FATAL_ERROR|System.LimitException: Too many Email Invocations: 11

Question

I am writing a batch class to send the emails based on certian criteria. I see that the parameters are passed right, no errors, but I end up receiving multiple duplicate emails when I run it. Here is the code

Two issues that I am trying to resolve

1. When there are less than 10 emails to be sent out, the code works fine, but sends duplicate emails

2. When there are more than more than 10 emails in the list that I am sending to, I get an error saying:

   FATAL_ERROR|System.LimitException: Too many Email Invocations: 11

Batch:

global void execute(Database.BatchableContext BC, List<OrderApi__Badge__c> scope){
    for(Order_c fbdge : [select Id,Description__c,Type__c,Contact__c,Contact__r.Date__c,Contact__r.FirstName,Contact__r.Email,Active__c,Type__r.Name From Order__c where (Type__r.Name ='A' or Type__r.Name ='B') and OrderApi__Is_Active__c =true and (Contact__r.Cat__c <> ' Life')]){
        bge.add(fbdge);
        contact.put(fbdge.Contact__c, fbdge.Contact__r.Email);
    }
    
    if(contact.size()>0){
        
        List<Messaging.SingleEmailMessage> mails = newList<Messaging.SingleEmailMessage>();
        List<String> email = new List<String>();
        List<String> ccemail = new List<String>();
        Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();  
        
        for(Id ids : contact.keyset()){
            
            email.clear();
            for(Order__c bdg :[select id,Contact__r.Email from Order__c where Contact__r.Email=:contact.get(ids) LIMIT 1]){
                
                email.add(bdg.Contact__r.Email);
            }
            Contact c = [select id, Email from Contact where email <> null limit 1];
            
            EmailTemplate templateId = [Select id from EmailTemplate where name = 'Test'];
            mail.setToAddresses(email);
            mail.setccAddresses(ccemail);
            mail.setTargetObjectId(c.Id);                                           mail.setTreatTargetObjectAsRecipient(false);
            mail.setTemplateID(templateId.Id);
            mail.setSaveAsActivity(false);
            mails.add(mail);
            
            if(mails.size())>0{                       
                
                Messaging.sendEmail(mails);
            }       
            
        }        
    }
}
global void finish(Database.BatchableContext BC){
    
}

}

Answer 1

Never call Messaging.sendEmail (nor any other method which consumes governors) inside a loop. Here's your basic problem:

for(Id ids : contact.keyset()){
    // some logic
    Messaging.sendEmail(mails);
    // don't ever do this
}

Instead, send the emails after your loop:

for(Id ids : contact.keyset()){
    // some logic
}
Messaging.sendEmail(mails);
// now you just invoke the send method once

Making this change will also fix the duplicates issue, as you are currently building one collection containing all the emails you want to send (good), then sending the entire collection for each element therein (bad).

---

Your other problem is you're sharing the same instance throughout the loop.

Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
for(Id ids : contact.keyset()){
    mail.setToAddress(...);
    // each loop iteration overwrites the previous instance variables
}

Instead, declare your instance inside the loop.

for(Id ids : contact.keyset()){
    Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
    mail.setToAddress(...);
    // each loop iteration has its own instance
}