Amazon CloudFront invalidation in ASP.Net - asp.net

Question

I am not sure how to send a request using ASP.Net to Amazon CloudFront to invalidate an object.
The details are here http://docs.amazonwebservices.com/AmazonCloudFront/latest/DeveloperGuide/index.html?Invalidation.html
but I am not sure how to implement this in ASP.Net.

Answer 1

The accepted answer no longer works as of the latest version of the AWS SDK for .NET (1.5.8.0). This should do the trick:
using Amazon;
using Amazon.CloudFront.Model;
...
var client = AWSClientFactory.CreateAmazonCloudFrontClient(accessKey, secretKey);
client.CreateInvalidation(new CreateInvalidationRequest {
DistributionId = distributionID,
InvalidationBatch = new InvalidationBatch {
Paths = new Paths {
Quantity = arrayofpaths.Length,
Items = arrayofpaths.ToList()
},
CallerReference = DateTime.Now.Ticks.ToString()
}
});

Answer 2

Got it working, here it is if anyone else finds it useful.
public static void InvalidateContent(string distributionId, string fileName)
{
string httpDate = Helpers.GetHttpDate();
ASCIIEncoding encoding = new ASCIIEncoding();
string postData = #"<InvalidationBatch>" +
" <Path>/" + fileName + "</Path>" +
" <CallerReference>" + httpDate + "</CallerReference>" +
"</InvalidationBatch>";
byte[] data = encoding.GetBytes(postData);
// Prepare web request...
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create("https://cloudfront.amazonaws.com/2010-08-01/distribution/" + distributionId + "/invalidation");
webRequest.Method = "POST";
webRequest.ContentType = "text/xml";
webRequest.Headers.Add("x-amz-date", httpDate);
Encoding ae = new UTF8Encoding();
HMACSHA1 signature = new HMACSHA1(ae.GetBytes(GlobalSettings.AWSSecretAccessKey.ToCharArray()));
string b64 = Convert.ToBase64String(signature.ComputeHash(ae.GetBytes(webRequest.Headers["x-amz-date"].ToCharArray())));
webRequest.Headers.Add(HttpRequestHeader.Authorization, "AWS" + " " + GlobalSettings.AWSAccessKeyId + ":" + b64);
webRequest.ContentLength = data.Length;
Stream newStream = webRequest.GetRequestStream();
// Send the data.
newStream.Write(data, 0, data.Length);
newStream.Close();
}
/// <summary>
/// Gets a proper HTTP date
/// </summary>
public static string GetHttpDate()
{
// Setting the Culture will ensure we get a proper HTTP Date.
string date = System.DateTime.UtcNow.ToString("ddd, dd MMM yyyy HH:mm:ss ", System.Globalization.CultureInfo.InvariantCulture) + "GMT";
return date;
}

Answer 3

Here's a python version of the above, if anyone finds it useful
from datetime import datetime
import urllib2, base64, hmac, hashlib
def getHTTPDate():
return datetime.utcnow().strftime("%a, %d %b %Y %H:%M:%S UTC")
def submitInvalidationRequest(fileName,distributionId):
url = "https://cloudfront.amazonaws.com/2010-08-01/distribution/" + distributionId + "/invalidation"
httpDate = getHTTPDate();
postData = "<InvalidationBatch>" +"<Path>/" + fileName + "</Path>" +"<CallerReference>" + httpDate + "</CallerReference>" +"</InvalidationBatch>";
sig = hmac.new(AWSSecretAccessKey, unicode(httpDate), hashlib.sha1)
headers = {"ContentType": "text/xml",
"x-amz-date": httpDate,
"Authorization":"AWS " + AWSAccessKeyId + ":" + base64.b64encode( sig.digest() )}
req = urllib2.Request(url,postData,headers)
return urllib2.urlopen(req).read()

Answer 4

using the AWSSDK .net api wrapper from amazon makes this task even easier.
using Amazon.CloudFront.Model;
...
var client = Amazon.AWSClientFactory.CreateAmazonCloudFrontClient(ConfigurationManager.AppSettings["Aws.AccessKey"],
ConfigurationManager.AppSettings["Aws.SecretKey"]);
var request = new PostInvalidationRequest();
request.DistributionId = ConfigurationManager.AppSettings["Cdn.DistributionId"];
request.InvalidationBatch = new InvalidationBatch();
request.InvalidationBatch.CallerReference = new Guid().ToString();
request.InvalidationBatch.Paths = PathsInput.Text.Split(new[]{'\n','\r'},StringSplitOptions.RemoveEmptyEntries).ToList();
var response = client.PostInvalidation(request);

Answer 5

Here's perl:
use warnings;
use strict;
use HTTP::Date;
use Digest::SHA qw(hmac_sha1);
use LWP::UserAgent;
use MIME::Base64;
use Encode qw(encode_utf8);
#ARGV == 4 || die "usage: $0 url distribution_id accesskey secretkey\n";
my $invalid_url = $ARGV[0];
my $distribution_id = $ARGV[1];
my $accesskey = $ARGV[2];
my $secretkey = $ARGV[3];
my $url = "https://cloudfront.amazonaws.com/2010-11-01/distribution/$distribution_id/invalidation";
my $date = time2str;
my $post_data = <<HERE;
<?xml version="1.0" encoding="UTF-8"?>
<InvalidationBatch>
<Path>$invalid_url</Path>
<CallerReference>$date</CallerReference>
</InvalidationBatch>
HERE
my $sig = encode_base64(hmac_sha1(encode_utf8($date),encode_utf8($secretkey)));
my $browser = LWP::UserAgent->new;
my $res = $browser->post($url,
"Content" => $post_data,
"ContentType" => "text/xml",
"x-amz-date" => $date,
"Authorization" => "AWS $accesskey:$sig");
print $res->status_line, "\n", $res->content;