Combining metadata from multiple sources - asp.net-web-api

In a SPA app using breeze, how would I go about combining metadata from multiple sources for related data so that I can use them in 1 manager on the client. For example, I might have the following
Entity Framework Metadata from WebAPI controller (e.g. Account)
Custom Metadata from DTOs (e.g. Invoices)
Data from a third party service with metadata provided from client side metadata (e.g. Invoice transmission result)
In each case the data has related properties so I might want to be able to use Account.Transactions.TransmissionResults
UPDATE
I have tried several ways of getting this to work but to no avail. From Jay's answer, it is not possible at present to update the metadata from the server once it has been retrieved, so if and until that changes (see breeze user voice issue) I am left with one of the following approaches
1 Retrieve metadata from the server from Entity Framework and add metadata on the client to add extra entities. This worked to a degree but I could not add navigation properties from entity types added on the client to entity types retrieved from the server because I cannot add the foreign key association to the entity retrieved from the server, again back to the need to modifying metadata after it has been retrieved.
2 Write the complete metadata by hand, which will work but makes maintainability that much harder and seems wrong to be manually writing mostly the same code that the designer would write.
3 Generate most of the code from Entity Framework as described in the docs and then update it afterwards to add in the custom entities. Again similar issues than with option 2, it seems hacky.
Anyone else tried something similar? Is there something I am missing, which I could be, I've only started with breeze and js.
Thanks

A breeze EntityManager can have metadata from any number of DataService endpoints, and you can manually add metadata (new EntityTypes) on the client at any point. The only current restriction is that once you have metadata from a specific service, you can't change it. ( We are considering reviewing the last restriction).
So the question is, what are you trying to do that you can't right now?

Related

AsyncCrudAppService Breaks Swagger When Providing TCreateInput and TUpdateInput

I recently downloaded a Single Page Web Application (Angular) from https://aspnetboilerplate.com/Templates using 3.x target version.
I just simply added a few entities and then started to follow the steps on this page https://aspnetboilerplate.com/Pages/Documents/Application-Services
Things do work well for me to Get, List, Update, and Delete entities when my app service class is just inheriting AsyncCrudAppService<Entities.PhoneBook, PhoneBookDto, long, GetAllPhoneBooksInput>, however when it is inheriting AsyncCrudAppService<Entities.PhoneBook, PhoneBookDto, long, GetAllPhoneBooksInput, CreatePhoneBookInput, and UpdatePhoneBookInput> the swagger definition will no longer load.
GitHub Repo: https://github.com/woodman231/MyPhoneBooks
(which currently does not work and will not load Swagger page).
I can get the swagger page to load by removing CreatePhoneBookInput and UpdatePhoneBookInput from
https://github.com/woodman231/MyPhoneBooks/blob/main/aspnet-core/src/MyPhoneBooks.Application/SimpleCrudAppServices/ISimplePhoneBookCrudAppService.cs#L9
and
https://github.com/woodman231/MyPhoneBooks/blob/main/aspnet-core/src/MyPhoneBooks.Application/SimpleCrudAppServices/SimplePhoneBookCrudAppService.cs#L14
However, again I am still unable to create entities using this default implementation. Any ideas?
I have cloned your repo and run it and I figured out the error, first as I tell you in comments I verified the text log, and it said the next:
System.InvalidOperationException: Can't use schemaId "$CreatePhoneBookInput" for type "$MyPhoneBooks.SimpleCrudAppServices.Dtos.CreatePhoneBookInput". The same schemaId is already used for type "$MyPhoneBooks.PhoneBooks.Dtos.CreatePhoneBookInput"
What happenig is that you have these two classes UpdatePhoneBookInput, CreatePhoneBookInput repeated in SanokeCrudAppServices\Dtos and PhoneBooks\Dtos
You have the classes in both folders with same exact name, and thats the problem, if you change the name in whatever place the swagger definition will load without errors, I have do it like this and everything works fine!
Change the name in one of the places, and all will be working fine
Personally I don't like to use a different Dto for Create and Update for me is easier to user just one Dto for all.
Ok I figured it out. I had also made a DIY AppService and some of the DTO Class Names associated with the DIY App Service clashed with the DTO Class Names associated with the Automated Service. It was acceptable in .NET since they were in different name spaces but once the swagger definition was configured I assume that there was multiple instances of the same DTO Defition. I checked the AbpLogs table but they didn't give me much details as to the specifics of the internal server error while loading the definition. It sure would have been useful to know that.

accessing table metadata from embedded Teiid server

I have embedded Teiid 12.3 in a Spring Boot application. I want to get into the metadata of my VDB in order to generate a diagram using graphviz-java. I assume that if I have a org.teiid.metadata.Table object, I can call getIncomingObjects() to get references to tables that table depends on. I just can't figure out how to navigate from the EmbeddedServer to the Table objects.
I looked into using the administration API available via EmbeddedServer.getAdmin(). From there, I can call getVDBs(), and from there I can navigate down to getModels(), but below that level there is only the model source via getSourceMetadataText(). I also tried subclassing EmbeddedServer to make getVDBRepository() public. I can call getVDBRepository()*.getModels(), but it returns the same Model objects only get me access to the source definition of the models, not the runtime metadata model.
I tried getVDBRepository().getSystemStore() and VDBRepository.getODBCStore(), but those MetadataStores are not for the VDB I have deployed.
I haven't found any examples by Google, Teeid JIRA, Teiid forum, or StackOverflow to help me.
Take look at [1] the getSchema method on Admin API, this method returns the string form of the metadata, however you can grab Schema object for object form. If you do not want that way, Teiid also exposes system catalog using many SYS tables, you can issue SQL queries to grab the metadata of schemas and schema items in a VDB. One for internal access, another is from external access.
BTW one of users created a dependency diagram tool that may be useful if you are trying to do something similar. See [2]. Let me know if you interested in pushing that further.
[1] https://github.com/teiid/teiid/blob/master/runtime/src/main/java/org/teiid/runtime/EmbeddedAdminImpl.java#L544-L557
[2] https://github.com/teiid/metadata-catalog-ui

ms crm 2015 - set id of entities from jscript onsave

I need to sync entities from Ms Dynamics Crm 2015 - On Premise to my 3rd party application, for this I have set a JavaScript function on the OnSave event of the Entites( eg. account) I can access all of the attributes and send them to my webservice, but the Id (GuId) of the entity!
how can I access the Id (or set it manually) on this event?!
Xrm.Page.getAttribute("accountid") or Xrm.Page.getAttribute("id") both return null, so I can not setValue using them.
Also Xrm.Page.data.entity.getId() returns "" which is probably logical, since Object has not been inserted in the db yet, this is the reason which makes inserting a runtime generated guid for the entety seems doable !
P.S.
I know I can do same thing with plugins, which I have gone through, but the problem there is that when I register my plugin for Update message it gets called a lot of times, (mostly when it has been set for invoice), this is the reason that made me go with the JScript, since the OnSave Event seems more logical than the Update Message of the plugin
As you already found out, records which have not yet been saved have no ID. That's by design (and obvious).
Also, IDs being PKs in the database, they are handled by the system and cannot be touched or hand-crafted.
Your best bet to keep a similar behavior would be a Post-Operation Create plugin living outside the sandbox (Isolation mode: None).
Another good option would be to pull data instead of pushing it: the 3rd party application can periodically fetch new records through any of the exposed APIs (REST, SOAP, SDK ... there are many options).

In WebAPI Breeze implementation, can I avoid exposing Metadata function?

Opening Metadata function using Breeze via API is actually equivalent of exposing the underlying database schema.
Is there a way to avoid opening up metadata api call? I tried not exposing it as suggested. I got the following error
Query failed Metadata query failed for: /breeze/NorthWind/Metadata; The requested resource does not support http method 'GET'.
What is the right way of avoiding exposing Breeze Metadata calls.
In addition to obtaining metadata via an API, there are another couple of approaches you could consider:
Load metadata from a script. With this approach, you embed the metadata in a script. After loading the script, the Breeze EntityManager can be initialized using the metadata from the script rather than calling an API. I've found this approach quite useful for unit testing when a dependency on accessing a server is undesirable. See Load metadata from script for more details.
Build metadata with hand-written Javascript code to configure it. You probably wouldn't want to do this for a complex data model that you have already defined in Entity Framework, but it can be useful if that isn't a constraint. See Metadata by hand for discussion on this approach.
Once you do have metadata, you can export and import the metadata (such as to the browser's window.localStorage area) using MetadataStore.exportMetadata and MetadataStore.importMetadata respectively.
You need to provide some sort of metadata for Breeze to work. If you do not want to expose your DB structure, either you have to manually change the metadata generated, or have another layer in between your DB entities and the data classes you want to expose. You can generate the metadata of the intermediate layer by data annotations.

Tracking Changes Object Changes

I wanted to get your opinions on the easiest way to track changes that users make when they do CRUD events. I am working on a system where the users are less interested on permissions, but really want to have a sophisticated log of what changes a user made. I am using ASP.NET MVC 3, EF, and NLog.
Any advice is greatly appreciated :)
Steve
I use a convention based approach. Each entity has an associated audit entity which includes all properties from the base entity plus information on the change, including whether it was successful or not. I override the SaveChanges method on the DB context. For each entity being changed it creates an audit entity from it holding the new values. It attempts to save the changes, then uses a separate, auditing context to save each of the audited entities with the results of the save operation. I use an injected utility in the data context to get access to the current user (via HttpContext.Current for web, via the Environment.User for non-web) when constructing the audit entities.
I blogged about an earlier version of this for LINQ to SQL at http://farm-fresh-code.blogspot.com/2009/05/auditing-inserts-and-updates-using-linq.html. You should be able to get the basic idea from that.

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