I am sorry in advance; I am just learning Web development and my knowledge of it is quite limited.
I will describe my problem first.
I have relatively large amount of data (1.8-2 GB), which should be hidden from a public web access. However, a user should be able to request via url call a specific small subset of data and see it on his / her webpage.
Ideally, I would like to write a program on a web server. Let's call it ./oracle, which stores the large amount of data in primary memory.
Each web user should be able to make a specific string calls to oracle and see oracle'sresponse on a web page as html elements.
There should only one instance of oracle, and web users should make asynchronous calls to it.
Can I accomplish the above task with FastCGI or any other protocols?
If yes could you please explain which tools / protocols should I use / learn?
I would recommend setting up an Apache server because it's very common and you'll be able to find a lot of answers to any specific questions here on StackOverflow already.
You could also look into things like http://Swagger.io which can help you generate your API.
Unfortunately, everything past this really depends on what you use to set up your server. Big picture though:
You'll need to open up a port to listen to incoming requests
You'll need to have requests include the parameters they want to send to oracle
You could accomplish this the URI, like localhost/oracle-request?PARAMETER="foo"
You could alternatively use JSON in the body of the http request
Again, this largely depends on how you set up step 1
You'll need to route those requests to the oracle
This implementation depends entirely on step 1
You'll need to capture the output from the oracle and return it to the user
Once you decide on how you want to set up your server, feel free to edit your question and we may be able to provide more specific help.
Related
To start off, I am extremely sorry if my question is not clear but I have very little knowledge about web services in general and the vast nature of varying available information has driven me crazy over the past few weeks. So please do bear with me.
Summary: I want to create a live score update app for android. (I haven't added android as a tag because I do know how to retrieve data from say twitter's JSON api.) However, like the twitter JSON api, I want to be able to add(POST maybe?) data to the Apache 7.0 service that I have running. I then want the app to be able to be able to retrieve this data that I have posted.
I had asked a more generic question earlier and I was told that I should look up some api's. I did that but I have still not been unable to make a break through.
So my questions is:
Is setting up an API on my local web service the correct way to do this?
If so, how can I setup an API that will return JSON objects to the Android app. Also, I would need to be able to constantly update this API with new data.
Additionally, would I also need to setup a database for all this?
Any links to well explained matter would be appreciated too.
Note: I would like to carry this out using a RESTful Web Service through Jersey and use JSON Objects during retrieval.
Again, I am sorry about my terrible knowledge with web services in general despite trying my best to research a lot. The best I could do was get my RESTful Web to respond to a GET with some pre-defined text that I had set in Eclipse.
Thanks.
If I understand you correctly, what you try to do is something like this:
There will be a match or multiple matches of some sort. Whenever a team/player scores someone (i.e. you) will use the app to update the score. People who previously subscribed to the match, will be notified and see the updated score.
Even though I'm not familiar with backends based on Java, the implementation should be fairly similar to other programming languages.
First of all a few words to REST in general. REST is generally needed, when you need to share information between multiple devices and or users. This seems to be the case here. To implement the REST you are going to need an API of some sorts. Within the web APIs are implemented by webservers answering to certain predefined HTTP Requests.
Thus setting up an API on a web server is the correct way.
Next a few words on databases. A database is generally needed, if you want to store information persistently. This might, or might not be what you are planning to do. If there are just going to be a few matches at the same time and you don't care about persistence of the data, you can use Java to store a collection of match objects in memory. I'm just saying it is possible, not that it is a good idea. Once your server crashes or you run out of memory due to w/e reason, data is going to be lost. (Of course within the actual implementation you want to cache data for current matches in some way and keeping objects in memory is way to do so).
I'd recommend to use a database.
Within the database, you can then store and access information about the matches like the score, which users subscribed, who played, etc.
JSON is just a way to represent the data/objects that will be shared between the server and the client. You can use JSON to encode request and response data/bodies.
The user has to be informed about the updated score. There are two basic ways to do so. Push or Pull. With pull, the client will check for updated scores after fixed intervals or actions. With push, the server will notify the client about changed scores which will cause him to update the information. Since you are planning on doing a live application and using Java anyways, push seems to be the better way to go.
Last but not least let's have a look at a possible implementation using
Webserver (API endpoints + database)
Administrator (keeps score updated)
User (receives updates)
We assume that the server will respond to HTTP Requests (POST#/api/my-endpoint) with JSON-Objects.
Possible flow
1)
First the administrator creates a match
REQUEST
POST # /api/matches
body: team1=someteam&team2=someotherteam
The server now will create a match object and store it in the database. The response will contain information about the object and whether the action was successful.
2)
The user asks for a list of matches
REQUEST
GET # /api/matches/curret
The response will be a JSON object containing a list of current matches.
RESPONSE
{
matches: [
{id: 1, teams:...}, ...
]
}
3)
(If push)
A user subscribes to a match
REQUEST
GET # /api/SOME_MATCH_ID/observe
The user will now be added as an observer for the match. Again, the response contains information about whether the action was successful or not.
4)
The administrator updates a score
REQUEST
UPDATE # /api/SOME_MATCH_ID
body: team1scored...
The score now gets update on the server (in memory/database) and the user will be notified about the updated score.
5)
The user gets the updated score
REQUEST
GET # /api/SOME_MATCH_ID
RESPONSE
... (Updated score in some way)
I am in the beginning stages of planning a web application using ColdFusion and SQL Server 2012.
In researching the pros and cons of using multiple databases (one per customer) vs one large database, for my purposes I have decided multiple databases would be the best approach.
With this in mind I am now wondering the best way to proceed regarding logging clients in. I have two thoughts here:
I could use sub-domains with each one being for a specific client. The sub-domain also being the datasource name.
I could have a single sign on page with the datasource for this client stored in a universal users table.
I like the idea of option 2 best however I am wondering how this may work in the real world. Making each user unique would not be ideal (although I suppose I could make this off of an email address instead of a username).
I was thinking of maybe adding something along the lines of a "company code" that would need to be entered along with the username and password.
I feel like this may be asking too much of clients though.
With all of this said, would you advise going with option 1 or option 2? Would also love to hear any thoughts or ideas that may differ.
Thanks!
If you are expecting to have a large amount of data per client, it may be a good idea to split each client into their own database.
You can create a global database that contains client information, client datasource, settings, etc. for each client and then set the client database in the application.cfc.
This also makes it easier at the end if a client request their data or you would like to remove a client from the system.
I have a django backend set up for user-logins and user-management, along with my entire set of templates which are used by visitors to the site to display html files. However, I am trying to add real-time functionality to my site and I found a perfect library within Node.Js that allows two users to type in a text box and have the text appear on both their screens. Is it possible to merge the two backends?
It's absolutely possible (and sometimes extremely useful) to run multiple back-ends for different purposes. However it opens up a few cans of worms, depending on what kind of rigour your system is expected to have, who's in your team, etc:
State. You'll want session state to be shared between different app servers. The easiest way to do this is to store external session state in a framework-agnostic way. I'd suggest JSON objects in a key/value store and you'll probably benefit from JSON schema.
Domains/routing. You'll need your login cookie to be available to both app servers, which means either a single domain routed by Apache/Nginx or separate subdomains routed via DNS. I'd suggest separate subdomains for the following reason
Websockets. I may be out of date, but to my knowledge neither Apache nor Nginx support proxying of websockets, which means if you want to use that you'll sacrifice the flexibility of using an http server as a app proxy and instead expose Node directly via a subdomain.
Non-specified requirements. Things like monitoring, logging, error notification, build systems, testing, continuous integration/deployment, documentation, etc. all need to be extended to support a new type of component
Skills. You'll have to pay in time or money for the skill-sets required to manage a more complex application architecture
So, my advice would be to think very carefully about whether you need this. There can be a lot of time and thought involved.
Update: There are actually companies springing around who specialise in adding real-time to existing sites. I'm not going to name any names, but if you look for 'real-time' on the add-on marketplace for hosting platforms (e.g. Heroku) then you'll find them.
Update 2: Nginx now has support for Websockets
You can't merge them. You can send messages from Django to Node.Js through some queue system like Reddis.
If you really want to use two backends, you could use a database that is supported by both backends.
Though I would not recommended it.
I need to design and implement a Java web application that can be used by multiple users at the same time. The data that is handled by this application is going to be huge and may take about 5 minutes for a page to display the results(database records).
I had designed this application using HTML, Servlets and JSP. But when two users would try to get the records, only one user was able to view the results while the other faced an error.
I always thought a web application would take care of handling multiple users but this is not the case.
Any insights on this would be highly appreciated.
Thanks.
I always thought a web application would take care of handling multiple users but this is not the case.
They do if they're written correctly. Obviously yours is not. That's all we can tell you unless you give more information, most importantly details of the error shown to the second user.
One possibility is that everything is OK on the web layer but your DB access for the first user causes an exclusive lock so that the second user cannot access the data at the same time. This could be fixed by using non-exclusive read locks. How to do that depends mainly on what DB you're using.
Getting concurrency right requires you to choose the correct tools and use them correctly. It doesn't just happen magically because it's a web app.
What are are using to develop this web-application? If you are developing it in your own way from the start I must say you are trying to re-invent the same wheel which has been already created and enhanced by very solid frameworks.
I suggest you analyze your requirements thoroughly and study some available frameworks. Let them handle the things like multi threading and other aspects in the best possible manner.
Handling multiple request at a time is a container work and as an application developer we have to concentrate how we are handling and processing those requret being forwarded by the container.
I must suggest you to get some insight how web-application work and how request -response cycle happens
I need to be able to access a mySQL database from my iPhone, for both read and write ops. Instead of using MCPKit (due to security and speed considerations), I'd like to access the db through a separate service. The app is iPhone SDK, so I need to get data back in XML form, not as a web page.
I am trying to decide whether to write a Java web service (SOAP) to provide this link, or to just throw together a PHP script on the server side. I can create either solution, but I don't know enough to figure out the advantages/disadvantages of the choice. Please help; thank you!
If you're writing both the client and the server, and performance isn't a significant issue, then the primary remaining consideration is development time.
So, what tools do you have at your disposal? Which platform will allow you to do this with the least amount of work? If it's a toss-up between the two, then pick the one you're most familiar with.