/// <summary>
/// Pushes an arbitrary payload to every device matching target. This is shorthand for:
///
/// <code>
/// var push = new AVPush();
/// push.Query = query
/// push.Data = data;
/// return push.SendAsync();
/// </code>
/// </summary>
/// <param name="data">A push payload. See the AVPush.Data property for more information.</param>
/// <param name="query">A query filtering the devices which should receive this Push Notification.</param>
public static Task SendDataAsync(IDictionary <string, object> data, AVQuery <AVInstallation> query)
{
var push = new AVPush();
push.Query = query;
push.Data = data;
return(push.SendAsync());
}
/// <summary>
/// Pushes a simple message to every device matching the target query. This is shorthand for:
///
/// <code>
/// var push = new AVPush();
/// push.Query = query;
/// push.Data = new Dictionary<string, object>{{"alert", alert}};
/// return push.SendAsync();
/// </code>
/// </summary>
/// <param name="alert">The alert message to send.</param>
/// <param name="query">A query filtering the devices which should receive this Push Notification.</param>
public static Task SendAlertAsync(string alert, AVQuery <AVInstallation> query)
{
var push = new AVPush();
push.Query = query;
push.Alert = alert;
return(push.SendAsync());
}
/// <summary>
/// Filters a query based upon the predicate provided.
/// </summary>
/// <typeparam name="TSource">The type of AVObject being queried for.</typeparam>
/// <param name="source">The base <see cref="AVQuery{TSource}"/> to which
/// the predicate will be added.</param>
/// <param name="predicate">A function to test each AVObject for a condition.
/// The predicate must be able to be represented by one of the standard Where
/// functions on AVQuery</param>
/// <returns>A new AVQuery whose results will match the given predicate as
/// well as the Source's filters.</returns>
public static AVQuery <TSource> Where <TSource>(
this AVQuery <TSource> source, Expression <Func <TSource, bool> > predicate)
where TSource : AVObject
{
// Handle top-level logic operators && and ||
var binaryExpression = predicate.Body as BinaryExpression;
if (binaryExpression != null)
{
if (binaryExpression.NodeType == ExpressionType.AndAlso)
{
return(source
.Where(Expression.Lambda <Func <TSource, bool> >(
binaryExpression.Left, predicate.Parameters))
.Where(Expression.Lambda <Func <TSource, bool> >(
binaryExpression.Right, predicate.Parameters)));
}
if (binaryExpression.NodeType == ExpressionType.OrElse)
{
var left = source.Where(Expression.Lambda <Func <TSource, bool> >(
binaryExpression.Left, predicate.Parameters));
var right = source.Where(Expression.Lambda <Func <TSource, bool> >(
binaryExpression.Right, predicate.Parameters));
return(left.Or(right));
}
}
var normalized = new WhereNormalizer().Visit(predicate.Body);
var methodCallExpr = normalized as MethodCallExpression;
if (methodCallExpr != null)
{
return(source.WhereMethodCall(predicate, methodCallExpr));
}
var binaryExpr = normalized as BinaryExpression;
if (binaryExpr != null)
{
return(source.WhereBinaryExpression(predicate, binaryExpr));
}
var unaryExpr = normalized as UnaryExpression;
if (unaryExpr != null && unaryExpr.NodeType == ExpressionType.Not)
{
var node = unaryExpr.Operand as MethodCallExpression;
if (IsParseObjectGet(node) && (node.Type == typeof(bool) || node.Type == typeof(bool?)))
{
// This is a raw boolean field access like 'where !obj.Get<bool>("foo")'
return(source.WhereNotEqualTo(GetValue(node.Arguments[0]) as string, true));
}
}
throw new InvalidOperationException(
"Encountered an unsupported expression for ParseQueries.");
}
/// <summary>
/// Adds a constraint to the query that requires that a particular key's value
/// matches another AVQuery. This only works on keys whose values are
/// AVObjects or lists of AVObjects.
/// </summary>
/// <param name="key">The key to check.</param>
/// <param name="query">The query that the value should match.</param>
/// <returns>A new query with the additional constraint.</returns>
public AVQuery <T> WhereMatchesQuery <TOther>(string key, AVQuery <TOther> query)
where TOther : AVObject
{
return(new AVQuery <T>(this, where : new Dictionary <string, object> {
{ key, new Dictionary <string, object> {
{ "$inQuery", query.BuildParameters(true) }
} }
}));
}
/// <summary>
/// Adds a constraint to the query that requires that a particular key's value
/// matches another AVQuery. This only works on keys whose values are
/// AVObjects or lists of AVObjects.
/// </summary>
/// <param name="key">The key to check.</param>
/// <param name="query">The query that the value should match.</param>
/// <returns>A new query with the additional constraint.</returns>
public virtual S WhereMatchesQuery <TOther>(string key, AVQuery <TOther> query)
where TOther : AVObject
{
return(CreateInstance(this, where : new Dictionary <string, object> {
{ key, new Dictionary <string, object> {
{ "$inQuery", query.BuildParameters(true) }
} }
}));
}
/// <summary>
/// Private constructor for composition of queries. A Source query is required,
/// but the remaining values can be null if they won't be changed in this
/// composition.
/// </summary>
private AVQuery(AVQuery <T> source,
IDictionary <string, object> where = null,
IEnumerable <string> replacementOrderBy = null,
IEnumerable <string> thenBy = null,
int?skip = null,
int?limit = null,
IEnumerable <string> includes = null,
IEnumerable <string> selectedKeys = null,
String redirectClassNameForKey = null)
: base(source, where, replacementOrderBy, thenBy, skip, limit, includes, selectedKeys, redirectClassNameForKey)
{
}
internal override AVQuery <T> CreateInstance(
AVQuery <T> source,
IDictionary <string, object> where = null,
IEnumerable <string> replacementOrderBy = null,
IEnumerable <string> thenBy = null,
int?skip = null,
int?limit = null,
IEnumerable <string> includes = null,
IEnumerable <string> selectedKeys = null,
String redirectClassNameForKey = null)
{
return(new AVQuery <T>(this, where, replacementOrderBy, thenBy, skip, limit, includes, selectedKeys, redirectClassNameForKey));
}
/// <summary>
/// Adds a constraint to the query that requires a particular key's value
/// does not match any value for a key in the results of another AVQuery.
/// </summary>
/// <param name="key">The key whose value is being checked.</param>
/// <param name="keyInQuery">The key in the objects from the subquery to look in.</param>
/// <param name="query">The subquery to run</param>
/// <returns>A new query with the additional constraint.</returns>
public AVQuery <T> WhereDoesNotMatchesKeyInQuery <TOther>(string key,
string keyInQuery,
AVQuery <TOther> query) where TOther : AVObject
{
var parameters = new Dictionary <string, object> {
{ "query", query.BuildParameters(true) },
{ "key", keyInQuery }
};
return(new AVQuery <T>(this, where : new Dictionary <string, object> {
{ key, new Dictionary <string, object> {
{ "$dontSelect", parameters }
} }
}));
}
/// <summary>
/// Adds a constraint to the query that requires a particular key's value
/// to match a value for a key in the results of another AVQuery.
/// </summary>
/// <param name="key">The key whose value is being checked.</param>
/// <param name="keyInQuery">The key in the objects from the subquery to look in.</param>
/// <param name="query">The subquery to run</param>
/// <returns>A new query with the additional constraint.</returns>
public virtual S WhereMatchesKeyInQuery <TOther>(string key,
string keyInQuery,
AVQuery <TOther> query) where TOther : AVObject
{
var parameters = new Dictionary <string, object> {
{ "query", query.BuildParameters(true) },
{ "key", keyInQuery }
};
return(CreateInstance(this, where : new Dictionary <string, object> {
{ key, new Dictionary <string, object> {
{ "$select", parameters }
} }
}));
}
/// <summary>
/// Converts a normalized binary expression into the appropriate AVQuery clause.
/// </summary>
private static AVQuery <T> WhereBinaryExpression <T>(
this AVQuery <T> source, Expression <Func <T, bool> > expression, BinaryExpression node)
where T : AVObject
{
var leftTransformed = new ObjectNormalizer().Visit(node.Left) as MethodCallExpression;
if (!(IsParseObjectGet(leftTransformed) &&
leftTransformed.Object == expression.Parameters[0]))
{
throw new InvalidOperationException(
"Where expressions must have one side be a field operation on a AVObject.");
}
var fieldPath = GetValue(leftTransformed.Arguments[0]) as string;
var filterValue = GetValue(node.Right);
if (filterValue != null && !AVEncoder.IsValidType(filterValue))
{
throw new InvalidOperationException(
"Where clauses must use types compatible with AVObjects.");
}
switch (node.NodeType)
{
case ExpressionType.GreaterThan:
return(source.WhereGreaterThan(fieldPath, filterValue));
case ExpressionType.GreaterThanOrEqual:
return(source.WhereGreaterThanOrEqualTo(fieldPath, filterValue));
case ExpressionType.LessThan:
return(source.WhereLessThan(fieldPath, filterValue));
case ExpressionType.LessThanOrEqual:
return(source.WhereLessThanOrEqualTo(fieldPath, filterValue));
case ExpressionType.Equal:
return(source.WhereEqualTo(fieldPath, filterValue));
case ExpressionType.NotEqual:
return(source.WhereNotEqualTo(fieldPath, filterValue));
default:
throw new InvalidOperationException(
"Where expressions do not support this operator.");
}
}
/// <summary>
/// Constructs a AVObject whose id is already known by fetching data
/// from the server.
/// </summary>
/// <param name="objectId">ObjectId of the AVObject to fetch.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>The AVObject for the given objectId.</returns>
public Task <T> GetAsync(string objectId, CancellationToken cancellationToken)
{
AVQuery <T> singleItemQuery = new AVQuery <T>(className).
WhereEqualTo("objectId", objectId);
singleItemQuery = new AVQuery <T>(singleItemQuery, includes: this.includes, selectedKeys: this.selectedKeys, limit: 1);
return(singleItemQuery.FindAsync(cancellationToken).OnSuccess(t =>
{
var result = t.Result.FirstOrDefault();
if (result == null)
{
throw new AVException(AVException.ErrorCode.ObjectNotFound,
"Object with the given objectId not found.");
}
return result;
}));
}
/// <summary>
/// Private constructor for composition of queries. A source query is required,
/// but the remaining values can be null if they won't be changed in this
/// composition.
/// </summary>
private AVQuery(AVQuery <T> source,
IDictionary <string, object> where = null,
IEnumerable <string> replacementOrderBy = null,
IEnumerable <string> thenBy = null,
int?skip = null,
int?limit = null,
IEnumerable <string> includes = null,
IEnumerable <string> selectedKeys = null)
{
if (source == null)
{
throw new ArgumentNullException("source");
}
className = source.className;
this.where = source.where;
this.orderBy = source.orderBy;
this.skip = source.skip;
this.limit = source.limit;
this.includes = source.includes;
this.selectedKeys = source.selectedKeys;
if (where != null)
{
var newWhere = MergeWhereClauses(where);
this.where = new Dictionary <string, object>(newWhere);
}
if (replacementOrderBy != null)
{
this.orderBy = new ReadOnlyCollection <string>(replacementOrderBy.ToList());
}
if (thenBy != null)
{
if (this.orderBy == null)
{
throw new ArgumentException("You must call OrderBy before calling ThenBy.");
}
var newOrderBy = new List <string>(this.orderBy);
newOrderBy.AddRange(thenBy);
this.orderBy = new ReadOnlyCollection <string>(newOrderBy);
}
// Remove duplicates.
if (this.orderBy != null)
{
var newOrderBy = new HashSet <string>(this.orderBy);
this.orderBy = new ReadOnlyCollection <string>(newOrderBy.ToList <string>());
}
if (skip != null)
{
this.skip = (this.skip ?? 0) + skip;
}
if (limit != null)
{
this.limit = limit;
}
if (includes != null)
{
var newIncludes = MergeIncludes(includes);
this.includes = new ReadOnlyCollection <string>(newIncludes.ToList());
}
if (selectedKeys != null)
{
var newSelectedKeys = MergeSelectedKeys(selectedKeys);
this.selectedKeys = new ReadOnlyCollection <string>(newSelectedKeys.ToList());
}
}
/// <summary>
/// Constructs a query that is the or of the given queries.
/// </summary>
/// <typeparam name="T">The type of AVObject being queried.</typeparam>
/// <param name="source">An initial query to 'or' with additional queries.</param>
/// <param name="queries">The list of AVQueries to 'or' together.</param>
/// <returns>A query that is the or of the given queries.</returns>
public static AVQuery <T> Or <T>(this AVQuery <T> source, params AVQuery <T>[] queries)
where T : AVObject
{
return(AVQuery <T> .Or(queries.Concat(new[] { source })));
}
/// <summary>
/// Correlates the elements of two queries based on matching keys.
/// </summary>
/// <typeparam name="TOuter">The type of AVObjects of the first query.</typeparam>
/// <typeparam name="TInner">The type of AVObjects of the second query.</typeparam>
/// <typeparam name="TKey">The type of the keys returned by the key selector
/// functions.</typeparam>
/// <typeparam name="TResult">The type of the result. This must match either
/// TOuter or TInner</typeparam>
/// <param name="outer">The first query to join.</param>
/// <param name="inner">The query to join to the first query.</param>
/// <param name="outerKeySelector">A function to extract a join key from the results of
/// the first query.</param>
/// <param name="innerKeySelector">A function to extract a join key from the results of
/// the second query.</param>
/// <param name="resultSelector">A function to select either the outer or inner query
/// result to determine which query is the base query.</param>
/// <returns>A new AVQuery with a WhereMatchesQuery or WhereMatchesKeyInQuery
/// clause based upon the query indicated in the <paramref name="resultSelector"/>.</returns>
public static AVQuery <TResult> Join <TOuter, TInner, TKey, TResult>(
this AVQuery <TOuter> outer,
AVQuery <TInner> inner,
Expression <Func <TOuter, TKey> > outerKeySelector,
Expression <Func <TInner, TKey> > innerKeySelector,
Expression <Func <TOuter, TInner, TResult> > resultSelector)
where TOuter : AVObject
where TInner : AVObject
where TResult : AVObject
{
// resultSelector must select either the inner object or the outer object. If it's the inner
// object, reverse the query.
if (resultSelector.Body == resultSelector.Parameters[1])
{
// The inner object was selected.
return(inner.Join <TInner, TOuter, TKey, TInner>(
outer,
innerKeySelector,
outerKeySelector,
(i, o) => i) as AVQuery <TResult>);
}
if (resultSelector.Body != resultSelector.Parameters[0])
{
throw new InvalidOperationException("Joins must select either the outer or inner object.");
}
// Normalize both selectors
Expression outerNormalized = new ObjectNormalizer().Visit(outerKeySelector.Body);
Expression innerNormalized = new ObjectNormalizer().Visit(innerKeySelector.Body);
MethodCallExpression outerAsGet = outerNormalized as MethodCallExpression;
MethodCallExpression innerAsGet = innerNormalized as MethodCallExpression;
if (IsParseObjectGet(outerAsGet) && outerAsGet.Object == outerKeySelector.Parameters[0])
{
var outerKey = GetValue(outerAsGet.Arguments[0]) as string;
if (IsParseObjectGet(innerAsGet) && innerAsGet.Object == innerKeySelector.Parameters[0])
{
// Both are key accesses, so treat this as a WhereMatchesKeyInQuery
var innerKey = GetValue(innerAsGet.Arguments[0]) as string;
return(outer.WhereMatchesKeyInQuery(outerKey, innerKey, inner) as AVQuery <TResult>);
}
if (innerKeySelector.Body == innerKeySelector.Parameters[0])
{
// The inner selector is on the result of the query itself, so treat this as a
// WhereMatchesQuery
return(outer.WhereMatchesQuery(outerKey, inner) as AVQuery <TResult>);
}
throw new InvalidOperationException(
"The key for the joined object must be a AVObject or a field access " +
"on the AVObject.");
}
// TODO (hallucinogen): If we ever support "and" queries fully and/or support a "where this object
// matches some key in some other query" (as opposed to requiring a key on this query), we
// can add support for even more types of joins.
throw new InvalidOperationException(
"The key for the selected object must be a field access on the AVObject.");
}
/// <summary>
/// Performs a subsequent ordering of a query based upon the key selector provided.
/// </summary>
/// <typeparam name="TSource">The type of AVObject being queried for.</typeparam>
/// <typeparam name="TSelector">The type of key returned by keySelector.</typeparam>
/// <param name="source">The query to order.</param>
/// <param name="keySelector">A function to extract a key from the AVObject.</param>
/// <returns>A new AVQuery based on Source whose results will be ordered by
/// the key specified in the keySelector.</returns>
public static AVQuery <TSource> ThenByDescending <TSource, TSelector>(
this AVQuery <TSource> source, Expression <Func <TSource, TSelector> > keySelector)
where TSource : AVObject
{
return(source.ThenByDescending(GetOrderByPath(keySelector)));
}
/// <summary>
/// Converts a normalized method call expression into the appropriate AVQuery clause.
/// </summary>
private static AVQuery <T> WhereMethodCall <T>(
this AVQuery <T> source, Expression <Func <T, bool> > expression, MethodCallExpression node)
where T : AVObject
{
if (IsParseObjectGet(node) && (node.Type == typeof(bool) || node.Type == typeof(bool?)))
{
// This is a raw boolean field access like 'where obj.Get<bool>("foo")'
return(source.WhereEqualTo(GetValue(node.Arguments[0]) as string, true));
}
MethodInfo translatedMethod;
if (functionMappings.TryGetValue(node.Method, out translatedMethod))
{
var objTransformed = new ObjectNormalizer().Visit(node.Object) as MethodCallExpression;
if (!(IsParseObjectGet(objTransformed) &&
objTransformed.Object == expression.Parameters[0]))
{
throw new InvalidOperationException(
"The left-hand side of a supported function call must be a AVObject field access.");
}
var fieldPath = GetValue(objTransformed.Arguments[0]);
var containedIn = GetValue(node.Arguments[0]);
var queryType = translatedMethod.DeclaringType.GetGenericTypeDefinition()
.MakeGenericType(typeof(T));
translatedMethod = ReflectionHelpers.GetMethod(queryType,
translatedMethod.Name,
translatedMethod.GetParameters().Select(p => p.ParameterType).ToArray());
return(translatedMethod.Invoke(source, new[] { fieldPath, containedIn }) as AVQuery <T>);
}
if (node.Arguments[0] == expression.Parameters[0])
{
// obj.ContainsKey("foo") --> query.WhereExists("foo")
if (node.Method == containsKeyMethod)
{
return(source.WhereExists(GetValue(node.Arguments[1]) as string));
}
// !obj.ContainsKey("foo") --> query.WhereDoesNotExist("foo")
if (node.Method == notContainsKeyMethod)
{
return(source.WhereDoesNotExist(GetValue(node.Arguments[1]) as string));
}
}
if (node.Method.IsGenericMethod)
{
if (node.Method.GetGenericMethodDefinition() == containsMethod)
{
// obj.Get<IList<T>>("path").Contains(someValue)
if (IsParseObjectGet(node.Arguments[0] as MethodCallExpression))
{
return(source.WhereEqualTo(
GetValue(((MethodCallExpression)node.Arguments[0]).Arguments[0]) as string,
GetValue(node.Arguments[1])));
}
// someList.Contains(obj.Get<T>("path"))
if (IsParseObjectGet(node.Arguments[1] as MethodCallExpression))
{
var collection = GetValue(node.Arguments[0]) as System.Collections.IEnumerable;
return(source.WhereContainedIn(
GetValue(((MethodCallExpression)node.Arguments[1]).Arguments[0]) as string,
collection.Cast <object>()));
}
}
if (node.Method.GetGenericMethodDefinition() == notContainsMethod)
{
// !obj.Get<IList<T>>("path").Contains(someValue)
if (IsParseObjectGet(node.Arguments[0] as MethodCallExpression))
{
return(source.WhereNotEqualTo(
GetValue(((MethodCallExpression)node.Arguments[0]).Arguments[0]) as string,
GetValue(node.Arguments[1])));
}
// !someList.Contains(obj.Get<T>("path"))
if (IsParseObjectGet(node.Arguments[1] as MethodCallExpression))
{
var collection = GetValue(node.Arguments[0]) as System.Collections.IEnumerable;
return(source.WhereNotContainedIn(
GetValue(((MethodCallExpression)node.Arguments[1]).Arguments[0]) as string,
collection.Cast <object>()));
}
}
}
throw new InvalidOperationException(node.Method + " is not a supported method call in a where expression.");
}
