Question

注意：在底部澄清了我的一些问题。

我想知道是否有一个（理智的）模式来处理旧主机系统的请求/响应？在下面的示例中，IQ是请求，RSIQ是响应。在第一个示例中，我正在请求所有帐户代码的列表，在第二个请求中，我要求每个帐户代码的关闭日期。由于这些仅通过序数位置链接，因此很容易将数据拉入结构化数据类。在这种情况下，每个响应代表多个记录。

在第二个例子中，我正在为单个记录请求几位信息。在这种情况下，每个响应代表一条记录和一小部分数据点。

这是客户端发送到服务器以从数据库请求特定信息的消息。

The inquiry message has this general format:
IQ~<msg id>~A<unit#>~B<device type>~D<acct#>~F<password>~G<file>~H<hierarchicrecordpath>~J<field>

**One field from many records**:
Beginning with first share (ordinal zero) on Account 101 return all the Share ID fields in first
message then get all Close Dates in second message. IDs and Close Dates correspond
positionally within the two responses.

IQ~1~A0~BVENDOR~D101~F7777~HSHARE=0~JID=ALL

RSIQ~1~K0~JID=0000~JID=0003~JID=0004~JID=0005~JID=0025~JID=0050

IQ~1~A0~BVENDOR~D101~F7777~HSHARE=0~JCLOSEDATE=ALL

RSIQ~1~K0~JCLOSEDATE=00000000~JCLOSEDATE=20030601~JCLOSEDATE=00000000~JCLOSEDATE=00000000~JCLOSEDATE=00000000~JCLOSEDATE=00000000

**Many fields from one record**:
Using the previous requests get additional information from open shares (two examples).

IQ~1~A0~BVENDOR~D101~F7777~HSHARE#0005~JCLOSEDATE~JSHARECODE~JDIVTYPE~JBALANCE~JAVAILABLEBALANCE

RSIQ~1~K0~JCLOSEDATE=00000000~JSHARECODE=0~JDIVTYPE=2~JBALANCE=234567~JAVAILABLEBALANCE=234567

IQ~1~A0~BVENDOR~D101~F7777~HSHARE#0025~JCLOSEDATE~JSHARECODE~JDIVTYPE~JBALANCE~JAVAILABLEBALANCE

RSIQ~1~K0~JCLOSEDATE=00000000~JSHARECODE=1~JDIVTYPE=5~JBALANCE=654321~JAVAILABLEBALANCE=654321

背景：我已经在我的应用程序中使用了工作单元/存储库模式。每个应用程序都处理多个数据存储（SQL DB，文件，Web服务，套接字等）。这个想法是每个存储库都公开了（完整的）数据模型的一部分。

我最初的想法是在存储库中创建我需要的特定调用，例如GetAccounts(acctId)并让方法发送正确的请求，然后从所有<构建对象图strong>响应，最后返回对象图。

我现在正在寻找一种设计模式来处理这些方法的内部，而不需要执行大量的string.Replace（）语句或StringBuilder调用。由于任何请求的最大大小为8000个字符，因此您可以看到 ~J 字段可能变得非常复杂的位置。（我仍在寻找可以进入 ~J 字段的所有可能代码。）

小例子：

public List<SymitarAccount> GetAccounts(string accountId)
{

    var retAccounts = new List<SymitarAccount>();

    // Is there a pattern to do this repetitve but ever changing task? //
    // Example: Mock response then handle... //
    // NOTE:  There will be many request/response calls here, not just one! //
    var rsp = @"RSIQ~1~K0~JCLOSEDATE=00000000~JSHARECODE=1~JDIVTYPE=5~JBALANCE=654321~JAVAILABLEBALANCE=654321";
    var response = rsp.Split(new[] {'~'});
    foreach (var q in response)
    {
        if (q.StartsWith("J") && q.Contains("="))
        {
            // get Key Value Pair //
            // map KVP to SymitarAccount data point (big ugly switch(){}??) //
            sa.Id = // KVP for ID //
            sa.Balanace = // KVP for BALANCE //
        }
        retAccounts.Add(sa);
    }

    return retAccounts;
}

有什么想法或想法吗？

注意：我使用的是C＃（最新）。

附加＃1：

public List<SymitarAccount> GetAccounts(string accountId)
{
    var retAccounts = new List<SymitarAccount>();

    // Get all account IDs...
    var response = UnitOfWork.SendMessage("IQ~1~A0~BVENDOR~D101~F7777~HSHARE=0~JID=ALL");
    ParseResponse(response, ref retAccounts);

    // Get all account close dates (00000000 means it is open)...
    response = UnitOfWork.SendMessage("IQ~1~A0~BVENDOR~D101~F7777~HSHARE=0~JCLOSEDATE=ALL");
    ParseResponse(response, ref retAccounts);

    // Get extra info for all OPEN accounts...
    foreach (var account in retAccounts.Where(a => !a.IsClosed))
    {
        var request = "IQ~1~A0~BVENDOR~D101~F7777~HSHARE#[acct]~JCLOSEDATE~JSHARECODE~JDIVTYPE~JBALANCE~JAVAILABLEBALANCE";
        request = request.Replace("[acct]", account.Id.ToString("0000"));
        response = UnitOfWork.SendMessage(request);
        ParseResponse(response, ref retAccounts, account.Id);
    }
    return retAccounts;
}


private void ParseResponse(string response, ref List<SymitarAccount> accountList, int? id = null)
{
    var list = response.Split(new[] {'~'});
    var index = 0;
    var chain = new ChainInquiryAccountInfo();
    var parser = chain.Parser;
    foreach (var q in list.Where(q => q.StartsWith("J")))   // && q.Contains("=")))
    {
        if (accountList.Count < index || accountList[index] == null)
            accountList.Add(new SymitarAccount {PositionalIndex = index});
        var val = q.Split(new[] {'='});
        if ((id.HasValue && accountList[index].Id == id.Value) || !id.HasValue)
            accountList[index] = parser.Parse(val, accountList[index]);
        index++;
    }
}

Answer 1

您的示例实际上是反序列化，而不是来自XML或JSON，而是来自某些自定义文本格式。当您创建类并将其字段属性化以帮助序列化/反序列化时，您可以使用其他序列化程序的方向。这可以称为 Attributed Serializer Pattern 我相信......

让我们创建一些自定义属性来注释序列化类：

[AttributeUsage(AttributeTargets.All, Inherited = false, AllowMultiple = true)]
sealed class SomeDataFormatAttribute : Attribute
{
    readonly string name;

    // This is a positional argument
    public SomeDataFormatAttribute(string positionalString)
    {
        this.name = positionalString;
    }

    public string Name
    {
        get { return name; }
    }
}

然后您可以将数据对象描述为：

class SymitarAccount
{
    [SomeDataFormat("CLOSEDATE")]
    public string CloseDate;
    [SomeDataFormat("SHARECODE")]
    public int ShareCode;
}

现在您需要基于Reflection的序列化器/反序列化器，它将使用字符串匹配属性字段。这里我使用正则表达式（为简单起见，没有错误检查）：

public class SomeDataFormatDeserializer
{
    public static T Deserlize<T>(string str) where T : new()
    {
        var result = new T();

        var pattern = @"RSIQ~1~K0(?:~J(\w+=\d+))*";
        var match = Regex.Match(str, pattern);

        // Get fields of type T
        var fields = typeof(T).GetFields(BindingFlags.Public | BindingFlags.Instance);
        foreach (var field in fields)
        {
           // Get out custom attribute of this field (might return null)
           var attr = field.GetCustomAttribute(typeof(SomeDataFormatAttribute)) as SomeDataFormatAttribute;

           // Find regex capture that starts with attributed name (might return null)
           var capture = match.Groups[1].Captures
                              .Cast<Capture>()
                              .FirstOrDefault(c => c.Value.StartsWith(attr.Name));
           if (capture != null)
           {
              var stringValue = capture.Value.Split('=').Last();

              // Convert string to the proper type (like int)
              var value = Convert.ChangeType(stringValue, field.FieldType);
              field.SetValue(result, value);
           }
        }                                     
        return result;
    }
}

然后你可以像使用它一样简单：

public static List<SymitarAccount> GetAccounts(string accountId)
{
    var retAccounts = new List<SymitarAccount>();
    var responses = new List<string>() { @"RSIQ~1~K0~JCLOSEDATE=00000000~JSHARECODE=1" };
    foreach (var response in responses)
    {
        var account = SomeDataFormatDeserializer.Deserlize<SymitarAccount>(response);
        retAccounts.Add(account);
    }
    return retAccounts;
}

注意： SomeDataFormatDeserializer是为了清晰起见，而非性能。确保它可以被优化（如缓存GetFields等。）

Answer 2

我的解决方案：

属性定义：

[AttributeUsage(AttributeTargets.All, Inherited = false, AllowMultiple = true)]
internal sealed class SymitarInquiryDataFormatAttribute : Attribute
{
    private readonly string _name;

    // This is a positional argument
    public SymitarInquiryDataFormatAttribute(string positionalString) { this._name = positionalString; }

    public string Name { get { return _name; } }
}

数据类：

[Serializable]
public class SymitarAccount
{
    public int PositionalIndex;
    public bool IsClosed{get { return CloseDate.HasValue; }}

    [SymitarInquiryDataFormatAttribute("ID")]
    public int Id;
    [SymitarInquiryDataFormatAttribute("CLOSEDATE")]
    public DateTime? CloseDate;
    [SymitarInquiryDataFormatAttribute("DIVTYPE")]
    public int DivType;
    [SymitarInquiryDataFormatAttribute("BALANCE")]
    public decimal Balance;
    [SymitarInquiryDataFormatAttribute("AVAILABLEBALANCE")]
    public decimal AvailableBalance;
}

扩展：

public static class ExtensionSymitar
{
    public static List<string> ValueList(this string source, string fieldType)
    {
        var list = source.Split('~').ToList();
        return list.Where(a => a.StartsWith(fieldType)).ToList();
    }
    public static string KeyValuePairs(this string source, string fieldType)
    {
        return source.ValueList(fieldType).Aggregate(string.Empty, (current, j) => string.Format("{0}~{1}", current, j));
    }
    public static bool IsMultiRecord(this string source, string fieldType)
    {
        return source.ValueList(fieldType)
                        .Select(q => new Regex(Regex.Escape(q.Split('=').First())).Matches(source).Count > 1).First();
    }

    public static int ParseInt(this string val, string keyName)
    {
        int newValue;
        if (!int.TryParse(val, out newValue))
            throw new Exception("Could not parse " + keyName + " as an integer!");
        return newValue;
    }
    public static decimal ParseMoney(this string val, string keyName)
    {
        decimal newValue;
        if (!decimal.TryParse(val, out newValue))
            throw new Exception("Could not parse " + keyName + " as a money amount!");
        return newValue;
    }
    public static DateTime? ParseDate(this string val, string keyName)
    {
        if (val.Equals("00000000")) return null;

        var year = val.Substring(0, 4).ToInt();
        var mon = val.Substring(4, 2).ToInt();
        var day = val.Substring(6, 2).ToInt();

        if (year <= 1800 || year >= 2200 || mon < 1 || mon > 12 || day < 1 || day > 31)
            throw new Exception("Could not parse " + keyName + " as a date!");

        return new DateTime(year, mon, day);
    }
}

解串器：

public class SymitarInquiryDeserializer
{
    /// <summary>
    /// Deserializes a string of J field key value pairs
    /// </summary>
    /// <param name="str">The request or response string</param>
    /// <param name="source">Optional: Use this if you are adding data to the source object</param>
    /// <param name="fieldName">Optional: Use this if you are only populating a single property and know what it is</param>
    /// <typeparam name="T">The target class type to populate</typeparam>
    /// <returns>New T Object or optional Source Object</returns>
    public static T DeserializeFieldJ<T>(string str, T source = null, string fieldName = null) where T : class, new() 
    {
        var result = source ?? new T();

        const string pattern = @"(?:~J(\w+=\d+))*";
        var match = Regex.Match(str, pattern);

        // Get fields of type T
        var fields = typeof(T).GetFields(BindingFlags.Public | BindingFlags.Instance).ToList();

        if (fieldName != null && fieldName.StartsWith("J")) fieldName = fieldName.Replace("J", "");

        if (!fieldName.IsNullOrEmpty())
        {
            var field = fields.FirstOrDefault(a => a.Name.Equals(fieldName, StringComparison.CurrentCultureIgnoreCase));
            var stringValue = GetValue(field, match);
            if (!stringValue.IsNullOrEmpty())
                SetProperty(field, stringValue, result);
        }
        else
        {
            foreach (var field in fields)
            {
                var stringValue = GetValue(field, match);
                if(!stringValue.IsNullOrEmpty())
                    SetProperty(field, stringValue, result);
            }
        }
        return result;
    }

    private static string GetValue(FieldInfo field, Match match)
    {
        // Get out custom attribute of this field (might return null)
        var attr = field.GetCustomAttribute(typeof(SymitarInquiryDataFormatAttribute)) as SymitarInquiryDataFormatAttribute;
        if (attr == null) return null;

        // Find regex capture that starts with attributed name (might return null)
        var capture = match.Groups[1]
                            .Captures
                            .Cast<Capture>()
                            .FirstOrDefault(c => c.Value.StartsWith(attr.Name, StringComparison.CurrentCultureIgnoreCase));
        return capture == null ? null : capture.Value.Split('=').Last();
    }

    private static void SetProperty<T>(FieldInfo field, string stringValue, T result)
    {
        // Convert string to the proper type (like int)

        if (field.FieldType.FullName.Contains("Int32"))
            field.SetValue(result, stringValue.ParseInt(field.Name));
        else if (field.FieldType.FullName.Contains("Decimal"))
            field.SetValue(result, stringValue.ParseMoney(field.Name));
        else if (field.FieldType.FullName.Contains("DateTime"))
            field.SetValue(result, stringValue.ParseDate(field.Name));
        else
        {
            var value = Convert.ChangeType(stringValue, field.FieldType);
            field.SetValue(result, value);
        }
    }
}

最后，在我的存储库中：

public List<SymitarAccount> GetAccounts(string accountId)
{
    var accountList = new List<SymitarAccount>();

    // build request, get response, parse it...
    var request = "IQ~1~A20424~BAUTOPAY~D101~F7777~HSHARE=0~JID=ALL";
    var response = UnitOfWork.SendMessage(request);
    ParseResponse(response, ref accountList);

    foreach (var account in accountList.Where(a => a.IsClosed == false))
    {
        request = "IQ~1~A20424~BAUTOPAY~D101~F7777~HSHARE#" + account.Id.ToString("0000") + "~JCLOSEDATE~JSHARECODE~JDIVTYPE~JBALANCE~JAVAILABLEBALANCE";
        response = UnitOfWork.SendMessage(request);
        ParseResponse(response, ref accountList, account.Id);
    }

    return accountList;
}

private void ParseResponse(string response, ref List<SymitarAccount> accountList, int? id = null)
{
    var index = 0;
    var list = response.ValueList(fieldType: "J");
    var jString = response.KeyValuePairs(fieldType: "J");
    var isMultiRecord = response.IsMultiRecord(fieldType: "J");
    SymitarAccount account;

    if (isMultiRecord && !id.HasValue)
        foreach (var q in list.Where(a => a.StartsWith("J")))
        {
            // Add object if we don't yet have it in the collection...
            if (accountList.Count <= index)
                accountList.Add(new SymitarAccount { PositionalIndex = index });

            account = accountList.FirstOrDefault(a => a.PositionalIndex == index);
            SymitarInquiryDeserializer.DeserializeFieldJ("~" + q, account, q.Split('=').First());
            index++;
        }
    else if(id.HasValue)
    {
        account = accountList.FirstOrDefault(a => a.Id == id.Value);
        SymitarInquiryDeserializer.DeserializeFieldJ(jString, account);
    }
}

对ParseResponse的2次调用之间的区别是，在第一种情况下，我要求返回多个记录（虽然只有1个数据属性！）而在第二种情况下，我要求为单个记录请求额外的数据属性被送回。

是否有处理大型机数据的模式？

2 个答案: