Qfyilyi

I use below code to create GameClient in Unity3d:

AmazonGameLiftClient client = 

        new AmazonGameLiftClient("accessKeyId",

                                 "accessKey",

                                  RegionEndpoint.CNNorth1);

Above code is the first line in Awake(), no any other leading codes.

I get below error:

NullReferenceException: Object reference not set to an instance of an object

Amazon.CSMSection.get_CSMEnabled ()

Amazon.Util.CSMConfig.Configure (Amazon.CSMSection section)

Amazon.Util.Internal.RootConfig..ctor ()

Amazon.AWSConfigs..cctor ()

Rethrow as TypeInitializationException: An exception was thrown by the type initializer for Amazon.AWSConfigs

Amazon.Runtime.ClientConfig..ctor ()

Amazon.GameLift.AmazonGameLiftConfig..ctor ()

Amazon.GameLift.AmazonGameLiftClient..ctor (System.String awsAccessKeyId, System.String awsSecretAccessKey, Amazon.RegionEndpoint region)

Is there anything I forgot to do?
I assume the root cause is I do not put app.config in the correct place.
So AWS SDK does not init correctly, but I have not found any tutorial for using Unity3d as Amazon GameLift client :(

My Environment:

• OS: Mac OS X 10.14.1


• Unity3d: 2018.2.12f1


• AWS SDK Core: 3.3.29.10(.net35)


• AWS SDK GameLift: 3.3.12.29(.net35)

Update:
The AWS SDK relies on System.ConfigurationManager which seems not available in Unity3d projects. It seems the root cause of the NullReferenceException.

After googling a lot, It seems the only way to resolve this problem is using reflection.

The root cause of the exception is when creating a GameLiftClient, AWS SDK tries to get AWSConfig from app.config. But there is no app.config in a Unity3d project.
So my solution is injecting one to the ConfigurationManager.

Below is the code:

String path = Path.Combine(Application.dataPath, "aws.config");

ExeConfigurationFileMap configMap = 

        new ExeConfigurationFileMap {ExeConfigFilename = path};

Configuration awsConfig = ConfigurationManager

        .OpenMappedExeConfiguration(configMap, ConfigurationUserLevel.None);



Type type = typeof(ConfigurationManager).Assembly

        .GetType("System.Configuration.ClientConfigurationSystem");

var clientConfigSystem = Activator.CreateInstance(type, true);



type.GetField("cfg", BindingFlags.NonPublic | BindingFlags.Instance)

        .SetValue(clientConfigSystem, awsConfig);



typeof(ConfigurationManager)

        .GetField("configSystem",

                BindingFlags.Static | BindingFlags.NonPublic)

        .SetValue(null,

                clientConfigSystem);

And place the "aws.config" under Assets directory of Unity3d Project.
Below is my "aws.config":

<configuration>

  <configSections>

      <section name="aws" type="Amazon.AWSSection, AWSSDK.Core"/>

      <section name="system.diagnostics" type="System.Diagnostics.DiagnosticsConfigurationHandler" />

  </configSections>

  <aws>

    <logging logTo="Log4Net"/>

    <csmConfig csmEnabled="false"/>

  </aws>

  <system.diagnostics>

     <trace autoflush="true" />

  </system.diagnostics>

</configuration>

Then I can create the AmazonGameLiftClient successfully.

The fields name used in reflection may be different if you use another version of the ".Net Framework".