ns1:SessionHeader>';
b += '</soapenv:Header>';
b += '<soapenv:Body>';

b += '<update xmlns="http://soap.sforce.com/2006/04/metadata">';
b += '<UpdateMetadata>';
b += '<currentName>QuoteSettings</currentName>';

b += '<metadata xsi:type="ns2:QuoteSettings" xmlns:ns2="http://soap.sforce.com/2006/04/metadata">';

b += '<fullName>QuoteSettings</fullName>';
b += '<enableQuote>true</enableQuote>';

b += '</metadata>';
b += '</UpdateMetadata>';
b += '</update>';
b += '</soapenv:Body>';
b += '</soapenv:Envelope>';
request.setBody(b);
request.setCompressed(false);

String body = (new Http()).send(request).getBody();
system.debug('response'+body);

• This reply was modified 10 years, 7 months ago by  Abhinav.