/// <summary>
/// Get an element from a table by its id.
/// </summary>
/// <param name="id">
/// The id of the element.
/// </param>
/// <param name="parameters">
/// A dictionary of user-defined parameters and values to include in
/// the request URI query string.
/// </param>
/// <returns>
/// The desired element as JSON object.
/// </returns>
private async Task <JObject> GetSingleValueAsync(object id, IDictionary <string, string> parameters)
{
Arguments.IsNotNull(id, nameof(id));
// Create a query for just this item
string query = $"$filter=({MobileServiceSystemColumns.Id} eq {ODataExpressionVisitor.ToODataConstant(id)})";
// Send the query
QueryResult response = await ReadAsync(query, parameters, MobileServiceFeatures.TypedTable);
return(GetSingleValue(response));
}
/// <summary>
/// Get an element from a table by its id.
/// </summary>
/// <param name="id">
/// The id of the element.
/// </param>
/// <param name="parameters">
/// A dictionary of user-defined parameters and values to include in
/// the request URI query string.
/// </param>
/// <returns>
/// The desired element as JSON object.
/// </returns>
private async Task <JObject> GetSingleValueAsync(object id, IDictionary <string, string> parameters)
{
Debug.Assert(id != null);
// Create a query for just this item
string query = string.Format(
CultureInfo.InvariantCulture,
"$filter=({0} eq {1})",
MobileServiceSystemColumns.Id,
ODataExpressionVisitor.ToODataConstant(id));
// Send the query
QueryResult response = await this.ReadAsync(query, parameters, MobileServiceFeatures.TypedTable);
return(GetSingleValue(response));
}
/// <summary>
/// Returns the next-page token to put in the $skiptoken query option.
/// </summary>
/// <param name="enumerator">Enumerator for which the continuation token is being requested.</param>
/// <returns>The next-page token as a collection of primitive types.</returns>
public virtual object[] GetContinuationToken(IEnumerator enumerator)
{
if (this.lastReceivedPage == null)
{
return(null);
}
var operation = new ODataExpressionVisitor(this.expression).Eval();
var compound = operation as ODataCompoundQueryOperation;
if (compound != null)
{
var partial = (this.queryProvider.GetType().InvokeMember("ExecuteQuery", BindingFlags.InvokeMethod, null, this.queryProvider, new object[] { compound.AnonymousGetManyOperation }) as IEnumerable <object>).First();
compound.OfType = partial.GetType().TypeOrElementType();
compound.Keys = partial.DataServiceKeys();
}
if (operation != null)
{
operation.TopCount = 0;
operation.SkipCount = 0;
operation.ContinuationToken = null;
operation.IsCountRequest = true;
this.queryProvider.GetType().GetProperty("SkipTakeBasedPaging").SetValue(this.queryProvider, false, null);
var @return = operation is ODataSelectManyQueryOperation ? (operation as ODataSelectManyQueryOperation).NavigationPropertyType : operation.OfType;
var queryProviderType = typeof(ODataQueryProvider <>).MakeGenericType(@return);
var result = (long)queryProviderType.InvokeMember("ExecuteQuery", BindingFlags.InvokeMethod, null, this.queryProvider, new object[] { operation });
if ((this.lastReceivedPage * this.PageSizeFor(@return)) + this.CurrentOffset() >= result)
{
return(null);
}
var token = string.Format(CultureInfo.InvariantCulture, "{0}:{1}", this.entityTypeName, this.lastReceivedPage + 1);
return(new object[] { Convert.ToBase64String(Encoding.Default.GetBytes(token)) });
}
return(null);
}
/// <summary>
/// Returns the next-page token to put in the $skiptoken query option.
/// </summary>
/// <param name="enumerator">Enumerator for which the continuation token is being requested.</param>
/// <returns>The next-page token as a collection of primitive types.</returns>
public virtual object[] GetContinuationToken(IEnumerator enumerator)
{
if (this.lastReceivedPage == null)
return null;
var operation = new ODataExpressionVisitor(this.expression).Eval();
var compound = operation as ODataCompoundQueryOperation;
if (compound != null)
{
var partial = (this.queryProvider.GetType().InvokeMember("ExecuteQuery", BindingFlags.InvokeMethod, null, this.queryProvider, new object[] { compound.AnonymousGetManyOperation }) as IEnumerable<object>).First();
compound.OfType = partial.GetType().TypeOrElementType();
compound.Keys = partial.DataServiceKeys();
}
if (operation != null)
{
operation.TopCount = 0;
operation.SkipCount = 0;
operation.ContinuationToken = null;
operation.IsCountRequest = true;
this.queryProvider.GetType().GetProperty("SkipTakeBasedPaging").SetValue(this.queryProvider, false, null);
var @return = operation is ODataSelectManyQueryOperation ? (operation as ODataSelectManyQueryOperation).NavigationPropertyType : operation.OfType;
var queryProviderType = typeof(ODataQueryProvider<>).MakeGenericType(@return);
var result = (long)queryProviderType.InvokeMember("ExecuteQuery", BindingFlags.InvokeMethod, null, this.queryProvider, new object[] { operation });
if ((this.lastReceivedPage * this.PageSizeFor(@return)) + this.CurrentOffset() >= result)
return null;
var token = string.Format(CultureInfo.InvariantCulture, "{0}:{1}", this.entityTypeName, this.lastReceivedPage + 1);
return new object[] { Convert.ToBase64String(Encoding.Default.GetBytes(token)) };
}
return null;
}
/// <summary>
/// Convert the query structure into the standard OData URI protocol
/// for queries.
/// </summary>
/// <returns>
/// URI fragment representing the query.
/// </returns>
public string ToODataString()
{
char? separator = null;
StringBuilder text = new StringBuilder();
// Add the filter
if (this.Filter != null)
{
string filterStr = ODataExpressionVisitor.ToODataString(this.Filter);
text.AppendFormat(CultureInfo.InvariantCulture, "{0}{1}={2}", separator, ODataOptions.Filter, filterStr);
separator = '&';
}
// Add the ordering
if (this.Ordering.Count > 0)
{
IEnumerable <string> orderings = this.Ordering
.Select(o =>
{
string result = ODataExpressionVisitor.ToODataString(o.Expression);
if (o.Direction == OrderByDirection.Descending)
{
result += " desc";
}
return(result);
});
text.AppendFormat(CultureInfo.InvariantCulture, "{0}{1}={2}", separator, ODataOptions.OrderBy, string.Join(",", orderings.ToArray()));
separator = '&';
}
// Skip any elements
if (this.Skip.HasValue && this.Skip >= 0)
{
text.AppendFormat(CultureInfo.InvariantCulture, "{0}{1}={2}", separator, ODataOptions.Skip, this.Skip);
separator = '&';
}
// Take the desired number of elements
if (this.Top.HasValue && this.Top >= 0)
{
text.AppendFormat(CultureInfo.InvariantCulture, "{0}{1}={2}", separator, ODataOptions.Top, this.Top);
separator = '&';
}
// Add the selection
if (this.Selection.Count > 0)
{
text.AppendFormat(CultureInfo.InvariantCulture, "{0}{1}={2}", separator, ODataOptions.Select, string.Join(",", this.Selection.Select <string, string>(Uri.EscapeDataString).ToArray <string>()));
separator = '&';
}
// Add the total count
if (this.IncludeTotalCount)
{
text.AppendFormat(CultureInfo.InvariantCulture, "{0}{1}=allpages", separator, ODataOptions.InlineCount);
separator = '&';
}
return(text.ToString());
}
public void ToODataString_Null_ReturnsEmpty()
{
Assert.Equal("", ODataExpressionVisitor.ToODataString(null));
}
