This is great for simple solutions where EF context is tightly coupled to API. What about solutions that have a core project with domain models, services and repositories and where every piece is resolved dynamically when the solution is running?
Amazing, thanks a lot. that was amazing intro, now I need to figure out how to integrate it with ASPCore Policy Based Authorization, to control Entity extending and other OData Features..
@@aah134-K if you materialize your data coming from EF as a list then it runs in memory, if you run on an IQueryable DataSet in EF then it runs on the database.
great lternative to the current trend of GraphQL, and i really like this approach , with graphQl you overfetch from the db nd filter on the server, this uses Entity framework to filter in the database
Nice video! 2 questions. 1. If I have a response like this { id:"123", "metadata": { "branch": "master" } }, { id:"1234", "metadata": { "branch": "master" } }, { id:"1235", "metadata": { "branch": "master1" } }, how do I $select just the branch property? 2. How can i select only the distinct branches? (master and master1 in this case?)
If you notice, the response without the $expand and $filter the API follows the camelCase and once you add the $filter or $expand it omits the default camelCase.
I've seen a company that used OData in a large size application. And I only have one advise about it: OData or even GraphQL are good if you can chuck your application to small size services or you will close the door of updating your project to newer technolgies forever. Then the life will be so hard! :D
$count is not working with endpoints.EnableDependencyInjection();, it works without and adding routeBuilder.MapODataServiceRoute("ODataRoute", "odata", GetEdmModel(app.ApplicationServices)); in .UseMvc(). Any suggestion how $count work with endpoints.EnableDependencyInjection()?
Really interesting. Are there any libraries which make generating Typescript clients possible? I'm also curious if OData can be used for add/update/delete operations. I guess I'll check out the docs!
I wonder if this implementation is paving the way for support for GraphQL, or will it always be a divergent solution? At minimum, definitely a promising addition for standard APIs.
OData actually existed before GraphQL, in fact OData is a lot more powerful than GraphQL check out the comparison here: www.progress.com/blogs/rest-api-industry-debate-odata-vs-graphql-vs-ords
Hassan - First of all, a really cool demo. Is it possible to use the above with a return type as HttpResponseMessage for my Get action (.NET Core 2.0 - Web API)?
Hey. Is any one seen a recent example how to unit test a controller with ODataQueryOptions filter. I am having a trouble to create it of mock it. All example which i found do not work with the .net 5. Thanks
If you're having an api which executes an specific store procedure for that specific endpoint, then you can change the output by altering the store procedure right? This can be done without having to build and release an new version of the api that now needs a new functionality to the routebuilder.
Yup, that's exactly what I meant, in fact it's even simpler in ASP.NET Web API with .NET Framework, you still gonna have to add OData service, but then you don't have to do the dependency injection part, just add [EnableQuery] to your controller and you should be good to go!
I didn't test it yet, but here is an article from Hassan about OData in asp.net core 3.1 devblogs.microsoft.com/odata/experimenting-with-odata-in-asp-net-core-3-1/
Hi @ Hassan Habib! Great video and explanation! Thank you! I have a question: to practice, I'm play around Chinook databases (do you know?), and "expand" don't work for me, using it like you in your video. The result json show the value items like [ ]. The relation on databases through foreing key, indexes, etc are fine. Summarizing, it does not show the values tied by navigation properties. Please, can you give me any clue that may be failing? Thanks in advance!
Those 4 lines of code did work in .net core 3.1 . I have to do other config changes as well. Pls update this video with latest .net core version at least 3.1 onwards
Thanks guys amazing demo. But I have one question which I am having a hard time to figure out: is it possible to have both the existing WebAPI and the OData service leaving side by side but to access it with a different prefix like this ? api/Students -> WebAPI odata/Students -> OData I am using .NET 6 / AspnetCore.OData 8
Is there some possibility with the Expand feature to expand to only one level of relationship and not unlimited levels. This will prevent the user to query the whole database.
if a want to have this automatically for every table in my database how I could achieve this without using Entity Framework and map every table manually?
Isn´t OData also about the format, not only how to query the data? Does this also comes with the ASP.NET Core OData Package, how many lines of code would it took to add that? :)
That is exactly what im asking to myself, also i just asked if there is a way to pass the filter options to an underliying layer like a Service Layer to perform the filtering in that layer and not in the controller
Très belle démonstration d'OData, Merci. J'aurai bien aimé savoir comment et surtout à quelle moment les données sont traités (filtre, select,... ) Est ce que c'est vraiment au moment de l'exécution de la requête dans la base de données où une fois remontée, mais ça reste en mémoire côté serveur ? Merci beaucoup
When I download the example and run it, it brings back the student and the school when I just request students.I thought you would only get students and if you did expand=School then you would get school info? The sample code doesn't behave like the video.
It depends on the return type, if your controller method is returning a IEnumerable it will perform differently than if it was returning IQueryable. if it's IQueryable OData will perform the search on the database via EF, if it's IEnumerable it will perform the query on the returned results. hope this helps.
@@HassanHabib This is awesome, because I guess most of ASP.NET Core APIs return IEnumerables from the injected services in the controllers. If you only need 4 lines of code to do all of this, it's f*cking magic! I would like to know how performance is affected with OData, but so far it's quite impressive. Thank you guys, loving all your stuff you are doing and I really hope .NET Core 3 will be a boom in the Software Development world.
So... it is basically method interceptor / middleware.. right? Exposing IQueryable is good only for pretty small applications (RAD), because it is leaky abstraction - even with queryable mapping. This is mapping Querystring -> LINQ expression. Despite i am big critic of GraphQL/ ODATA because of their low usability in real big and performant applications i liek this idea, because it is easy to use and cool transfer-size optimizations. @hassan how does the expand work without EF and .include() extension method? Just ignored? or you can modify mapping of that via configurations?
Yes, here's how to do it: devblogs.microsoft.com/odata/experimenting-with-odata-in-asp-net-core-3-1/ and here as well: devblogs.microsoft.com/odata/enabling-endpoint-routing-in-odata/
This looks interesting. I was trying to add routeBuilder to - app.UseWebApi() ( my app uses this). But I am not able to pass the routeBuilder predicate to this. Can someone help me out please?
@@HassanHabib In Startup Configure(IAppBuilder) -> i am using app.UseWebApi(config) instead of UseMvc. And UseWebApi does not have routebuilder as argument. Can we somehow make this work with webapi as well?
@@sandyhills12 I see. if you're okay with going to 6 lines of code instead of 4 - you can do this: gist.github.com/hassanhabib/a63297a55e802157b353525c9d420363
How did you came out of this error "IServiceCollection' does not contain a definition for 'AddOData' and no accessible extension method 'AddOData' accepting a first argument of type 'IServiceCollection' could be found (are you missing a using directive or an assembly reference?)" P.S: I am using the same directive as you used. i.e. using Microsoft.AspNet.OData.Extensions; please help me.
@@HassanHabib I figured it out. Thanks. I was using .net core for OData and we need other nuget package i.e. .netcore package to install and then do the samething.
Use a prefix for field names doesn't follow C# naming conventions/guidelines, this was a practice that was carried over from C++, here's the coding guideline reference: docs.microsoft.com/en-us/dotnet/standard/design-guidelines/names-of-type-members This also is a good reference: docs.microsoft.com/en-us/dotnet/standard/design-guidelines/general-naming-conventions
Hi. I hava a question. Is routeBuilder.EnableDependencyInjection(); required? As far as I know we can already use DI in controllers without writing this.
@@HassanHabib my question isn't clear. Let me try it again. If the filter has been enabled via Startup.cs, can it be required per endpoint. In the case of api/Students, filter must be supplied, else it'll throw an error. Is that possible?
I see what you're saying, yes you can make it per endpoint by passing a paramter through the [EnableQuery()] annotation that I used in the demo, for instance you can say: [EnableQuery(AllowedQueryOptions = Microsoft.AspNet.OData.Query.AllowedQueryOptions.Expand)] so this way you're only allowing expand but not anything else, there are more things you can do with the EnableQuery annotation to do a per-endpoint control work, does that answer your question?
@@HassanHabib Yes, you definitely did. Thank you. This will be really nice. This means that even though an IQueryable must be returned in order to run the query in the DB, it can prevent getting unfiltered data by requiring the endpoint to supply a filter. Cool stuff. 👍
Well, if you want the client-side capability more than service end-point can provide, then, in essence, you need to write SQL type query. To do that, you need to know the data schema of the source system. If you are going to that direction, then I would question the whole idea of the service concept and service encapsulation.
Nice explanation by JSON Momoa!
😂😂😂
HAHAHAHAHAHA. Thank you. I haven't laughed that hard in a while :)
LOL
😂
There are two types of developers, a LOT of stickers or NO stickers
Truer words have never been spoken.
Hahah! :)
I have 3 stickers on my laptop.
@Sharty Waffles Sure. That's why Jeremy is MVP and you're not.
@Sharty Waffles I believe you they're experts. But I don't believe they got there by not sticking anything to their laptops.
Who needs GraphQL when you have OData ? Wonderful! 🙌
I always love Remote Code Execution
This is great for simple solutions where EF context is tightly coupled to API. What about solutions that have a core project with domain models, services and repositories and where every piece is resolved dynamically when the solution is running?
This is a great way to explain OData. Loved the grocery store analogy. thanks.
Thanks, Hassan and Jeremy for such a nice intro.
I love when standards are open and powerful.
Amazing, thanks a lot. that was amazing intro, now I need to figure out how to integrate it with ASPCore Policy Based Authorization, to control Entity extending and other OData Features..
Thanks for making OData super easy to implement with core! Can’t wait to add additional “4 Lines of Code” to all my API projects. 👍🏻
Hassan, you're a legend - this is exactly what I was looking for!
Thank you Brendan, I think the legends are the visionaries and engineers behind this technology, I'm just trying to bring their amazing work to light.
I have a question,
Does that Odata operations happening directly on Database OR it's happening afterwards on the result set??
If your return type is an IQueryable it runs on the database.
medium.com/@ibrahimozgon/asp-net-core-odata-query-database-over-url-820624beef92
@@HassanHabib ya habib
How about if it is entity framework?
@@aah134-K if you materialize your data coming from EF as a list then it runs in memory, if you run on an IQueryable DataSet in EF then it runs on the database.
@@HassanHabib I did it and the SQL intercepted its a full SQL. This is my github, if you want to see: github.com/odairto/ODataEF
This got to be the best video I’ve seen while working in IT. Thank you 😊
Thank you for watching :-)
Is there a way to inject the OData filtering capabilities outside the Controller? Like in a Service layer perhaps?
Great demo 👍👏, worth every second
Very well explained, thanks
Great, thank you Hassan!
Great tutorial! Thanks a lot!
great lternative to the current trend of GraphQL, and i really like this approach , with graphQl you overfetch from the db nd filter on the server, this uses Entity framework to filter in the database
You misunderstood GraphQL. You can also use the Entity Framework to filter in the DB.
@@marcel830 sure, but you have to spicify the queries that will apply those filters, then you loose the benefict over rest
Magic:) Thank you for this demo.
Nice video! 2 questions.
1. If I have a response like this
{
id:"123",
"metadata": {
"branch": "master"
}
},
{
id:"1234",
"metadata": {
"branch": "master"
}
},
{
id:"1235",
"metadata": {
"branch": "master1"
}
},
how do I $select just the branch property?
2. How can i select only the distinct branches? (master and master1 in this case?)
If you notice, the response without the $expand and $filter the API follows the camelCase and once you add the $filter or $expand it omits the default camelCase.
I've seen a company that used OData in a large size application. And I only have one advise about it:
OData or even GraphQL are good if you can chuck your application to small size services or you will close the door of updating your project to newer technolgies forever. Then the life will be so hard! :D
What reference is being used that is not part of the "4 lines" of code?
$count is not working with endpoints.EnableDependencyInjection();, it works without and adding routeBuilder.MapODataServiceRoute("ODataRoute", "odata", GetEdmModel(app.ApplicationServices)); in .UseMvc(). Any suggestion how $count work with endpoints.EnableDependencyInjection()?
Really interesting. Are there any libraries which make generating Typescript clients possible? I'm also curious if OData can be used for add/update/delete operations. I guess I'll check out the docs!
Of course, we will be discussing this in detail in an upcoming videos.
Wow !!! So you can code and be the best football player in the world 🤣🤣🤣🤣🤣
Two great guys.
Nicely explained..
Awesome..Thanks a lot!
I wonder if this implementation is paving the way for support for GraphQL, or will it always be a divergent solution? At minimum, definitely a promising addition for standard APIs.
OData actually existed before GraphQL, in fact OData is a lot more powerful than GraphQL check out the comparison here:
www.progress.com/blogs/rest-api-industry-debate-odata-vs-graphql-vs-ords
Hassan - First of all, a really cool demo.
Is it possible to use the above with a return type as HttpResponseMessage for my Get action (.NET Core 2.0 - Web API)?
That's an amazing capability, good to know :)
Hey. Is any one seen a recent example how to unit test a controller with ODataQueryOptions filter. I am having a trouble to create it of mock it. All example which i found do not work with the .net 5. Thanks
If you're having an api which executes an specific store procedure for that specific endpoint, then you can change the output by altering the store procedure right? This can be done without having to build and release an new version of the api that now needs a new functionality to the routebuilder.
The end of video mention it works with Classic ASP.NET, I assume that's ASP.NET WebAPI .NET Framework? Is there an example setting that up?
Yup, that's exactly what I meant, in fact it's even simpler in ASP.NET Web API with .NET Framework, you still gonna have to add OData service, but then you don't have to do the dependency injection part, just add [EnableQuery] to your controller and you should be good to go!
Here's an example: th-cam.com/video/raRCU2sbDSg/w-d-xo.html
Really good stuff. Thank you.
Amazing!
Thank you a lot!
Great stuff! Thanks a lot!
It would be great than you could map queried data to a DTO, for me It's not quite a good idea to allow your whole entity structure be shown to clients
You can create automappers to map your model structure to a viewmodel structure where you show just enough.
Automapper and projection is working very well with OData and EFCore
When can we plug this into 3.1? Great work.
I didn't test it yet, but here is an article from Hassan about OData in asp.net core 3.1 devblogs.microsoft.com/odata/experimenting-with-odata-in-asp-net-core-3-1/
omg this is awsome maaaagic
Hi @
Hassan Habib! Great video and explanation! Thank you! I have a question: to practice, I'm play around Chinook databases (do you know?), and "expand" don't work for me, using it like you in your video. The result json show the value items like [ ]. The relation on databases through foreing key, indexes, etc are fine. Summarizing, it does not show the values tied by navigation properties. Please, can you give me any clue that may be failing? Thanks in advance!
Those 4 lines of code did work in .net core 3.1 . I have to do other config changes as well. Pls update this video with latest .net core version at least 3.1 onwards
Thanks guys amazing demo. But I have one question which I am having a hard time to figure out: is it possible to have both the existing WebAPI and the OData service leaving side by side but to access it with a different prefix like this ?
api/Students -> WebAPI
odata/Students -> OData
I am using .NET 6 / AspnetCore.OData 8
this is simply amazing
Great video!
WoW, it's super Amazing
Is there some possibility with the Expand feature to expand to only one level of relationship and not unlimited levels. This will prevent the user to query the whole database.
[EnableQuery(MaxExpansionDepth = 1)]
Wow, I got an Api to add a few lines of code and a client App to rebuild, thanks
Is there a git repo for this example?
Thank You...
It saves more time.. thanks!
thats really good. tnx
if a want to have this automatically for every table in my database how I could achieve this without using Entity Framework and map every table manually?
Isn´t OData also about the format, not only how to query the data? Does this also comes with the ASP.NET Core OData Package, how many lines of code would it took to add that? :)
Thank you Friends. it was awesome experience. I have worked with repository patten in that case what i can do.
Still works, as long as your repository object returns an IEnumerable or IQueryable.
how to get the XML response with OData? because I'm having a problem retrieving it, hope anyone could help.
Guys how can exposing the whole dbContext in controller to the world is the good idea?
That is exactly what im asking to myself, also i just asked if there is a way to pass the filter options to an underliying layer like a Service Layer to perform the filtering in that layer and not in the controller
What's the best approach to make it case insensitive?
Answer is?
good job, thanks
Esto me ayuda mejorar 🎉😊
When a another REST API is consumed by a Web API, is it a good idea to use OData?
When i use odata with async task await . . using the expand .. it is not working why ??
The funny thing is, the initial JSON response had lower case keys and the OData responses capital case keys. Pascal case is just weird.
Superb
Interesting stuff.
Nice demo, specially if you have an open API, but is there any way to map queries to DTOs and more importantly use AuthorizationHandler?
Très belle démonstration d'OData, Merci.
J'aurai bien aimé savoir comment et surtout à quelle moment les données sont traités (filtre, select,... )
Est ce que c'est vraiment au moment de l'exécution de la requête dans la base de données où une fois remontée, mais ça reste en mémoire côté serveur ?
Merci beaucoup
Awesome!!
Supper amazing!!
When I download the example and run it, it brings back the student and the school when I just request students.I thought you would only get students and if you did expand=School then you would get school info? The sample code doesn't behave like the video.
Does OData query on DB via Entity framework or does it only query on the results?
It depends on the return type, if your controller method is returning a IEnumerable it will perform differently than if it was returning IQueryable. if it's IQueryable OData will perform the search on the database via EF, if it's IEnumerable it will perform the query on the returned results. hope this helps.
@@HassanHabib This is great answer and really great feature. Thank you for the very informative video
@@HassanHabib This is awesome, because I guess most of ASP.NET Core APIs return IEnumerables from the injected services in the controllers. If you only need 4 lines of code to do all of this, it's f*cking magic! I would like to know how performance is affected with OData, but so far it's quite impressive. Thank you guys, loving all your stuff you are doing and I really hope .NET Core 3 will be a boom in the Software Development world.
For the secure reason, I don't want to share full entity from DataContext. Can I use OData for IQueryable instead of an entity?
Yes of course, you have full control over your return type on the controller method.
So... it is basically method interceptor / middleware.. right? Exposing IQueryable is good only for pretty small applications (RAD), because it is leaky abstraction - even with queryable mapping.
This is mapping Querystring -> LINQ expression.
Despite i am big critic of GraphQL/ ODATA because of their low usability in real big and performant applications i liek this idea, because it is easy to use and cool transfer-size optimizations.
@hassan how does the expand work without EF and .include() extension method? Just ignored? or you can modify mapping of that via configurations?
Out of context , how you do map open types in odata to entity framework core ?
Great. How to working odata with unit of work?
What do you mean? please elaborate.
Amazing, how now with .net 6 all of this needs to be re-recorded
Cool... Now how do I use consume an OData service in ASP.Net Core 3?
Not compatible with 3.0
well explained!
Does this work with .net Core 3.0?
Yes, here's how to do it: devblogs.microsoft.com/odata/experimenting-with-odata-in-asp-net-core-3-1/ and here as well: devblogs.microsoft.com/odata/enabling-endpoint-routing-in-odata/
This looks interesting. I was trying to add routeBuilder to -
app.UseWebApi() ( my app uses this). But I am not able to pass the routeBuilder predicate to this. Can someone help me out please?
Could elaborate more? what are you trying to do?
@@HassanHabib In Startup Configure(IAppBuilder) -> i am using app.UseWebApi(config) instead of UseMvc. And UseWebApi does not have routebuilder as argument. Can we somehow make this work with webapi as well?
@@sandyhills12 I see. if you're okay with going to 6 lines of code instead of 4 - you can do this: gist.github.com/hassanhabib/a63297a55e802157b353525c9d420363
Love it!
Do it bring all list into ram and process it in ram? Or query applied on Database? Its very important!
If you're running against an IQueryable, it will all run on the database.
@@HassanHabib that's great. thank you very much.
How did you came out of this error
"IServiceCollection' does not contain a definition for 'AddOData' and no accessible extension method 'AddOData' accepting a first argument of type 'IServiceCollection' could be found (are you missing a using directive or an assembly reference?)"
P.S: I am using the same directive as you used. i.e.
using Microsoft.AspNet.OData.Extensions;
please help me.
Did you install the right nuget package?
@@HassanHabib I figured it out. Thanks. I was using .net core for OData and we need other nuget package i.e. .netcore package to install and then do the samething.
Hi! Good video, thank you! What about restier for asp.net core?
Thank you for watching, we will try to address that.
Why is it bad to use a field like _context in this example? Was his only point to skip the underscore/rename it and use this.context instead?
Use a prefix for field names doesn't follow C# naming conventions/guidelines, this was a practice that was carried over from C++, here's the coding guideline reference: docs.microsoft.com/en-us/dotnet/standard/design-guidelines/names-of-type-members
This also is a good reference:
docs.microsoft.com/en-us/dotnet/standard/design-guidelines/general-naming-conventions
Hi. I hava a question. Is routeBuilder.EnableDependencyInjection(); required? As far as I know we can already use DI in controllers without writing this.
Yes, it's required for your non-Edm route
What about auto lookup the schools against the school name
You can using filtering to do that, so you can do $filter=Name eq 'School Name Here' something like that.
Where we can find source code which you have given in Demo?
Right here: github.com/hassanhabib/ODataDemo
Is it affecting the database query or just the return from the API?
If you're returning an IQueryable, it will run on the database.
amazing
Are those 13 or 15" Surface Book 2s?
15" :-)
oData is great. But sadly it breaks Swagger API Doc. Is there any Workaround for this behaviour?
Can certain capability be required per service? Like, api/Students needed to be filtered or paged?
As long as it's an API then it's OData-capable :-)
@@HassanHabib my question isn't clear. Let me try it again. If the filter has been enabled via Startup.cs, can it be required per endpoint. In the case of api/Students, filter must be supplied, else it'll throw an error. Is that possible?
I see what you're saying, yes you can make it per endpoint by passing a paramter through the [EnableQuery()] annotation that I used in the demo, for instance you can say: [EnableQuery(AllowedQueryOptions = Microsoft.AspNet.OData.Query.AllowedQueryOptions.Expand)] so this way you're only allowing expand but not anything else, there are more things you can do with the EnableQuery annotation to do a per-endpoint control work, does that answer your question?
@@HassanHabib Yes, you definitely did. Thank you. This will be really nice. This means that even though an IQueryable must be returned in order to run the query in the DB, it can prevent getting unfiltered data by requiring the endpoint to supply a filter. Cool stuff. 👍
Is it also available in asp.net web or mvc framework
Yes, here's an example: th-cam.com/video/ZCDWUBOJ5FU/w-d-xo.html
Isn't this the same with APIs that uses RQL?
Very, very similar, Open Data Protocol has a lot of different implementations RQL seems to be one of these implementations.
Show now an integration of OData with Swagger and you will have my slow clap
Same here, I added the OData to my controller, and works, but swagger don't. Im using net core 2.1
@@mspasiuk I'm working with the OData team to get this officially released - should be out officially shortly.
@Hassan Habib Thanks!
🤣🥳🥳🥳
i did it at work this month ;)
Well, if you want the client-side capability more than service end-point can provide, then, in essence, you need to write SQL type query. To do that, you need to know the data schema of the source system.
If you are going to that direction, then I would question the whole idea of the service concept and service encapsulation.
Is it similar to GraphQL?
GraphQL is similar to OData, since OData came out first in 2007.
Interesting if I can do that with Dapper on SQL server... And also it would be great to have explanations for net core 3.0
We will make more videos around the subject and touch on net core 3.0
@@HassanHabib One year on, do you have video on this subject? Can you share here if you do, I can't find anything on this.
If i query schools and want to $epand all the students as a list it is not working. Can any one tell me what goes wrong?
impressive