apewer-dotnet/Apewer.Source/Externals/MySql.Data-6.10.9/MySqlClient/Memcached/TextClient.cs

#if MYSQL_6_10

// Copyright © 2004, 2016, Oracle and/or its affiliates. All rights reserved.
//
// MySQL Connector/NET is licensed under the terms of the GPLv2
// <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most 
// MySQL Connectors. There are special exceptions to the terms and 
// conditions of the GPLv2 as it is applied to this software, see the 
// FLOSS License Exception
// <http://www.mysql.com/about/legal/licensing/foss-exception.html>.
//
// This program is free software; you can redistribute it and/or modify 
// it under the terms of the GNU General Public License as published 
// by the Free Software Foundation; version 2 of the License.
//
// This program is distributed in the hope that it will be useful, but 
// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 
// for more details.
//
// You should have received a copy of the GNU General Public License along 
// with this program; if not, write to the Free Software Foundation, Inc., 
// 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;

namespace Externals.MySql.Data.MySqlClient.Memcached
{
    /// <summary>
    /// Implementation of the Memcached text client protocol.
    /// </summary>
    internal class TextClient : Client
    {
        private readonly Encoding _encoding;

        private static readonly string PROTOCOL_ADD = "add";
        private static readonly string PROTOCOL_APPEND = "append";
        private static readonly string PROTOCOL_CAS = "cas";
        private static readonly string PROTOCOL_DECREMENT = "decr";
        private static readonly string PROTOCOL_DELETE = "delete";
        private static readonly string PROTOCOL_FLUSHALL = "flush_all";
        private static readonly string PROTOCOL_GETS = "gets";
        private static readonly string PROTOCOL_INCREMENT = "incr";
        private static readonly string PROTOCOL_PREPEND = "prepend";
        private static readonly string PROTOCOL_REPLACE = "replace";
        private static readonly string PROTOCOL_SET = "set";

        private static readonly string VALUE = "VALUE";
        private static readonly string END = "END";
        // Errors
        private static readonly string ERR_ERROR = "ERROR";
        private static readonly string ERR_CLIENT_ERROR = "CLIENT_ERROR";
        private static readonly string ERR_SERVER_ERROR = "SERVER_ERROR";

        protected internal TextClient(string server, uint port) : base(server, port)
        {
            _encoding = Encoding.UTF8;
        }

        #region Memcached protocol interface

        public override void Add(string key, object data, TimeSpan expiration)
        {
            SendCommand(PROTOCOL_ADD, key, data, expiration);
        }

        public override void Append(string key, object data)
        {
            SendCommand(PROTOCOL_APPEND, key, data);
        }

        public override void Cas(string key, object data, TimeSpan expiration, ulong casUnique)
        {
            SendCommand(PROTOCOL_CAS, key, data, expiration, casUnique);
        }

        public override void Decrement(string key, int amount)
        {
            SendCommand(PROTOCOL_DECREMENT, key, amount);
        }

        public override void Delete(string key)
        {
            SendCommand(PROTOCOL_DELETE, key);
        }

        public override void FlushAll(TimeSpan delay)
        {
            SendCommand(PROTOCOL_FLUSHALL, delay);
        }

        public override KeyValuePair<string, object> Get(string key)
        {
            KeyValuePair<string, object>[] kvp = Gets(key);
            if (kvp.Length == 0)
                throw new MemcachedException("Item does not exists.");
            else
                return kvp[0];
        }

        private KeyValuePair<string, object>[] Gets(params string[] keys)
        {
            StringBuilder sb = new StringBuilder();
            sb.Append(string.Format("{0}", PROTOCOL_GETS));
            for (int i = 0; i < keys.Length; i++)
            {
                sb.Append(string.Format(" {0}", keys[i]));
            }
            sb.Append("\r\n");
            SendData(sb.ToString());
            byte[] res = GetResponse();
            return ParseGetResponse(res);
        }

        public override void Increment(string key, int amount)
        {
            SendCommand(PROTOCOL_INCREMENT, key, amount);
        }

        public override void Prepend(string key, object data)
        {
            SendCommand(PROTOCOL_PREPEND, key, data);
        }

        public override void Replace(string key, object data, TimeSpan expiration)
        {
            SendCommand(PROTOCOL_REPLACE, key, data, expiration);
        }

        public override void Set(string key, object data, TimeSpan expiration)
        {
            SendCommand(PROTOCOL_SET, key, data, expiration);
        }

        #endregion

        #region Support methods


        /// <summary>
        /// Sends a command to the memcached server.
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="key"></param>
        /// <param name="data"></param>
        /// <param name="expiration"></param>
        /// <param name="casUnique"></param>
        /// <remarks>This version is for commands that take a key, data, expiration and casUnique.</remarks>
        private void SendCommand(string cmd, string key, object data, TimeSpan expiration, ulong casUnique)
        {
            StringBuilder sb = new StringBuilder();
            // set key flags exptime 
            sb.Append(string.Format("{0} {1} 0 {2} ", cmd, key, (int)(expiration.TotalSeconds)));
            byte[] buf = _encoding.GetBytes(data.ToString());
            string s = _encoding.GetString(buf, 0, buf.Length);
            sb.Append(s.Length.ToString());
            sb.AppendFormat(" {0}", casUnique);
            sb.Append("\r\n");
            sb.Append(s);
            sb.Append("\r\n");
            SendData(sb.ToString());
            GetResponse();
        }

        /// <summary>
        /// Sends a command to the memcached server.
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="key"></param>
        /// <param name="data"></param>
        /// <param name="expiration"></param>
        /// <remarks>This version is for commands that take a key, data and expiration</remarks>
        private void SendCommand(string cmd, string key, object data, TimeSpan expiration)
        {
            StringBuilder sb = new StringBuilder();
            // set key flags exptime 
            sb.Append(string.Format("{0} {1} 0 {2} ", cmd, key, (int)(expiration.TotalSeconds)));
            byte[] buf = _encoding.GetBytes(data.ToString());
            string s = _encoding.GetString(buf, 0, buf.Length);
            sb.Append(s.Length.ToString());
            sb.Append("\r\n");
            sb.Append(s);
            sb.Append("\r\n");
            SendData(sb.ToString());
            GetResponse();
        }

        /// <summary>
        /// Send a command to memcached server.
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="key"></param>
        /// <param name="data"></param>    
        /// <remarks>This version is for commands that don't need flags neither expiration fields.</remarks>
        private void SendCommand(string cmd, string key, object data)
        {
            StringBuilder sb = new StringBuilder();
            // set key 
            sb.Append(string.Format("{0} {1} ", cmd, key));
            byte[] buf = _encoding.GetBytes(data.ToString());
            string s = _encoding.GetString(buf, 0, buf.Length);
            if ((cmd == PROTOCOL_APPEND) || (cmd == PROTOCOL_PREPEND))
            {
                sb.Append("0 0 ");
            }
            sb.Append(s.Length.ToString());
            sb.Append("\r\n");
            sb.Append(s);
            sb.Append("\r\n");
            SendData(sb.ToString());
            GetResponse();
        }

        /// <summary>
        /// Sends a command to the server.
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="key"></param>
        /// <remarks>This version is for commands that only require a key</remarks>
        private void SendCommand(string cmd, string key)
        {
            StringBuilder sb = new StringBuilder();
            // set key 
            sb.Append(string.Format("{0} {1} ", cmd, key));
            sb.Append("\r\n");
            SendData(sb.ToString());
            GetResponse();
        }

        /// <summary>
        /// Sends a command to the server.
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="key"></param>
        /// <param name="amount"></param>
        /// <remarks>This version is for commands that only require a key and an integer value.</remarks>
        private void SendCommand(string cmd, string key, int amount)
        {
            StringBuilder sb = new StringBuilder();
            // set key 
            sb.Append(string.Format("{0} {1} {2}", cmd, key, amount));
            sb.Append("\r\n");
            SendData(sb.ToString());
            GetResponse();
        }

        /// <summary>
        /// Sends a command to the server.
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="expiration"></param>
        /// <remarks>This version is for commands that only require a key and expiration.</remarks>
        private void SendCommand(string cmd, TimeSpan expiration)
        {
            StringBuilder sb = new StringBuilder();
            sb.Append(string.Format("{0} {1}\r\n", PROTOCOL_FLUSHALL, expiration.TotalSeconds));
            SendData(sb.ToString());
            GetResponse();
        }

        private void ValidateErrorResponse(byte[] res)
        {
            string s = _encoding.GetString(res, 0, res.Length);
            if ((s.StartsWith(ERR_ERROR, StringComparison.OrdinalIgnoreCase)) ||
                (s.StartsWith(ERR_CLIENT_ERROR, StringComparison.OrdinalIgnoreCase)) ||
                (s.StartsWith(ERR_SERVER_ERROR, StringComparison.OrdinalIgnoreCase)))
            {
                throw new MemcachedException(s);
            }
        }

        private void SendData(string sData)
        {
            byte[] data = _encoding.GetBytes(sData);
            stream.Write(data, 0, data.Length);
        }

        private KeyValuePair<string, object>[] ParseGetResponse(byte[] input)
        {
            // VALUE key2 10 9 2\r\n111222333\r\nEND\r\n
            string[] sInput = _encoding.GetString(input, 0, input.Length).Split(new string[] { "\r\n" }, StringSplitOptions.None);
            List<KeyValuePair<string, object>> l = new List<KeyValuePair<string, object>>();
            int i = 0;
            string key = "";
            KeyValuePair<string, object> kvp;
            while ((sInput[i] != END) && (i < sInput.Length))
            {
                if (sInput[i].StartsWith(VALUE, StringComparison.OrdinalIgnoreCase))
                {
                    key = sInput[i].Split(' ')[1];
                }
                else
                {
                    kvp = new KeyValuePair<string, object>(key, sInput[i]);
                    l.Add(kvp);
                }
                i++;
            }
            return l.ToArray();
        }

        private byte[] GetResponse()
        {
            byte[] res = new byte[1024];
            MemoryStream ms = new MemoryStream();
            int cnt = stream.Read(res, 0, 1024);
            while (cnt > 0)
            {
                ms.Write(res, 0, cnt);
                if (cnt < 1024) break;
                cnt = stream.Read(res, 0, 1024);
            }
            byte[] res2 = ms.ToArray();
            ValidateErrorResponse(res2);
            return res2;
        }

        #endregion
    }
}

#endif