AzureJsonStore.cs

AzureJsonStore.cs

// --------------------------------------------------------------------------------------------------------------------
// <summary>
//   The Azure JSON table storage provider.
// </summary>
// --------------------------------------------------------------------------------------------------------------------

namespace Grains.Utilities
{
    using System.Configuration;
    using System.Threading.Tasks;

    using FreeBay.Models.Utility;

    using Microsoft.WindowsAzure;
    using Microsoft.WindowsAzure.Storage;
    using Microsoft.WindowsAzure.Storage.Table;

    using Newtonsoft.Json;

    using Orleans;
    using Orleans.Runtime;
    using Orleans.Storage;

    /// <summary>
    /// The Azure JSON table storage provider.
    /// </summary>
    public class AzureJsonStore : IStorageProvider
    {
        /// <summary>
        /// The connection string setting.
        /// </summary>
        public const string ConnectionStringSetting = "ConnectionStringSetting";

        /// <summary>
        /// The table name setting.
        /// </summary>
        public const string TableNameSetting = "TableName";

        /// <summary>
        /// Gets or sets the log.
        /// </summary>
        public OrleansLogger Log { get; set; }

        /// <summary>
        /// Gets or sets the name.
        /// </summary>
        public string Name { get; set; }

        /// <summary>
        /// Gets or sets the table.
        /// </summary>
        public CloudTable Table { get; set; }

        /// <summary>
        /// Gets or sets the account.
        /// </summary>
        public CloudStorageAccount Account { get; set; }

        /// <summary>
        /// Gets or sets the client.
        /// </summary>
        public CloudTableClient Client { get; set; }

        /// <summary>
        /// Initialization function called by Orleans Provider Manager when a new provider class instance  is created
        /// </summary>
        /// <param name="name">Name assigned for this provider</param>
        /// <param name="providerRuntime">Callback for accessing system functions in the Provider Runtime</param>
        /// <param name="config">Configuration metadata to be used for this provider instance</param>
        /// <returns>
        /// Completion promise Task for the initialization work for this provider
        /// </returns>
        public async Task Init(string name, Orleans.Providers.IProviderRuntime providerRuntime, Orleans.Providers.IProviderConfiguration config)
        {
            var connectionStringSetting = config.Properties[ConnectionStringSetting];
            if (string.IsNullOrWhiteSpace(connectionStringSetting))
            {
                throw new ConfigurationErrorsException(ConnectionStringSetting + " must be provided.");
            }

            var tableName = config.Properties[TableNameSetting];
            if (string.IsNullOrWhiteSpace(tableName))
            {
                throw new ConfigurationErrorsException(TableNameSetting + " must be provided.");
            }

            var connectionString = CloudConfigurationManager.GetSetting(connectionStringSetting);

            this.Account = CloudStorageAccount.Parse(connectionString);
            this.Client = new CloudTableClient(this.Account.TableStorageUri, this.Account.Credentials);
            this.Table = this.Client.GetTableReference(tableName);
            await this.Table.CreateIfNotExistsAsync();
        }

        /// <summary>
        /// Close function for this storage provider instance.
        /// </summary>
        /// <returns>
        /// Completion promise for the Close operation on this provider.
        /// </returns>
        public Task Close()
        {
            return Task.FromResult(0);
        }

        /// <summary>
        /// Read data function for this storage provider instance.
        /// </summary>
        /// <param name="grainType">Type of this grain [fully qualified class name]</param>
        /// <param name="grainRef">Grain reference object for this grain.</param>
        /// <param name="grainState">State data object to be populated for this grain.</param>
        /// <returns>
        /// Completion promise for the Read operation on the specified grain.
        /// </returns>
        public async Task ReadStateAsync(string grainType, GrainReference grainRef, IGrainState grainState)
        {
            var rowkey = grainState.GetType().Name;
            var partitionKey = grainRef.ToKeyString();
            var query = new TableQuery<GrainStateTableEntity>().Where(
                TableQuery.CombineFilters(
                    TableQuery.GenerateFilterCondition("PartitionKey", QueryComparisons.Equal, partitionKey),
                    TableOperators.And,
                    TableQuery.GenerateFilterCondition("RowKey", QueryComparisons.Equal, rowkey)));
            var result = await this.Table.ExecuteQuerySegmentedAsync(query, null);
            if (result.Results != null && result.Results.Count > 0)
            {
                var entity = result.Results[0];
                var properties = (IGrainState)JsonConvert.DeserializeObject(entity.State, grainState.GetType(), Globals.JsonConfig);
                grainState.SetAll(properties.AsDictionary());
            }
        }

        /// <summary>
        /// Write data function for this storage provider instance.
        /// </summary>
        /// <param name="grainType">Type of this grain [fully qualified class name]</param>
        /// <param name="grainRef">Grain reference object for this grain.</param>
        /// <param name="grainState">State data object to be written for this grain.</param>
        /// <returns>
        /// Completion promise for the Write operation on the specified grain.
        /// </returns>
        public async Task WriteStateAsync(string grainType, GrainReference grainRef, IGrainState grainState)
        {
            var rowkey = grainState.GetType().Name;
            var partitionKey = grainRef.ToKeyString();
            var entity = new GrainStateTableEntity { PartitionKey = partitionKey, RowKey = rowkey, State = JsonConvert.SerializeObject(grainState, Globals.JsonConfig) };
            await this.Table.ExecuteAsync(TableOperation.InsertOrReplace(entity));
        }

        /// <summary>
        /// Delete / Clear data function for this storage provider instance.
        /// </summary>
        /// <param name="grainType">Type of this grain [fully qualified class name]</param>
        /// <param name="grainRef">Grain reference object for this grain.</param>
        /// <param name="grainState">Copy of last-known state data object for this grain.</param>
        /// <returns>
        /// Completion promise for the Delete operation on the specified grain.
        /// </returns>
        public async Task ClearStateAsync(string grainType, GrainReference grainRef, IGrainState grainState)
        {
            var rowkey = grainState.GetType().Name;
            var partitionKey = grainRef.ToKeyString();
            var entity = new GrainStateTableEntity { PartitionKey = partitionKey, RowKey = rowkey };
            await this.Table.ExecuteAsync(TableOperation.Delete(entity));
        }

        /// <summary>
        /// The grain state table entity.
        /// </summary>
        public class GrainStateTableEntity : TableEntity
        {
            /// <summary>
            /// Gets or sets the state.
            /// </summary>
            public string State { get; set; }
        }
    }
}