Native client or what? - google-chrome-app

I have some c libraries for image processing and optimizing.
Should I port my c libs to native client for publishing as chrome app?
Is there any other way to use the c libs?

Native Client (NaCl), or Portable Native Client (PNaCl) are great options, this guide can help you choose between NaCl and PNaCl. They will offer the best performance. Should you want to deploy to other browsers that don't support NaCl, you can investigate pepper.js, and do your port with those additional constraints. That will enable you to use either [P]NaCl or Emscripten.

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Web Socket: IIS WebSocket Protocol feature need to be enabled for Socket.io?

For one of my application, I have implemented Web socket using socket.io and hosted in IIS. Currently socket connection helping to provide two way connection between client (React) and server (node.js).
As I mentioned, I have hosted my application in IIS. I have few doubts regarding Turn Windows features on or off -> Internet Information services -> World wide Web Services -> Application Development Features -> WebSocket Protocol. I have tested my application without enabling this feature, its working fine, but I would like to confirm below stuffs.
WebSocket Protocol
Do I really need to enable WebSocket protocol feature to make websocket work in my application? If so, how now it is working fine without enabling (I haven't do performance and stress testing, I may face issue on this).
What if I not enabling this feature? in short what is the actual use of this feature?
It would be helpful if anyone answer the above questions. Thanks in advance.
WebSocket as part of the HTTP stack requires a bunch of things to be ready on Windows (across multiple components), so hope this answer helps a little.
HTTP.sys, a driver deep down in Windows OS, is upgraded to support the necessary packet communication required by the protocol.
The IIS WebSocket module, an IIS extension which many other Microsoft frameworks (like SignalR) depend on.
So WebSocket support is by default on in HTTP.sys, and you don't need the IIS module if your framework (socket.io) has no dependency there.
Note that the "Summary" section provides several useful links,
https://learn.microsoft.com/en-us/iis/get-started/whats-new-in-iis-8/iis-80-websocket-protocol-support#summary
and the same article also reveals that IIS WebSocket module has
conflicts with socket.io.

Leshan connect to server and cloud

I have the task of implementing iot device management using Eclipse Leshan. I have difficulty understanding how Eclipse Leshan works in connecting IOT sensors with servers and cloud. Is it true if I declare that Eclipse Leshan does not require a gateway like Eclipse Kura to connect into server and cloud?
Does anyone know where the complete documentation about Eclipse Leshan is? it would be very helpful if there were examples of programs in implementing the eclipse leshan.
Thank you
Eclipse Leshan is a library for implementing applications that use the LWM2M protocol to manage devices. As such, your application can use Leshan's Java API in order to interact with devices that also support LWM2M.
LWM2M does not per se mandate a transport protocol. However, the spec is written assuming that CoAP over UDP is used for that purpose. In fact, the LW in LWM2M stands for Lightweight and as such, using CoAP as the transport protocol makes a lot of sense for managing constrained devices.
Eclipse Leshan itself does not connect to a server or cloud but instead is usually part of an application that is hosted on a server (on the cloud). However, you need to implement that application yourself because Leshan, as indicated above, is just a library. The devices then interact with your LWM2M enabled application. Because CoAP/UDP uses standard IP, this interaction can occur over public internet infrastructure if desirable in your use case, i.e. no gateway is necessarily needed. You can, however, also connect your devices to a local gateway, e.g. Kura, and then connect the gateway to your LWM2M server in the cloud instead. It really depends on your use case and the capabilities of the devices.

MongoDB's "mongosniff" for windows

I need to see the request/response to a mongo server. MongoDB has an application called "mongosniff", but it isn't available on windows.
What is my alternative? Fiddler?
mongosniff isn't included with the binary download for Windows, but you can compile it yourself if you are patient and so inclined. You will need to install developer tools including Git for Windows, Scons, and the WinPcap developer's pack so this certainly isn't a quick path.
I would instead recommend downloading Wireshark which is a cross-platform network protocol analyzer. In fact, I would recommend using Wireshark in preference to mongosniff even if you aren't using Windows.
Wireshark also uses the WinPcap library and provides a much more comprehensive user interface than mongosniff as well as a huge selection of supported protocols including the Mongo Wire Protocol.
Fiddler is a web proxy for debugging HTTP/HTTPS traffic, and isn't directly relevant to the Mongo Wire Protocol. You could use Fiddler to inspect a web interface (eg. REST API), but it does not decode lower level protocols.

Oracle access from iOS

I'm developing an iPad app that needs read-only access to an Oracle database.
Is there any way to do this? As far as I can see, the only options are using OCI, which requires a prebuilt binary in the form of the instant client (and not built for ARM), or OJDBC drivers. Both of these seem to be out of the question.
In my research I have discovered that libmysqlclient compiles for arm with minimal tuning. This is a stretch, but is there any possible way to use this to my advantage?
I have seen this product providing odbc connectivity through the use of a Windows gateway machine using the ODBC client libraries, but this solution really isn't an option for me at the present time.
Any ideas?
At the very bottom, there are only two libraries for accessing Oracle:
The OCI binary library.
The Java OJDBC Jar file.
All other libraries (such as ODBC, ADO.NET) build upon one of these libraries (usually on OCI).
There's no OCI library for the iPhone (or any ARM architecture as far as I know) and there's no Java VM to use OJDBC. So you cannot directly connect from the iPhone to an Oracle database.
So whatever your solution will be, it'll require an intermediate server (or gateway).
While I did end up using an intermediary server... I have since realized that this isn't strictly necessary. Direct access should be obtainable by using the OJDBC drivers directly on iOS using gcj to compile them for ARM. Since Objective-C is a superset of C, you could use JNI for communication to and from. Hope this helps anyone who comes here :)
Direct access to an Oracle database from iOS is not possible as of this moment. Exchanging data with an Oracle database by means of web services is fairly simple. You can use APEX for this, lean and mean.

Google Web Toolkit on a standalone server

Our team is planning on making a thick client into a web based UI. We are researching the various options and GWT is something that we are researching. I have a question if GWT can be deployed by itself (meaning, does it have a built-in web server that can be deployed as a solution?) Appreciate thoughts about it.
Thanks in advance.
If your application is completely client-side and does not need to communicate with a server (for data purposes), then you can use any web server. GWT compiles to static JavaScript files, so you can use apache or any other web server to serve up the static files.
If there is a server-side component to your application then you'll need a servlet container.
No built-in web server really except for the development platform which include one... but it's not meant for production.