Third party service integration - ruby-on-rails

Question

I'm working on a reply from email feature in my app, and I'm using mandrillapp.com. How it works now :
1. User replies from their email to something#something.com
2. Mandril receives the mail and sends the POST request to preconfigured endpoint of my service
3. I process that post request (create internal app message)
With regards to step 3, I have basically code that should create internal app message wrapped in the begin/rescue. So any potential errors would get reported to me, which they have in the past.
However now I've encountered a user who claims that the email has been sent (step 1), I contacted the mandrill support they say they have processed it and send to my endpoint (step 2).
So that only leaves me to see what happened in the step 3, within that specific time range. My app is on heroku, and my logs stored on AWS I could go back in past to that specific time and I could see a successful POST request from mandrill side.
What can I do to catch this case moving forward? And fix it of course, because I have no idea what is going on now.
I was thinking create a model named Mandrill hooks, which would have params column which would be a serialized hash and it would save all the params which came to my endpoint from mandrill.
Then I could check counts of webhooks received by my account and the ones sent by mandrill, and hopefully I spot 1 with different count, and since I will have the params data in my db, I'd be able to reproduce the case.
Or is there more wise approach, as this looks naive even to me?

Answer 1

I think there may be a wiser approach that enables you to have more control over everything and this sounds extremely similar to what I recently accomplished and I answered a similar question here. Does this help at all or is there some more specific help that you would like?
** Edit: Linked post/code below
I am running my Mandrill Webhook handling as an API project in VS and this is how I am have gotten it up and running:
[HttpPost]
public string Post()
{
/* Every Mandrill webhook uses the same general data format, regardless of the event type.
* The webhook request is a standard POST request with a single parameter (currently) - 'mandrill_events'. */
string validJson = HttpContext.Current.Request.Form["mandrill_events"].Replace("mandrill_events=", ""); //"mandrill_events=" is not valid JSON. If you take that out you should be able to parse it. //http://stackoverflow.com/questions/24521326/deserializing-mandrillapp-webhook-response
List<MandrillEvent> mandrillEventList = JsonConvert.DeserializeObject<List<MandrillEvent>>(validJson);
foreach (MandrillEvent mandrillEvent in mandrillEventList)
{
if (mandrillEvent.msg.email != null)
{
DataLayer.ReportingData.EmailSave(mandrillEvent); //Saves MandrillEvent email to database and sets a messageId for datalayer
}
}
foreach (MandrillEvent mandrillEvent in mandrillEventList)
{
DataLayer.ReportingData.MandrillEventSave(mandrillEvent); //Saves MandrillEvent object to database
}
return "DONE";
}
I then took the documented (and undocumented) JSON parameters of "mandrill_event" and used json2csharp.com to generate the C# properties. I created a class called "MandrillEvent.cs" and put these within:
public class SmtpEvent
{
public int ts { get; set; }
public DateTime SmtpTs { get; set; }
public string type { get; set; }
public string diag { get; set; }
public string source_ip { get; set; }
public string destination_ip { get; set; }
public int size { get; set; }
public int smtpId { get; set; } //added for datalayer
}
public class Msg
{
public int ts { get; set; }
public DateTime MsgTs { get; set; }
public string _id { get; set; }
public string state { get; set; }
public string subject { get; set; }
public string email { get; set; }
public List<object> tags { get; set; }
public List<object> opens { get; set; } //an array of containing an item for each time the message was opened. Each open includes the following keys: "ts", "ip", "location", "ua"
public List<object> clicks { get; set; } //an array containing an item for each click recorded for the message. Each item contains the following: "ts", "url"
public List<SmtpEvent> smtp_events { get; set; }
public List<object> resends { get; set; } //not currently documented on http://help.mandrill.com/entries/58303976-Message-Event-Webhook-format
public string _version { get; set; }
public string diag { get; set; } //for bounced and soft-bounced messages, provides the specific SMTP response code and bounce description, if any, received from the remote server
public int bgtools_code { get; set; } //Is it this? for bounced and soft-bounced messages, a short description of the bounce reason such as bad_mailbox or invalid_domain. (not currently documented but in JSON response)
public string sender { get; set; }
public object template { get; set; }
public string bounce_description { get; set; }
public Msg()
{
tags = new List<object>();
opens = new List<object>();
clicks = new List<object>();
smtp_events = new List<SmtpEvent>();
smtp_events.Add(new SmtpEvent());
resends = new List<object>();
}
}
public class MandrillEvent
{
public string #event { get; set; }
public string _id { get; set; }
public Msg msg { get; set; }
public int ts { get; set; }
public DateTime MandrillEventTs { get; set; }
public int messageId { get; set; } //added for datalayer
public List<string> SingleMandrillEventData { get; set; } //added for Reporting
public MandrillEvent()
{
SingleMandrillEventData = new List<string>();
msg = new Msg();
}
}
You now have your "mandrill_events" JSON object as a functioning C# object!! Did this help or do you need some more clarification/help?