SAHB.GraphQL.Client

Query HTTP api using GraphQL. The client recieves a model as typeparameter and then queries the GraphQL api and deserilize the result.

Nuget

The library can be found on NuGet with the package name SAHB.GraphQL.Client. For pre release builds the NuGet package feed from AppVeyor can be used.

Older versions (1.1 and later) can be found on SAHB.GraphQLClient.

It can be installed using the following command in the Package Manager Console.

Install-Package SAHB.GraphQL.Client

The client supports the following frameworks:

SAHB.GraphQL.Client:

• .NET Standard 1.2
• .NET Framework 4.5.2

SAHB.GraphQL.Client.Subscription:

• .NET Standard 2.0
• .NET Framework 4.5.2

Documentation

Documentation can be found in this readme and in Documentation.md file.

Building

In order to build this project some additional steps is needed to generate a Version.props file. The easiest way is to execute the following commands:

git submodule update --init --recursive
cd Build
.\build.ps1 -Target "Build"

Another way is creating the file Version.props. The file should be at the root directory of the repository and contain the following:

<Project>
	<PropertyGroup>
		<Version>2.1.0-unstablebuild</Version>
	</PropertyGroup>
</Project>

Examples

An example for the Starwars API.

// TODO: Use dependency injection (services.AddGraphQLHttpClient()) (IServiceCollection)
// Initilize GraphQLClient
IGraphQLHttpClient client = GraphQLHttpClient.Default();

// Get response from url
var response = await client.Query<Query>("https://mpjk0plp9.lp.gql.zone/graphql");

// Get name etc.
Console.WriteLine(response.Hero.Name);

The example uses the following query classes:

public class Query
{
   public CharacterOrPerson Hero { get; set; }
}
        
public class CharacterOrPerson
{
   public string Name { get; set; }
   public IEnumerable<Friend> Friends { get; set; }
}

public class Friend
{
   public string Name { get; set; }
}

The following code requests the endpoint with the following query

{"query":"query{hero{name friends{name}}}"} 

The following using statements is required

using SAHB.GraphQLClient;
using SAHB.GraphQLClient.Extentions;

More examples can be found in Examples.md

Arguments

It's possible to add arguments to queries. This can be done with the attribute GraphQLArgumentAttribute. This attribute takes 3 arguments where the first is argument name used on the GraphQL server. The second is the argument type, for example String. The third argument is the varible name which should be used when the query is requested.

public class Query
{
   [GraphQLArgumentAttribute("argumentName", "ArgumentType", "variableName")]
   public Hero Hero { get; set; }
}

The client is requested as shown here:

var response = await client.Query<Query>("https://mpjk0plp9.lp.gql.zone/graphql", 
   arguments: new GraphQLQueryArgument("variableName", "valueToBeSent"});

This will generate the query (Hero contains here only the Name property):

{"query":"query{hero(argumentName:\"valueToBeSent\"){name}}"}

Renaming of a field

To rename a field name use the attribute GraphQLFieldNameAttribute on the class or property which you want to remap. For example request the field Fullname on the property Name do the follwing.

public class Friend
{
   [GraphQLFieldName("fullname")
   public string Name { get; set; }
}

This will generate the query:

{"query":"query{hero{Name:fullname"}

Note: For generating this you need to remember to add a extra Query class

public class Query
{
   public Hero Hero { get; set; }
}

Ignoring a field

To ignore a field use the attribute GraphQLFieldIgnoreAttribute on the class or property which you want to ignore. For example:

public class Hero
{
   public string Name { get; set; }

   [GraphQLFieldIgnore]
   public string IgnoredField { get; set; }
}

Example for ignoring a class

public class Hero
{
   public string Name { get; set; }

   public IgnoredClass IgnoredField { get; set; }
}

[GraphQLFieldIgnore]
public class IgnoredClass
{
   public string SomeProperty { get; set; }
}

This will generate the query:

{"query":"query{hero{name}}"}

Note: For generating this you need to remember to add a extra Query class

public class Query
{
   public Hero Hero { get; set; }
}

Subscriptions

The GraphQLclient has a subscription client which can be found here: SAHB.GraphQLClient.Subscription. Documentation can be found in Documentation.md file.

Introspection

The GraphQLclient has a package which contains a introspection query to inspect the GraphQL type system and a validator to validate C# queries against the introspection output. It can be found here: SAHB.GraphQLClient.Introspection. Documentation can be found in Documentation.md file.

Example projects

Example projects can be found in the path examples