I am looking for application development in such a way that it should work whether the user has an Internet connection or not.
I am working on a mobile PHP/MySQL based application. Sometimes an Internet connection is not available at the required place. I want to keep the database in a buffer and want to update it as it gets connected with the Internet, so that the application can work without any interruptions.
Depending on how much data you need to be persistent on the client's machine, you might be able to use cookies to save this data.
Here is a simple example of storing some information in cookies
// set the cookies
setcookie("someInfo[key1]", "4815162342");
setcookie("anotherValue", "foobar");
Now, after you have set the cookie, you'll be able to retrieve the data on other pages from the same domain.
echo $_COOKIE['anotherValue'];
// prints "foobar"
print_r($_COOKIE['someInfo']);
// Array(
// 'key1'=>"4815162342"
// )
Reference -
PHP Cookies
setcookie()
You can use Web Storage
Web storage and DOM storage (document object model) are web application software methods and protocols used for storing data in a web browser. Web storage supports persistent data storage, similar to cookies but with a greatly enhanced capacity and no information stored in the HTTP request header. There are two main web storage types: local storage and session storage, behaving similarly to persistent cookies and session cookies respectively.
But that's about it in terms of reasonable data storage on the client
Also see
HTML5 Web Storage vs Cookies
Best way to synchronize local HTML5 DB (WebSQL Storage, SQLite) with a server (2 way sync)
Related
I am working on a service that sits between a client and an API. A client user does API requests via my service. The API requires several user cookies to be set to authenticate the user and allow requests. The client cannot store cookies, so I am storing all the cookies on AWS EFS. The service is written in PHP and API requests are done using cURL. Cookie handling is done using cURL's CURLOPT_COOKIEFILE and CURLOPT_COOKIEJAR.
The problem is that sometimes the cookie file gets overwritten instead of appended to or updated, leading to API requests failing. I am still trying to find the cause of this, but I am considering saving the cookies to the database instead of in a file. Obviously this will lead to an increased database load, but I cannot think of any other disadvantages. Are there any?
I am working on an PHP API application that will work an different domains (and hosted on different servers) that need to share user session. Let's say api.a.com and api.b.com.
Back end side, for me, storing session data using a session id key that can be fetch from multiple domain is the easy part.
My main concern is sending session id to both api.a.com and api.b.com. Native PHP session uses cookies to send session id for each request. Having different top level domain, the cookies will not be sent to all domains (unless I explicitly use Javascript to extract it and send it as a request header).
I thought about storing the session id inside the the Json Web Token data sent to the server, but somehow, it feels wrong.
Any thoughts on this?
Use a memcache server. PHP supports saving sessions in memcache.
With Amazon, I have a load balancer front with Linux instances, each connected to memcache.
Then I have a completely different EB application and domain that accesses the same memcache and pulls real time stats, so it's pretty easy to setup access to the same memcache server or cluster from different applications.
Note there's a difference between "memcache" and "memcached" -- either can be used, but they're different servers!
Use a memcache server. PHP supports saving sessions in memcache or mysql.
then use sessionid by http transport.
`
$sid = $_REQUEST['sid'];// receive sessionid
session_start();
session_id($sid); //reset current sessionid by $sid
var_dump($_SESSION["A_DOMAIN_SESSION"]);
var_dump($_SESSION["B_DOMAIN_SESSION"]);
?>`
Current scenario :
There is a webservice (build in php/mysql). User filled data is stored on a remote server.
Issue is user has extremely bad internet connection, webservice is down most of the time. Is there a way to store data locally and sync it when internet is available?
Please note, user might not have database installed on his machine also there is no localserver to work with.
Even if user had some type of RDBMS installed on the box, you probably wouldn't have any way to communicate with it. You can use the HTML 5 Storage API, but it will not solve the connection issues.
And since localStorage (which you probably would use) is available directly only from JavaScript, you would have to make a complicated and fully functional JS application to utilize it.
Note: based on your profile, I would estimate that your JavaScript skills would not be adequate for such task.
If your target audience is mobile users, then you have another alternative: create a native application.
You would still be able to use HTML for the interface (using built in web browser components). But it also would let you have SQLite DB and file storage available on the mobile device, where you can cache the necessary data.
look at the features in HTML 5 for local storage
Typically I would go with IndexDB and then push the local data to the server once the connection is back
http://diveintohtml5.info/storage.html - Should give you a brief about the features and implementation.
In PHP, you manage the Session on the server... accessing any of the session properties there on the server along side your web application.
How does this translate to an iPhone App? If I'm connection to web services (PHP, ColdFusion), where should I be managing sessions? Or does it work differently in this scenario?
Assuming your PHP code use cookies to track the active session (as opposed to, say, a session id request parameter), NSURLConnection handles cookies for you without any extra work, and it should work the same way it does inside a browser.
I want to find each LAN connected computer separately. I am fetching ip address but i am assuming if many computers are connected to LAN they may give same ip.How can i differentiate all computers separately in php ?
Just use Sessions and Cockies.
easiest and best way: use phps session-management - every client is given an id, stored in a cookie (if enabled) or given as a get-variable on every link and form. (alternatively you could set a cookie on your own)
identifying every client by ip is a bad idea and won't work. clients that use the same router will have the same ip's - clients connected through a proxy-pool could have another ip with every page load.
EDIT: if you need a solution that can't be manipulated by the client in an easy way, try to do a combination of those, using all that are supported by the clients browser and compare them on each page-load:
"normal" HTTP Cookies
Local Shared Objects (Flash Cookies)
Storing cookies in RGB values of auto-generated, force-cached PNGs using HTML5 Canvas tag to read pixels (cookies) back out
Storing cookies in and reading out Web History
Storing cookies in HTTP ETags
Internet Explorer userData storage
HTML5 Session Storage
HTML5 Local Storage
HTML5 Global Storage
HTML5 Database Storage via SQLite
You can't. The only thing would be to use sessions (i.e. cookies) to differentiate them, but that's not a safe way.