We were looking for a job/message queue technology.
After comparing the main ones (RabbitMQ, ActiveMQ, Apollo, ZeroMQ..), we chose Beanstalkd because apparently, compared to RabbitMQ, "It gives 80% the functionality with 20% the weight and complexity".
But while looking how it works, we didn't find any way to send file through this queue system.
Is there a way to achieve that ?
Maybe I should explain our situation. We've got a Web server, and a Local one. What we want to achieve with the queues, first, would be that the Web server "asks" to the Local server to generate a complex PDF, and send it back to the Web server when it's done, so it can be displayed for the visitor.
So maybe that's not the right technology for that ?
Finally it's working perfectly just by reading file content as binary (producer) and writing it on filesystem (consumer), doesn't need any other technology (ftp, shared fs, etc).
Related
I am using Django Rest Framework/AngularJs for developing a web application.
I have a use case in which server needs to stream the contents of a file in realtime, the file itself is growing since some other application is logging in to it. I know many inefficient ways to do this.
Can you suggest some better ways to achieve this. The Django "view" function should not return till the file is growing but still be able to send the incremental data to the client.
Any help will be appreciated.
Hi Im a newbie in stackoverflow!
As mentioned on the question title, I've been storing the email's image path into the db via localhost. Once the email is sent and received, my outlook automatically block the image download and I will need to manually download it (Not a big issue here).
Then I started to wonder what if my website/server is down? If it is down, the email will not be able to locate and download the image at all. So I'm wondering if there is any alternative ways to display the image without worrying bout the availability of my server.
Thanks in advance for any incoming advises/replies!
Since your primary concern seems to be about failure mitigation and not actual coding, I'll direct you to this question.
Your current method isn't actually embedding the images and is making a link. What you want to do is add the images as linked resources. This WILL make your emails larger in size and slower to send, but as long as you aren't a spammer, you should be OK.
Alternatively, you could have an enterprise level failure plan where your server would go offline and a mirrored server in a different location would begin serving up the data/images.
I have a GWT app, which is deployed on the app engine. The application is basically an exam simulator. All the exam questions and answers are stored in an XML file on the server. I use JAXB parser to parse the XML file and send a list of objects to the client through GWT RPC.
I noticed that during the transit (server -> client), the entire data is visible in plain text in Firebug. Since the data (exam questions and answers) are my intellectual property (IP) and something that I give lot of value to, I'm concerned that it's very easy to steal that data. Therefore, I'm trying to find ways to do some basic encryption and obfuscate the content when it's being sent over from the server to the client.
After Googling, I came across gwt-crypto project, and within a few minutes, I was able to achieve the exact result that I wanted. The server would encrypt the data, and the client would decrypt it. In Firebug, it would show the data in encrypted format, and not as plain text.
However, I ran into an issue. After implementing encryption/decryption, I noticed that my application would not load inside my company's network, which is obviously protected by a firewall. The application works perfectly from home or even on a 3G network on my phone. Another version of the application, which does not use encryption/decryption works perfectly from within my company's network. I confirmed this by creating 2 exact same versions of the app, with the only difference between a boolean flag, that determines whether encryption/decryption is enabled or disabled.
I have the following questions here:
What is the best way to achieve the result that I want to achieve? Is gwt-crypto a good solution for that? I'm fine with any simple approach to obfuscate the data during transit. It doesn't have to be a sophisticated algorithm.
What could be the possible reason for a GWT app, with encryption/decryption enabled, not working inside a firewall? I'm really clueless on this.
I'll appreciate any help on this issue.
Using SSL is the right way to go.
In your case, given AppEngine SSL limitations, you should load your HTML normally from non-SSL domain and use cross-site RPC to load your data via SSL domain.
Update:
What is the best way to achieve the result that I want to achieve?
If you want to secure the data in transit then the only secure option is SSL/HTTP. Usually it's also the simplest one as it does not require you to change the application code, just server configuration. In your particular case (appengine with private domain), it takes more work as described above.
Is gwt-crypto a good solution for that?
No. gwt-crypto uses a key to encrpt/decrypt the data. You also need a secure way to discribute this key.
I'm fine with any simple approach to obfuscate the data during transit.
Security through obscurity in not security. It's a false sense of security, which is even more dangerous than no security. It's enough that only one of the technically capable students cracks this and soon everybody would do it.
Possible attack would go like this:
Snoop the network, get username/password of user.
Login as that user, have browser load exam data, which is now unencrypted in memory.
Dump the DOM and inspect it for exam questions.
-
What could be the possible reason for a GWT app, with encryption/decryption
enabled, not working inside a firewall?
Use firebug to make sure network connections are identical, except for the encrypted content. Firewalls should not work that deep. Talk to sysadmin about it.
I want to be able to copy the file I have which comes in as XML into a new folder location on the server. Essentially I want to hold a back up of the input files in a new folder.
What I have done so far is try to follow what has been said on this forum post - link text
At first I tried the last method which didn't do anything (file renaming while reading). So I tried one of the other options and altered the orchestration and put a Send shape just after the Receive shape. So the same message that comes in is sent out to the logical port. I export the MSI, and I have created a Send Port in the Admin console which has been set to point to my copy location. It copies the file but it continues to create one every second. The Event Viewer also reports warnings saying "The file exists". I have set the Copy Mode of the port to 'overwrite' and 'Create New', both are not working.
I have looked on Google but nothing helps - BTW I support BizTalk but I have no idea how pipelines, ports work. So any help would be appreciated.
thanks for the quick responses.
As David has suggested I want to be able to track the message off the wire before BizTalk does any processing with it.
I have tried to the CodePlex link that Ben supplied and its points to 'Atomic-Scope's BizTalk Message Archiving Pipeline Component' which looks like my client will have to pay for. I have downloaded the trial and will see if I have any luck.
David - I agree that the orchestration should represent the business flow and making a copy of a file isn't part of the business process. I just assumed when I started tinkering around I could do it myself in the orchestration as suggested on the link I posted.
I'd also rather not rely on the BizTalk tracking within the message box database as I suppose the tracked messages will need to be pruned on a regular basis. Is that correct or am I talking nonsense?
However is there a way I can do what Atomic-Scope have done which may be cheaper?
**Hi again, I have figured it out from David's original post as indicated I also created a Send port which just has a "Filter" expression like - BTS.ReceivePortName == ReceivePortName
Thanks all**
As the post you linked to suggests there are several ways of achieving this sort of result.
The first question is: What do you need to track?
It sounds like there are two possible answers to that question in your case, which I'll address seperately.
You need to track the message as received off the wire before BizTalk touches it
This scenario often arises where you need to be able to prove that your BizTalk solution is not the source of any message corruption or degradation being seen in messages.
There are two common approaches to this:
Use a pipeline component such as the one as Ben Runchey suggests
There is another example of a pipeline component for archiving here on codebetter.com. It looks good - just be careful if you use other components, and where you place this component, that you are still following BizTalk streaming model proper practices. BizTalk pipelines are all forwardonly streaming, meaning that your stream is readonly once, and all the work on them the happens in an eventing manner.
This is a good approach, but with the following caveats:
You need to be careful about the streaming employed within the pipeline component
You are not actually tracking the on the wire message - what your pipeline actually sees is the message after it has gone through the BizTalk adapter (e.g. HTTP adapter, File etc...)
Rely upon BizTalk's out of the box tracking
BizTalk automatically persists all messages to the message box database and if you turn on BizTalk tracking you can make BizTalk keep these messages around.
The main downside here is that enabling this tracking will result in some performance degradation on your server - depending on the exact scenario, this may not be a huge hit, but it can be signifigant.
You can track the message after it has gone through the initial receive pipeline
With this approach there are two main options, to use a pure messaging send port subscribing to the receive port, to use an orchestration send port.
I personally do not like the idea of using an orchestration send port. Orchestrations are generally best used to model the business flow needed. Unless this archiving is part of the business flow as understood by standard users, it could simply confuse what does what in your solution.
The approach I tend to use is to create a messaging send port in the BizTalk admin console that subscribes to your receive port. The send port will then just use a standard BizTalk file adapter, with a pass through pipeline.
I think you should look at the Biztalk Message Archiving pipeline component. You can find it on Codeplex (http://www.codeplex.com/btsmsgarchcomp).
You will have to create a new pipeline and deploy it to your biztalk group. Then update your receive pipeline to archive the file to a location that the host this receive location is running under has access to.
I want to create a a application in actionscipt 3.0 that allows the user to listen to music and read descriptions of the music. For this to happen i suppose there should be a database where the textbits and music is located and then flash fetch the info when the correct buttons are pushed. The database will contain up to 100 tracks and textbits.
The application will function on a stand that won't have a connection to the internet.
What is the easiest way to do this in actionscript 3.0?
If any of you are familiar with UML and thinks this might help in understanding the problem, then here is use-case and flow-chart:
alt text http://img135.imageshack.us/img135/1498/flowchart2.jpg
alt text http://img27.imageshack.us/img27/1000/usercase.jpg
Thanks in advance.
The easiest way to do what you're asking is probably to store the files in a directory on the machine the application is going to be running on, and then design an XML structure for storing your data. The XML is easily loaded in to Flash at runtime and is easily edittable.
Your other option would be running a database server on the machine, creating web services that run locally and push/pull the data from the database, and then call those services from your Flash application.
The first option is most definitely the easiest and should be able to provide exactly what you need. The second would be more geared towards a distributed Flash application where you needed a central data repository for the clients.
If you're building an AIR application, you can use the integrated SQLITE database. But, i agree with Justin, the easiest way is to use a XML file.
You can probably consider using "Local Shared Objects" which is a kind of cookie, with bigger capacity (100Kb by default, but you can change it). Compared to other solutions already proposed, it has then advantage of not requiring any web server.