I have multiple page app with login, users, permissions and functional area. How should structure my ember routes. Should i put all the screens in one page. which does not look ideal.
Should i create ember routes for each page? Like for users. create/edit/delete. which looks reasonable to me. I am thinking on these lines.
How should you transition from one page to another page. Like from users to permissions page. Should i use window.location.replace or something like that based on condition, move to another page?
How can i pass parameters like userId, sessionId to other pages. I dont want to use get method. I can use local store but not sure whether there are better ways and what is the common practice generally followed.
I know it depends on project to project. But would be nice to understand, what did you use?
All of your questions are answered in the basic Ember guides: http://emberjs.com/guides/
The big advantage of Ember is that it contains a very sophisticated state engine that manages your routes for you. Once you learn the basics of Ember, your questions will be answered. Another hint: stop thinking in terms of "pages" and start thinking in terms of resources, nested resources and routes. Getting stuck on the concept of a "page" will just get in your way.
Related
I'm developing a Web app (unfortunately a legacy one) in java (that runs on tomcat) with a very small, but not well organized (at least on this particular project), group and let me start by saying we have not much of experience in servlets programming.
The issue is the folloing.
I'm having kind of a trouble as the amount of servlets keep growing and growing while we implement new functions in this webapp. We don't have a project to follow and structure. Just the clint who randomly asks for new functionality out of the blue.
I would just say our web.xml is a mess. I think we should avoid to pollute the web.xml so much with new servlet every time (right now is about 800 lines and it's becoming hard to maintain), but i'm not sure about what i should do about it.
I'm exploring different possibilities, but we can't afford to explore too much so i would like to hear some idea or best practies from people with more experience than us.
I was thinking that maybe we should use CORBA ore something like that to implenet some kind of RPC. So while grouping common functionalities in a few bunch of servlets we could tame the chaos. Could it be a good idea?
What i have in mind is something like a few servlets that pose as entry points for the requests. I would like to group them by the type of response they give. So for example i have a servlet that serves me json after calling some other class that actually do the job to extract data ore manipulating data. Or again i would have a servlet that serves me files, files that another class or servlet produce. And so on. Am i looking at the problem in the right way?
I took a looked at some framework like DWR (Direct Web Remoting) but we would need to integrate it with a legacy webapp with ugly jsp pages full of scriptlet and we can't afford to jump into full ajax web pages in the limited time we have for the project.
We would need something more lightweight.
The more i search for a solution the more i get confused and overwelmed by the possibilities i find (REST, ORB, RPC, JSON-RPC...), so i ask for your help. Thanks in advance for every answers and tips.
You should definitely look into the Spring framework which is the de-facto standard for Java web development nowadays: http://projects.spring.io/spring-framework/
The Play Framework is also an interesting framework, giving you a Ruby-like development cycle: https://www.playframework.com/
Hello many of your points are valid so you can use new frameworks like spring or struts but it needs huge change over as many new levels will get added/introduced.But if you want to just get ride of many servlets you can/should use MVC architecture like framework in addition to that use a central level controller(a main servlet)-this will just take the request and checks in it (like switch case) as soon as switch case matched that helper class / utility class should called via instance or statically after that the response should also from that helper/utility class and should be sent to the main controller and that main controller will send it to respective jsps/html.
I have a Spring MVC project in Java. This web app can be accessed by multiple users in different browsers. I haven't coded any session bean in my program.
Now I want to 'crash'/'timeout' the browsing of one of the users, while other users will go on with their normal expected browsing. I want to do this to see if this action has any effect on the shared variables.
What kind of coding I need to do for this? Thanks in advance!
It is not at all clear what you are trying to achieve here, but I'm assuming that you are doing this as an experiment ... to see what happens.
You could modify the webapp to implement some special request, or request parameter, or request parameter value that tells the webapp to crash or freeze the request being processed. Then send that request from one browser while others are doing "normal" things.
Whether this is going to reveal anything interesting is ... questionable.
Another interpretation is that you are aiming to include timed out requests and other things in your normal testing regime. To achieve that, you would need implement some kind of test harness to automate the sending of requests to your server; i.e. to simulate a number of simultaneous users doing things. There are various test tools for doing that kind of thing.
I'm working on a site containing real estate listings in Spring MVC. I would like to prevent scripts to steal the content by scraping the site. Does anyone have experience with techniques that can easily be plugged in to a spring mvc environment?
User-agent is too simple to circumvent.
One idea I had was to keep track of two counters on the serverside.
ipaddress --> (counter xhr request, counter page request)
the counter page request is increased with a filter
the counter xhr request is increased on document ready
If a filter notices the two counters are totally out of sync, the ip is blocked.
Could this work or are there easier techniques?
Cheers
edit
I am aware that if scrapers are persistent they will find a way to get the content. However, I'd like to make it as hard as possible.
Off the top of my head:
Look for patterns in how your pages are requested. Regular intervals is a flag. Regular frequency might be a flag (four times a day, but at different times during the day).
Require login. Nothing gets shown until the user logs in, so at least the scraper has to have an account.
Mix up the tag names around the content every once in a while. It might break their script. Do this enough times and they'll search for greener pastures.
You can't stop it at all, but you can make it harder as much as possible.
One way to make it harder is change your content URL very frequent base on time with appending some encrypted flag in url.
Some of suggestion are in given link.
http://blog.screen-scraper.com/2009/08/17/further-thoughts-on-hindering-screen-scraping/
http://www.hyperarts.com/blog/the-definitive-guide-to-blog-content-scraping-how-to-stop-it/
Load the content via ajax.
Make the ajax request dynamic so they cant just go and scrape the ajax request.
Only sophisticated scrapers support execution of java script.
Most scrapers dont run the pages through a real browser, so you can try to use that to your advantage.
We have a system that comprises of several functions and I am requested to separate some functionality from our existing system.
Basically, the system have only one user which has access to the whole system functionality, however, the requirement here is to limit the access some users have to the system.
I would appreciate some kind help in the direction i am suppose to take with this assignment.
Thanks in advance
PS if its not clear enough you can follow up by comment.
The first question you need to answer is - where do you want to keep your access information? i.e. who can access what. some options include a LDAP server, hard coding into the app, or some sort of encrypted file, etc. How you asnwer this will dictate the technology you use.
For example, if you decide to use a LDAP server, then you need to have your app setup a connection to it, prompt the user for a userid and password, logon, and retrieve their security groups. Then when you are setting up the GUI, you can query the retrieved groups to see what the user can see or access.
It's pretty much always a good idea to relate a user to one or more security groups. From there you can decide to either assign GUI functionality to individual groups, or to decouple a step further and assign function to privilages, and then define group to privilage relationships.
Java comes with JAAS which is a built in security framework. But it can take some time to get your head around and (AFAIK) is not a completely solution, just a starting point.
It also may be that you simply don't need anything as complex as LDAP and JAAS. If it's a simple app then perhaps you only need an admin id which only one or two people know the password to, and some shared other ids, in that case you can simply store the data in the app. Although this is the least flexible solution.
Finally you should make sure that the difficultly of accessing the system should match the importance of the information being stored. ie. don't put bank level security in front of editing the staff's contact information.
I have been handed a large Spring - Hibernate project and have been told to go through the code and figure out how it works.
I have been able to run the project in JBoss and access pages locally, but I have no idea how to figure out how the program is layed out, as I have no web programming experience.
I have been told that it is "pretty simple" and is a "normal Spring-Hibernate project."
Any idea where to begin?
Well, for starters, you'll really need to learn at least the basics of how these frameworks operate. Here's a tutorial on Spring MVC, and here's a Hibernate tutorial.
You'll need to identify the classes that create the various layers; there are certainly going to be Controller classes (which take a web request and figure out how to construct the response) and DAO classes (Data Access Objects, which manage saving and retrieving data).
There will probably be JSP files which describe the views; that is, what the user sees. The HTML code that builds the actual web pages should be here.
My suggestion: pick one simple page and follow it through. Where's the JSP that sets up the HTML for that page? Where's the controller it gets POSTed to? Does that controller call a service class or a DAO? A validator? Etc. -- type in one bit of data and follow it all the way through. It will help to have an IDE that shows you the structure of the application, and allows you to go into debug mode and step through the code.
Good luck!