In Codeigniter, the function session->userdata($item) is used to retrieve session data and the definition of this function in Session class is :
function userdata($item)
{
return ( ! isset($this->userdata[$item])) ? FALSE : $this->userdata[$item];
}
Now the problem is this:
Each time a script is executed, a session object is created and the retrieved data is persistent untill end of the script. So if another script for example update session values, new values will be stored in DB, but retrieved data in other session objects are not updated and it makes an obvious inconsistency and inaccuracy in data.
I think it can be a serious problem in many cases.
Is it right or I'm misunderstanding something here? And if
IN codeigniter session object is created during the class initialization and userdata(session values) are updated every time user makes request. You can view whole session object via below piece of code:
print_r($this->session);
This will show you the complete session object with all necessary configurations you have set in your config file for session related variables like:
sess_encrypt_cookie, sess_use_database,sess_expiration ..etc
plus your current session user data. Now when you make next request session values are overridden by the new one or old values are just replaced by the new one. So there is no chance of data duplicacy or inconsistancy. It is recommended to use session table whenever you are saving large amount of data in session.
Related
In angularjs 1.5 I have used local storage to store session related information.
But when I open new tab with some other credentials, initial information is getting erased and getting replaced by the new one, is there any way to prevent this ?
Yes there is, What you are doing is replacing the same key with new data that is why it is getting replaced. What you should be doing is create new 'Key' for each session.
Example
//localStorage.setItem('key', 'value' )
//What you should do is for each login user create a new key
//sessionId can be any id you want for new session, this way you won't overwrite the previous session data
localStorage.setItem(sessionId, loginSessionData);
Since you didn't provide any code sample it's hard to tell what is going on, but i guess when the app starts you set some value to localstorage, so each time you open a new tab you set it again and override the previous value.
All you need to do is check if the value exists in localstorage and if it does do nothing:
if (!localStorage.getItem('myItem')){
localStorage.setItem('myItem', myValue));
}
Using the AuthComponent in CakePHP 3, you can access the currently logged in user in a Controller using $this->Auth->user(). However, this method returns only an array, not a User Entity.
In many places, I have to work with the User Entity of the logged in user, but have to query the UsersTable manually after getting the id from the AuthComponent, which seems quite silly, as the AuthComponent fetches a hydrated User Entity anyway and flattens it to an array. So the User Entity is fetched twice.
Is there a way to get the hydrated User Entity from the AuthComponent instead of an array?
$authUser = $this->Auth->user('id');
if($authUser !== null) {
$authUser = $users->get($authUser);
}
The main reason entities are not stored in the sessions is because there is no guarantee that the auth data is an actual database user. For example, you may be authenticating some credentials from an external system, such as a single sign on in a remote server.
Another reason is that user info can be expected to change from request to request and doing a db lookup on each request is less than ideal.
Finally, people could think that by changing the data in the session entity they would be modifying the user (or modifying the data in the table would refresh the session).
I would suggest just converting your array data to an entity using new User($data) whenever you need an entity.
I'm trying to get an Associated Model (E.g. groups and associated users) from a store with:
Ext.each(this.getView().getSelection()[0].getAssociatedData().users,function(element){
var theuser = myStore.getById(element.id);
theuser.set('deactivated','true');
}
This works for the first 25 Users (id 1-25) however the store is filtered through a pagination plugin. In reason of the filtering with offset and limit the requested id isn't in the local store.
any idea on how to force the store to get the model from remote in case the id isn't available in the local cache?
Or is it anyhow possible to use the data from getAssociatedData, change something and write the record back through the writer proxy?
thx, I really appreciate your help!
The store's getById() method will only return the locally-available records.
If you want to retrieve a model, and you know the id already, you can simply do <model class>.load(id). (If the model is unknown, you can do myStore.getModel().load(id)
Note that the load method returns immediately, but it returns a stub - you'll want to use a callback to process the change to the deactivated field.
In ExtJS5, the Session support will help ensure that the models referred to in both the association store and your myStore object refer to the same model instance.
I'm just getting my head around BackboneJS, but one of the (many) things I'm still struggling with is how exactly the Models Sync up and relate to the serverside DB records.
For example, I have a Model "Dvd", now I change an attribute on the "Dvd" Model, the Name for example, and then I call save(), how exactly does the server side know what DB record to update? Does Backbone hold the DB row ID or something else?
Yes, typically you will set up your Backbone models so that they have database row IDs for any objects you're working with. When one of them is brand new on the client side and not yet saved to the server, it will either have a default or no ID, which doesn't matter since the server will be assigning the ID if and when the initial save transaction succeeds.
Upon saving or updating a model item, Backbone expects the server to reply with some JSON that includes any attributes that have changed since the save or update request was made. In the response to the initial save request, the server informs the client of a newly saved item's row ID (and you can also send along any other information you might need to pass to the client at the same time).
By default, the 'id' attribute of a model object is assumed to be its unique identifier, but backbone lets you change this if you're using a different identifier for the primary key. Just give your model an idAttribute parameter (see the docs for Backbone.Model.extend()) to do that.
Meanwhile, either the urlRoot parameter or a url function can be given to your models to characterize the urls that should be used to send the various ajax requests to the server for a given model.
I am having problems saving database records using Linq in visual studio 2010 and sql server 2008.
My problem is that when I am editing some records I sometimes check the original database record for validation purposes, only the original entry seems to be updated in real time - I.e. it is already exactly the same as the edited record, before I have submitted the changes!
Could anyone suggest an effective method of coping with this? I have tried using a 2nd database connection or a 2nd data repository to call the original record from the db but it appears to be already changed when I debug it.
public void SaveobjectEdit(object objectToEdit)
{
object originalObject = GetobjectById(objectToEdit.Id);
if (originalObject.objectStatus != objectToEdit.objectStatus)
{
originalObject.objectStatus = objectToEdit.objectStatus;
}
SaveChanges();
}
The save changes just calls _db.SubmitChanges(); by the way
Has no one got any ideas for the above question?
I hope I was clear - for validation purposes I would like to compare an original database record with one that I am editing. The problem is that when I edit a record and then attempt to retrieve the original record before saving - the original record is exactly the same as the edited record.
If you're trying to retrieve the original record in code, from the same 'context' using the same access method, then it will contain the updated object. Rather than ask why you're doing this or what you're trying to achieve, I'll instead explain how I understand the data context / object context to work (in a very loose and vague fashion).
The context is something like an in-memory representation of your database, where everything is lazy-loaded. When you instantiate the context you're given an object which represents your data model (of course it may not be a 1-1 representation, and can contain various abstractions). Nothing is loaded into the context until necessary; any queries you write stay as queries until you peer in their results. When you access an item (e.g. GetobjectById(objectToEdit.Id)) the item is loaded into the context from the database and you can get and set its properties at your leisure.
Now, the important part: When you access an item, if it has already been loaded into the context then that in-memory object is returned. The context doesn't care about checking changes made; the changes won't be persisted to the database until you submit, but they remain in memory.
The way to refresh the in-memory objects is to call the Refresh method on the context. Try this test:
using (var db = new MyObjectContext())
{
var item = db.Items.First();
item.Name = "testing this thing";
Console.WriteLine(db.Shifts.First().Name);
db.Refresh(System.Data.Objects.RefreshMode.StoreWins, db.Items);
Console.WriteLine(db.Shifts.First().Name);
}
I believe this pattern makes a lot of sense and I'm not sure it could work any other way. Consider this:
foreach (var item in db.Items)
{
item.Name = "test";
}
Assert(db.Items.All(item => item.Name == "test"));
Would you want the Assert to fail? Should those items be reloaded? I don't believe so. I'm looking at the items in my context, not in the database. I'm not checking whether items in the database have been updated, but instead that I've updated all the items in the context of my code.
This is a good reason why I don't use MyObjectContext db - it is not a 'db' or a database connection. It's a context within which I can change whatever I want, so I name it such: MyObjectContext context.