I'd like modify an existing TYPO3 extension by adding extbase domain models while keeping the existing database structure.
There are two database tables: location and person, and they have no direct connection - the old code simply related them by their pid column. If you want the location for a person, you'd have to select the location that has the same pid.
Now I would like to be able to load the location from the person's domain model class, but extbase is not able to figure out how to load it automatically.
What do I have to do to override/customize extbase's relation loading behavior, so that I can access the location object via $person.location, while benefiting from extbase's automatic caching and eager loading?
(When implementing getLocation() in the Person class myself, extbase would not load the location automatically in the first SQL query. Also, I'd have to implementthe local caching myself, so that repeated accesses to getLocation() would not lead to duplicated database accesses.)
If you can't change the extension yourself, I would go for using https://extensions.typo3.org/extension/extender and add the additional property + getters.
Additionally you need to extend the TCA to let editors select the relation in the backend.
Related
Since TYPO3 uses doctrine it is possible to use tables from multiple databases in one instance (with some restrictions like no joins).
But what is possible at all?
At the moment I need two external tables for an extension and instead of using them directly I import them to work locally as usual. But the importing has some draw backs.
Draw backs I can accept:
the data is not live (changes to the external tables are imported later)
the data is read only (changes are done externally anyway)
For importing I use ext:external_import but there are some problems as not all data can be imported in a single run, and then there are errors (e.g. there are reports about duplicate keys, alas there are no duplicate keys in the external tables)
On the other hand I doubt I can use the external tables directly as they have not the usual TYPO3 structure (fields: 'uid', 'pid', 'tstamp', ...). (Maybe they can be mapped in a view?) (of course in the tables I import the data into these fields exist)
Also external changes may be unnoticed and cached content does not reflect current data. In my case that would be a minor problem, as we currently already have no 'live' data, but this needs to be cleaned regularly for cache and for the search index (solr).
What are possible solutions? ? (do they depend on the TYPO3 version?)
What are your experiences?
EDIT:
While trying to realize it considering the given answers more doubts appear:
the tables are readonly (as they are changed from outside):
How do I declare it to TYPO3?
the tables does not follow the usual name rules, especially one table is named sys_category which in this way conflicts with the TYPO3 table sys_category.
Can I build a mapping inside of TYPO3?
Can I build a view from TYPO3 for renaming tables and fields?
like:
CREATE View tx_myext_category
SELECT id as uid, name as title, ...
FROM databasename.sys_category;
Yes, you can fetch data directly from other databases/tables. Of course it highly depends on the usecases and the data you get:
It works fine to read/write data by using the queryBuilder and all the APIs you know from https://docs.typo3.org/m/typo3/reference-coreapi/master/en-us/ApiOverview/Database/Index.html like ConnectionPool, QueryBuilder
If you want to show the data in the formengine, e.g. list module, you will need to have the minimum columns like uid, pid and a valid TCA as well.
From my experience, the mapping mechanism only works if the external table has a almost similar structure as TYPO3 tables. You need at least a uid field on the external side. This cannot be mapped! A missing pid field could be managed with on the TYPO3 side, also crdate or tstamp if needed. Just fill the local data array with the values TYPO3 needs.
Problems arise if you have relations to deal with. Many external systems have other ways to handle relations. You could run into many problems if you try to rely only on the mapping mechanism.
Other problems are fields with date format. Most external tables in the MS world use another format as the unixtime.
If you run into problems with the mapping mechanism you can switch to the TYPO3 queryBuilder. This is a powerful fallback. I experienced problems only with a special type of JOIN statements.
But with the TYPO3 queryBuilder you are on your own. You place instances of the queryBuilder code in the repository and add your model code as usual: thus you can continue to work with Fluid in the frontend as you are used to.
ANSWER TO EDIT:
With the TYPO3 queryBuilder readonly tables aren't a problem. Just don't implement the setter classes in your models.
With TYPO3 queryBuilder you can call any external table with any name. You have full control over the output data in your repository because the mapping is handled inside of it.
As far as I know, there is no way to create SQL views in TYPO3 up to v9, neither with the DBAL mapping mechanism nor with the TYPO3. queryBuilder.
In a JHipster based project, we need to selectively filter out certain columns based on role/user logged in. All users will be able to view/modify most of the columns, but only some privileged users will be able to view/modify certain secure fields/columns.
It looks like the only option to get this done is using EntityListeners. I can use an EntityListener and mask a certain column during PostLoad event. Say for example, I mask the column my_secure_column with XXX and display to the user.
User then changes some other fields/columns (that he has access to) and submits the form. Do I have to again trap the partially filled in entity in PreUpdate event, get the original value for my_secure_column from database and set it before persisting?
All this seems inefficient. Scoured several hours but couldn't find a specific implementation that best suits this use case.
Edit 1: This looks like a first step to achieving this in a slightly better way. Updating Entities with Update Query in Spring Data JPA
I could use specific partial updates like updateAsUserRole, updateAsManagerRole, etc., instead of persisting the whole entity all the time.
#Repository
public interface CompanyRepository extends JpaRepository<Company, Integer> {
#Modifying(clearAutomatically = true)
#Query("UPDATE Company c SET c.address = :address WHERE c.id = :companyId")
int updateAddress(#Param("companyId") int companyId, #Param("address") String address);
}
Column based security is not an easy problem to solve, and especially in combination with JPA.
Ideally you like to avoid even loading the columns, but since you are selecting entities this is not possible by default, so you have to remove the restricted content by overriding the value after load.
As an alternative you can create a view bean (POJO) and then use JPQL Constructor Expression. Personally I would use CriteriaBuilder. construct() instead of concatenating a JPQL query, but same principle.
With regards to updating the data, the UI should of cause not allow the editing of restricted fields. However you still have to validate on the backend, and I would recommend that you check if the column was modify before calling JPA. Typically you have the modifications in a DTO and would need to load the Entity anyway, if a restricted column was modified, you would send an error back. This way you only call JPA after the security has been checked.
Normally, we have for each attribute of our persistence class a field in the database. Those we can save back by just start a transanction, make some changes and then end our transanction. (like they did here)
But now I have a more complex object, going over two tables, (im my case an additional text table), so I add an attribute title, and in the init( )I pull the information from the database.
Now how can I save this information back into the database? The persistence service does not know where to save that title.
I did some research and found this Thread on SCN, where the root problem (Creating a persistent class for a table with an addidional texttable) is described.
Im currently working in a team that uses EF as the ORM of choice.
We have a common project that contains many EDMX files.
The reason for this is to keep the EDMX files small and manageable while also allowing them to focus on a conceptual set of tables on the database.
Eg
Orders.edmx
Users.edmx
Trades.edmx
These all point to a different set of tables on the same db.
I now need to add the user table to the Trade.edmx file. Since the user table is already in the user.edmx file, this creates the same User type twice under a different namespace which means I would need 2 UserRepository objects.
Common.data.trade.User
Common.data.users.User
Is there a way of avoiding 2 repository objects for the same table?
Any suggestions would be greatly appreciated
If you are using POCO generator you can update template for Trades.edmx to not generate new User class and its context template to use User class from Users namespace. EF matches POCO classes with entities in designer only by the class name (namespace is omitted) so it will work.
The disadvantage is that you have User entity in two mapping files and you must update it in both files or your application throw exception at runtime.
The reason for this problem is your architecture - at the beginning you wanted separated models but know you want to combine entities from different models. Those are contradicting requirements. Either use separated model where Trade knows only userID without any navigation property (like if it is defined in another database) or move all entities to single EDMX to support your new requirements.
I have been working with the Entity Framework + Self-Tracking entities, and came out with a problem:
Is there any way to determine when an entity has been changed??
For example: If you have an entity User with two fields: Name and Password, you can know if an User instance has been changed making:
<user>.ChangeTracker.State != ObjectState.Unchanged;
My problem is when the User has a Person, and the person has a field Email. I want that if the email field is changed, then the corresponding User is changed too.
I have been trying with methods such as: <user>.StartTrackingAll(); but this does not work with navigation properties (or maybe i am doing something wrong). Some help about this can be found here.
Remember that the Self tracking entities are autogenerated via T4 templates, so the clases can't be modified.
First when wanting to know if any entity in a so-called object graph has changed you can recurse through all entities contained in trackable collections or one-to-one navigation properties of a root entity (user in your case). This way you can know if a person inside the root entity has changed. This is actually how I check complex object graphs for any changes in any of the contained entities. But also for checking out if any of these entities have critical validation errors (so the user can't persist them yet).
Remember that the Self tracking entities are autogenerated via T4 templates, so the clases can't be modified.
Not true. First of all you can modify the T4 template to generate more (complex) code to achieve the things you want. And second, it generates partial classes which can easily be extended with custom (non-generated) code.
If you change the email in the Person instance only that instance is correctly marked as modified. That is absolutely correct behaviour. What do you expect? Do you expect that change to property in related entity will propagate changed state to relations? That would make STEs completely useless because any single change to entity graph would make all entities in the graph modified and each this modification causes additional roundtrip to the database.
If you want to set User as modified when you are changing email simply create some method or handle some event and call person.User.MarkAsModified()