opensim-development – Rev 1
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/*
* Copyright (c) Contributors
* See CONTRIBUTORS.TXT for a full list of copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the OpenSim Project nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
using Mono.Addins;
using System;
using System.Reflection;
using System.Threading;
using System.Text;
using System.Net;
using System.Net.Sockets;
using log4net;
using Nini.Config;
using OpenMetaverse;
using OpenMetaverse.StructuredData;
using OpenSim.Framework;
using OpenSim.Region.Framework.Interfaces;
using OpenSim.Region.Framework.Scenes;
using System.Collections.Generic;
using System.Text.RegularExpressions;
namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
{
public class JsonStore
{
private static readonly ILog m_log =
LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
protected virtual OSD ValueStore { get; set; }
protected class TakeValueCallbackClass
{
public string Path { get; set; }
public bool UseJson { get; set; }
public TakeValueCallback Callback { get; set; }
public TakeValueCallbackClass(string spath, bool usejson, TakeValueCallback cback)
{
Path = spath;
UseJson = usejson;
Callback = cback;
}
}
protected List<TakeValueCallbackClass> m_TakeStore;
protected List<TakeValueCallbackClass> m_ReadStore;
// add separators for quoted paths and array references
protected static Regex m_ParsePassOne = new Regex("({[^}]+}|\\[[0-9]+\\]|\\[\\+\\])");
// add quotes to bare identifiers which are limited to alphabetic characters
protected static Regex m_ParsePassThree = new Regex("(?<!{[^}]*)\\.([a-zA-Z]+)(?=\\.)");
// remove extra separator characters
protected static Regex m_ParsePassFour = new Regex("\\.+");
// expression used to validate the full path, this is canonical representation
protected static Regex m_ValidatePath = new Regex("^\\.(({[^}]+}|\\[[0-9]+\\]|\\[\\+\\])\\.)*$");
// expression used to match path components
protected static Regex m_PathComponent = new Regex("\\.({[^}]+}|\\[[0-9]+\\]|\\[\\+\\])");
// extract the internals of an array reference
protected static Regex m_SimpleArrayPattern = new Regex("^\\[([0-9]+)\\]$");
protected static Regex m_ArrayPattern = new Regex("^\\[([0-9]+|\\+)\\]$");
// extract the internals of a has reference
protected static Regex m_HashPattern = new Regex("^{([^}]+)}$");
// -----------------------------------------------------------------
/// <summary>
/// This is a simple estimator for the size of the stored data, it
/// is not precise, but should be close enough to implement reasonable
/// limits on the storage space used
/// </summary>
// -----------------------------------------------------------------
public int StringSpace { get; set; }
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public static bool CanonicalPathExpression(string ipath, out string opath)
{
Stack<string> path;
if (! ParsePathExpression(ipath,out path))
{
opath = "";
return false;
}
opath = PathExpressionToKey(path);
return true;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public JsonStore()
{
StringSpace = 0;
m_TakeStore = new List<TakeValueCallbackClass>();
m_ReadStore = new List<TakeValueCallbackClass>();
}
public JsonStore(string value) : this()
{
// This is going to throw an exception if the value is not
// a valid JSON chunk. Calling routines should catch the
// exception and handle it appropriately
if (String.IsNullOrEmpty(value))
ValueStore = new OSDMap();
else
ValueStore = OSDParser.DeserializeJson(value);
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public JsonStoreNodeType GetNodeType(string expr)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
return JsonStoreNodeType.Undefined;
OSD result = ProcessPathExpression(ValueStore,path);
if (result == null)
return JsonStoreNodeType.Undefined;
if (result is OSDMap)
return JsonStoreNodeType.Object;
if (result is OSDArray)
return JsonStoreNodeType.Array;
if (OSDBaseType(result.Type))
return JsonStoreNodeType.Value;
return JsonStoreNodeType.Undefined;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public JsonStoreValueType GetValueType(string expr)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
return JsonStoreValueType.Undefined;
OSD result = ProcessPathExpression(ValueStore,path);
if (result == null)
return JsonStoreValueType.Undefined;
if (result is OSDMap)
return JsonStoreValueType.Undefined;
if (result is OSDArray)
return JsonStoreValueType.Undefined;
if (result is OSDBoolean)
return JsonStoreValueType.Boolean;
if (result is OSDInteger)
return JsonStoreValueType.Integer;
if (result is OSDReal)
return JsonStoreValueType.Float;
if (result is OSDString)
return JsonStoreValueType.String;
return JsonStoreValueType.Undefined;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public int ArrayLength(string expr)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
return -1;
OSD result = ProcessPathExpression(ValueStore,path);
if (result != null && result.Type == OSDType.Array)
{
OSDArray arr = result as OSDArray;
return arr.Count;
}
return -1;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public bool GetValue(string expr, out string value, bool useJson)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
{
value = "";
return false;
}
OSD result = ProcessPathExpression(ValueStore,path);
return ConvertOutputValue(result,out value,useJson);
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public bool RemoveValue(string expr)
{
return SetValueFromExpression(expr,null);
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public bool SetValue(string expr, string value, bool useJson)
{
OSD ovalue;
// One note of caution... if you use an empty string in the
// structure it will be assumed to be a default value and will
// not be seialized in the json
if (useJson)
{
// There doesn't appear to be a good way to determine if the
// value is valid Json other than to let the parser crash
try
{
ovalue = OSDParser.DeserializeJson(value);
}
catch (Exception e)
{
if (value.StartsWith("'") && value.EndsWith("'"))
{
ovalue = new OSDString(value.Substring(1,value.Length - 2));
}
else
{
return false;
}
}
}
else
{
ovalue = new OSDString(value);
}
return SetValueFromExpression(expr,ovalue);
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public bool TakeValue(string expr, bool useJson, TakeValueCallback cback)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
return false;
string pexpr = PathExpressionToKey(path);
OSD result = ProcessPathExpression(ValueStore,path);
if (result == null)
{
m_TakeStore.Add(new TakeValueCallbackClass(pexpr,useJson,cback));
return false;
}
string value = String.Empty;
if (! ConvertOutputValue(result,out value,useJson))
{
// the structure does not match the request so i guess we'll wait
m_TakeStore.Add(new TakeValueCallbackClass(pexpr,useJson,cback));
return false;
}
SetValueFromExpression(expr,null);
cback(value);
return true;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
public bool ReadValue(string expr, bool useJson, TakeValueCallback cback)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
return false;
string pexpr = PathExpressionToKey(path);
OSD result = ProcessPathExpression(ValueStore,path);
if (result == null)
{
m_ReadStore.Add(new TakeValueCallbackClass(pexpr,useJson,cback));
return false;
}
string value = String.Empty;
if (! ConvertOutputValue(result,out value,useJson))
{
// the structure does not match the request so i guess we'll wait
m_ReadStore.Add(new TakeValueCallbackClass(pexpr,useJson,cback));
return false;
}
cback(value);
return true;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
protected bool SetValueFromExpression(string expr, OSD ovalue)
{
Stack<string> path;
if (! ParsePathExpression(expr,out path))
return false;
if (path.Count == 0)
{
ValueStore = ovalue;
StringSpace = 0;
return true;
}
// pkey will be the final element in the path, we pull it out here to make sure
// that the assignment works correctly
string pkey = path.Pop();
string pexpr = PathExpressionToKey(path);
if (pexpr != "")
pexpr += ".";
OSD result = ProcessPathExpression(ValueStore,path);
if (result == null)
return false;
// Check pkey, the last element in the path, for and extract array references
MatchCollection amatches = m_ArrayPattern.Matches(pkey,0);
if (amatches.Count > 0)
{
if (result.Type != OSDType.Array)
return false;
OSDArray amap = result as OSDArray;
Match match = amatches[0];
GroupCollection groups = match.Groups;
string akey = groups[1].Value;
if (akey == "+")
{
string npkey = String.Format("[{0}]",amap.Count);
if (ovalue != null)
{
StringSpace += ComputeSizeOf(ovalue);
amap.Add(ovalue);
InvokeNextCallback(pexpr + npkey);
}
return true;
}
int aval = Convert.ToInt32(akey);
if (0 <= aval && aval < amap.Count)
{
if (ovalue == null)
{
StringSpace -= ComputeSizeOf(amap[aval]);
amap.RemoveAt(aval);
}
else
{
StringSpace -= ComputeSizeOf(amap[aval]);
StringSpace += ComputeSizeOf(ovalue);
amap[aval] = ovalue;
InvokeNextCallback(pexpr + pkey);
}
return true;
}
return false;
}
// Check for and extract hash references
MatchCollection hmatches = m_HashPattern.Matches(pkey,0);
if (hmatches.Count > 0)
{
Match match = hmatches[0];
GroupCollection groups = match.Groups;
string hkey = groups[1].Value;
if (result is OSDMap)
{
// this is the assignment case
OSDMap hmap = result as OSDMap;
if (ovalue != null)
{
StringSpace -= ComputeSizeOf(hmap[hkey]);
StringSpace += ComputeSizeOf(ovalue);
hmap[hkey] = ovalue;
InvokeNextCallback(pexpr + pkey);
return true;
}
// this is the remove case
if (hmap.ContainsKey(hkey))
{
StringSpace -= ComputeSizeOf(hmap[hkey]);
hmap.Remove(hkey);
return true;
}
return false;
}
return false;
}
// Shouldn't get here if the path was checked correctly
m_log.WarnFormat("[JsonStore] invalid path expression");
return false;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
protected bool InvokeNextCallback(string pexpr)
{
// Process all of the reads that match the expression first
List<TakeValueCallbackClass> reads =
m_ReadStore.FindAll(delegate(TakeValueCallbackClass tb) { return pexpr.StartsWith(tb.Path); });
foreach (TakeValueCallbackClass readcb in reads)
{
m_ReadStore.Remove(readcb);
ReadValue(readcb.Path,readcb.UseJson,readcb.Callback);
}
// Process one take next
TakeValueCallbackClass takecb =
m_TakeStore.Find(delegate(TakeValueCallbackClass tb) { return pexpr.StartsWith(tb.Path); });
if (takecb != null)
{
m_TakeStore.Remove(takecb);
TakeValue(takecb.Path,takecb.UseJson,takecb.Callback);
return true;
}
return false;
}
// -----------------------------------------------------------------
/// <summary>
/// Parse the path expression and put the components into a stack. We
/// use a stack because we process the path in inverse order later
/// </summary>
// -----------------------------------------------------------------
protected static bool ParsePathExpression(string expr, out Stack<string> path)
{
path = new Stack<string>();
// add front and rear separators
expr = "." + expr + ".";
// add separators for quoted exprs and array references
expr = m_ParsePassOne.Replace(expr,".$1.",-1,0);
// add quotes to bare identifier
expr = m_ParsePassThree.Replace(expr,".{$1}",-1,0);
// remove extra separators
expr = m_ParsePassFour.Replace(expr,".",-1,0);
// validate the results (catches extra quote characters for example)
if (m_ValidatePath.IsMatch(expr))
{
MatchCollection matches = m_PathComponent.Matches(expr,0);
foreach (Match match in matches)
path.Push(match.Groups[1].Value);
return true;
}
return false;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
/// <param>path is a stack where the top level of the path is at the bottom of the stack</param>
// -----------------------------------------------------------------
protected static OSD ProcessPathExpression(OSD map, Stack<string> path)
{
if (path.Count == 0)
return map;
string pkey = path.Pop();
OSD rmap = ProcessPathExpression(map,path);
if (rmap == null)
return null;
// ---------- Check for an array index ----------
MatchCollection amatches = m_SimpleArrayPattern.Matches(pkey,0);
if (amatches.Count > 0)
{
if (rmap.Type != OSDType.Array)
{
m_log.WarnFormat("[JsonStore] wrong type for key {2}, expecting {0}, got {1}",OSDType.Array,rmap.Type,pkey);
return null;
}
OSDArray amap = rmap as OSDArray;
Match match = amatches[0];
GroupCollection groups = match.Groups;
string akey = groups[1].Value;
int aval = Convert.ToInt32(akey);
if (aval < amap.Count)
return (OSD) amap[aval];
return null;
}
// ---------- Check for a hash index ----------
MatchCollection hmatches = m_HashPattern.Matches(pkey,0);
if (hmatches.Count > 0)
{
if (rmap.Type != OSDType.Map)
{
m_log.WarnFormat("[JsonStore] wrong type for key {2}, expecting {0}, got {1}",OSDType.Map,rmap.Type,pkey);
return null;
}
OSDMap hmap = rmap as OSDMap;
Match match = hmatches[0];
GroupCollection groups = match.Groups;
string hkey = groups[1].Value;
if (hmap.ContainsKey(hkey))
return (OSD) hmap[hkey];
return null;
}
// Shouldn't get here if the path was checked correctly
m_log.WarnFormat("[JsonStore] Path type (unknown) does not match the structure");
return null;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
protected static bool ConvertOutputValue(OSD result, out string value, bool useJson)
{
value = String.Empty;
// If we couldn't process the path
if (result == null)
return false;
if (useJson)
{
// The path pointed to an intermediate hash structure
if (result.Type == OSDType.Map)
{
value = OSDParser.SerializeJsonString(result as OSDMap,true);
return true;
}
// The path pointed to an intermediate hash structure
if (result.Type == OSDType.Array)
{
value = OSDParser.SerializeJsonString(result as OSDArray,true);
return true;
}
value = "'" + result.AsString() + "'";
return true;
}
if (OSDBaseType(result.Type))
{
value = result.AsString();
return true;
}
return false;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
protected static string PathExpressionToKey(Stack<string> path)
{
if (path.Count == 0)
return "";
string pkey = "";
foreach (string k in path)
pkey = (pkey == "") ? k : (k + "." + pkey);
return pkey;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
protected static bool OSDBaseType(OSDType type)
{
// Should be the list of base types for which AsString() returns
// something useful
if (type == OSDType.Boolean)
return true;
if (type == OSDType.Integer)
return true;
if (type == OSDType.Real)
return true;
if (type == OSDType.String)
return true;
if (type == OSDType.UUID)
return true;
if (type == OSDType.Date)
return true;
if (type == OSDType.URI)
return true;
return false;
}
// -----------------------------------------------------------------
/// <summary>
///
/// </summary>
// -----------------------------------------------------------------
protected static int ComputeSizeOf(OSD value)
{
string sval;
if (ConvertOutputValue(value,out sval,true))
return sval.Length;
return 0;
}
}
// -----------------------------------------------------------------
/// <summary>
/// </summary>
// -----------------------------------------------------------------
public class JsonObjectStore : JsonStore
{
private static readonly ILog m_log =
LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
private Scene m_scene;
private UUID m_objectID;
protected override OSD ValueStore
{
get
{
SceneObjectPart sop = m_scene.GetSceneObjectPart(m_objectID);
if (sop == null)
{
// This is bad
return null;
}
return sop.DynAttrs.TopLevelMap;
}
// cannot set the top level
set
{
m_log.InfoFormat("[JsonStore] cannot set top level value in object store");
}
}
public JsonObjectStore(Scene scene, UUID oid) : base()
{
m_scene = scene;
m_objectID = oid;
// the size limit is imposed on whatever is already in the store
StringSpace = ComputeSizeOf(ValueStore);
}
}
}