Looking for Guidance for External Native TCP Service Fabric Client - external

I have a number of native TCP-based Service Fabric applications running in both stateless and stateful modes. I've been experimenting the creating a custom external SF client implementation using native TCP via RPC calls. As the SF Service can push data down to clients we need a persistent connection. I've been playing with ICommunicationClient and ServicePartitonClient and that seems clear enough; however, I am looking for some guidance regarding how to best handle the "ValidateClient" method in my implementation of CommunicationClientFactory. I've studied this reference quite a bit: Communication clients and factories; we already have a working TCP Client that works less service fabric. My thinking is that I just need to use the SF Client SDK to get a secure connection to the ServicePartiton and the exposed TCP endpoint. I hope that members of the Microsoft SF team or any knowledgable person can point me to other resources; this terribly exciting stuff - I hope there is a way forward.

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Exposing a Postegres / Patroni db on Openshift to outside world

I am planning to run an SSIS ETL job , which has a sql server as SOURCE db , this is on a physical on-premise machine and the DESTINATION db (postegres/patroni) is running on Openshift platform as pod/containers. The issue I am facing now is like, DB hosted on openshift cannot be exposed via tcp port. As per few articles online, openshift only allows HTTP traffic via “routes”. Is this assumption right? If yes, how in real world people run ETL or bulk data transfer or migration to a db on openshift from outside. I am worried to use HTTP since I feel , it’s not efficient for ETL. Few folks mentioned like, use OC PORT FORWARDING. But for a production app, how an open shift port forwarding be stable? Please throw your comments
In a production environment it is a little questionable if you want to expose your database to the public internet. Normally you probably rather want to go with a site-to-site VPN.
That left aside it is correct that OCP is using routes for most use cases, which are then exposing an http(s) endpoint. If you need plain TCP however, you can create a service of type loadbalancer.
The regular setup with a route is stacked like
route --> service --> pods where the service is commonly of type clusterIP.
with a service of type loadbalancer, you eliminate the route and directly expose a TCP service.
If you run on a public cloud, OCP takes care of the leftover requirements for you. Namely that is to create a Loadbalancer with your cloudprovider. In the case of AWS for example, OCP would create an ELB (Elastic Loadbalancer) for you.
You can find more information in the documentation

Hosting html file over mosquitto

I just found that mosquitto had got a websockets upgrade which allows it to
host the HTTP services.
I tried hosting a html file using the websockets feature on the port 8080.
The mosquitto broker seems to start fine and the mqtt services on the other ports seem to function properly. But when i try to access the html file over the localhost I get the a response saying no data sent by the server.
I am not sure where my mistake lies..Any ideas?
Mosquitto is not a HTTP server, it can not serve generic files.
The HTTP listener is only there to facilitate an upgrade to the websocket protocol in order to run MQTT over a websocket connection.
You might want to look out for a different broker that is flexible enough to do what you're looking for. I don't know of any MQTT broker that allows you to do that out of the box, but many are fairly extensible. For one I can talk about is VerneMQ, as I am one of the core developers. Developing a simple VerneMQ plugin that serves some static files over HTTP is a matter of a few lines of code, as the plugin only requires to setup some configuration for the internal webserver.
However, unfortunately we haven't yet documented this feature. But feel free to drop us a line if such an approach sounds interesting for you.
Cheers,
Andre

Different Between rpc (remote procedure call) and webservices

I wanna know the basic different between rpc and webservices. which should be prefer.
I wanna choose between json-rpc and jax-ws.
Web service:
Web services are typically application programming interfaces (API) or Web APIs that are accessed via Hypertext Transfer Protocol (HTTP) and executed on a remote system hosting the requested services. Web services tend to fall into one of two camps: big Web services and RESTful Web services.
RPC:
Remote Procedure Calls. It enables a system to make calls to programs such as NFS across the network transparently, enabling each system to interpret the calls as if they were local. In this case, it would make exported filesystems appear as thought they were local.
Which one is preferable:
RPC would be used only for internal/in-house servers where you have influence on both the client and server code. The most frequent case is to forward services which only exist on a few machines. For example, to minimize the number of licenses or support overhead needed by forwarding requests to a central machine, or to provide access to software that is other operating system specific (eg, Linux programs that need to use an old program only available on SGIs.) The other case is to reduce startup costs.
We can identify two major classes of Web services, REST-compliant Web services, in which the primary purpose of the service is to manipulate XML representations of Web resources using a uniform set of "stateless" operations; and arbitrary Web services, in which the service may expose an arbitrary set of operations
May it will be helpful to you...

How to automatically detect a server?

We have developed a client app and a server app. The client communicates with the server using the http protocol and sends some data to be processed by the server.
Our structure allow us to have the server installed anywhere. I can be on the same client network or even on the cloud.
When the server is hosted on the cloud, it makes sense asking the user for the server address (since it can change if the user wishes to) but it does not make sense when the server is on the same network that the client. Besides that, we are currently asking users to configure the server ip/name in order to connect to the server.
To avoid this (asking users for the address) I have developed a discovery service based on UDP. The client broadcasts a message that the server answer with its address. It does work on some cases, but it does not when the user has some kind of firewall, proxy or even an anti virus.
I have read a lot about discovery services, and the one that a like most is Bonjour.
So, the question is: what is the best way of discovering a server's IP when the server is on the same network that the client without being blocked by firewalls, proxies, etc?
You can keep your service purely local (in the intranet) and build on top of what you are using now by implementing hole punching. You can get past firewalls, but Im really not sure about AV software policies.
Or you can establish a well-known http-based discovery service in the internet.
A server comes alive, sends its (local) ip address to the discovery service (keeps sending keep-alives)
On startup, the client queries that discovery service, identifies the local subnet he is in, and gets back the local ip address of the server.
That of course creates a single point of failure in your system in that if the discovery service kicks the bucket, your clients cannot find servers. You can remedy that by replicating the service and/or introducing fallback mechanisms (like the purely local discovery you have), which you probably want to do anyway. The only problem you might have is the subnet identification, if computers in local subnets dont share external IP addresses (then it depends on what a local subnet is for you).

tcp socket server to test html5websocket

Which is best tcp socket server to testing html5websocket? I developing a html5socket based client that will interact with tcp. So I want first a testing server. I am good in PHP but not in sockets programming. So I used PHPwebsocket downloaded from google code. I tried it using its own client and server for testing but it suddenly disconnects and not work as intended so is there any other socket server to test HTML5 websocket client? Which one is better, I can use a python based, or java based tcp server or if in PHP then that can be more convenient. And please tell me what else I need to test HTML5 websocket. I am newbie in sockets. So my concepts are not so clear.
thanks for any advise.
If you want to self host then:
pywebsocket - Python
jwebsocket - Java
jetty with WebSockets - Java
You could connect to the Pusher hosted WebSocket API to see if you can connect. More information on the endpoints and Pusher protocol here:
http://pusher.com/docs/pusher_protocol
You would need to sign up for a free Pusher sandbox account to do this though.
You say you want to "interact with tcp". Do you have specific protocols in mind? If using JMS, XMPP, or AMQP, the Kaazing WebSocket Gateway provides these industry standard APIs and protocols in the browser out-of-the-box. For example, using JMS, you can build pretty complex messaging applications without a single line of server-side code. Everything can run in the client (typically in JavaScript in the browser).
Here are some examples showcasing the power of extending rich business protocols all the way to the browser.
Also, the Kaazing gateway comes with free development license; fully functional server for up to 50 concurrent connections, no functionality or time restrictions.