oat++ framework/Lobby

oat++

@oatpp_io_twitter

@nikoladsp ,

You can do that.

You can have a proxy in front of all your services which proxies requests + has the swagger-ui for all upstream services.
Or, you can serve swagger-ui in a separate service. Just make sure that you have the correct server address in swagger-ui and that all your services are accessible at that host-name

Nikola Radovanovic

@nikoladsp

@oatpp_io_twitter , many thanks. I will probably go with second approach

shijiantouzouyiqie

@shijiantouzouyiqie

The browser establishes a link with the server websocket and actively sends data. The browser refreshes the page and closes the page for the first time. The server runs normally; The browser establishes a link with the server websocket and actively sends data. When the browser closes the page for the second time, it will send 1001 status code to the server, and the program crashes;
@oatpp_io_twitter Hello, the following is the current code. Is there a better optimization method?

void* StartThread(void* arg);
class WSInstanceListener : public oatpp::websocket::ConnectionHandler::SocketInstanceListener {
public:

.....
public:

  pthread_t m_pid;
  bool m_bQuitThread;
  oatpp::websocket::WebSocket* m_Socket;

};

WSInstanceListener::WSInstanceListener() {
    m_pid = -1;
    m_bQuitThread = true;
    m_Socket = NULL;
}

void WSInstanceListener::onAfterCreate(
        const oatpp::websocket::WebSocket &socket,
        const std::shared_ptr<const ParameterMap> &params) {
    SOCKETS++;
    OATPP_LOGD(TAG, "New Incoming Connection. Connection count=%d",
            SOCKETS.load());

    socket.setListener(std::make_shared<WSListener>());

    m_Socket = (oatpp::websocket::WebSocket*) &socket;

    pthread_create(&m_pid, NULL, StartThread, (void*) this);
    pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
    pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
    pthread_detach(m_pid);

}

void WSInstanceListener::onBeforeDestroy(
        const oatpp::websocket::WebSocket &socket) {
    SOCKETS--;
    OATPP_LOGD(TAG, "Connection closed. Connection count=%d", SOCKETS.load());

    m_bQuitThread = false;
    pthread_cancel(m_pid);
    pthread_join(m_pid,NULL);
    this->m_Socket->stopListening();

}

void* StartThread(void *arg) {
    WSInstanceListener *lis = (WSInstanceListener*) arg;

    lis->m_bQuitThread = true;

    while (lis->m_bQuitThread) {
        pthread_testcancel();
        lis->m_Socket->sendOneFrameText("hello");
    }

    return (void*) 0;
}

 I |2021-12-15 19:46:53 1639568813189617| MyApp:Server running on port 8000
 D |2021-12-15 19:47:00 1639568820630942| Server_WSInstanceListener:New Incoming Connection. Connection count=1
 D |2021-12-15 19:47:06 1639568826556318| Server_WSListener:onClose code=1001
 D |2021-12-15 19:47:06 1639568826556353| Server_WSInstanceListener:Connection closed. Connection count=0
 D |2021-12-15 19:47:16 1639568836406451| Server_WSInstanceListener:New Incoming Connection. Connection count=1
 D |2021-12-15 19:47:21 1639568841210745| Server_WSListener:onClose code=1001
 terminate called after throwing an instance of 'std::runtime_error'
 D |2021-12-15 19:47:21 1639568841210782| Server_WSInstanceListener:Connection closed. Connection count=0
 terminate called recursively

AlexandreHURDYK

@AlexandreHURDYK

Hello.

I've got an annoying issue I'm trying to fix on my oat++ client application : if my server shuts down before it gets the time to send a response to my client after a client request, it causes my client to crash. This is probably a common problem. Any way to fix this client side ?

I can provide an example API call from my client if necessary.

There's probably something I forgot to do.

AlexandreHURDYK

@AlexandreHURDYK

Most basic example : if I call an API function while the server is not up, the client crashes.

As simple as that.

I can try to make a minimal working example.

Is there a way to make my request time out or something ?

Ok nevermind I fixed the problem and I'm stupid : the simple solution was just to surround the API calls with a try/catch.

Nikola Radovanovic

@nikoladsp

hi all, advice needed.
for simplicity, say that there is a DTO User class with id (primary key, auto inc, etc), salutation (mr,mrs, default null) and full name (string).

for all crud methods apart create, id is required field. how is it possible to reuse one DTO in such way that swagger know that id is not present at all while creating user object (excluded from schema) and in all other cases is required? or do I need DTO per crud operation. Additionally, during update, id is the only required field, all others are optional, while reading for example I expect id and fullname to be present and salutation is optional.
is it possible to use some pattern (decorator maybe?) to decouple DTO classes from "business" logic classes. I am interested for this especially in cases of relationships (composed objects, where one holds many others)
thanks in advance

mmn

@mmn:matrix.org

[m]

Is there some easy way to determine the reason why oatpp::websocket::WebSocket::listen() returned? It catches the relevant exceptions and does not return any value, which makes it a bit hard.

Okay, maybe I should abandon listen() and "reimplement" it using iterateFrame().

oat++

@oatpp_io_twitter

Hey @nikoladsp ,

In an ideal world you would have to decouple the DB model and REST DTOs. The way you present data to service users and the way you store data may differ (and they do differ in most cases). Also, it's not recommended to expose DB ids - since they do not describe the actual resource in most cases.

Treat CRUD service as an adaptor of REST interface to DB model.

So the answer is - create two sets of DTOs - one for REST, second for DB.
Read from DB - do whatever transformations/compositions you need - join data in memory if needed - form response DTO and return it on the endpoint.

About the 'ID' problem - follow this issue - oatpp/oatpp#485
We may introduce hidden (from swagger docs) fields in future

oat++

@oatpp_io_twitter

Hey @mmn:matrix.org ,

if the WebSocket connection was closed gracefully - you'll receive the onClose method call in WS listener first, then the listen method will return.
If there was any kind of network issue - listen method will just return - no onClose event triggered.
Here is the implementation of listen - https://github.com/oatpp/oatpp-websocket/blob/master/src/oatpp-websocket/WebSocket.cpp#L279

1 reply

Please note that closed connection - is a normal situation for WebSocket - your application has to have the re-connecting functionality.

Also, make sure to respond with pong messages for all pings

Nikola Radovanovic

@nikoladsp

hi @oatpp_io_twitter many thanks, now to compile some stuff! :D

oat++

@oatpp_io_twitter

The browser establishes a link with the server websocket and actively sends data. The browser refreshes the page and closes the page for the first time. The server runs normally; The browser establishes a link with the server websocket and actively sends data. When the browser closes the page for the second time, it will send 1001 status code to the server, and the program crashes;
@oatpp_io_twitter Hello, the following is the current code. Is there a better optimization method?

Hey @shijiantouzouyiqie ,

Your program is missing a lot of things - and it has critical bugs:

please use std::thread instead of the pthread - just for simplicity and portability
synchronize with mutex access to m_bQuitThread
make sure that the socket is never used after m_bQuitThread is set to true
use sendOneFrameText call inside of try - catch block.

shijiantouzouyiqie

@shijiantouzouyiqie

@oatpp_io_twitter Thank you. I'm trying. I mainly use fewer threads. Set std::thread as a class member or the global does not understand the use of initialization. When I disconnect from the browser, the thread will be disconnected.

shijiantouzouyiqie

@shijiantouzouyiqie

@oatpp_io_twitter Thank you.
Using std::thread, the server can be used normally.

mmn

@mmn:matrix.org

[m]

So for the time being, I'm just deriving WebSocket with my own listen() (and stopListening(); can't use m_listening because it's private) which passes the exceptions through.

shijiantouzouyiqie

@shijiantouzouyiqie

Hello, theoatpp:: websocket:: websocket * m_socket; used here is initialized in the structure as a member variable. It is understood that it should be initialized bym_socket = new oatpp:: websocket:: websocket();. If an error is reported, I don't know how to solve this problem....

oat++

@oatpp_io_twitter

Hey @shijiantouzouyiqie , so what is the question?

1 reply

SSE4

@SSE4

how do I select from PostgreSQL ENUM type into the DTO with oatpp ENUM?

Leonid Stryzhevskyi

@lganzzzo

Hello @SSE4 , just creare a field in DTO with enum. Also, make sure to use enum as string or as a number - depending on your application

You can see an example in exaple-crud

oat++

@oatpp_io_twitter

Hey @SSE4 - https://github.com/oatpp/example-crud/blob/master/src/dto/UserDto.hpp#L22

That example is for SQLite, but there is no difference

actually - here is the PostgreSQL example - https://github.com/oatpp/example-postgresql/blob/master/src/dto/UserDto.hpp#L22

SSE4

@SSE4

thank for the help. I made it work, I had to add a cast to my SELECT QUERY: CAST({0} as text)

otherwise, I was getting an exception: [oatpp::postgresql::mapping::Deserializer::deserializeString()]: Error. Unknown OID.

Zach

@acidtonic

I keep fighting some odd linker errors about missing vtable/constructors for DTO files even though they are correctly defined when linking across a few projects. But since the DTO's are only headers the static library for the DTO's are 8 bytes and basically empty.

I link everywhere else but on windows I get errors about the Vtable for the API-Client DTOs

Not sure what I am missing. I actually have two projects and one links but the other doesnt. Both use the same API library and dtos, just trying to track down why

Leonid Stryzhevskyi

@lganzzzo

Hey @acidtonic , I had before some errors with header only libraries. I ended up just adding an empty .cpp file. Just didnt want to spend time on that

Zach

@acidtonic

I have unfortunately a large multi-part project structure and I'm not sure if it's my fault or not :)

Likely is.... I'll probably follow your advice and throw in a cpp file

Zach

@acidtonic

Can I make the DTO's also contain a cpp or will that break the codegen?

I suspect the client-dto-lib is actually empty and brining no extra symbols over, but the dtos are reachable at compile time so I only get a link error. Still somewhat confused how

Leonid Stryzhevskyi

@lganzzzo

Can I make the DTO's also contain a cpp or will that break the codegen?

No, it wont break anything

I suspect the client-dto-lib is actually empty and brining no extra symbols over, but the dtos are reachable at compile time so I only get a link error. Still somewhat confused how

Can you please post the actual linker error

Mo Aboulmagd

@Maboulmagd

@oatpp_io_twitter I was wondering, how often do websockets disconnect? i.e Is it once every 10 hours, or does it depend on the host that I am listening to and their rules? Also, is there an implementation of the reconnecting functionality, that I can take a look at? Or is it as simple as using the connector to reconnect to the endpoint I am interested in, and resubscribing to streams that I was initially subscribed to?

oat++

@oatpp_io_twitter

@Maboulmagd

I was wondering, how often do websockets disconnect? i.e Is it once every 10 hours, or does it depend on the host that I am listening to and their rules?

Yes, It depends on the host rules and on the internet connection.
If you want your events stream to be stable - you should have a reconnect functionality.

Also, is there an implementation of the reconnecting functionality, that I can take a look at? Or is it as simple as using the connector to reconnect to the endpoint I am interested in, and resubscribing to streams that I was initially subscribed to?

Yes, it's just as simple as using the connector to connect again.

1 reply

AlexandreHURDYK

@AlexandreHURDYK

Hello. It's me again.

I'm trying to shove the content of a std::vector<bool> object inside a List<Boolean> DTO field, but the compiler isn't very happy about this and tells me there is no matching member function to call puch_back(), which is kinda strange because I managed to shove a std::vector<std::string> inside a List<String> DTO field without trouble.

What's the issue here ?

Here's the code bit you may want to see :

auto dtoEndosInfos = EndoResponse::createShared();

dtoEndosInfos->nbFiles = vecInfos.nbFiles;
for (int i = 0; i < vecInfos.nbFiles; i++)
{
    dtoEndosInfos->name->push_back(vecInfos.name[i]);
    dtoEndosInfos->isStamp->push_back(vecInfos.isStamp[i]);
    dtoEndosInfos->block->push_back(vecInfos.block[i]);
}

My DTO declaration while we're at it :

class EndoResponse : public oatpp::DTO
{
    DTO_INIT(EndoResponse, DTO)
    DTO_FIELD(List<String>, name);
    DTO_FIELD(List<Boolean>, isStamp);
    DTO_FIELD(List<String>, block);
    DTO_FIELD(Int32, nbFiles);

};

Where communities thrive

People

Repo info

Activity