Salesforce to Salesforce Integration using Composite API :

Send Multiple Requests Using Composite

Executes a series of REST API requests in a single call. You can use the output of one request as the input to a subsequent request. The response bodies and HTTP statuses of the requests are returned in a single response body. The entire series of requests counts as a single call toward your API limits.

The requests in a composite call are called subrequests. All subrequests are executed in the context of the same user. In a subrequest’s body, you specify a reference ID that maps to the subrequest’s response. You can then refer to the ID in the url or body fields of later subrequests by using a JavaScript-like reference notation.

For example, the following composite request body includes two subrequests. The first creates an account and designates the output as refAccount. The second creates a contact parented under the new account by referencing refAccount in the subrequest body.

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Salesforce

Apex Trigger:

trigger OnContact on Contact (after update) {

    

    if(trigger.isAfter && Trigger.isUpdate){

        

         for(Contact cont : Trigger.new) { 

               

            if(trigger.oldMap.get(cont.id).primary_contact__c!=cont.primary_contact__c && cont.Primary_Contact__c==true){

                ConnectToSalesforceRestApi.run(cont.id);

            }

         }

    }

}

Apex class:

public class ConnectToSalesforceRestApi {

    

    @Future(callout=true)

    public static void run(string contactid){

        String endpoint='https://kreya2-dev-ed.develop.my.salesforce.com/services/oauth2/token';

        // or use this endpoint for a sandbox org:

        // String endpoint='https://test.salesforce.com/services/oauth2/token';

        String username = 'amulhai@dev2.com';

        String password = 'reset12QRGoMnURJNigP0m0okBi6K';

        String CONSUMER_KEY = '3MVG9fe4g9fhX0E5Ejj.OX6.kBWke.eCBDa8RpIqaJlx.HhxRXUQYtmxJhs0VP6cPtJmXphhKEofq.qSFAyuu';

        String CONSUMER_SECRET = '5FC04C75E3C32C3E5F05FB1C661804E70F50D73B48194681BB35D9464D9CF2B3';

        

        Httprequest request = new HttpRequest();

        request.setMethod('POST');

        request.setHeader('Content-Type','application/x-www-form-urlencoded');

        

        request.setBody(

            'grant_type=password' +

            '&client_id=' + CONSUMER_KEY +

            '&client_secret=' + CONSUMER_SECRET +

            '&username=' + username +

            '&password=' + password

        );

        request.setEndpoint(endpoint);

        

        Http http = new Http();

        HttpResponse response;

        String accessToken;

        

        try {

            response = http.send(request);

            System.debug('body: ' + response.getBody());

            accessToken = parseResponseForAccessToken(response.getBody());

        } catch(System.CalloutException error){

            System.debug('error: ' + error);

        }

        

        System.debug('access token: ' + accessToken);

        // be careful as the following line will print sensitive credentials to the logs

        // System.debug(UserInfo.getOrganizationId().substring(0, 15) + ' ' +  UserInfo.getSessionId().substring(15));

        

        query(accessToken);

        PushContactToDev2(contactid,accessToken);

        //PushAccountToDev2(contactid,accessToken);

    }

    

    private static String parseResponseForAccessToken(String responseBody) {

        String accessToken;

        

        JSONParser parser = JSON.createParser(responseBody);

        while (parser.nextToken() != null) {

            if ((parser.getCurrentToken() == JSONToken.FIELD_NAME) && (parser.getText() == 'access_token')) {

                parser.nextToken();

                accessToken = parser.getText();

            }

        }

        return accessToken;

    }

    

    private static void PushContactToDev2(String contactid,String accessToken){

        Account acc=new Account();

        Contact cont=new Contact();

        if(contactid!=''){

            list<contact> lstContact=[Select id, firstName, Lastname, Email,Phone,AccountId from contact where id=:contactid];

            string accountId='';

            if(lstContact.size()>0){

                accountId=lstContact[0].AccountId;

                cont=lstContact[0];

            }

            list<Account> lstAccount=[Select id, name, POS__c, Contracted_System__c, Credit_Status__c, AccountNumber from account where id=:accountId];

            

            if(lstAccount.size()>0){

                acc=lstAccount[0];

            }

        }

        String endpoint = 'https://kreya2-dev-ed.develop.my.salesforce.com/services/data/v56.0/composite/';

        String JsonData='';

        string strAccountNumber=acc.AccountNumber;

        string POS=acc.POS__c;

        string ContractedSystem=acc.Contracted_System__c;

        string AccName=acc.Name;

        string CreditStatus=acc.Credit_Status__c;

        string contfirstName=cont.firstName;

        string contLastName=cont.LastName;

        string contEmail=cont.Email;

        string contPhone=cont.Phone;

            

        Httprequest request = new HttpRequest();

        Http http = new Http();

        HttpResponse response;

        

        JsonData=JSONBodyData(strAccountNumber,POS,ContractedSystem,CreditStatus,contfirstName,contLastName,contEmail,contPhone,AccName);

        

        request.setEndpoint(endpoint);

        request.setMethod('POST');

        

        // we can use either of the two below lines for content Type.

        // request.setHeader('Content-Type','application/json');

        request.setHeader('Content-Type','application/json');

        request.setHeader('Authorization','Bearer ' + accessToken);

        request.setBody(JsonData);

        response = http.send(request);

        

        System.debug('body: ' + response.getBody());

        

        

    }

    

    public static string JSONBodyData(string strAccountNumber,string POS, string ContractedSystem

                                 , string CreditStatus

                                 , string contfirstName

                                 , string contLastName

                                 , string contEmail

                                 , string contPhone

                                 , string AccName) {

String json= '{'+

'    "allOrNone" : true,'+

'    "compositeRequest": [{'+

'        "method": "PATCH",'+

'        "url": "/services/data/v56.0/sobjects/Account/AccountNumber_External_id__c/' + strAccountNumber + '",' + 

'        "referenceId": "NewAccount",'+

'        "body": {'+

'            "POS__c": "'+ POS + '",' +

'            "Contracted_System__c": "'+ ContractedSystem + '",' +

        '            "Name": "'+ AccName + '",' +

'            "Credit_Status__c": "'+ CreditStatus + '"' +

'        }'+

'    },{'+

'        "method" : "PATCH",'+

'        "url" : "/services/data/v56.0/sobjects/Contact/Email_External_Id__c/' + contEmail + '",'+

'        "referenceId" : "newContact",'+

'        "body" : {'+

'            "firstName" : "'+ contfirstName + '",' +

'            "LastName" : "'+ contLastName + '",' +

'            "Email" : "'+ contEmail + '",' +

'            "Phone" : "'+ contPhone + '",' +

'            "AccountId" : "@{NewAccount.id}"'+

'        }'+

'    }]'+

'}';

                                     

                                     return json;

}

    

    

   /* private static void PushAccountToDev2(String contactid,String accessToken){

        String endpoint = 'https://kreya2-dev-ed.develop.my.salesforce.com/services/data/v42.0/query/?q=SELECT+name+from+account+limit+1';

        Httprequest request = new HttpRequest();

        Http http = new Http();

        HttpResponse response;

        

        request.setEndpoint(endpoint);

        request.setMethod('GET');

        

    }

*/

    

    

    private static void query(String accessToken) {

        // this endpoint allows us to append a SOQL query to retrieve specific data

        // see the documentation for a complete list of endpoints

        String endpoint = 'https://kreya2-dev-ed.develop.my.salesforce.com/services/data/v42.0/query/?q=SELECT+name+from+account+limit+1';

        Httprequest request = new HttpRequest();

        Http http = new Http();

        HttpResponse response;

        

        request.setEndpoint(endpoint);

        request.setMethod('GET');

        // we can use either of the two below lines for content Type.

        // request.setHeader('Content-Type','application/json');

        request.setHeader('Content-Type','application/x-www-form-urlencoded');

        request.setHeader('Authorization','Bearer ' + accessToken);

        

        response = http.send(request);

        // => {"totalSize":1,"done":true,"records":[{"attributes":{"type":"Account","url":"/services/data/v20.0/sobjects/Account/0014000000xVKZgAAO"},"Name":"Jane Doe"}]}

        System.debug('body: ' + response.getBody());

        

        

    }

    

    

    

    

}