/// <summary>
/// Adds a field with the specified properties to this graph type.
/// </summary>
/// <typeparam name="TGraphType">The .NET type of the graph type of this field.</typeparam>
/// <param name="name">The name of the field.</param>
/// <param name="description">The description of the field.</param>
/// <param name="arguments">A list of arguments for the field.</param>
/// <param name="resolve">A field resolver delegate. Only applicable to fields of output graph types. If not specified, <see cref="NameFieldResolver"/> will be used.</param>
/// <param name="deprecationReason">The deprecation reason for the field. Applicable only for output graph types.</param>
/// <returns>The newly added <see cref="FieldType"/> instance.</returns>
public FieldType FieldDelegate <TGraphType>(
string name,
string?description = null,
QueryArguments?arguments = null,
Delegate?resolve = null,
string?deprecationReason = null)
where TGraphType : IGraphType
{
IFieldResolver?resolver = null;
if (resolve != null)
{
// create an instance expression that points to the instance represented by the delegate
// for instance, if the delegate represents obj.MyMethod,
// then the lambda would be: _ => obj
var param = Expression.Parameter(typeof(IResolveFieldContext), "context");
var body = Expression.Constant(resolve.Target, resolve.Method.DeclaringType !);
var lambda = Expression.Lambda(body, param);
resolver = AutoRegisteringHelper.BuildFieldResolver(resolve.Method, null, null, lambda);
}
return(AddField(new FieldType
{
Name = name,
Description = description,
DeprecationReason = deprecationReason,
Type = typeof(TGraphType),
Arguments = arguments,
Resolver = resolver,
}));
}
public static IServiceCollection TryAddMutationEndpoint <TGraphType>(
this IServiceCollection services,
string name,
string?description = null,
QueryArguments?arguments = null,
Delegate?resolve = null)
where TGraphType : IGraphType
{
resolve ??= new Func <object?>(() => null);
return(services.TryAddMutationEndpoint(new MutationEndpoint(name, description, typeof(TGraphType), resolve, arguments)));
}
/// <summary>
/// Adds a field with the specified properties to a specified output graph type.
/// </summary>
/// <param name="obj">The graph type to add a field to.</param>
/// <param name="name">The name of the field.</param>
/// <param name="type">The graph type of this field.</param>
/// <param name="description">The description of the field.</param>
/// <param name="arguments">A list of arguments for the field.</param>
/// <param name="resolve">A field resolver delegate. If not specified, <see cref="NameFieldResolver"/> will be used.</param>
public static void Field( //TODO: v5 - change void to T where T : IObjectGraphType
this IObjectGraphType obj,
string name,
IGraphType type,
string?description = null,
QueryArguments?arguments = null,
Func <IResolveFieldContext, object?>?resolve = null)
{
var field = new FieldType
{
Name = name,
Description = description,
Arguments = arguments,
ResolvedType = type,
Resolver = resolve != null ? new FuncFieldResolver <object>(resolve) : null
};
obj.AddField(field);
}
public static Dictionary <string, ArgumentValue>?GetArgumentValues(QueryArguments?definitionArguments, Arguments?astArguments, Variables?variables)
{
if (definitionArguments == null || definitionArguments.Count == 0)
{
return(null);
}
var values = new Dictionary <string, ArgumentValue>(definitionArguments.Count);
foreach (var arg in definitionArguments.List !)
{
var value = astArguments?.ValueFor(arg.Name);
var type = arg.ResolvedType;
values[arg.Name] = CoerceValue(type, value, variables, arg.DefaultValue);
}
return(values);
}
/// <summary>
/// Adds a field with the specified properties to this graph type.
/// </summary>
/// <typeparam name="TGraphType">The .NET type of the graph type of this field.</typeparam>
/// <typeparam name="TReturnType">The type of the return value of the field resolver delegate.</typeparam>
/// <param name="name">The name of the field.</param>
/// <param name="description">The description of the field.</param>
/// <param name="arguments">A list of arguments for the field.</param>
/// <param name="resolve">A field resolver delegate. Only applicable to fields of output graph types. If not specified, <see cref="NameFieldResolver"/> will be used.</param>
/// <param name="deprecationReason">The deprecation reason for the field. Applicable only for output graph types.</param>
/// <returns>The newly added <see cref="FieldType"/> instance.</returns>
public FieldType FieldAsync <TGraphType, TReturnType>(
string name,
string?description = null,
QueryArguments?arguments = null,
Func <IResolveFieldContext <TSourceType>, Task <TReturnType?> >?resolve = null,
string?deprecationReason = null)
where TGraphType : IGraphType
{
return(AddField(new FieldType
{
Name = name,
Description = description,
DeprecationReason = deprecationReason,
Type = typeof(TGraphType),
Arguments = arguments,
Resolver = resolve != null
? new AsyncFieldResolver <TSourceType, TReturnType>(resolve)
: null
}));
}
/// <summary>
/// Adds a field with the specified properties to this graph type.
/// </summary>
/// <param name="type">The .NET type of the graph type of this field.</param>
/// <param name="name">The name of the field.</param>
/// <param name="description">The description of the field.</param>
/// <param name="arguments">A list of arguments for the field.</param>
/// <param name="resolve">A field resolver delegate. Only applicable to fields of output graph types. If not specified, <see cref="NameFieldResolver"/> will be used.</param>
/// <param name="deprecationReason">The deprecation reason for the field. Applicable only for output graph types.</param>
/// <returns>The newly added <see cref="FieldType"/> instance.</returns>
public FieldType FieldAsync(
Type type,
string name,
string?description = null,
QueryArguments?arguments = null,
Func <IResolveFieldContext <TSourceType>, Task <object?> >?resolve = null,
string?deprecationReason = null)
{
return(AddField(new FieldType
{
Name = name,
Description = description,
DeprecationReason = deprecationReason,
Type = type,
Arguments = arguments,
Resolver = resolve != null
? new AsyncFieldResolver <TSourceType, object>(resolve)
: null
}));
}
/// <summary>
/// Adds a field with the specified properties to this graph type.
/// </summary>
/// <typeparam name="TGraphType">The .NET type of the graph type of this field.</typeparam>
/// <param name="name">The name of the field.</param>
/// <param name="description">The description of the field.</param>
/// <param name="arguments">A list of arguments for the field.</param>
/// <param name="resolve">A field resolver delegate. Only applicable to fields of output graph types. If not specified, <see cref="NameFieldResolver"/> will be used.</param>
/// <param name="deprecationReason">The deprecation reason for the field. Applicable only for output graph types.</param>
/// <returns>The newly added <see cref="FieldType"/> instance.</returns>
public FieldType FieldDelegate <TGraphType>(
string name,
string?description = null,
QueryArguments?arguments = null,
Delegate?resolve = null,
string?deprecationReason = null)
where TGraphType : IGraphType
{
return(AddField(new FieldType
{
Name = name,
Description = description,
DeprecationReason = deprecationReason,
Type = typeof(TGraphType),
Arguments = arguments,
Resolver = resolve != null
? new DelegateFieldModelBinderResolver(resolve)
: null
}));
}
internal GraphQlEndpoint(Type?hostType, string name, string?description, Type graphType, Delegate resolve, QueryArguments?arguments)
{
Name = name;
Description = description;
GraphType = graphType;
Arguments = arguments;
var targetParameter = Expression.Parameter(typeof(object), "target");
var hostParameter = Expression.Parameter(typeof(object), "host");
var contextParameter = Expression.Parameter(typeof(IResolveFieldContext), "context");
var serviceProviderParameter = Expression.Parameter(typeof(IServiceProvider), "serviceProvider");
var targetExpression = resolve.Target switch
{
not null => Expression.Convert(targetParameter, resolve.Target.GetType()),
null => null,
};
var argumentsExpressions = new List <Expression>();
var argumentsInfos = resolve.Method.GetParameters();
// setup first argument as host expression
if (hostType != null && argumentsInfos.Length >= 1 && argumentsInfos[0].ParameterType.IsAssignableFrom(hostType))
{
argumentsExpressions.Add(Expression.Convert(hostParameter, hostType));
}
// map graphql argument to arguments expressions
var getArgumentMethodInfo = typeof(GraphQL.ResolveFieldContextExtensions).GetMethods().First(m =>
m.Name == nameof(GraphQL.ResolveFieldContextExtensions.GetArgument) && m.GetGenericArguments().Length == 1);
foreach (var(parameter, index) in argumentsInfos.Skip(argumentsExpressions.Count).Take(arguments?.Count ?? 0)
.Select((value, index) => (value, index)))
{
argumentsExpressions.Add(Expression.Call(
null,
getArgumentMethodInfo.MakeGenericMethod(parameter.ParameterType),
contextParameter,
Expression.Constant(arguments ![index].Name, typeof(string)),
Expression.Default(parameter.ParameterType)));
}
public FieldType FieldSubscribeAsync <TGraphType>(
string name,
string?description = null,
QueryArguments?arguments = null,
Func <IResolveFieldContext <TSourceType>, object?>?resolve = null,
Func <IResolveEventStreamContext, Task <IObservable <object?> > >?subscribeAsync = null,
string?deprecationReason = null)
where TGraphType : IGraphType
{
return(AddField(new EventStreamFieldType
{
Name = name,
Description = description,
DeprecationReason = deprecationReason,
Type = typeof(TGraphType),
Arguments = arguments,
Resolver = resolve != null
? new FuncFieldResolver <TSourceType, object>(resolve)
: null,
AsyncSubscriber = subscribeAsync != null
? new AsyncEventStreamResolver <object>(subscribeAsync)
: null
}));
}
internal QueryEndpoint(string name, string?description, Type graphType, Delegate resolve, QueryArguments?arguments = null)
: base(null, name, description, graphType, resolve, arguments)
{
}
internal FileFieldEndpoint(string name, string?description, Type graphType, Delegate resolve, QueryArguments?arguments = null)
: base(typeof(FileHandle), name, description, graphType, resolve, arguments)
{
}