fix: refactor and fix inbound email handling (#388)

* fix: refactor and fix inbound email handling

Author: eshanholtz

helpers/inbound/README.md

@@ -2,116 +2,50 @@
 
 ## Table of Contents
 
-* [Quick Start for Local Testing with Sample Data](#quick_start_local_sample)
-* [Quick Start for Local Testing with Real Data](#quick_start_local_real)
-* [Deploy to Heroku](#heroku)
-* [Code Walkthrough](#code_walkthrough)
+* [Example Usage](#example-usage)
 * [Testing the Source Code](#testing)
 * [Contributing](#contributing)
 
-<a name="quick_start_local_sample"></a>
-# Quick Start for Local Testing with Sample Data
-
-```bash
-git clone https://github.com/sendgrid/sendgrid-go.git
-cd sendgrid-go
-```
-
-Run the Inbound Parse listener in your terminal:
-
-```bash
-cd helpers/inbound/
-go run inbound.go
-```
-
-In another terminal, run the test data sender:
-
-```bash
-cd [path to sendgrid-go/helpers/inbound]
-go run inbound.go ./sample_data/default_data.txt http://127.0.0.1:8000/inbound
-```
-
-More sample data can be found [here](https://github.com/sendgrid/sendgrid-go/tree/master/helpers/inbound/sample_data).
-
-View the results in the first terminal.
-
-<a name="quick_start_local_real"></a>
-# Quick Start for Local Testing with Real Data
-
-[Setup your MX records.](https://sendgrid.com/docs/Classroom/Basics/Inbound_Parse_Webhook/setting_up_the_inbound_parse_webhook.html#-Setup) Depending on your domain name host, you may need to wait up to 48 hours for the settings to propagate.
-
-Run the Inbound Parse listener in your terminal:
-
-```bash
-git clone https://github.com/sendgrid/sendgrid-go.git
-go run inbound.go
-```
-
-In another terminal, use [ngrok](https://ngrok.com/) to allow external access to your machine:
-```bash
-ngrok http 8000
+# Example Usage
+
+```go
+package main
+
+import (
+    "fmt"
+    "log"
+    "net/http"
+
+    "github.com/sendgrid/sendgrid-go/helpers/inbound"
+)
+
+func inboundHandler(response http.ResponseWriter, request *http.Request) {
+	parsedEmail := Parse(request)
+    
+	fmt.Print(parsedEmail.Headers["From"])
+	
+    for filename, contents := range parsedEmail.Attachments {
+        // Do something with an attachment
+        handleAttachment(filename, contents)
+    }
+    
+    for section, body := range parsedEmail.Body {
+        // Do something with the email body
+        handleEmail(body)
+    }
+    
+    // Twilio SendGrid needs a 200 OK response to stop POSTing
+    response.WriteHeader(http.StatusOK)
+}
+
+func main() {
+	http.HandleFunc("/inbound", inboundHandler)
+	if err := http.ListenAndServe(":8000", nil); err != nil {
+		log.Fatalln("Error")
+	}
+}
 ```
 
-Update your Twilio SendGrid Incoming Parse settings: [Settings Page](https://app.sendgrid.com/settings/parse) | [Docs](https://sendgrid.com/docs/Classroom/Basics/Inbound_Parse_Webhook/setting_up_the_inbound_parse_webhook.html#-Pointing-to-a-Hostname-and-URL)
-
-- For the HOSTNAME field, use the domain that you changed the MX records (e.g. inbound.yourdomain.com)
-- For the URL field, use the URL generated by ngrok + /inbound, e.g http://XXXXXXX.ngrok.io/inbound
-
-Next, send an email to [anything]@inbound.yourdomain.com, then look at the terminal where you started the Inbound Parse listener.
-
-<a name="heroku"></a>
-# Deploy to Heroku
-
-Get a [Heroku](https://www.heroku.com) account.
-
-[![Deploy](https://www.herokucdn.com/deploy/button.svg)](https://heroku.com/deploy?template=https://github.com/sendgrid/sendgrid-go/tree/heroku-deployment)
-
-[Setup your MX records.](https://sendgrid.com/docs/Classroom/Basics/Inbound_Parse_Webhook/setting_up_the_inbound_parse_webhook.html#-Setup) Depending on your domain name host, you may need to wait up to 48 hours for the settings to propagate.
-
-Update your Twilio SendGrid Incoming Parse settings: [Settings Page](https://app.sendgrid.com/settings/parse) | [Docs](https://sendgrid.com/docs/Classroom/Basics/Inbound_Parse_Webhook/setting_up_the_inbound_parse_webhook.html#-Pointing-to-a-Hostname-and-URL)
-
-- For the HOSTNAME field, use the domain that you changed the MX records (e.g. inbound.yourdomain.com)
-- For the URL field, use the URL generated by Heroku + /inbound, e.g https://[name-of-your-app].herokuapp.com/inbound
-
-Next, send an email to [anything]@inbound.yourdomain.com, then look at your Heroku logs: https://dashboard.heroku.com/apps/[name-of-your-app]/logs
-
-While you are waiting for your MX records to propagate, you can test by using the test data sender:
-
-```bash
-git clone https://github.com/sendgrid/sendgrid-go.git
-cd sendgrid-go
-go build
-./sendgrid-go ./helpers/inbound/sample_data/default_data.txt https://[name-of-your-app].herokuapp.com/inbound
-```
-
-To make changes: clone, modify and push the changes. [Heroku CLI](https://devcenter.heroku.com/articles/heroku-command-line) is required.
-
-For example:
-```bash
-git clone [repo url]
-git checkout heroku-deployment
-heroku git:remote -a [name-of-your-app]
----make changes---
-git add -A
-git commit -m "updated configuration"
-git push heroku heroku-deployment:master
-```
-
-<a name="code_walkthrough"></a>
-# Code Walkthrough
-
-## inbound.go
-
-This module runs a net/http server, that by default (you can change those settings [here](https://github.com/sendgrid/sendgrid-go/blob/master/helpers/inbound/conf.json), listens for POSTs on http://localhost:8000. When the server receives the POST, it parses and prints the key/value data.
-
-## conf.json
-
-This file contains application environment variables (located in [conf.json](https://github.com/sendgrid/sendgrid-go/blob/master/helpers/inbound/conf.json)).
-
-## inbound.go & /sample_data
-
-This module, in conjunction with the sample data, is also used to send sample test data. It is useful for testing and development, particularly while you wait for your MX records to propagate.
-
 <a name="testing"></a>
 # Testing the Source Code