I looked at the StrongLoop documentation and modules, but couldn't find anything except websocket support.
I was wondering if anyone has made an implementation of it yet, how did it go ? How is it doing? And if it's something that the StrongLoop team is planning on adding soon.
W3C Spec for SSE: http://www.w3.org/TR/2009/WD-eventsource-20090423/
Related
I am working on designing a workflow with the intention of using cadence workflow engine and Java client. Seems like uber is actively using Go, and thus Go has better documentation and Activity and other classes than Java Client. Is this true?
No, it is not really true. The majority of the open source users of Cadence and Temporal are using Java SDK.
If you go the the java-client channel in Cadence slack, the community has more discussion than go-client. Even in Uber, Java-client is heavily used by core services like payments.
Go client happens to have more docs/samples because it started a little earlier. In fact, the docs that are missing in Java, could be derived from Go. It should be noted that there are more documents in Java library. For example, the documents of how to write unit tests, instead of putting in to cadenceworkflow.io, we put in
javadocs directly. Because this is the convention for Java developer to lookup documentation.
IMO they are the same important for Cadence. All the new features are implemented/rolling out at the same time hence they don't have real difference.
I am entirely new to the OPC-UA world.
I need to establish a proof of concept of how to allow our ERP to communicate with PLCs. I am evaluating software that acts as an OPC-UA server (it is working). I found about Milo and got the code working in Eclipse. Looking at the examples, I got a toy program connected to the OPC-UA server and doing... something.
The basic plumbing works, but I can't figure out where to start with OPC-UA and Milo. I have not been able to find introductory material to help me make sense of it all.
Is there documentation about the architecture of OPC-UA and how Milo implements that? Is there a better way to go about it than looking at the examples to figure out how things should be done?
Documentation for Milo is one of the next major things to tackle now that we've got a release published to Maven central. Even once that documentation exists, though, it will assume some knowledge of OPC UA.
There's a somewhat expensive green book called "OPC Unified Architecture" available on Amazon. I haven't read it myself, but I've heard other people mentioned they have. It's probably a lot easier and cheaper than trying to learn OPC UA from the specifications.
edit: Seems there's a couple other cheaper alternatives now too.
The Milo project has a gitter channel and a mailing list you can ask questions on as well.
I'm starting a project with requirements such as NLP, storage of semantic data, content managment etc. and Apache Stanbol seems like a nice fit, but I'm not exactly sure it's ready so I'm trying to make an appropriate assessment before starting to work with it, as there are few things that worry me:
Stanbol seems a bit young and immature (newest version 0.12). Has anybody used it in a commercial project/application/setup (I failed to find this information online)? What is the scale of those projects?
How horizontally scalable is Stanbol? What are its cloud/clustering capabilities? As far as I know it relies on Apache Jena for storage, and Jena storage isn't horizontally scalable which would make Stanbol unable to scale horizontally as well. I might be wrong about this, but this is my current understanding, please correct me if I'm wrong. Maybe Jena can be swapped with something else to be used as RDF storage provider and I'm not aware of it?
Learning resources for Stanbol seem a little scarce. Does anyone know of a place/book/whatever where I can get more understanding about Stanbol under the hood (other than the official Stanbol website and the IKS website)?
Are there any good alternatives? I know there are nice alternatives regarding NLP (e.g. GATE, UIMA), but they lack CMS capabilities.
Thanks.
To your question:
1) I've been working on a project involving Stanbol(version 0.10). Its
still in the pre production stage. For CMS, we evaluated JackRabbit
and Alfresco. Alfresco (CMIS) was found to be a better choice in our case. What I
like about stanbol is the enhancement chains and the set of
Enhancement
Engines
that come by default. This is a small to mid size project.
3) I found this book (Instant Apache Stanbol, Packt Publishing)
very practical and useful while going about with my work especially the sections on Entity hubs and Enhancement engines.
A viable option is to use Redlink that offers content analysis and linked data services in the cloud using Apache Stanbol and Apache Marmotta in the back-end.
The Readlink team has worked on IKS and Apache Stanbol; for these reasons getting in contact with them can be a good starting point when deciding to use these technologies in production environments.
While this sounds silly, I haven't been able to find a way to get the IP of the client in Play 2.0. It was available in 1.2.x as Http.Request.remoteAddress, but 2.0 (I primarily checked the Scala API, but I did a quick check of the Java one too) only seems to provide information about the server side of the request in play(.api).mvc.Request. Is there something I'm missing? The closest hack I can think of right now is setting it up behind a reverse proxy and then checking X-Forwarded-For, but this doesn't work too well in dev.
EDIT:Coming back to this answer, this was added in playframework 2.0.2: see release announcement on https://groups.google.com/forum/#!msg/play-framework/Z97GQ2VnR5M/T-STGaeuN68J%5B1-25%5D and more importantly the API documentation at http://www.playframework.org/documentation/api/2.0.2/scala/index.html#play.api.mvc.Request
As you can see there is now support for Request.remoteAddress
Original:
There is currently a bug open for this in the tracker: https://play.lighthouseapp.com/projects/82401/tickets/256-add-back-requestheaderremoteaddress
I think that hacking the play2.0 libraries to include the linked patch is currently the best bet. It is probably still cleaner than to use a proxy with the sole purpose of adding XFF headers, and using those to determine the IP.
Please check this Github project at https://github.com/orefalo/play2-xforward
I took the code from Play1 and ported it to Play2, it should work the same.
Still a work in progress...
I am new to Blackberry app development. I need to call REST webservice from blackberry application using JDE 4.7. I searched but not got any solution. Anyone help pls?
sri
You have to make an HttpConnection request and read the data as an InputStream... have a look at this tutorial Calling REST based web services
I appreciate this an old post - but it has been updated so someone is looking at it, so I thought it appropriate to contribute.
I am sorry, but I can not recommend the code supplied the link from another answer called "Calling REST based web services".
I have made a comment explaining this on the site, along the following lines:
"In my opinion this code is flawed because it does not consider the different connection methods, nor does it consider different encodings. More over it does not consider the Event Thread or provide reasonable error checking and logging. I appreciate that this is just a sample, but I think the author has a responsibility to make people who might use this code aware of how it should be used properly. And this code will cause more problems that it solves. Refer to the supported BlackBerry documentation and web sites for better samples."
Sorry, I am not as familiar as I should be of the questions asked on stackoverflow, but questions like this come up regularly on the BBRY forum here:
http://supportforums.blackberry.com/t5/Java-Development/bd-p/java_dev
I recommend that you go on that forum and type network in the Search box on that site and you be presented with a range of tutorials and KB articles that discuss all aspects of networking. In this particular case I would recommend this:
http://supportforums.blackberry.com/t5/Java-Development/What-Is-Network-API-alternative-for-legacy-OS/ta-p/614822
Networking is not trivial on the BlackBerry, do not expect a cut and paste of the code supplied to work for you. Specifically you should be aware of:
a) The various connection methods, the costs associated with each and the impact that using each might have (e.g. transcoders or caching)
b) The Event Thread, how to get off it and back on when processing a response
c) Logging and reporting so that you can investigate problems when they occur (and they will).
Personally, given that all OS 4.7 devices can be upgraded to OS 5.0 and should be, since OS 5.0 is better, I would forget supporting OS 4.7. Instead look at OS 5.0 and above support and use ConnectionFactory.