Flow

<apex:page contentType="text/plain">{!$Api.Session_ID}</apex:page>

/*
* Helper class to invoke Dynamo Batch API from Salesforce Flow.
*/

global class DynamoBatchAPIHelper {
  
  @InvocableMethod(label='Dynamo Batch API' description='Dynamo Batch API for Flow')
  public static List<DynamoAPIResult> callDynamoInvocable(List<DynamoAPIRequest> requestList) 
  {
     DynamoAPIRequest request = requestList[0];
     
     List<String> sObjectIds = new List<String>();
     
     for (SObject r : request.records) {
      String id = (String) r.get('Id');
      sObjectIds.add(id);
     }
     
     // Requires VF page named "DynamoGetSessionID" with following code:
     // <apex:page contentType="text/plain">{!$Api.Session_ID}</apex:page> 
     
     // Call VF page to get session ID for API use
     String sessionID = Page.DynamoGetSessionID.getContent().toString();
     
     // Optional way of getting session ID, works only for URL triggered flows. 
     // UserInfo.getSessionId()
     
     String bodyJson = buildBody(sessionID, request.templateID, sObjectIds);
     
     String endPoint = request.endPoint;
     
     if (String.isBlank(endPoint))
      endPoint = 'https://dynamo-api.documill.com/v1/batch';
     
     sendRequestAsync(bodyJson,UserInfo.getOrganizationId(),request.apiKey,endPoint);
        
     List<DynamoAPIResult> results = new List<DynamoAPIResult>();   
     DynamoAPIResult result = new DynamoAPIResult();
     result.status = 'Asynchronous Dynamo API call : ' + bodyJson ;
      
     return results;
  }
  

  @future(callout=true)
  public static void sendRequestAsync(String bodyJson,String orgId,String apiKey,String endPoint) 
  {
    HttpRequest req = new HttpRequest();
          
    req.setEndpoint(endPoint);
    req.setMethod('POST');
    req.setTimeout(120000);
     
    req.setHeader('x-dynamo-tenant-id', orgId);
    req.setHeader('x-dynamo-api-key', apiKey); 
    req.setHeader('Content-Type', 'application/json');  
     
    req.setBody(bodyJson);   
    Http http = new Http();
    HTTPResponse res = http.send(req);
  }
  
  private static String buildBody(String sessionID, String templateID, List<String> sObjectIds) 
  {
    String partnerServerURL = URL.getOrgDomainUrl().toExternalForm() + '/services/Soap/u/50.0/' + UserInfo.getOrganizationId();
  
    List<String> l = new List<String>();
    
    l.add('{');
    
    l.add('"template" : "' + templateID + '",');
    l.add('"tasks" : [');
    
    Integer i = 0; 
    for (String sid : sObjectIds) {
      l.add('{');
      l.add('"params" : {');
      l.add('"id" : "' + sid + '"');
      l.add('}');
      l.add('}');
      if(++i < sObjectIds.size()){
        l.add(',');
      }
    }
    
    l.add('],');
    
    l.add('"integration" : {');
    l.add('"type" : "Salesforce",');
    l.add('"sessionID" : "' + sessionID + '",');
    l.add('"serverURL" : "' + partnerServerURL + '"');
    l.add('}');
    
    l.add('}');
    
    String body = String.join(l,'');
    
    return body;
  }
  
  global class DynamoAPIRequest {
  
    @InvocableVariable(required=true)
    global String templateID;

    @InvocableVariable(required=true)
    global SObject[] records;
    
    @InvocableVariable(required=true)
    global String apiKey;
     
    @InvocableVariable(required=false)
    global String endPoint;     
  }
  
  global class DynamoAPIResult {
  
    @InvocableVariable
    global String status;

  }

}