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Create a signed URL allowing access to a resource that would usually require authentication.
Namespace: Amazon.S3
Assembly: AWSSDK.S3.dll
Version: 3.x.y.z
public virtual String GetPreSignedURL( GetPreSignedUrlRequest request )
The GetPreSignedUrlRequest that defines the parameters of the operation.
Exception | Condition |
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System.ArgumentException | |
System.ArgumentNullException |
When using query string authentication you create a query, specify an expiration time for the query, sign it with your signature, place the data in an HTTP request, and distribute the request to a user or embed the request in a web page.
A PreSigned URL can be generated for GET, PUT, DELETE and HEAD operations on your bucketName, keys, and versions.
The following examples show how to create various different pre-signed URLs.
The code sample shows a GetContents function. This will be referred to in subsequent samples to test out the generated URL.
public static string GetContents(string path) { HttpWebRequest request = HttpWebRequest.Create(path) as HttpWebRequest; HttpWebResponse response = request.GetResponse() as HttpWebResponse; using (Stream stream = response.GetResponseStream()) using (StreamReader reader = new StreamReader(stream)) { return reader.ReadToEnd(); } }
The first example creates a URL that will allow a third party to retrieve an object from S3 for a period of 5 minutes.
// Create a client AmazonS3Client client = new AmazonS3Client(); // Create a CopyObject request GetPreSignedUrlRequest request = new GetPreSignedUrlRequest { BucketName = "SampleBucket", Key = "Item1", Expires = DateTime.UtcNow.AddMinutes(5) }; // Get path for request string path = client.GetPreSignedURL(request); // Test by getting contents string contents = GetContents(path);
The following example creates a URL that will allow a third party to retrieve an object from S3 for a period of 5 minutes, and it also sets the headers to specific content, caching and encoding values.
// Create a client AmazonS3Client client = new AmazonS3Client(); // Create a CopyObject request GetPreSignedUrlRequest request = new GetPreSignedUrlRequest { BucketName = "SampleBucket", Key = "Item1", Expires = DateTime.UtcNow.AddMinutes(5) }; request.ResponseHeaderOverrides.ContentType = "text/xml+zip"; request.ResponseHeaderOverrides.ContentDisposition = "attachment; filename=dispName.pdf"; request.ResponseHeaderOverrides.CacheControl = "No-cache"; request.ResponseHeaderOverrides.ContentLanguage = "mi, en"; request.ResponseHeaderOverrides.Expires = "Thu, 01 Dec 1994 16:00:00 GMT"; request.ResponseHeaderOverrides.ContentEncoding = "x-gzip"; // Get path for request string path = client.GetPreSignedURL(request); // Test by getting contents string contents = GetContents(path);
This example creates a URL that will allow a third party to list
all objects in a specific bucket. This URL will also expire in 5 minutes.
The URL response will be the XML response for a ListBucket request.
// Create a client AmazonS3Client client = new AmazonS3Client(); // Create a CopyObject request GetPreSignedUrlRequest request = new GetPreSignedUrlRequest { BucketName = "SampleBucket", Expires = DateTime.UtcNow.AddMinutes(5) }; // Get path for request string path = client.GetPreSignedURL(request); // Retrieve objects string allObjects = GetContents(path);
This example creates a URL that will allow a third party to list
all of the owner's buckets. This URL will also expire in 5 minutes.
The URL response will be the XML response for a ListBuckets request.
// Create a client AmazonS3Client client = new AmazonS3Client(); // Create a CopyObject request GetPreSignedUrlRequest request = new GetPreSignedUrlRequest { Expires = DateTime.UtcNow.AddMinutes(5) }; // Get path for request string path = client.GetPreSignedURL(request); // Retrieve buckets string allBuckets = GetContents(path);
This final example creates a URL that allows a third party to put an object, then uses it to upload sample content. The URL is set to expire in 10 days.
// Create a client AmazonS3Client client = new AmazonS3Client(); // Create a CopyObject request GetPreSignedUrlRequest request = new GetPreSignedUrlRequest { BucketName = "SampleBucket", Key = "Item1", Verb = HttpVerb.PUT, Expires = DateTime.UtcNow.AddDays(10) }; // Get path for request string path = client.GetPreSignedURL(request); // Prepare data byte[] data = UTF8Encoding.UTF8.GetBytes("Sample text."); // Configure request HttpWebRequest httpRequest = WebRequest.Create(path) as HttpWebRequest; httpRequest.Method = "PUT"; httpRequest.ContentLength = data.Length; // Write data to stream Stream requestStream = httpRequest.GetRequestStream(); requestStream.Write(data, 0, data.Length); requestStream.Close(); // Issue request HttpWebResponse response = httpRequest.GetResponse() as HttpWebResponse;
.NET:
Supported in: 8.0 and newer, Core 3.1
.NET Standard:
Supported in: 2.0
.NET Framework:
Supported in: 4.5 and newer, 3.5