Some of the major topics that we will cover include learning about different ways to test your application, using the inmemory and sqlite database providers with entity framework core, test isolation, and logging entity framework core logs to test explorer. It provides the similar database functionality without over heading the actual database. As we know dbcontext is an autogenerated code created and customized using scaffolding commands in entity framework tools. You will see how to bring entity framework into a project based on an existing database. Entity framework core in memory testing database gary. Integration testing with nunit and entity framework in the previous post, using nunit and entity framework dbcontext to programmatically create sql server ce databases and specify the database directory, a basic way was shown to how to create a new db using entity framework s dbcontext programmatically. What this means, is that with a single option setting, your tests can interact directly with the database or at least efs impression of the database but not actually touch any physical database. Unit testing with entity framework and entity framework core.
Unit testing odata web apientity framework applications. The purpose is to validate that each unit of the software performs as designed. Using entity framework core inmemory database for unit testing. All code in the examples make use of my current favourite unit testing framework xunit, but should be fairly easy to convert to any of the others. In memory test doubles can be a good way to provide unit test level. Database integration testing with entity framework code. Architects and developers of dataoriented applications have typically struggled with the need to achieve two very different objectives. Entity framework dbcontext looks simple to mock by great tools like moq. Some changes are made to be compliant with stylecopcodeanalysis. Dec, 20 it shows how to modify the scaffolded controller to enable passing a context object for testing, and how to create test objects that work with entity framework. Mocking and unit testing dbcontext entity framework core today in this article, we will see how to get started with the unit testing entity framework dbcontext class. Entity framework and domain driven design testability. Jun 21, 2017 practical application architecture with entity framework core. Now you can just start writing your unit tests without thinking about mocking dbcontext.
Sep 16, 2018 this entry was posted in entity framework, entity framework core, unit testing and tagged entity framework, entity framework core, moq, nsubstitute, unit test, useinmemorydatabase on september 16, 2018 by pcmichaels. Consider testing a piece of business logic that might need to use some data from a database, but is not inherently testing the database interactions. I stumbled upon several sites, articles, examples and even courses. Why entity framework core is an implementation of the unit of work and repository pattern. Net mvc and unit testing triangle we will see how we can implement generic repository pattern with entity framework and how to. It follows ansi standards while supporting most embedded compiler quirks. However, hard to read and brittle unit tests can wreak havoc on your code base. This blog posts shows how to unit test controllers that use data from entity framework core. Net, unit testing, and mistakes to avoid when architecting software with. Apr 18, 2019 while writing the book entity framework core in action i wrote over 600 unit tests, which taught me a lot about unit testing ef core applications. Creating a simple library that uses entity framework. The entity framework dbcontext is a unit of work and important to understand. My concern is that using entity framework means directly working with data source. These are the sorts of tests you should create during test driven development.
I have dabbled before but now i am determined to add it to my workflow and write better software. Save time mocking use your real entity framework dbcontext in. As you can see in this post ef core has an inmemory context that is useful for unit testing. Unit testing can be beneficial to many aspects in software develepment, from the lowest level that is the source code to. From adding references to understanding how all the pieces fit together. Jan 15, 2019 recently i got asked to explain how to unit test a controller that retrieves data using an entity framework core dbcontext. Mar 14, 2020 mocking and unit testing dbcontext entity framework core today in this article, we will see how to get started with the unit testing entity framework dbcontext class. In this post im going to show you how to use genfu, moq and xunit to create small and isolated unit tests for your asp. Once you need some data in the database simply use entity framework to manipulate your data. It is also about being able to performance optimize your persistence when needed by making drastic structural changes. Richard hi, im richard goforth, and welcome to this course, where we will cover software architecture with entity framework core.
This will improve the reliability of your tests and code. Im a microsoft mvp and freelance solution architect currently focused on security and building apis. The inmemory data provider in entity framework makes life simpler by letting you test the code of your asp. When unit testing this i cant fake it since the repository returns a concrete implementation and not a interface, which i think is the right way, since when dealing with a orm like ef, with the possibility to track entities and other mechanisms we shouldnt loose that by. In entity framework core, we have two packages which help us to create the database on runtime as similar to the actual database and its tables as well. Testing with a mocking framework ef6 microsoft docs.
Aug 30, 2017 addrangeasync is a method of entity framework core and the purpose of this project is mocking an entity framework 6 context. Aug 19, 2017 finding concrete documentation to implement unit testing with entity framework was a little challenging, in my opinion. That is, entity framework core can use an inmemory database, which is useful for things like unit testing. Unit testing is a level of software testing where individual units components of a software are tested. Entity framework core makes it easy to write tests that execute against an inmemory store. Net that support the development of dataoriented software applications. Unit testing with entity framework and entity framework core 2.
It is paramount if you want to be able to release regularly and quickly. Jan 08, 2018 why entity framework core is an implementation of the unit of work and repository pattern. Juval lowy, in his talk the zen of software architecture in devintersection 2017 orlando, fl said that, and im paraphrasing, unit tests are. Its a fundamental construct in the designof entity framework, so its importantto understand what it is and what it providesto the application architecture. Testing with the inmemory provider in entity framework. Testing code that uses ef core ef core microsoft docs. They must model the entities, relationships, and logic of the business problems. Entity framework core is a crossplatform way to access data from an application, but poor architectural choices can make it more trouble than other data access technologies. This readme defines the various groups, with links to the documentation in the efcore. It also ensures our unit tests run quickly so we arent left waiting hours for a large test suite to complete. The problem with entity framework is that it depends on the existance of a real database to run correctly. I have an existing database for which i generated entities and a datacontext, and have partial classes for holding my methods and any additional nondatabase properties. But the in memory database doesnt support execution of stored procedures in any way. Unit tests are part of a quick feedback cycle to facilitate change and preserve the maintainability of software as complexity increases.
It is defined by martin fowler in his book,the principles of enterprise architecture, this way. This article describes some best practices regarding unit test design for your. Net developers to work with relational data using domainspecific objects. Net mvc, unit testing with entity framework, and finally some patterns to avoid when architecting software. By the end of this course, youll know all about testing with entity framework core. Now, granted that there are a number of other possible ways to fake out a database and conduct unit test, but i havent found one that i thought was as simple to implement as with entity framework core. Mocking entity framework dbcontext with moq software architect. Integration testing with nunit and entity framework. Do not worry about ids, keys, or virtual properties everything will work in exactly the same way as with entity framework and an ordinary database. Effort entity framework fake objectcontext realization tool, via nuget. Setupdata extension method is part of entityframework. While the situation will improve with the introduction of entity framework 7 and its inmemory data store, for now we still have to find a way of mocking dbcontext if we want to test code that uses it directly.
However, we never try to mock dbcontext or iqueryable. Unity is equally happy running tests for an 8bit microcontroller as it is a 64bit processor on steroids. Jan 14, 2018 the other day i went browsing on the web to see how other people approach database integration testing with entity framework. Inmemory dbcontext with entity framework core mirko maggioni unit testing july 1, 2017 july 1, 2017 frequently, when we need to test a ef context from our unit test class, we need to implement a stub of the context manually, in order to have, for example, an in. It usually has one or a few inputs and usually a single output. Net boilerplate framework using xunit, entity framework, effort and shouldly. Net core has brought with it most of the firstclass unit testing tools. Unit testing business logic that is based on entity framework is a difficult task. It features a rich set of assertions so you can find the. If you want to learn how to easily write unit tests for entity framework, read on.
To use the inmemory database provider first we need to add the following nuget package. It is about being able to unit test the code that is interesting to unit test. Welcome to my course, testing with entity framework core. If i am not concerned with unit testing and switching my data access out at a later time, would using my entity framework objects as my business objects be okay. For easier unit testing, entity framework core offers a memorybased povider. Full source code available here entity framework core has made unit testing crud functions much easier, see here for an example of using the in memory database, it allows you to search, add, remove and update rows but the in memory database doesnt support execution of stored procedures in any way. Finding concrete documentation to implement unit testing with entity framework was a little challenging, in my opinion. I want to test my entities that are built using entity framework. Sep 19, 2012 unit testing business logic that is based on entity framework is a difficult task. Apr 19, 2017 using entity framework core inmemory database for unit testing april 19, 2017 october 7, 2019 gunnar peipman 4598 views 21 comments asp. Dbcontext mocking and unit testing entity framework core. Database integration testing with entity framework code first.
That post was built on a prerelease version of entity framework so i thought id provide an updated post on top of the dbcontext api surface we ended up shipping. One option is to use a test double such as a mock or fake. Using an inmemory store is convenient since we dont need to worry about setting up a relational database. In this course, integration testing of entity framework applications, youll learn that a good integration test suite is the best way to ensure the quality of your entity framework application. How many times have you spotted software architecture that utilizes. Inmemory dbcontext with entity framework core mirko. This tutorial assumes you are familiar with the basic concepts of asp. The aim of unit testing is to test the business logic in isolation without dependencies on other components of the system. Inmemory test doubles can be a good way to provide unit test level. The goal is to mock ef so that you can test this method without requiring a database on your build server. Testing entity framework core using inmemory database provider. Instructor now that we have the repository pattern,we can discuss the unit of work. The goal is to write unit tests which stub out the actual db calls. In this course, we are going to learn how to test code that depends on calls into your database through entity framework core.
Net core and entity framework core then unit testing is very easy. If we choice the first option, with a database like sql localdb, well have performance problems because the cost of the database creation and the data. A unit is the smallest testable part of any software. You can write a unit test against a mock context as follows. Moq provides a helpful extension method to mock entityframeworks dbsets using moq. Finally you will explore testing and set up a further learning path by writing unit and integration tests. When we have to test methods that involves entity framework, a typical choice that we have to face is use integration tests, with an effective database, or unit tests. The previous implementations of entity framework, prior to version 6 and core, were not exactly a full implementation of the repository and unit of work pattern. Database integration testing with entity framework code first in. Net app against an inmemory database instead of having to install and configure the real. In this lightning talk, well look at how using the ef core inmemory provider will simplify your unit testing approach. What happens is that you need to test some method that does some stuff and also happens to make an ef call to the database. What the lack of devops can cause in a software development. Unit testing on top of entity framework dbcontext on code design, data access, entity framework, quality, repository when writing unit tests one of the challenges is to isolate your tests.
The entity framework is a set of technologies in ado. This guidance and application demonstrate how to create unit tests for your web api 2 application that uses the entity framework. You can use the same context you use with sql server or other providers with the memorybased provider. Nov 21, 2017 entity framework core has made unit testing crud functions much easier, see here for an example of using the in memory database, it allows you to search, add, remove and update rows. So, when i wrote the chapter on unit testing, which was the last in the book, i combined what i had learn into a library called efcore. Entity framework core in memory testing database gary woodfine. Practical application architecture with entity framework core. We use test doubles for internal testing of ef core.
This article explains how you can configure entity framework core to use the memorybased provider for unit testing. May 12, 2015 unit testing on top of entity framework dbcontext on code design, data access, entity framework, quality, repository when writing unit tests one of the challenges is to isolate your tests from everything. How to mock entity frameworks dbcontext for unit testing. First, youll set up a continuous integration server to rebuild a database and run all integration tests on every checkin. Unit testing with inmemory provider and sqlite inmemory. In this case using a sqlite inmemory, which is very fast to setup and run see my article using inmemory databases for unit testing ef core applications for when and how you can use this type of database for unit testing. I am just starting out with unit testings and tdd in general. No one is on the fence about whether you should be unit testing entity framework by itself. Now i show you a typical unit test where i seed the database from the data stored in the json file.
This means that entity framework can use an optimistic concurrency model to determine if that database has changed since you initially pulled your entities. Entity framework ef is the tool of choice for dataoriented development in. In this blog post, senior premier developer consultant monu bambroo demonstrates how to easily unit test an odata based web api service which is consuming data from sql db using entity framework. Integration testing with entity framework core and sql. Testsupport is an opensource library mit licence with a nuget package available. The problem with unit testing code that uses entity framework classes, such as dbcontext, is that the classes are difficult to mock. Apr 11, 2009 now recall that entity frameworks implementation of unit of work involves tracking the initial state of each entity. How are people unit testing with entity framework 6, should you. Simplified unit testing with the entity framework core. Microsoft mvp and ef expert phil japikse walks through the highlights of entity framework 6. The other day i went browsing on the web to see how other people approach database integration testing with entity framework. Unit testing entity framework core stored procedures no. Entity framework core has made it really easy to set up and configure inmemory database options, reducing the amount of ceremony and configuration one has to do to get it up and running. Net core applications can be tested with different testing frameworks and entity framework core makes testing specially easy by removing different technical problems from our way by using inmemory data provider.
Using entity framework core inmemory database for unit. Two strategies for testing entity framework effort and. It shows how to modify the scaffolded controller to enable passing a context object for testing, and how to create test objects that work with entity framework. What is entity framework entity framework ef is an objectrelational mapper that enables. Testing provides an implementation of dbasyncqueryprovider that can be used when testing a component that uses async queries with entityframework the project is cut from entityframeworks source code. Entity framework allows you to achieve this by creating a context with. Clean unit testing is an essential part of achieving a maintainable code base. While writing the book entity framework core in action i wrote over 600 unit tests, which taught me a lot about unit testing ef core applications. In this post im going to show you how to use the inmemory database with named instances.
Two strategies for testing entity framework effort and sql. Unity is designed to help you make the most of your test suite. In conclusion, you will learn about additional areas entity framework core can be used in, and what types of data structure besides rdbms can be. The basic purpose of unit testing is to test the methods of business logic of asp. Unit testing tools are divided into a number of categories. The problem with entity framework is that it depends. Unit testing entity framework used to be quite a chore, but over the past few years it has become significantly easier. Thats not to say you cant write working software this way, but its not following solid and its not using repository and uow patterns since the.
910 610 1320 1168 729 703 1255 704 1413 754 136 757 810 1373 730 566 303 1463 688 1430 955 662 1335 121 640 274 326 852 774 250 293 681 659 729 1213 86