//Copyright 2010 Microsoft Corporation
//
//Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
//You may obtain a copy of the License at
//
//http://www.apache.org/licenses/LICENSE-2.0
//
//Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an
//"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//See the License for the specific language governing permissions and limitations under the License.
namespace System.Data.Services.Client{
#region Namespaces.
using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
#endregion Namespaces.
internal class UriWriter : DataServiceExpressionVisitor
{
private readonly DataServiceContext context;
private readonly StringBuilder uriBuilder;
private Version uriVersion;
private ResourceSetExpression leafResourceSet;
private UriWriter(DataServiceContext context)
{
Debug.Assert(context != null, "context != null");
this.context = context;
this.uriBuilder = new StringBuilder();
this.uriVersion = Util.DataServiceVersion1;
}
internal static void Translate(DataServiceContext context, bool addTrailingParens, Expression e, out Uri uri, out Version version)
{
var writer = new UriWriter(context);
writer.leafResourceSet = addTrailingParens ? (e as ResourceSetExpression) : null;
writer.Visit(e);
uri = Util.CreateUri(context.BaseUriWithSlash, Util.CreateUri(writer.uriBuilder.ToString(), UriKind.Relative));
version = writer.uriVersion;
}
internal override Expression VisitMethodCall(MethodCallExpression m)
{
throw Error.MethodNotSupported(m);
}
internal override Expression VisitUnary(UnaryExpression u)
{
throw new NotSupportedException(Strings.ALinq_UnaryNotSupported(u.NodeType.ToString()));
}
internal override Expression VisitBinary(BinaryExpression b)
{
throw new NotSupportedException(Strings.ALinq_BinaryNotSupported(b.NodeType.ToString()));
}
internal override Expression VisitConstant(ConstantExpression c)
{
throw new NotSupportedException(Strings.ALinq_ConstantNotSupported(c.Value));
}
internal override Expression VisitTypeIs(TypeBinaryExpression b)
{
throw new NotSupportedException(Strings.ALinq_TypeBinaryNotSupported);
}
internal override Expression VisitConditional(ConditionalExpression c)
{
throw new NotSupportedException(Strings.ALinq_ConditionalNotSupported);
}
internal override Expression VisitParameter(ParameterExpression p)
{
throw new NotSupportedException(Strings.ALinq_ParameterNotSupported);
}
internal override Expression VisitMemberAccess(MemberExpression m)
{
throw new NotSupportedException(Strings.ALinq_MemberAccessNotSupported(m.Member.Name));
}
internal override Expression VisitLambda(LambdaExpression lambda)
{
throw new NotSupportedException(Strings.ALinq_LambdaNotSupported);
}
internal override NewExpression VisitNew(NewExpression nex)
{
throw new NotSupportedException(Strings.ALinq_NewNotSupported);
}
internal override Expression VisitMemberInit(MemberInitExpression init)
{
throw new NotSupportedException(Strings.ALinq_MemberInitNotSupported);
}
internal override Expression VisitListInit(ListInitExpression init)
{
throw new NotSupportedException(Strings.ALinq_ListInitNotSupported);
}
internal override Expression VisitNewArray(NewArrayExpression na)
{
throw new NotSupportedException(Strings.ALinq_NewArrayNotSupported);
}
internal override Expression VisitInvocation(InvocationExpression iv)
{
throw new NotSupportedException(Strings.ALinq_InvocationNotSupported);
}
internal override Expression VisitNavigationPropertySingletonExpression(NavigationPropertySingletonExpression npse)
{
this.Visit(npse.Source);
this.uriBuilder.Append(UriHelper.FORWARDSLASH).Append(this.ExpressionToString(npse.MemberExpression));
this.VisitQueryOptions(npse);
return npse;
}
internal override Expression VisitResourceSetExpression(ResourceSetExpression rse)
{
if ((ResourceExpressionType)rse.NodeType == ResourceExpressionType.ResourceNavigationProperty)
{
this.Visit(rse.Source);
this.uriBuilder.Append(UriHelper.FORWARDSLASH).Append(this.ExpressionToString(rse.MemberExpression));
}
else
{
this.uriBuilder.Append(UriHelper.FORWARDSLASH).Append((string)((ConstantExpression)rse.MemberExpression).Value);
}
if (rse.KeyPredicate != null)
{
this.uriBuilder.Append(UriHelper.LEFTPAREN);
if (rse.KeyPredicate.Count == 1)
{
this.uriBuilder.Append(this.ExpressionToString(rse.KeyPredicate.Values.First()));
}
else
{
bool addComma = false;
foreach (var kvp in rse.KeyPredicate)
{
if (addComma)
{
this.uriBuilder.Append(UriHelper.COMMA);
}
this.uriBuilder.Append(kvp.Key.Name);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
this.uriBuilder.Append(this.ExpressionToString(kvp.Value));
addComma = true;
}
}
this.uriBuilder.Append(UriHelper.RIGHTPAREN);
}
else if (rse == this.leafResourceSet)
{
this.uriBuilder.Append(UriHelper.LEFTPAREN);
this.uriBuilder.Append(UriHelper.RIGHTPAREN);
}
if (rse.CountOption == CountOption.ValueOnly)
{
this.uriBuilder.Append(UriHelper.FORWARDSLASH).Append(UriHelper.DOLLARSIGN).Append(UriHelper.COUNT);
this.EnsureMinimumVersion(2, 0);
}
this.VisitQueryOptions(rse);
return rse;
}
internal void VisitQueryOptions(ResourceExpression re)
{
bool needAmpersand = false;
if (re.HasQueryOptions)
{
this.uriBuilder.Append(UriHelper.QUESTIONMARK);
ResourceSetExpression rse = re as ResourceSetExpression;
if (rse != null)
{
IEnumerator options = rse.SequenceQueryOptions.GetEnumerator();
while (options.MoveNext())
{
if (needAmpersand)
{
this.uriBuilder.Append(UriHelper.AMPERSAND);
}
Expression e = ((Expression)options.Current);
ResourceExpressionType et = (ResourceExpressionType)e.NodeType;
switch (et)
{
case ResourceExpressionType.SkipQueryOption:
this.VisitQueryOptionExpression((SkipQueryOptionExpression)e);
break;
case ResourceExpressionType.TakeQueryOption:
this.VisitQueryOptionExpression((TakeQueryOptionExpression)e);
break;
case ResourceExpressionType.OrderByQueryOption:
this.VisitQueryOptionExpression((OrderByQueryOptionExpression)e);
break;
case ResourceExpressionType.FilterQueryOption:
this.VisitQueryOptionExpression((FilterQueryOptionExpression)e);
break;
default:
Debug.Assert(false, "Unexpected expression type " + (int)et);
break;
}
needAmpersand = true;
}
}
if (re.ExpandPaths.Count > 0)
{
if (needAmpersand)
{
this.uriBuilder.Append(UriHelper.AMPERSAND);
}
this.VisitExpandOptions(re.ExpandPaths);
needAmpersand = true;
}
if (re.Projection != null && re.Projection.Paths.Count > 0)
{
if (needAmpersand)
{
this.uriBuilder.Append(UriHelper.AMPERSAND);
}
this.VisitProjectionPaths(re.Projection.Paths);
needAmpersand = true;
}
if (re.CountOption == CountOption.InlineAll)
{
if (needAmpersand)
{
this.uriBuilder.Append(UriHelper.AMPERSAND);
}
this.VisitCountOptions();
needAmpersand = true;
}
if (re.CustomQueryOptions.Count > 0)
{
if (needAmpersand)
{
this.uriBuilder.Append(UriHelper.AMPERSAND);
}
this.VisitCustomQueryOptions(re.CustomQueryOptions);
needAmpersand = true;
}
}
}
internal void VisitQueryOptionExpression(SkipQueryOptionExpression sqoe)
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONSKIP);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
this.uriBuilder.Append(this.ExpressionToString(sqoe.SkipAmount));
}
internal void VisitQueryOptionExpression(TakeQueryOptionExpression tqoe)
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONTOP);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
this.uriBuilder.Append(this.ExpressionToString(tqoe.TakeAmount));
}
internal void VisitQueryOptionExpression(FilterQueryOptionExpression fqoe)
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONFILTER);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
this.uriBuilder.Append(this.ExpressionToString(fqoe.Predicate));
}
internal void VisitQueryOptionExpression(OrderByQueryOptionExpression oboe)
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONORDERBY);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
int ii = 0;
while (true)
{
var selector = oboe.Selectors[ii];
this.uriBuilder.Append(this.ExpressionToString(selector.Expression));
if (selector.Descending)
{
this.uriBuilder.Append(UriHelper.SPACE);
this.uriBuilder.Append(UriHelper.OPTIONDESC);
}
if (++ii == oboe.Selectors.Count)
{
break;
}
this.uriBuilder.Append(UriHelper.COMMA);
}
}
internal void VisitExpandOptions(List<string> paths)
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONEXPAND);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
int ii = 0;
while (true)
{
this.uriBuilder.Append(paths[ii]);
if (++ii == paths.Count)
{
break;
}
this.uriBuilder.Append(UriHelper.COMMA);
}
}
internal void VisitProjectionPaths(List<string> paths)
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONSELECT);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
int ii = 0;
while (true)
{
string path = paths[ii];
this.uriBuilder.Append(path);
if (++ii == paths.Count)
{
break;
}
this.uriBuilder.Append(UriHelper.COMMA);
}
this.EnsureMinimumVersion(2, 0);
}
internal void VisitCountOptions()
{
this.uriBuilder.Append(UriHelper.DOLLARSIGN);
this.uriBuilder.Append(UriHelper.OPTIONCOUNT);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
this.uriBuilder.Append(UriHelper.COUNTALL);
this.EnsureMinimumVersion(2, 0);
}
internal void VisitCustomQueryOptions(Dictionary<ConstantExpression, ConstantExpression> options)
{
List<ConstantExpression> keys = options.Keys.ToList();
List<ConstantExpression> values = options.Values.ToList();
int ii = 0;
while (true)
{
this.uriBuilder.Append(keys[ii].Value);
this.uriBuilder.Append(UriHelper.EQUALSSIGN);
this.uriBuilder.Append(values[ii].Value);
if (keys[ii].Value.ToString().Equals(UriHelper.DOLLARSIGN + UriHelper.OPTIONCOUNT, StringComparison.OrdinalIgnoreCase))
{
this.EnsureMinimumVersion(2, 0);
}
if (++ii == keys.Count)
{
break;
}
this.uriBuilder.Append(UriHelper.AMPERSAND);
}
}
private string ExpressionToString(Expression expression)
{
return ExpressionWriter.ExpressionToString(this.context, expression);
}
private void EnsureMinimumVersion(int major, int minor)
{
if (major > this.uriVersion.Major ||
(major == this.uriVersion.Major && minor > this.uriVersion.Minor))
{
this.uriVersion = new Version(major, minor);
}
}
}
}
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