Reactive template API

- [Instructor] In this next video, we will be checking out the Reactive Data Layer. First of all, let's take a look a reactive templates. Reactive templates live in the Spring Reactive Data part of the stack. Okay, so what exactly is a reactive template? It is a interface that specifies a basic set of operations executed in a reactive way. Reactive templates form the foundation for Spring Data reactive repositories.

For most operations in the blocking template API, there is a corresponding operation in the reactive template. ReactiveMongoOperations is a reactive template. It is a interface that specifies a basic set of MongoDB operations. These operations are executed in a reactive way. ReactiveMongoOperations is a fluent style API that extends the interface ReactiveFluentMongoOperations.

An example of a implementation of ReactiveMongoOperations is the ReactiveMongoTemplate. This template basically simplifies the use of Reactive MongoDB. Additionally, it contains guardrails that help us avoid common errors. This template focuses on executing the core MongoDB workflow, while application code is expected to provide the Document Model and extract results in a format that it needs.

The ReactiveMongoTemplate executes binary JSON queries, or updates, and we can use a SimpleReactiveMongoDatabaseFactory to get a template instance for a bean that we would be able to autowire into our service layer. Now let's take a look at a code example from ReactiveMongoTemplate. In this example, we map the results of an ad hoc query on a collection to a instance of an object of Type T.