I have already followed the guide here. I have tried both the config and "in code" approach of initializing and registering our telemetry processor. My goal is to filter out some HTTP responses so that those don't make their way to the sampled data. I haven't had any success. While our processor is initialized on app start, the Process method is never hit. Also, I already made sure that there is an InstrumentationKey in the config and that I'm using the correct key. What else am I missing?
This is what I have:
public class MyTelemetryProcessor : ITelemetryProcessor
{
private ITelemetryProcessor Next { get; set; }
// You can pass values from .config
public string MyParamFromConfigFile { get; set; }
// Link processors to each other in a chain.
public MyTelemetryProcessor(ITelemetryProcessor next)
{
this.Next = next; <-- this is always hit indicating this processor is active
}
public void Process(ITelemetry item)
{
// To filter out an item, just return
if (!OKtoSend(item)) { return; } <-- breakpoint here is never hit
// Modify the item if required
ModifyItem(item);
this.Next.Process(item);
}
private bool OKtoSend(ITelemetry item) <-- and consequently this method is never hit
{
var request = item as RequestTelemetry; <-- breakpoint here is never hit
// some more code goes here
return request.Success.GetValueOrDefault(false);
}
// Example: replace with your own modifiers.
private void ModifyItem(ITelemetry item)
{
item.Context.Properties.Add("app-version", "1." + MyParamFromConfigFile);
}
}
And this is how it is registered. I can see this being hit during debugging when the app starts up:
var builder = TelemetryConfiguration.Active.TelemetryProcessorChainBuilder;
builder.Use((next) => new MyTelemetryProcessor (next));
builder.Build();
In aspnetcore, my solution was to use :
services.AddApplicationInsightsTelemetryProcessor(typeof(BasicTelemetryFilter));
(using the regular CreateWebHostBuilder :
WebHost.CreateDefaultBuilder(args)
.UseApplicationInsights()
.UseStartup<Startup>();
)
Like to understand how onStarted() is being called. Does kaaClient.start() executed onStarted()? I tried to debug with ecplise and found it always executed "sleepForSeconds(MAX_SECONDS_TO_INIT_KAA);" before going to "LOG.info("--= Kaa client started =--")" but I can't tell when onStarted() was executed.
public static void main(String[] args) {
LOG.info("--= Data collection demo started =--");
/*
* Create a Kaa client with the Kaa desktop context.
*/
KaaClient kaaClient = Kaa.newClient(new DesktopKaaPlatformContext(), new SimpleKaaClientStateListener() {
#Override
public void onStarted() {
LOG.info("--= Kaa client started =--");
}
#Override
public void onStopped() {
LOG.info("--= Kaa client stopped =--");
}
}, true);
/*
* Set record count strategy for uploading every log record as soon as it is created.
*/
kaaClient.setLogUploadStrategy(new RecordCountLogUploadStrategy(LOGS_DEFAULT_THRESHOLD));
/*
* Displays endpoint's configuration and change sampling period each time configuration will be updated.
*/
kaaClient.addConfigurationListener(new ConfigurationListener() {
#Override
public void onConfigurationUpdate(Configuration configuration) {
LOG.info("--= Endpoint configuration was updated =--");
displayConfiguration(configuration);
Integer newSamplePeriod = configuration.getSamplePeriod();
if ((newSamplePeriod != null) && (newSamplePeriod > 0)) {
changeMeasurementPeriod(kaaClient, newSamplePeriod);
} else {
LOG.warn("Sample period value (= {}) in updated configuration is wrong, so ignore it.", newSamplePeriod);
}
}
});
/*
* Start the Kaa client and connect it to the Kaa server.
*/
kaaClient.start();
sleepForSeconds(MAX_SECONDS_TO_INIT_KAA);
/*
* Start periodical temperature value generating and sending results to Kaa node
*/
startMeasurement(kaaClient);
LOG.info("*** Press Enter to stop sending log records ***");
waitForAnyInput();
/*
* Stop generating and sending data to Kaa node
*/
stopMeasurement();
/*
* Stop the Kaa client and release all the resources which were in use.
*/
kaaClient.stop();
displayResults();
LOG.info("--= Data collection demo stopped =--");
}
Method onStarted() called in the start() method. For details see AbstaractKaaClient.
We have rest api application. We use redis for API response caching and internal method caching. If redis connection then it is making our API down. We want to bypass the redis caching if that redis connection fails or any exception instead of making our API down.
There is a interface CacheErrorHandler but it handles the redis get set operation failures not redis connection problems. We are using Spring 4.1.2.
Let's boil this down a bit. Your application uses caching (implemented with Redis). If the Redis connection is stale/closed or otherwise, then you want the application to bypass caching and (presumably) go directly to an underlying data store (e.g. RDBMS). The application Service logic might look similar to...
#Service
class CustomerService ... {
#Autowired
private CustomerRepository customerRepo;
protected CustomerRepository getCustomerRepo() {
Assert.notNull(customerRepo, "The CustomerRepository was not initialized!");
return customerRepo;
}
#Cacheable(value = "Customers")
public Customer getCustomer(Long customerId) {
return getCustomerRepo().load(customerId);
}
...
}
All that matters in Spring core's Caching Abstraction to ascertain a Cache "miss" is that the value returned is null. As such, Spring Caching Infrastructure will then proceed in calling the actual Service method (i.e. getCustomer). Keep in mind on the return of the getCustomerRepo().load(customerId) call, you also need to handle the case where Spring's Caching Infrastructure attempts to now cache the value.
In the spirit of keeping it simple, we will do without AOP, but you should be able to achieve this using AOP as well (your choice).
All you (should) need is a "custom" RedisCacheManager extending the SDR CacheManager implementation, something like...
package example;
import org.springframework.cache.Cache;
import org.springframework.data.redis.cache.RedisCacheManager;
...
class MyCustomRedisCacheManager extends RedisCacheManager {
public MyCustomerRedisCacheManager(RedisTemplate redisTemplate) {
super(redisTemplate);
}
#Override
public Cache getCache(String name) {
return new RedisCacheWrapper(super.getCache(name));
}
protected static class RedisCacheWrapper implements Cache {
private final Cache delegate;
public RedisCacheWrapper(Cache redisCache) {
Assert.notNull(redisCache, "'delegate' must not be null");
this.delegate = redisCache;
}
#Override
public Cache.ValueWrapper get(Object key) {
try {
delegate.get(key);
}
catch (Exception e) {
return handleErrors(e);
}
}
#Override
public void put(Object key, Object value) {
try {
delegate.put(key, value);
}
catch (Exception e) {
handleErrors(e);
}
}
// implement clear(), evict(key), get(key, type), getName(), getNativeCache(), putIfAbsent(key, value) accordingly (delegating to the delegate).
protected <T> T handleErrors(Exception e) throws Exception {
if (e instanceof <some RedisConnection Exception type>) {
// log the connection problem
return null;
}
else if (<something different>) { // act appropriately }
...
else {
throw e;
}
}
}
}
So, if Redis is unavailable, perhaps the best you can do is log the problem and proceed to let the Service invocation happen. Clearly, this will hamper performance but at least it will raise awareness that a problem exists. Clearly, this could be tied into a more robust notification system, but it is a crude example of the possibilities. The important thing is, your Service remains available while the other services (e.g. Redis) that the application service depends on, may have failed.
In this implementation (vs. my previous explanation) I chose to delegate to the underlying, actual RedisCache implementation to let the Exception occur, then knowing full well a problem with Redis exists, and so that you can deal with the Exception appropriately. However, if you are a certain that the Exception is related to a connection problem upon inspection, you can return "null" to let Spring Caching Infrastructure proceed as if it were a Cache "miss" (i.e. bad Redis Connection == Cache miss, in this case).
I know something like this should help your problem as I built a similar prototype of a "custom" CacheManager implementation for GemFire and one of Pivotal's customers. In that particular UC, the Cache "miss" had to be triggered by an "out-of-date version" of the application domain object where production had a mix of newer and older application clients connecting to GemFire through Spring's Caching Abstraction. The application domain object fields would change in newer versions of the app for instance.
Anyway, hope this helps or gives you more ideas.
Cheers!
So, I was digging through the core Spring Framework Caching Abstraction source today addressing another question and it seems if a CacheErrorHandler is implemented properly, then perhaps a problematic Redis Connection could still result in the desired behavior, e.g. cache "miss" (triggered with the return of a null value).
See the AbstractCacheInvoker source for more details.
The cache.get(key) should result in an exception due to a faulty Redis Connection and thus Exception handler would be invoked...
catch (RuntimeException e) {
getErrorHandler().handleCacheGetError(e, cache, key);
return null; // If the exception is handled, return a cache miss
}
If the CacheErrorHandler properly handles the Cache "get" error (and does not re-throw the/an Exception), then a null value will be returned indicating a cache "miss".
Thank you #John Blum. My solution in Spring Boot is as follows.
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cache.Cache;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.core.RedisOperations;
import org.springframework.util.Assert;
import java.util.concurrent.Callable;
class CustomRedisCacheManager extends RedisCacheManager {
private static Logger logger = LoggerFactory.getLogger(CustomRedisCacheManager.class);
public CustomRedisCacheManager(RedisOperations redisOperations) {
super(redisOperations);
}
#Override
public Cache getCache(String name) {
return new RedisCacheWrapper(super.getCache(name));
}
protected static class RedisCacheWrapper implements Cache {
private final Cache delegate;
public RedisCacheWrapper(Cache redisCache) {
Assert.notNull(redisCache, "delegate cache must not be null");
this.delegate = redisCache;
}
#Override
public String getName() {
try {
return delegate.getName();
} catch (Exception e) {
return handleException(e);
}
}
#Override
public Object getNativeCache() {
try {
return delegate.getNativeCache();
} catch (Exception e) {
return handleException(e);
}
}
#Override
public Cache.ValueWrapper get(Object key) {
try {
return delegate.get(key);
} catch (Exception e) {
return handleException(e);
}
}
#Override
public <T> T get(Object o, Class<T> aClass) {
try {
return delegate.get(o, aClass);
} catch (Exception e) {
return handleException(e);
}
}
#Override
public <T> T get(Object o, Callable<T> callable) {
try {
return delegate.get(o, callable);
} catch (Exception e) {
return handleException(e);
}
}
#Override
public void put(Object key, Object value) {
try {
delegate.put(key, value);
} catch (Exception e) {
handleException(e);
}
}
#Override
public ValueWrapper putIfAbsent(Object o, Object o1) {
try {
return delegate.putIfAbsent(o, o1);
} catch (Exception e) {
return handleException(e);
}
}
#Override
public void evict(Object o) {
try {
delegate.evict(o);
} catch (Exception e) {
handleException(e);
}
}
#Override
public void clear() {
try {
delegate.clear();
} catch (Exception e) {
handleException(e);
}
}
private <T> T handleException(Exception e) {
logger.error("handleException", e);
return null;
}
}
}
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.core.RedisTemplate;
#Configuration
public class RedisConfig {
#Bean
public RedisCacheManager redisCacheManager(RedisTemplate redisTemplate) {
CustomRedisCacheManager redisCacheManager = new CustomRedisCacheManager(redisTemplate);
redisCacheManager.setUsePrefix(true);
return redisCacheManager;
}
}
actually my response is directed to Mr. #Vivek Aditya - I faced the same problem: new spring-data-redis api and not constructing RedisCacheManager per RedisTemplate. The only option - based on #John Blum suggestions - was to use aspects. And below is my code.
#Aspect
#Component
public class FailoverRedisCacheAspect {
private static class FailoverRedisCache extends RedisCache {
protected FailoverRedisCache(RedisCache redisCache) {
super(redisCache.getName(), redisCache.getNativeCache(), redisCache.getCacheConfiguration());
}
#Override
public <T> T get(Object key, Callable<T> valueLoader) {
try {
return super.get(key, valueLoader);
} catch (RuntimeException ex) {
return valueFromLoader(key, valueLoader);
}
}
private <T> T valueFromLoader(Object key, Callable<T> valueLoader) {
try {
return valueLoader.call();
} catch (Exception e) {
throw new ValueRetrievalException(key, valueLoader, e);
}
}
}
#Around("execution(* org.springframework.cache.support.AbstractCacheManager.getCache (..))")
public Cache beforeSampleCreation(ProceedingJoinPoint proceedingJoinPoint) {
try {
Cache cache = (Cache) proceedingJoinPoint.proceed(proceedingJoinPoint.getArgs());
if (cache instanceof RedisCache) {
return new FailoverRedisCache((RedisCache) cache);
} else {
return cache;
}
} catch (Throwable ex) {
return null;
}
}
}
works fine for all reasonable scenarios:
app starts fine with redis down
app (still) works during (sudden) redis outage
when redis starts working again, app sees it
Edit: the code is more like a poc - only for "get", and I don't like reinstantiating FailoverRedisCache every single cache hit - there should be a map.
None of the above worked for us when using Spring Boot 2.3.9.release with Redis. We ended up creating and registering our own customized CacheErrorHandler named CustomCacheErrorHandler to override the default SimpleCacheErrorHandler provided by Spring Framework. This will work perfectly.
#Configuration
public class CachingConfiguration extends CachingConfigurerSupport {
#Override
public CacheErrorHandler errorHandler() {
return new CustomCacheErrorHandler();
}
}
class CustomCacheErrorHandler implements CacheErrorHandler {
Logger log = Logger.get(CustomCacheErrorHandler.class);
#Override
public void handleCacheGetError(RuntimeException e, Cache cache, Object o) {
log.error(e.getMessage(), e);
}
#Override
public void handleCachePutError(RuntimeException e, Cache cache, Object o, Object o1) {
log.error(e.getMessage(), e);
}
#Override
public void handleCacheEvictError(RuntimeException e, Cache cache, Object o) {
log.error(e.getMessage(), e);
}
#Override
public void handleCacheClearError(RuntimeException e, Cache cache) {
log.error(e.getMessage(), e);
}
}
I had same problem, but, unfortunately, none of the above solutions work for me. I checked for the problem and found out that the executed command never timed out if there was no connection to Redis. So I start to study lettuce library for a solution. I solve the problem by rejecting the command when there is no connection:
#Bean
public LettuceConnectionFactory lettuceConnectionFactory()
{
final SocketOptions socketOptions = SocketOptions.builder().connectTimeout(Duration.ofSeconds(10)).build();
ClientOptions clientOptions = ClientOptions.builder()
.socketOptions(socketOptions)
.autoReconnect(true)
.disconnectedBehavior(ClientOptions.DisconnectedBehavior.REJECT_COMMANDS)
.build();
LettuceClientConfiguration clientConfig = LettuceClientConfiguration.builder()
.commandTimeout(Duration.ofSeconds(10))
.clientOptions(clientOptions).build();
RedisStandaloneConfiguration redisStandaloneConfiguration = new RedisStandaloneConfiguration(this.host, this.port);
return new LettuceConnectionFactory(redisStandaloneConfiguration, clientConfig);
}
All the core Spring Framework Cache abstraction annotations (e.g. #Cacheable) along with the JSR-107 JCache annotations supported by the core SF delegate to the underlying CacheManager under-the-hood, and for Redis, that is the RedisCacheManager.
You would configure the RedisCacheManager in Spring XML configuration meta-data similar to here.
One approach would be to write an AOP Proxy for the (Redis)CacheManager that uses the RedisConnection (indirectly from the RedisTemplate) to ascertain the state of the connection on each (Redis)CacheManger operation.
If the connection has failed, or is closed, for standard cache ops, the (Redis)CacheManager could return an instance of RedisCache for getCache(String name) that always returns null (indicating a Cache miss on an entry), thus passing through to the underlying data store.
There maybe better ways to handle this as I am not an expert on all things Redis (or SDR), but this should work and perhaps give you a few ides of your own.
Cheers.
You can use CacheErrorHandler. But you should make sure to make
RedisCacheManager transactionAware to false in your Redis Cache Config(to make sure the transaction is committed early when executing the caching part and the error is caught by CacheErrorHandler and don't wait until the end of the execution which skips CacheErrorHandler part). The function to set transactionAware to false looks like this:
#Bean
public RedisCacheManager redisCacheManager(LettuceConnectionFactory lettuceConnectionFactory) {
JdkSerializationRedisSerializer redisSerializer = new JdkSerializationRedisSerializer(getClass().getClassLoader());
RedisCacheConfiguration redisCacheConfiguration = RedisCacheConfiguration.defaultCacheConfig()
.entryTtl(Duration.ofHours(redisDataTTL))
.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer));
redisCacheConfiguration.usePrefix();
RedisCacheManager redisCacheManager = RedisCacheManager.RedisCacheManagerBuilder.fromConnectionFactory(lettuceConnectionFactory)
.cacheDefaults(redisCacheConfiguration)
.build();
redisCacheManager.setTransactionAware(false);
return redisCacheManager;
}
I'm face a problem since few days and I can't get solution. below is my app structure:
I have ejbapp.jar inside MyearDeployedOnJboss7.ear at the same level of equinox-server-side-app.war (built using warproduct) and I want to load class from MyJarToLaoadForEjbapp.jar which is in iModernizeWebClient_1.0.0.jar which is in plugins folder of equinox-server-side-app.war (I want show image of app structure but I cannot send image because forum rules need 10 score to be able to do that)
My question is how to allow ejbapp.jar load classes from "MyJarToLaoadForEjbapp.jar" inside MyWebClient_1.0.0.jar's plugin folder which is in the equinox-server-side-app.war.
I think using servletbridge classloader but no idea how to use it.
in my launch.ini I've:
osgi.*=#null org.osgi.*=#null eclipse.*=#null osgi.parentClassloader=app osgi.contextClassLoaderParent=app
I resolved my proble using Servlet HttpServiceTracker from the OSGI spec. how to do it : write HttpServiceTracker liket that :
public class HttpServiceTracker extends ServiceTracker {
private static final Logger logger = Logger
.getLogger(HttpServiceTracker.class.getName());
public HttpServiceTracker(BundleContext context) {
super(context, HttpService.class.getName(), null);
}
public Object addingService(ServiceReference reference) {
HttpService httpService = (HttpService) context.getService(reference);
logger.info("default context path : "
+ org.eclipse.rap.ui.internal.servlet.HttpServiceTracker.ID_HTTP_CONTEXT);
try {
logger.info("will register servlet ");
httpService.registerServlet("/programLauncherServlet",
new ProgramLauncherServlet(), null, null);
logger.info("servlet has been registred with http context ");
// httpService.registerResources( "/", "/html", null );
} catch (Exception e) {
//e.printStackTrace();
logger.info("The alias '/programLauncherServlet' is already in use");
}
return httpService;
}
public void removedService(ServiceReference reference, Object service) {
logger.info("will unregister servlet ");
HttpService httpService = (HttpService) service;
httpService.unregister("/programLauncher");
super.removedService(reference, service);
logger.info("servlet has been unregistred");
}
in your plugin activator class at method start :
#Override
public void start(BundleContext context) throws Exception {
super.start(context);
Activator.plugin = this;
BundleContext osgiContext = BundleReference.class
.cast(AnyClassOfYourProject.class.getClassLoader()).getBundle()
.getBundleContext();
serviceTracker = new HttpServiceTracker(osgiContext);
serviceTracker.open();
LOGGER.info("servlet published !!");
LOGGER.info("Bundle started.");
}
and for unregister the servlet at the stop method :
public void stop(BundleContext context) throws Exception {
Activator.plugin = null;
serviceTracker.close();
serviceTracker = null;
LOGGER.info("servlet unregistered from context !!");
super.stop(context);
}
that's all. your servlet is accessible outside your eclipse bundle and you can call methods inside the bundle.
I'm starting a web application that contains the following projects:
Booking.Web
Booking.Services
Booking.DataObjects
Booking.Data
I'm using the repository pattern in my data project only. All services will be the same, no matter what happens. However, if a customer wants to use Access, it will use a different data repository than if the customer wants to use SQL Server.
I have StructureMap, and want to be able to do the following:
Web project is unaffected. It's a web forms application that will only know about the services project and the dataobjects project.
When a service is called, it will use StructureMap (by looking up the bootstrapper.cs file) to see which data repository to use.
An example of a services class is the error logging class:
public class ErrorLog : IErrorLog
{
ILogging logger;
public ErrorLog()
{
}
public ErrorLog(ILogging logger)
{
this.logger = logger;
}
public void AddToLog(string errorMessage)
{
try
{
AddToDatabaseLog(errorMessage);
}
catch (Exception ex)
{
AddToFileLog(ex.Message);
}
finally
{
AddToFileLog(errorMessage);
}
}
private void AddToDatabaseLog(string errorMessage)
{
ErrorObject error =
new ErrorObject
{
ErrorDateTime = DateTime.Now,
ErrorMessage = errorMessage
};
logger.Insert(error);
}
private void AddToFileLog(string errorMessage)
{
// TODO: Take this value from the web.config instead of hard coding it
TextWriter writer = new StreamWriter(#"E:\Work\Booking\Booking\Booking.Web\Logs\ErrorLog.txt", true);
writer.WriteLine(DateTime.Now.ToString() + " ---------- " + errorMessage);
writer.Close();
}
}
I want to be able to call this service from my web project, without defining which repository to use for the data access. My boostrapper.cs file in the services project is defined as:
public class Bootstrapper
{
public static void ConfigureStructureMap()
{
ObjectFactory.Initialize(x =>
{
x.AddRegistry(new ServiceRegistry());
}
);
}
public class ServiceRegistry : Registry
{
protected override void configure()
{
ForRequestedType<IErrorLog>().TheDefaultIsConcreteType<Booking.Services.Logging.ErrorLog>();
ForRequestedType<ILogging>().TheDefaultIsConcreteType<SqlServerLoggingProvider>();
}
}
}
What else do I need to get this to work? When I defined a test, the ILogger object was null.
Perhaps some details on how you are calling this code from a test would be useful.
My understanding is that you need to ensure that the ConfigureStructureMap call has been made early in the applications life (e.g. in the Global.asax in a web project).
After that you would be calling for instances of IErrorLog using something like:
IErrorLog log = StructureMap.ObjectFactory.GetNamedInstance<IErrorLog>();