com.appoptics.awslambda.handler

Class HandlerInstrumentor

java.lang.Object

com.appoptics.awslambda.handler.HandlerInstrumentor

public class HandlerInstrumentor
extends Object

Wrap the existing code logic with method instrument or instrumentChecked

Method Summary

Modifier and Type	Method and Description
static <I,O> O	instrument(I input, com.amazonaws.services.lambda.runtime.Context context, Class<?> handlerClass, Handler<O> handlerFunction) Instruments the code execution specified by the handlerFunction.
static <I> void	instrument(I input, com.amazonaws.services.lambda.runtime.Context context, Class<?> handlerClass, Procedure handlerFunction) Similar to instrument(Object, Context, Class, Handler) except that the handler function returns nothing
static <I,O,E extends Throwable> O	instrumentChecked(I input, com.amazonaws.services.lambda.runtime.Context context, Class<?> handlerClass, CheckedHandler<O,E> handlerFunction) Similar to instrument(Object, Context, Class, Handler).
static <I,E extends Throwable> void	instrumentChecked(I input, com.amazonaws.services.lambda.runtime.Context context, Class<?> handlerClass, CheckedProcedure<E> handlerFunction) Similar to instrumentChecked(Object, Context, Class, CheckedHandler) except that the handler function returns nothing

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

instrument

public static <I,O> O instrument(I input,
                                 com.amazonaws.services.lambda.runtime.Context context,
                                 Class<?> handlerClass,
                                 Handler<O> handlerFunction)

Instruments the code execution specified by the handlerFunction. This can be used by handling logic that does not implement `com.amazonaws.services.lambda.runtime.RequestHandler` For example if the original handler function is:

 
     public String handle(String input, Context context) {
         //code logic
     }
 
 

Then wrap the function by changing it to:

 
     public String handle(String input, Context context) {
         return HandlerInstrumentor.instrument(input, context, getClass(), () -> {
             //original code logic
         });
     }
 
 

Type Parameters:

I - Input type of the original handling

O - Output type of the original handling

Parameters:

input - The input for the handler, null if not available

context - The `com.amazonaws.services.lambda.runtime.Context` for this handling, null if not available

handlerClass - The handler class, usually is this.getClass(), this is optional

handlerFunction - Original code logic wrapped with `com.appoptics.awslambda.handler.Handler`

Returns:

The result from executing the handlerFunction

instrument

public static <I> void instrument(I input,
                                  com.amazonaws.services.lambda.runtime.Context context,
                                  Class<?> handlerClass,
                                  Procedure handlerFunction)

Similar to instrument(Object, Context, Class, Handler) except that the handler function returns nothing

Type Parameters:

I - Input type of the original handling

Parameters:

input - The input for the handler, null if not available

context - The `com.amazonaws.services.lambda.runtime.Context` for this handling, null if not available

handlerClass - The handler class, usually is this.getClass(), this is optional

handlerFunction - Original code logic wrapped with `com.appoptics.awslambda.handler.Procedure`

instrumentChecked

public static <I,O,E extends Throwable> O instrumentChecked(I input,
                                                            com.amazonaws.services.lambda.runtime.Context context,
                                                            Class<?> handlerClass,
                                                            CheckedHandler<O,E> handlerFunction)
                                                     throws E extends Throwable

Similar to instrument(Object, Context, Class, Handler). Except that this can be used to wrap handling code that throws checked exception

Type Parameters:

I - Input type of the original handling

O - Output type of the original handling

E - Exception type thrown of the original handling

Parameters:

input - The input for the handler, null if not available

context - The `com.amazonaws.services.lambda.runtime.Context` for this handling, null if not available

handlerClass - The handler class, usually is this.getClass(), this is optional

handlerFunction - Original code logic wrapped with `com.appoptics.awslambda.handler.CheckedHandler`

Returns:

The result from executing the handlerFunction

Throws:

E - Exception to be thrown by the original handlerFunction

E extends Throwable

instrumentChecked

public static <I,E extends Throwable> void instrumentChecked(I input,
                                                             com.amazonaws.services.lambda.runtime.Context context,
                                                             Class<?> handlerClass,
                                                             CheckedProcedure<E> handlerFunction)
                                                      throws E extends Throwable

Similar to instrumentChecked(Object, Context, Class, CheckedHandler) except that the handler function returns nothing

Type Parameters:

I - Input type of the original handling

E - Exception type thrown of the original handling

Parameters:

input - The input for the handler, null if not available

context - The `com.amazonaws.services.lambda.runtime.Context` for this handling, null if not available

handlerClass - The handler class, usually is this.getClass(), this is optional

handlerFunction - Original code logic wrapped with `com.appoptics.awslambda.handler.CheckedProcedure`

Throws:

E - Exception to be thrown by the original handlerFunction

E extends Throwable