grpc-java: setting enableRetry and maxRetryAttempt is not Retrying - grpc

Grpc client is not retrying and failed with UNAVAILABLE: io exception. Currently I am setting the retry and maxRetryAttempt like below:
Channel channel = NettyChannelBuilder.forAddress(address.getTarget(), address.getPort())
.enableRetry()
.maxRetryAttempts(3)
.intercept(interceptors)
.sslContext(context.build())
.build();
Is enableRetry and maxRetryAttempt supported in io.grpc:grpc-netty:1.18.0?
Thanks.

Neither enableRetry() nor maxRetryAttempts() configures retry on a per-method basis. enableRetry() enabled the entire "subsystem," such that configuration will be followed; eventually it will be enabled by default, bu that wouldn't imply retries would happen for all methods. And maxRetryAttempts() limits the configuration; if the configuration says to do 5 and you set the limit to 3, then only 3 will be done. But it doesn't increase the number of retry attempts.
The "configuration" that I keep referring to comes from service config. See gRFC A6 Client Retries for the configuration keys. Service config itself is not currently enabled by default as well. For retries, the easiest way to try it out is to use ManagedChannelBuilder.defaultServiceConfig(Map serviceConfig) that was added to v1.20.0 (soon to be released). But you can also use TXT records in DNS and pass -Dio.grpc.internal.DnsNameResolverProvider.enable_service_config=true when executing your binary.
Retries and service config are currently both experimental.

Related

SocketTimeoutException when calling load for DynamoDBMapper

I am getting sometimes this error when calling load for DynamoDBMapper:
java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
at java.net.SocketInputStream.read(SocketInputStream.java:171)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
at java.io.BufferedInputStream.read1(BufferedInputStream.java:286)
at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:735)
at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:678)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1593)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1498)
at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:480)
at com.amazonaws.internal.EC2ResourceFetcher.doReadResource(EC2ResourceFetcher.java:82)
at com.amazonaws.internal.InstanceMetadataServiceResourceFetcher.getToken(InstanceMetadataServiceResourceFetcher.java:91)
at com.amazonaws.internal.InstanceMetadataServiceResourceFetcher.readResource(InstanceMetadataServiceResourceFetcher.java:69)
at com.amazonaws.internal.EC2ResourceFetcher.readResource(EC2ResourceFetcher.java:66)
at com.amazonaws.auth.InstanceMetadataServiceCredentialsFetcher.getCredentialsEndpoint(InstanceMetadataServiceCredentialsFetcher.java:58)
at com.amazonaws.auth.InstanceMetadataServiceCredentialsFetcher.getCredentialsResponse(InstanceMetadataServiceCredentialsFetcher.java:46)
at com.amazonaws.auth.BaseCredentialsFetcher.fetchCredentials(BaseCredentialsFetcher.java:112)
at com.amazonaws.auth.BaseCredentialsFetcher.getCredentials(BaseCredentialsFetcher.java:68)
at com.amazonaws.auth.InstanceProfileCredentialsProvider.getCredentials(InstanceProfileCredentialsProvider.java:166)
at com.amazonaws.auth.EC2ContainerCredentialsProviderWrapper.getCredentials(EC2ContainerCredentialsProviderWrapper.java:75)
at com.amazonaws.auth.AWSCredentialsProviderChain.getCredentials(AWSCredentialsProviderChain.java:117)
at com.amazonaws.http.AmazonHttpClient$RequestExecutor.getCredentialsFromContext(AmazonHttpClient.java:1251)
at com.amazonaws.http.AmazonHttpClient$RequestExecutor.runBeforeRequestHandlers(AmazonHttpClient.java:827)
at com.amazonaws.http.AmazonHttpClient$RequestExecutor.doExecute(AmazonHttpClient.java:777)
at com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeWithTimer(AmazonHttpClient.java:764)
at com.amazonaws.http.AmazonHttpClient$RequestExecutor.execute(AmazonHttpClient.java:738)
at com.amazonaws.http.AmazonHttpClient$RequestExecutor.access$500(AmazonHttpClient.java:698)
at com.amazonaws.http.AmazonHttpClient$RequestExecutionBuilderImpl.execute(AmazonHttpClient.java:680)
at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:544)
at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:524)
at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.doInvoke(AmazonDynamoDBClient.java:5110)
at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.invoke(AmazonDynamoDBClient.java:5077)
at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.executeGetItem(AmazonDynamoDBClient.java:2197)
at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.getItem(AmazonDynamoDBClient.java:2163)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.load(DynamoDBMapper.java:431)
at com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper.load(DynamoDBMapper.java:448)
at com.amazonaws.services.dynamodbv2.datamodeling.AbstractDynamoDBMapper.load(AbstractDynamoDBMapper.java:80)
I have 2 timeouts to PUT /latest/api/token, then I get a response. I am not sure what is wrong exactly or why do I have this behavior sometimes, but this leads to latency in my application.
Do I need to modify something in the settings? Is it related to DynamoMapper? Should I use low level Dynamo API?
These issues can occur when:
You call a remote API that takes too long to respond or that is unreachable.
Your API call doesn't get a response within the socket timeout.
Your API call doesn't get a response within the timeout period of your Lambda function.
If you make an API call using an AWS SDK and the call fails, the SDK automatically retries the call https://aws.amazon.com/premiumsupport/knowledge-center/lambda-function-retry-timeout-sdk/. How long and how many times the SDK retries is determined by settings that vary among each SDK. Here are the default values of these settings:
see the SDK client configuration documentation: https://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/ClientConfiguration.html

How to set maxWebsocketFrameSize

getting error:
2020-01-20 21:15:29,599 WARN [io.net.cha.DefaultChannelPipeline] (vert.x-eventloop-thread-0) An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.: io.netty.handler.codec.http.websocketx.CorruptedWebSocketFrameException: Max frame length of 65536 has been exceeded.
at io.netty.handler.codec.http.websocketx.WebSocket08FrameDecoder.protocolViolation(WebSocket08FrameDecoder.java:426)
at io.netty.handler.codec.http.websocketx.WebSocket08FrameDecoder.decode(WebSocket08FrameDecoder.java:286)
Very hard to tell "what" is implementing the websocket server and how to modify the configuration.
Vert.x core has a HttpServerOptions with maxWebsocketFrameSize that "might" be the correct thing to increase, or even the maxWebsocketMessageSize that when increased, might increase the frameSize?
Cannot find any way to clear up this exception when client sends a big message to the server over the websocket channel. (it is text message)

Service Worker DOMException: Registration failed - storage error

While implement Fire-base cloud messaging in browser with help of Service Worker getting an error "DOMException: Registration failed - storage error" please help why i am getting this error
This means that your Service Worker has stored so much data that the storage available to it is full, and upon SW installation it tries to store even more which in turn leads to an error.
You have to either manually remove stuff from your storage or use some library that automatically handles these situations for you in a way or another (eg. removes stuff FIFO style).
In my case the problem was caused by create-react-app's own service worker unregistration logic at the very bottom of index.js:
serviceWorker.unregister();
It was conflicting with the fact of using a service worker in the middle of our own application's logic.
Solution was simple – just removing that line from index.js

Completion queue configuration

Using an async service with a completion queue, is it possible to configure the size of the cq ?
If not, are their any rules applied on the completion queue lifecycle ?
I'm using grpc 1.13.1 and when I looked into the implementation , I didn't find anything like it ( in the server settings nor in the completion queue attributes).
Althought the pending_tags configuration for the GRPC_TRACE variable doesnt work properly on my version ( I get this message : Unknown trace var :'pending_tags' ) , I was able to display the size of the queue enabling 'all' traces.
The question was asked on this thread : https://groups.google.com/forum/#!topic/grpc-io/LTxgMYBx0yk of google groups. Has anything changed since then?
Thnak you
The CompletionQueue API does not expose the 'size' or the number of pending tags on the completion queue. As for pending_tags trace, I believe it is a Debug Only flag, and would only work if gRPC is compiled in Debug mode.

Hitting 100 active connections limit in test env with only two users

I have a single web client and a few Lambda functions which use the Admin SDK. I've noticed recently that I've bumped into the 100 simultaneous connection limit but I really shouldn't be anywhere near that limit. Also it would appear that the connections established by my Lamba functions are not dropping off even after the function has completed.
Any idea on:
how I can prevent this run-up on connections from happening?
how I can release connections established by past Lambda scripts?
how can I monitor which processes/threads/stacks are holding connections?
Note: this is a testing environment I'm working out of so I'd prefer to keep this in the free tier and my requirements should definitely not be running into the 100 active limit. I am on a paid plan in prod.
I attempt to avoid calling initializeApp more than once by using the following connection code. In the example I'm talking about I only have a single database as a backend and so the default "name" of DEFAULT is used each time.
const runningApps = new Set(firebase.apps.map(i => i.name));
this.app = runningApps.has(name)
? firebase.app()
: firebase.initializeApp({
credential: firebase.credential.cert(serviceAccount),
databaseURL: config.databaseUrl
});
I'm now trying to explicitly close connections with goOffline but that leads to another issue where on the second connection -- aka, where the DEFAULT application is already setup and it just reuses the connection already established I get the following logging:
# Generated as result of `goOnline`
Connecting to Firebase: [https://xyz.firebaseio.com]
appears to be already connected
# Listening on ".info/connected" comes back as true, resulting in:
AbstractedAdmin: connected to [DEFAULT]
# but then I get this error
NotAllowed: You must first connect before using the database() API at Object._getFirebaseType
The fact that you have unexpected incoming connections to the database, makes it seem like the stale instances keep an open connection.
Best I can think off is to call goOffline() in your function before it completes to explicitly disconnect. That would probably also mean you have to call goOnline at the start of the function, since it might be running on an instance that previously went offline. Both goOnline and goOffline are synchronous calls afaik, but there's definitely going to be some time between going online and the data becoming available in your app.
If Lambda has a way for you to detect life-cycle events of its instances, that would be the preferred place to call goOffline and goOnline.
admin.initializeApp should only get called once in your script/node app.
The Firebase SDK's talks HTTP2 to the Firebase cloud system, so I'm not sure why you would encounter max connection issues as unique sockets are not stood up per call.
One thing to look out for is that calls to 3rd part API's (such as sendgrid) are not supported on the free tier.

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