BlobSasPolicy.cs

using System;
using System.Collections.Generic;
using System.Text;
using Azure.Storage;
using Azure.Storage.Sas;

namespace FluentStorage.Azure.Blobs {
	/// <summary>
	/// Defines a SAS policy for a blob
	/// </summary>
	public class BlobSasPolicy : OffsetSasPolicy {
		/// <summary>
		/// 
		/// </summary>
		/// <param name="startTime"></param>
		/// <param name="duration"></param>
		public BlobSasPolicy(DateTimeOffset startTime, TimeSpan duration) : base(startTime, duration) {
		}

		/// <summary>
		/// Permissions for this sas policy
		/// </summary>
		public BlobSasPermission Permissions { get; set; } = BlobSasPermission.Read;

		internal string ToSasQuery(StorageSharedKeyCredential sasSigningCredentials, string containerName, string blobName) {
			if (sasSigningCredentials is null)
				throw new ArgumentNullException(nameof(sasSigningCredentials));

			var sas = new BlobSasBuilder {
				BlobContainerName = containerName,
				BlobName = blobName,
				Protocol = SasProtocol.Https,
				StartsOn = StartTime,
				ExpiresOn = ExpiryTime
			};

			sas.SetPermissions((BlobSasPermissions)(int)Permissions);

			string query = sas.ToSasQueryParameters(sasSigningCredentials).ToString();
			return query;
		}
	}
}