Dependency injection hooks

src/main/java/com/microsoft/azure/functions/worker/binding/ExecutionContextDataSource.java

@@ -3,26 +3,32 @@
 import java.util.logging.Logger;
 
 import com.microsoft.azure.functions.ExecutionContext;
+import com.microsoft.azure.functions.middleware.MiddlewareExecutionContext;
 import com.microsoft.azure.functions.worker.WorkerLogManager;
 import com.microsoft.azure.functions.TraceContext;
 import com.microsoft.azure.functions.RetryContext;
+import com.microsoft.azure.functions.worker.broker.FunctionMethodExecutorImpl;
+import com.microsoft.azure.functions.worker.broker.JavaMethodExecutor;
 
-public final class ExecutionContextDataSource extends DataSource<ExecutionContext> implements ExecutionContext {
+public final class ExecutionContextDataSource extends DataSource<ExecutionContext> implements MiddlewareExecutionContext {
 
     private final String invocationId;
     private final TraceContext traceContext;
     private final RetryContext retryContext;
     private final Logger logger;
     private final String funcname;
     private BindingDataStore dataStore;
+    private final JavaMethodExecutor executor;
+    private Object functionInstance;
 
-    public ExecutionContextDataSource(String invocationId, String funcname, TraceContext traceContext, RetryContext retryContext) {
+    public ExecutionContextDataSource(JavaMethodExecutor executor, String invocationId, String funcname, TraceContext traceContext, RetryContext retryContext) {
         super(null, null, EXECONTEXT_DATA_OPERATIONS);
         this.invocationId = invocationId;
         this.traceContext = traceContext;
         this.retryContext = retryContext;
         this.logger = WorkerLogManager.getInvocationLogger(invocationId);
         this.funcname = funcname;
+        this.executor = executor;
         this.setValue(this);
     }
 
@@ -49,6 +55,26 @@ public void setDataStore(BindingDataStore dataStore) {
         this.dataStore = dataStore;
     }
 
+    @Override
+    public ClassLoader getFunctionClassLoader() {
+        return executor.getClassLoader();
+    }
+
+    @Override
+    public Class getFunctionClass() {
+        return executor.getContainingClass();
+    }
+
+    @Override
+    public Object getFunctionInstance() {
+        return functionInstance;
+    }
+
+    @Override
+    public void setFunctionInstance(Object obj) {
+        this.functionInstance = obj;
+    }
+
     private static final DataOperations<ExecutionContext, Object> EXECONTEXT_DATA_OPERATIONS = new DataOperations<>();
     static {
         EXECONTEXT_DATA_OPERATIONS.addGenericOperation(ExecutionContext.class, DataOperations::generalAssignment);

src/main/java/com/microsoft/azure/functions/worker/broker/FunctionMethodExecutorImpl.java

@@ -53,13 +53,29 @@ public void execute(ExecutionContextDataSource executionContextDataSource) throw
             BindingDataStore dataStore = executionContextDataSource.getDataStore();
             Object retValue = this.overloadResolver.resolve(dataStore)
                     .orElseThrow(() -> new NoSuchMethodException("Cannot locate the method signature with the given input"))
-                    .invoke(() -> this.containingClass.newInstance());
+                    .invoke(() -> {
+                        Object target = executionContextDataSource.getFunctionInstance();
+                        if (target == null) {
+                            target = this.containingClass.newInstance();
+                        }
+                        return target;
+                    });
             dataStore.setDataTargetValue(BindingDataStore.RETURN_NAME, retValue);
         } finally {
             Thread.currentThread().setContextClassLoader(ClassLoader.getSystemClassLoader());
         }
     }
 
+    @Override
+    public Class<?> getContainingClass() {
+        return containingClass;
+    }
+
+    @Override
+    public ClassLoader getClassLoader() {
+        return classLoader;
+    }
+
     private Class<?> getContainingClass(String className) throws ClassNotFoundException {
         return Class.forName(className, false, this.classLoader);
     }

src/main/java/com/microsoft/azure/functions/worker/broker/JavaFunctionBroker.java

@@ -10,6 +10,7 @@
 import com.microsoft.azure.functions.middleware.FunctionWorkerMiddleware;
 import com.microsoft.azure.functions.rpc.messages.*;
 import com.microsoft.azure.functions.worker.Constants;
+import com.microsoft.azure.functions.worker.WorkerLogManager;
 import com.microsoft.azure.functions.worker.binding.BindingDataStore;
 import com.microsoft.azure.functions.worker.binding.ExecutionContextDataSource;
 import com.microsoft.azure.functions.worker.binding.ExecutionRetryContext;
@@ -80,7 +81,7 @@ public Optional<TypedData> invokeMethod(String id, InvocationRequest request, Li
 		dataStore.addParameterSources(request.getInputDataList());
 		ExecutionTraceContext traceContext = new ExecutionTraceContext(request.getTraceContext().getTraceParent(), request.getTraceContext().getTraceState(), request.getTraceContext().getAttributesMap());
 		ExecutionRetryContext retryContext = new ExecutionRetryContext(request.getRetryContext().getRetryCount(), request.getRetryContext().getMaxRetryCount(), request.getRetryContext().getException());
-		ExecutionContextDataSource executionContextDataSource = new ExecutionContextDataSource(request.getInvocationId(), methodEntry.left, traceContext, retryContext);
+		ExecutionContextDataSource executionContextDataSource = new ExecutionContextDataSource(executor, request.getInvocationId(), methodEntry.left, traceContext, retryContext);
 		dataStore.addExecutionContextSource(executionContextDataSource);
 		executionContextDataSource.setDataStore(dataStore);
 		this.invocationChainBuilder.build(executor).doNext(executionContextDataSource);

src/main/java/com/microsoft/azure/functions/worker/broker/JavaMethodExecutor.java

@@ -15,4 +15,8 @@ public interface JavaMethodExecutor {
     ParameterResolver getOverloadResolver();
 
     void execute(ExecutionContextDataSource executionContextDataSource) throws Exception;
+
+    Class<?> getContainingClass();
+
+    ClassLoader getClassLoader();
 }

src/main/java/com/microsoft/azure/functions/worker/chain/FunctionExecutionMiddleware.java

@@ -3,6 +3,7 @@
 import com.microsoft.azure.functions.ExecutionContext;
 import com.microsoft.azure.functions.middleware.FunctionWorkerChain;
 import com.microsoft.azure.functions.middleware.FunctionWorkerMiddleware;
+import com.microsoft.azure.functions.middleware.MiddlewareExecutionContext;
 import com.microsoft.azure.functions.worker.binding.ExecutionContextDataSource;
 import com.microsoft.azure.functions.worker.broker.JavaMethodExecutor;
 import org.apache.commons.lang3.exception.ExceptionUtils;
@@ -16,7 +17,7 @@ public FunctionExecutionMiddleware(JavaMethodExecutor functionExecutor) {
     }
 
     @Override
-    public void invoke(ExecutionContext context, FunctionWorkerChain next) throws Exception{
+    public void invoke(MiddlewareExecutionContext context, FunctionWorkerChain next) throws Exception{
             this.functionExecutor.execute((ExecutionContextDataSource) context);
     }
 }

src/main/java/com/microsoft/azure/functions/worker/chain/InvocationChain.java

@@ -1,8 +1,8 @@
 package com.microsoft.azure.functions.worker.chain;
 
-import com.microsoft.azure.functions.ExecutionContext;
 import com.microsoft.azure.functions.middleware.FunctionWorkerChain;
 import com.microsoft.azure.functions.middleware.FunctionWorkerMiddleware;
+import com.microsoft.azure.functions.middleware.MiddlewareExecutionContext;
 import com.microsoft.azure.functions.worker.broker.JavaMethodExecutor;
 
 import java.util.ArrayList;
@@ -18,7 +18,7 @@ public InvocationChain(List<FunctionWorkerMiddleware> middlewareList) {
     }
 
     @Override
-    public void doNext(ExecutionContext context) throws Exception{
+    public void doNext(MiddlewareExecutionContext context) throws Exception{
         while (middlewareIterator.hasNext()) {
             middlewareIterator.next().invoke(context, this);
         }