flameoftheforest · July 21, 2023 09:35 · runtimesoftware · Jul 21, 2023
diff --git a/TestClass.cs b/TestClass.cs
 using Amazon;
 using Amazon.S3;
 using Amazon.S3.Model;
 using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Net;
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Text;

 namespace TEST00
 {
    public class TestClass
    {
        private IAmazonS3 S3;
        const string DOMAIN = "theBigRobot.org";
        const string API_KEY = "key-bigrobotkey";

        public void Test00()
        {
            PostToMailGun("[email protected]", "The Big Robot", "[email protected]", "Greeting from Big Robot", "hello, Big Robot greets you.", "<html>hello, <b>Big Robot</b> greets you.</html>");
        }

        /// <summary>
        /// This sample code demonstrates a few things:
        /// - Using HttpClient to POST a multipart form.
        /// - POST the said form to MailGun.
        /// - Attaching files to the MailGun submission.
        /// - Using Amazon S3 Client.
        ///
        /// Implementation References (with thanks):         
        /// https://github.com/restsharp/RestSharp/wiki/Recommended-Usage
        /// https://stackoverflow.com/questions/16906711/httpclient-how-to-upload-multiple-files-at-once
        /// https://github.com/Vodurden/Http-Multipart-Data-Parser
        ///
        /// </summary>
        /// <param name="recipientEmail"></param>
        /// <param name="senderName"></param>
        /// <param name="senderEmail"></param>
        /// <param name="subject"></param>
        /// <param name="textBody"></param>
        /// <param name="htmlBody"></param>
        private void PostToMailGun(string recipientEmail, string senderName, string senderEmail, string subject, string textBody, string htmlBody)
        {
            HttpClient client = new HttpClient();
            var encoded = Convert.ToBase64String(Encoding.ASCII.GetBytes($"api:{API_KEY}"));
            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", encoded);
            var content = new MultipartFormDataContent();
            content.Add(new StringContent(DOMAIN), "domain"); // may need url-encode
            content.Add(new StringContent($"{senderName} <{senderEmail}>"), "from");
            content.Add(new StringContent($"{recipientEmail}"), "to");
            content.Add(new StringContent($"{subject}"), "subject");
            content.Add(new StringContent($"{htmlBody}"), "html");
            content.Add(new StringContent($"{textBody}"), "text");

            // The arrangement of how attachments should be managed is heavily subjected to discussion.
            // This only serves as a starting point and totally lacks flexibility.
            S3Returns file1 = GetStreamFromS3("BUCKET", "Jesus.jpg");
            content.Add(CreateAttachmentContent(file1.Stream, "Jesus.jpg", file1.ContentType));

            S3Returns file2 = GetStreamFromS3("BUCKET", "why seek ye the living among the dead.jpg");
            content.Add(CreateAttachmentContent(file2.Stream, "why_seek_ye.jpg", file2.ContentType));

            HttpResponseMessage response = client.PostAsync($"https://api.mailgun.net/v3/{DOMAIN}/messages", content).Result;

            if (!response.IsSuccessStatusCode)
            {
                throw new Exception($"{response.ReasonPhrase}");
            }
        }

        private StreamContent CreateAttachmentContent(Stream stream, string fileName, string contentType)
        {
            var fileContent = new StreamContent(stream);
            fileContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
            {
                Name = "\"attachment[]\"",
                FileName = "\"" + fileName + "\""
            }; // the extra quotes are key here
            fileContent.Headers.ContentType = new MediaTypeHeaderValue(contentType);
            return fileContent;
        }

        private S3Returns GetStreamFromS3(string bucket, string key)
        {
            GetObjectRequest req = new GetObjectRequest
            {
                BucketName = bucket,
                Key = key
            };

            GetObjectResponse resp = S3.GetObjectAsync(req).Result;
            if (resp.HttpStatusCode != HttpStatusCode.OK)
            {
                throw new Exception("something's wrong");
            }

            return new S3Returns
            {
                Stream = resp.ResponseStream,
                ContentType = resp.Headers.ContentType
            };
        }

        public TestClass()
        {
            S3 = new AmazonS3Client("KEY", "SECRET", RegionEndpoint.SIBERIA);
        }
    }

    internal class S3Returns
    {
        public Stream Stream { get; set; }
        public string ContentType { get; set; }
    }
 }
	using Amazon;
	using Amazon.S3;
	using Amazon.S3.Model;
	using System;
	using System.Collections.Generic;
	using System.IO;
	using System.Net;
	using System.Net.Http;
	using System.Net.Http.Headers;
	using System.Text;

	namespace TEST00
	{
	public class TestClass
	{
	private IAmazonS3 S3;
	const string DOMAIN = "theBigRobot.org";
	const string API_KEY = "key-bigrobotkey";

	public void Test00()
	{
	PostToMailGun("[email protected]", "The Big Robot", "[email protected]", "Greeting from Big Robot", "hello, Big Robot greets you.", "<html>hello, <b>Big Robot</b> greets you.</html>");
	}

	/// <summary>
	/// This sample code demonstrates a few things:
	/// - Using HttpClient to POST a multipart form.
	/// - POST the said form to MailGun.
	/// - Attaching files to the MailGun submission.
	/// - Using Amazon S3 Client.
	///
	/// Implementation References (with thanks):
	/// https://github.com/restsharp/RestSharp/wiki/Recommended-Usage
	/// https://stackoverflow.com/questions/16906711/httpclient-how-to-upload-multiple-files-at-once
	/// https://github.com/Vodurden/Http-Multipart-Data-Parser
	///
	/// </summary>
	/// <param name="recipientEmail"></param>
	/// <param name="senderName"></param>
	/// <param name="senderEmail"></param>
	/// <param name="subject"></param>
	/// <param name="textBody"></param>
	/// <param name="htmlBody"></param>
	private void PostToMailGun(string recipientEmail, string senderName, string senderEmail, string subject, string textBody, string htmlBody)
	{
	HttpClient client = new HttpClient();
	var encoded = Convert.ToBase64String(Encoding.ASCII.GetBytes($"api:{API_KEY}"));
	client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", encoded);
	var content = new MultipartFormDataContent();
	content.Add(new StringContent(DOMAIN), "domain"); // may need url-encode
	content.Add(new StringContent($"{senderName} <{senderEmail}>"), "from");
	content.Add(new StringContent($"{recipientEmail}"), "to");
	content.Add(new StringContent($"{subject}"), "subject");
	content.Add(new StringContent($"{htmlBody}"), "html");
	content.Add(new StringContent($"{textBody}"), "text");

	// The arrangement of how attachments should be managed is heavily subjected to discussion.
	// This only serves as a starting point and totally lacks flexibility.
	S3Returns file1 = GetStreamFromS3("BUCKET", "Jesus.jpg");
	content.Add(CreateAttachmentContent(file1.Stream, "Jesus.jpg", file1.ContentType));

	S3Returns file2 = GetStreamFromS3("BUCKET", "why seek ye the living among the dead.jpg");
	content.Add(CreateAttachmentContent(file2.Stream, "why_seek_ye.jpg", file2.ContentType));

	HttpResponseMessage response = client.PostAsync($"https://api.mailgun.net/v3/{DOMAIN}/messages", content).Result;

	if (!response.IsSuccessStatusCode)
	{
	throw new Exception($"{response.ReasonPhrase}");
	}
	}

	private StreamContent CreateAttachmentContent(Stream stream, string fileName, string contentType)
	{
	var fileContent = new StreamContent(stream);
	fileContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
	{
	Name = "\"attachment[]\"",
	FileName = "\"" + fileName + "\""
	}; // the extra quotes are key here
	fileContent.Headers.ContentType = new MediaTypeHeaderValue(contentType);
	return fileContent;
	}

	private S3Returns GetStreamFromS3(string bucket, string key)
	{
	GetObjectRequest req = new GetObjectRequest
	{
	BucketName = bucket,
	Key = key
	};

	GetObjectResponse resp = S3.GetObjectAsync(req).Result;
	if (resp.HttpStatusCode != HttpStatusCode.OK)
	{
	throw new Exception("something's wrong");
	}

	return new S3Returns
	{
	Stream = resp.ResponseStream,
	ContentType = resp.Headers.ContentType
	};
	}

	public TestClass()
	{
	S3 = new AmazonS3Client("KEY", "SECRET", RegionEndpoint.SIBERIA);
	}
	}

	internal class S3Returns
	{
	public Stream Stream { get; set; }
	public string ContentType { get; set; }
	}
	}