Examples with Multiplexer io.quarkiverse.githubaction.runtime.Multiplexer used on opensource projects

Example 1 with Multiplexer

use of io.quarkiverse.githubaction.runtime.Multiplexer in project quarkus-github-action by quarkiverse.

the class GitHubActionProcessor method generateMultiplexers.

/**
 * Multiplexers listen to the sync events emitted by the main class.
 * <p>
 * They are subclasses of the application classes registering actions or listening to GitHub events through our annotations.
 * <p>
 * They are useful for several purposes:
 * <ul>
 * <li>A single application method can listen to multiple event types: the event types are qualifiers and CDI wouldn't allow
 * that (only events matching all the qualifiers would be received by the application method). That's why this class is
 * called a multiplexer: it will generate one method per event type and each generated method will delegate to the original
 * method.</li>
 * <li>The multiplexer also handles the resolution of payloads, config files...</li>
 * <li>We can inject a properly configured instance of GitHub or DynamicGraphQLClient into the method.</li>
 * </ul>
 */
private static void generateMultiplexers(ClassOutput beanClassOutput, DispatchingConfiguration dispatchingConfiguration, BuildProducer<ReflectiveClassBuildItem> reflectiveClasses) {
    for (Entry<DotName, TreeSet<ActionDispatchingMethod>> actionDispatchingMethodsEntry : dispatchingConfiguration.getMethods().entrySet()) {
        DotName declaringClassName = actionDispatchingMethodsEntry.getKey();
        TreeSet<ActionDispatchingMethod> actionDispatchingMethods = actionDispatchingMethodsEntry.getValue();
        ClassInfo declaringClass = actionDispatchingMethods.iterator().next().getMethod().declaringClass();
        reflectiveClasses.produce(new ReflectiveClassBuildItem(true, true, declaringClassName.toString()));
        String multiplexerClassName = declaringClassName + "_Multiplexer";
        reflectiveClasses.produce(new ReflectiveClassBuildItem(true, true, multiplexerClassName));
        ClassCreator multiplexerClassCreator = ClassCreator.builder().classOutput(beanClassOutput).className(multiplexerClassName).superClass(declaringClassName.toString()).build();
        multiplexerClassCreator.addAnnotation(Multiplexer.class);
        if (!BuiltinScope.isDeclaredOn(declaringClass)) {
            multiplexerClassCreator.addAnnotation(Singleton.class);
        }
        for (AnnotationInstance classAnnotation : declaringClass.classAnnotations()) {
            multiplexerClassCreator.addAnnotation(classAnnotation);
        }
        // Copy the constructors
        for (MethodInfo originalConstructor : declaringClass.constructors()) {
            MethodCreator constructorCreator = multiplexerClassCreator.getMethodCreator(MethodDescriptor.ofConstructor(multiplexerClassName, originalConstructor.parameters().stream().map(t -> t.name().toString()).toArray(String[]::new)));
            List<AnnotationInstance> originalMethodAnnotations = originalConstructor.annotations().stream().filter(ai -> ai.target().kind() == Kind.METHOD).collect(Collectors.toList());
            for (AnnotationInstance originalMethodAnnotation : originalMethodAnnotations) {
                constructorCreator.addAnnotation(originalMethodAnnotation);
            }
            Map<Short, List<AnnotationInstance>> originalConstructorParameterAnnotationMapping = originalConstructor.annotations().stream().filter(ai -> ai.target().kind() == Kind.METHOD_PARAMETER).collect(Collectors.groupingBy(ai -> ai.target().asMethodParameter().position()));
            List<ResultHandle> parametersRh = new ArrayList<>();
            for (short i = 0; i < originalConstructor.parameters().size(); i++) {
                parametersRh.add(constructorCreator.getMethodParam(i));
                AnnotatedElement parameterAnnotations = constructorCreator.getParameterAnnotations(i);
                List<AnnotationInstance> originalConstructorParameterAnnotations = originalConstructorParameterAnnotationMapping.getOrDefault(i, Collections.emptyList());
                for (AnnotationInstance originalConstructorParameterAnnotation : originalConstructorParameterAnnotations) {
                    parameterAnnotations.addAnnotation(originalConstructorParameterAnnotation);
                }
            }
            constructorCreator.invokeSpecialMethod(MethodDescriptor.of(originalConstructor), constructorCreator.getThis(), parametersRh.toArray(ResultHandle[]::new));
            constructorCreator.returnValue(null);
        }
        // Generate the multiplexed event dispatching methods
        for (ActionDispatchingMethod actionDispatchingMethod : actionDispatchingMethods) {
            String name = actionDispatchingMethod.getName();
            AnnotationInstance eventSubscriberInstance = actionDispatchingMethod.getEventSubscriberInstance();
            MethodInfo originalMethod = actionDispatchingMethod.getMethod();
            Map<Short, List<AnnotationInstance>> originalMethodParameterAnnotationMapping = originalMethod.annotations().stream().filter(ai -> ai.target().kind() == Kind.METHOD_PARAMETER).collect(Collectors.groupingBy(ai -> ai.target().asMethodParameter().position()));
            // if the method already has an @Observes or @ObservesAsync annotation
            if (originalMethod.hasAnnotation(DotNames.OBSERVES) || originalMethod.hasAnnotation(DotNames.OBSERVES_ASYNC)) {
                LOG.warn("Methods listening to GitHub actions may not be annotated with @Observes or @ObservesAsync. Offending method: " + originalMethod.declaringClass().name() + "#" + originalMethod);
            }
            List<String> parameterTypes = new ArrayList<>();
            List<Type> originalMethodParameterTypes = originalMethod.parameters();
            // detect the parameter that is a payload
            short payloadParameterPosition = -1;
            if (eventSubscriberInstance != null) {
                for (short i = 0; i < originalMethodParameterTypes.size(); i++) {
                    List<AnnotationInstance> parameterAnnotations = originalMethodParameterAnnotationMapping.getOrDefault(i, Collections.emptyList());
                    if (parameterAnnotations.stream().anyMatch(ai -> ai.name().equals(eventSubscriberInstance.name()))) {
                        payloadParameterPosition = i;
                        break;
                    }
                }
            }
            short j = 0;
            Map<Short, Short> parameterMapping = new HashMap<>();
            for (short i = 0; i < originalMethodParameterTypes.size(); i++) {
                List<AnnotationInstance> originalMethodAnnotations = originalMethodParameterAnnotationMapping.getOrDefault(i, Collections.emptyList());
                if (originalMethodAnnotations.stream().anyMatch(ai -> CONFIG_FILE.equals(ai.name())) || INJECTABLE_TYPES.contains(originalMethodParameterTypes.get(i).name()) || i == payloadParameterPosition) {
                    // if the parameter is annotated with @ConfigFile, is of an injectable type or is the payload, we skip it
                    continue;
                }
                parameterTypes.add(originalMethodParameterTypes.get(i).name().toString());
                parameterMapping.put(i, j);
                j++;
            }
            int configFileReaderParameterPosition = -1;
            if (originalMethod.hasAnnotation(CONFIG_FILE)) {
                parameterTypes.add(ConfigFileReader.class.getName());
                configFileReaderParameterPosition = j;
                j++;
            }
            parameterTypes.add(GitHubEvent.class.getName());
            int gitHubEventParameterPosition = j;
            MethodCreator methodCreator = multiplexerClassCreator.getMethodCreator(originalMethod.name() + "_" + HashUtil.sha1(originalMethod.toString() + "_" + (eventSubscriberInstance != null ? eventSubscriberInstance.toString() : EventDefinition.ALL)), originalMethod.returnType().name().toString(), parameterTypes.toArray());
            for (Type exceptionType : originalMethod.exceptions()) {
                methodCreator.addException(exceptionType.name().toString());
            }
            ResultHandle[] parameterValues = new ResultHandle[originalMethod.parameters().size()];
            // copy annotations except for @ConfigFile
            for (short i = 0; i < originalMethodParameterTypes.size(); i++) {
                List<AnnotationInstance> parameterAnnotations = originalMethodParameterAnnotationMapping.getOrDefault(i, Collections.emptyList());
                if (parameterAnnotations.isEmpty()) {
                    continue;
                }
                // Elements that are not in the mapping are ignored
                Short generatedParameterIndex = parameterMapping.get(i);
                if (generatedParameterIndex == null) {
                    continue;
                }
                AnnotatedElement generatedParameterAnnotations = methodCreator.getParameterAnnotations(generatedParameterIndex);
                for (AnnotationInstance annotationInstance : parameterAnnotations) {
                    generatedParameterAnnotations.addAnnotation(annotationInstance);
                }
            }
            // add annotations to the GitHubEvent parameter
            AnnotatedElement gitHubEventParameterAnnotations = methodCreator.getParameterAnnotations(gitHubEventParameterPosition);
            gitHubEventParameterAnnotations.addAnnotation(DotNames.OBSERVES.toString());
            gitHubEventParameterAnnotations.addAnnotation(Action.class).addValue("value", name);
            if (eventSubscriberInstance != null) {
                gitHubEventParameterAnnotations.addAnnotation(eventSubscriberInstance);
            }
            ResultHandle gitHubEventRh = methodCreator.getMethodParam(gitHubEventParameterPosition);
            // generate the code of the method
            for (short originalMethodParameterIndex = 0; originalMethodParameterIndex < originalMethodParameterTypes.size(); originalMethodParameterIndex++) {
                List<AnnotationInstance> parameterAnnotations = originalMethodParameterAnnotationMapping.getOrDefault(originalMethodParameterIndex, Collections.emptyList());
                Short multiplexerMethodParameterIndex = parameterMapping.get(originalMethodParameterIndex);
                if (originalMethodParameterIndex == payloadParameterPosition) {
                    parameterValues[originalMethodParameterIndex] = methodCreator.invokeVirtualMethod(MethodDescriptor.ofMethod(GitHubEvent.class, "getPayload", GHEventPayload.class), gitHubEventRh);
                } else if (INJECTABLE_TYPES.contains(originalMethodParameterTypes.get(originalMethodParameterIndex).name())) {
                    DotName injectableType = originalMethodParameterTypes.get(originalMethodParameterIndex).name();
                    parameterValues[originalMethodParameterIndex] = methodCreator.invokeVirtualMethod(MethodDescriptor.ofMethod(GitHubEvent.class, "get" + injectableType.withoutPackagePrefix(), injectableType.toString()), gitHubEventRh);
                } else if (parameterAnnotations.stream().anyMatch(ai -> ai.name().equals(CONFIG_FILE))) {
                    AnnotationInstance configFileAnnotationInstance = parameterAnnotations.stream().filter(ai -> ai.name().equals(CONFIG_FILE)).findFirst().get();
                    String configObjectType = originalMethodParameterTypes.get(originalMethodParameterIndex).name().toString();
                    boolean isOptional = false;
                    if (Optional.class.getName().equals(configObjectType)) {
                        if (originalMethodParameterTypes.get(originalMethodParameterIndex).kind() != Type.Kind.PARAMETERIZED_TYPE) {
                            throw new IllegalStateException("Optional is used but not parameterized for method " + originalMethod.declaringClass().name() + "#" + originalMethod);
                        }
                        isOptional = true;
                        configObjectType = originalMethodParameterTypes.get(originalMethodParameterIndex).asParameterizedType().arguments().get(0).name().toString();
                    }
                    ResultHandle gitHubRh = methodCreator.invokeVirtualMethod(MethodDescriptor.ofMethod(GitHubEvent.class, "getGitHub", GitHub.class), gitHubEventRh);
                    ResultHandle contextRh = methodCreator.invokeVirtualMethod(MethodDescriptor.ofMethod(GitHubEvent.class, "getContext", Context.class), gitHubEventRh);
                    ResultHandle repositoryRh = methodCreator.invokeInterfaceMethod(MethodDescriptor.ofMethod(Context.class, "getGitHubRepository", String.class), contextRh);
                    ResultHandle configFileReaderRh = methodCreator.getMethodParam(configFileReaderParameterPosition);
                    ResultHandle configObject = methodCreator.invokeVirtualMethod(MethodDescriptor.ofMethod(ConfigFileReader.class, "getConfigObject", Object.class, GitHub.class, String.class, String.class, Class.class), configFileReaderRh, gitHubRh, repositoryRh, methodCreator.load(configFileAnnotationInstance.value().asString()), methodCreator.loadClass(configObjectType));
                    configObject = methodCreator.checkCast(configObject, configObjectType);
                    if (isOptional) {
                        configObject = methodCreator.invokeStaticMethod(MethodDescriptor.ofMethod(Optional.class, "ofNullable", Optional.class, Object.class), configObject);
                    }
                    parameterValues[originalMethodParameterIndex] = configObject;
                } else {
                    parameterValues[originalMethodParameterIndex] = methodCreator.getMethodParam(multiplexerMethodParameterIndex);
                }
            }
            ResultHandle returnValue = methodCreator.invokeVirtualMethod(originalMethod, methodCreator.getThis(), parameterValues);
            methodCreator.returnValue(returnValue);
        }
        multiplexerClassCreator.close();
    }
}