versaplexd/vxdbusschema.cs

   1 using System;
   2 using System.Linq;
   3 using System.Collections;
   4 using System.Collections.Generic;
   5 using Wv;
   6 using Wv.Extensions;
   7
   8 // An ISchemaBackend that uses a DBus connection to Versaplex as a backing
   9 // store.
  10 [WvMoniker]
  11 internal class VxDbusSchema : ISchemaBackend
  12 {
  13     WvDbus bus;
  14
  15     public static void wvmoniker_register()
  16     {
  17         WvMoniker<ISchemaBackend>.register("vx",
  18                   (string m, object o) => new VxDbusSchema(m));
  19     }
  20
  21     public VxDbusSchema()
  22         : this((string)null)
  23     {
  24     }
  25
  26     public VxDbusSchema(string bus_moniker)
  27     {
  28         if (bus_moniker.e())
  29             bus = WvDbus.session_bus;
  30         else
  31             bus = new WvDbus(bus_moniker);
  32     }
  33
  34     // If you've already got a Bus you'd like to use.
  35     public VxDbusSchema(WvDbus _bus)
  36     {
  37         bus = _bus;
  38     }
  39
  40     public void Dispose()
  41     {
  42         using (bus)
  43         {
  44             bus = null;
  45         }
  46     }
  47
  48     static WvDbusMsg methodcall(string method, string signature)
  49     {
  50         return new WvDbusCall("vx.versaplexd", "/db",
  51                               "vx.db", method, signature);
  52     }
  53
  54     //
  55     // The ISchema interface
  56     //
  57
  58     // Note: this implementation ignores the sums.
  59     public VxSchemaErrors Put(VxSchema schema, VxSchemaChecksums sums,
  60         VxPutOpts opts)
  61     {
  62         WvDbusMsg call = methodcall("PutSchema",
  63             String.Format("{0}i", VxSchema.GetDbusSignature()));
  64
  65         WvDbusWriter writer = new WvDbusWriter();
  66
  67         schema.WriteSchema(writer);
  68         writer.Write((int)opts);
  69         call.Body = writer.ToArray();
  70
  71         WvDbusMsg reply = bus.send_and_wait(call);
  72         if (reply.signature == VxSchemaErrors.GetDbusSignature())
  73             return new VxSchemaErrors(reply.iter().pop());
  74         else
  75             reply.check(VxSchemaErrors.GetDbusSignature());
  76         return null;
  77     }
  78
  79     // Utility API so you can say Get("foo").
  80     public VxSchema Get(params string[] keys)
  81     {
  82         WvDbusMsg call = methodcall("GetSchema", "as");
  83
  84         WvDbusWriter writer = new WvDbusWriter();
  85
  86         if (keys == null)
  87             keys = new string[0];
  88
  89         writer.WriteArray(4, keys, (w2, k) => {
  90             w2.Write(k);
  91         });
  92         call.Body = writer.ToArray();
  93
  94         WvDbusMsg reply = bus.send_and_wait(call);
  95         reply.check("a(sssy)");
  96         VxSchema schema = new VxSchema(reply.iter().pop());
  97         return schema;
  98     }
  99
 100     public VxSchema Get(IEnumerable<string> keys)
 101     {
 102         if (keys == null)
 103             keys = new string[0];
 104         return Get(keys.ToArray());
 105     }
 106
 107     public VxSchemaChecksums GetChecksums()
 108     {
 109         WvDbusMsg call = methodcall("GetSchemaChecksums", "");
 110
 111         WvDbusMsg reply = bus.send_and_wait(call);
 112         reply.check("a(sat)");
 113         VxSchemaChecksums sums = new VxSchemaChecksums(reply);
 114         return sums;
 115     }
 116
 117     public VxSchemaErrors DropSchema(IEnumerable<string> keys)
 118     {
 119         if (keys == null)
 120             keys = new string[0];
 121         return DropSchema(keys.ToArray());
 122     }
 123
 124     // A method exported over DBus but not exposed in ISchemaBackend
 125     public VxSchemaErrors DropSchema(params string[] keys)
 126     {
 127         WvDbusMsg call = methodcall("DropSchema", "as");
 128
 129         WvDbusWriter writer = new WvDbusWriter();
 130
 131         writer.WriteArray(4, keys, (w2, k) => {
 132             w2.Write(k);
 133         });
 134         call.Body = writer.ToArray();
 135
 136         WvDbusMsg reply = bus.send_and_wait(call);
 137         if (reply.signature == VxSchemaErrors.GetDbusSignature())
 138             return new VxSchemaErrors(reply.iter().pop());
 139         else
 140             reply.check(VxSchemaErrors.GetDbusSignature());
 141         return null;
 142     }
 143
 144     public string GetSchemaData(string tablename, int seqnum, string where)
 145     {
 146         WvDbusMsg call = methodcall("GetSchemaData", "ss");
 147
 148         WvDbusWriter writer = new WvDbusWriter();
 149
 150         if (where == null)
 151             where = "";
 152
 153         writer.Write(tablename);
 154         writer.Write(where);
 155         call.Body = writer.ToArray();
 156
 157         WvDbusMsg reply = bus.send_and_wait(call);
 158         reply.check("s");
 159         return reply.iter().pop();
 160     }
 161
 162     public void PutSchemaData(string tablename, string text, int seqnum)
 163     {
 164         WvDbusMsg call = methodcall("PutSchemaData", "ss");
 165
 166         WvDbusWriter writer = new WvDbusWriter();
 167
 168         writer.Write(tablename);
 169         writer.Write(text);
 170         call.Body = writer.ToArray();
 171
 172         WvDbusMsg reply = bus.send_and_wait(call);
 173         reply.check("");
 174     }
 175 }
 176
 177