Examples with ReactiveClientResultTransformer io.micronaut.http.client.ReactiveClientResultTransformer used on opensource projects

Example 1 with ReactiveClientResultTransformer

use of io.micronaut.http.client.ReactiveClientResultTransformer in project micronaut-core by micronaut-projects.

the class HttpClientIntroductionAdvice method intercept.

/**
 * Interceptor to apply headers, cookies, parameter and body arguements.
 *
 * @param context The context
 * @return httpClient or future
 */
@Nullable
@Override
public Object intercept(MethodInvocationContext<Object, Object> context) {
    if (!context.hasStereotype(Client.class)) {
        throw new IllegalStateException("Client advice called from type that is not annotated with @Client: " + context);
    }
    final AnnotationMetadata annotationMetadata = context.getAnnotationMetadata();
    Class<?> declaringType = context.getDeclaringType();
    if (Closeable.class == declaringType || AutoCloseable.class == declaringType) {
        clientFactory.disposeClient(annotationMetadata);
        return null;
    }
    Optional<Class<? extends Annotation>> httpMethodMapping = context.getAnnotationTypeByStereotype(HttpMethodMapping.class);
    HttpClient httpClient = clientFactory.getClient(annotationMetadata);
    if (context.hasStereotype(HttpMethodMapping.class) && httpClient != null) {
        AnnotationValue<HttpMethodMapping> mapping = context.getAnnotation(HttpMethodMapping.class);
        String uri = mapping.getRequiredValue(String.class);
        if (StringUtils.isEmpty(uri)) {
            uri = "/" + context.getMethodName();
        }
        Class<? extends Annotation> annotationType = httpMethodMapping.get();
        HttpMethod httpMethod = HttpMethod.parse(annotationType.getSimpleName().toUpperCase(Locale.ENGLISH));
        String httpMethodName = context.stringValue(CustomHttpMethod.class, "method").orElse(httpMethod.name());
        MutableHttpRequest<?> request = HttpRequest.create(httpMethod, "", httpMethodName);
        UriMatchTemplate uriTemplate = UriMatchTemplate.of("");
        if (!(uri.length() == 1 && uri.charAt(0) == '/')) {
            uriTemplate = uriTemplate.nest(uri);
        }
        Map<String, Object> pathParams = new HashMap<>();
        Map<String, List<String>> queryParams = new LinkedHashMap<>();
        ClientRequestUriContext uriContext = new ClientRequestUriContext(uriTemplate, pathParams, queryParams);
        List<Argument> bodyArguments = new ArrayList<>();
        List<String> uriVariables = uriTemplate.getVariableNames();
        Map<String, MutableArgumentValue<?>> parameters = context.getParameters();
        ClientArgumentRequestBinder<Object> defaultBinder = (ctx, uriCtx, value, req) -> {
            Argument<?> argument = ctx.getArgument();
            if (uriCtx.getUriTemplate().getVariableNames().contains(argument.getName())) {
                String name = argument.getAnnotationMetadata().stringValue(Bindable.class).orElse(argument.getName());
                // Convert and put as path param
                if (argument.getAnnotationMetadata().hasStereotype(Format.class)) {
                    ConversionService.SHARED.convert(value, ConversionContext.STRING.with(argument.getAnnotationMetadata())).ifPresent(v -> pathParams.put(name, v));
                } else {
                    pathParams.put(name, value);
                }
            } else {
                bodyArguments.add(ctx.getArgument());
            }
        };
        // Apply all the method binders
        List<Class<? extends Annotation>> methodBinderTypes = context.getAnnotationTypesByStereotype(Bindable.class);
        // @Version is not a bindable, so it needs to looked for separately
        methodBinderTypes.addAll(context.getAnnotationTypesByStereotype(Version.class));
        if (!CollectionUtils.isEmpty(methodBinderTypes)) {
            for (Class<? extends Annotation> binderType : methodBinderTypes) {
                binderRegistry.findAnnotatedBinder(binderType).ifPresent(b -> b.bind(context, uriContext, request));
            }
        }
        InterceptedMethod interceptedMethod = InterceptedMethod.of(context);
        // Apply all the argument binders
        Argument[] arguments = context.getArguments();
        if (arguments.length > 0) {
            for (Argument argument : arguments) {
                Object definedValue = getValue(argument, context, parameters);
                if (definedValue != null) {
                    final ClientArgumentRequestBinder<Object> binder = (ClientArgumentRequestBinder<Object>) binderRegistry.findArgumentBinder((Argument<Object>) argument).orElse(defaultBinder);
                    ArgumentConversionContext conversionContext = ConversionContext.of(argument);
                    binder.bind(conversionContext, uriContext, definedValue, request);
                    if (conversionContext.hasErrors()) {
                        return interceptedMethod.handleException(new ConversionErrorException(argument, conversionContext.getLastError().get()));
                    }
                }
            }
        }
        Object body = request.getBody().orElse(null);
        if (body == null && !bodyArguments.isEmpty()) {
            Map<String, Object> bodyMap = new LinkedHashMap<>();
            for (Argument bodyArgument : bodyArguments) {
                String argumentName = bodyArgument.getName();
                MutableArgumentValue<?> value = parameters.get(argumentName);
                bodyMap.put(argumentName, value.getValue());
            }
            body = bodyMap;
            request.body(body);
        }
        boolean variableSatisfied = uriVariables.isEmpty() || pathParams.keySet().containsAll(uriVariables);
        if (body != null && !variableSatisfied) {
            if (body instanceof Map) {
                for (Map.Entry<Object, Object> entry : ((Map<Object, Object>) body).entrySet()) {
                    String k = entry.getKey().toString();
                    Object v = entry.getValue();
                    if (v != null) {
                        pathParams.putIfAbsent(k, v);
                    }
                }
            } else {
                BeanMap<Object> beanMap = BeanMap.of(body);
                for (Map.Entry<String, Object> entry : beanMap.entrySet()) {
                    String k = entry.getKey();
                    Object v = entry.getValue();
                    if (v != null) {
                        pathParams.putIfAbsent(k, v);
                    }
                }
            }
        }
        if (!HttpMethod.permitsRequestBody(httpMethod)) {
            // If a binder set the body and the method does not permit it, reset to null
            request.body(null);
            body = null;
        }
        uri = uriTemplate.expand(pathParams);
        // Remove all the pathParams that have already been used.
        // Other path parameters are added to query
        uriVariables.forEach(pathParams::remove);
        addParametersToQuery(pathParams, uriContext);
        // The original query can be added by getting it from the request.getUri() and appending
        request.uri(URI.create(appendQuery(uri, uriContext.getQueryParameters())));
        if (body != null && !request.getContentType().isPresent()) {
            MediaType[] contentTypes = MediaType.of(context.stringValues(Produces.class));
            if (ArrayUtils.isEmpty(contentTypes)) {
                contentTypes = DEFAULT_ACCEPT_TYPES;
            }
            if (ArrayUtils.isNotEmpty(contentTypes)) {
                request.contentType(contentTypes[0]);
            }
        }
        request.setAttribute(HttpAttributes.INVOCATION_CONTEXT, context);
        // Set the URI template used to make the request for tracing purposes
        request.setAttribute(HttpAttributes.URI_TEMPLATE, resolveTemplate(annotationMetadata, uriTemplate.toString()));
        String serviceId = getClientId(annotationMetadata);
        Argument<?> errorType = annotationMetadata.classValue(Client.class, "errorType").map((Function<Class, Argument>) Argument::of).orElse(HttpClient.DEFAULT_ERROR_TYPE);
        request.setAttribute(HttpAttributes.SERVICE_ID, serviceId);
        final MediaType[] acceptTypes;
        Collection<MediaType> accept = request.accept();
        if (accept.isEmpty()) {
            String[] consumesMediaType = context.stringValues(Consumes.class);
            if (ArrayUtils.isEmpty(consumesMediaType)) {
                acceptTypes = DEFAULT_ACCEPT_TYPES;
            } else {
                acceptTypes = MediaType.of(consumesMediaType);
            }
            request.accept(acceptTypes);
        } else {
            acceptTypes = accept.toArray(MediaType.EMPTY_ARRAY);
        }
        ReturnType<?> returnType = context.getReturnType();
        try {
            Argument<?> valueType = interceptedMethod.returnTypeValue();
            Class<?> reactiveValueType = valueType.getType();
            switch(interceptedMethod.resultType()) {
                case PUBLISHER:
                    boolean isSingle = returnType.isSingleResult() || returnType.isCompletable() || HttpResponse.class.isAssignableFrom(reactiveValueType) || HttpStatus.class == reactiveValueType;
                    Publisher<?> publisher;
                    if (!isSingle && httpClient instanceof StreamingHttpClient) {
                        publisher = httpClientResponseStreamingPublisher((StreamingHttpClient) httpClient, acceptTypes, request, errorType, valueType);
                    } else {
                        publisher = httpClientResponsePublisher(httpClient, request, returnType, errorType, valueType);
                    }
                    Object finalPublisher = interceptedMethod.handleResult(publisher);
                    for (ReactiveClientResultTransformer transformer : transformers) {
                        finalPublisher = transformer.transform(finalPublisher);
                    }
                    return finalPublisher;
                case COMPLETION_STAGE:
                    Publisher<?> csPublisher = httpClientResponsePublisher(httpClient, request, returnType, errorType, valueType);
                    CompletableFuture<Object> future = new CompletableFuture<>();
                    csPublisher.subscribe(new CompletionAwareSubscriber<Object>() {

                        AtomicReference<Object> reference = new AtomicReference<>();

                        @Override
                        protected void doOnSubscribe(Subscription subscription) {
                            subscription.request(1);
                        }

                        @Override
                        protected void doOnNext(Object message) {
                            if (Void.class != reactiveValueType) {
                                reference.set(message);
                            }
                        }

                        @Override
                        protected void doOnError(Throwable t) {
                            if (t instanceof HttpClientResponseException) {
                                HttpClientResponseException e = (HttpClientResponseException) t;
                                if (e.getStatus() == HttpStatus.NOT_FOUND) {
                                    if (reactiveValueType == Optional.class) {
                                        future.complete(Optional.empty());
                                    } else if (HttpResponse.class.isAssignableFrom(reactiveValueType)) {
                                        future.complete(e.getResponse());
                                    } else {
                                        future.complete(null);
                                    }
                                    return;
                                }
                            }
                            if (LOG.isErrorEnabled()) {
                                LOG.error("Client [" + declaringType.getName() + "] received HTTP error response: " + t.getMessage(), t);
                            }
                            future.completeExceptionally(t);
                        }

                        @Override
                        protected void doOnComplete() {
                            future.complete(reference.get());
                        }
                    });
                    return interceptedMethod.handleResult(future);
                case SYNCHRONOUS:
                    Class<?> javaReturnType = returnType.getType();
                    BlockingHttpClient blockingHttpClient = httpClient.toBlocking();
                    if (void.class == javaReturnType || httpMethod == HttpMethod.HEAD) {
                        request.getHeaders().remove(HttpHeaders.ACCEPT);
                    }
                    if (HttpResponse.class.isAssignableFrom(javaReturnType)) {
                        return handleBlockingCall(javaReturnType, () -> blockingHttpClient.exchange(request, returnType.asArgument().getFirstTypeVariable().orElse(Argument.OBJECT_ARGUMENT), errorType));
                    } else if (void.class == javaReturnType) {
                        return handleBlockingCall(javaReturnType, () -> blockingHttpClient.exchange(request, null, errorType));
                    } else {
                        return handleBlockingCall(javaReturnType, () -> blockingHttpClient.retrieve(request, returnType.asArgument(), errorType));
                    }
                default:
                    return interceptedMethod.unsupported();
            }
        } catch (Exception e) {
            return interceptedMethod.handleException(e);
        }
    }
    // try other introduction advice
    return context.proceed();
}