Introdução ao desenvolvimento de backend em Kotlin usando Spring Boot 3 e MongoDB

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@GetMapping("/hello")
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fun hello(@RequestParam(value = "name", defaultValue = "World") name: String?): String {
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    return String.format("Hello %s!", name)
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}

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@SpringBootApplication
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@RestController
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class HelloBackendWorldApplication {
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    @GetMapping("/hello")
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    fun hello(): String {
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        return "Hello World!"
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    }
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}
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fun main(args: Array<String>) {
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    runApplication<HelloBackendWorldApplication>(*args)
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}

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spring.data.mongodb.uri = mongodb + srv ://<username>:<pwd>@<cluster>.mongodb.net/<dbname>

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@Document("restaurants")
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data class Restaurant(
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    @Id
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    val id: ObjectId = ObjectId(),
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    val address: Address = Address(),
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    val borough: String = "",
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    val cuisine: String = "",
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    val grades: List<Grade> = emptyList(),
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    val name: String = "",
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    @Field("restaurant_id")
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    val restaurantId: String = ""
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)
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data class Address(
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    val building: String = "",
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    val street: String = "",
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    val zipcode: String = "",
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    @Field("coord")
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    val coordinate: List<Double> = emptyList()
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)
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data class Grade(
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    val date: Date = Date(),
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    @Field("grade")
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    val rating: String = "",
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    val score: Int = 0
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)

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interface Repo : MongoRepository<Restaurant, String> {
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    fun findByRestaurantId(id: String): Restaurant?
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}

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@RestController
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@RequestMapping("/restaurants")
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class Controller(@Autowired val repo: Repo) {
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}

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@RestController
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@RequestMapping("/restaurants")
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class Controller(@Autowired val repo: Repo) {
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    @GetMapping
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    fun getCount(): Int {
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        return repo.findAll().count()
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    }
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}

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interface Repo : MongoRepository<Restaurant, String> {
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    fun findByRestaurantId(restaurantId: String): Restaurant?
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}

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@GetMapping("/{id}")
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fun getRestaurantById(@PathVariable("id") id: String): Restaurant? {
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    return repo.findByRestaurantId(id)
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}

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    @GetMapping("/{id}")
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fun getRestaurantById(@PathVariable("id") id: String): ResponseEntity<Restaurant> {
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    val restaurant = repo.findByRestaurantId(id)
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    return if (restaurant != null) ResponseEntity.ok(restaurant) else ResponseEntity
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        .notFound().build()
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}

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    @PostMapping
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fun postRestaurant(): Restaurant {
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    val restaurant = Restaurant().copy(name = "sample", restaurantId = "33332")
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    return repo.insert(restaurant)
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}

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    @PatchMapping("/{id}")
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fun updateRestaurant(@PathVariable("id") id: String): Restaurant? {
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    return repo.findByRestaurantId(restaurantId = id)?.let {
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        repo.save(it.copy(name = "Update"))
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    }
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}

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    @DeleteMapping("/{id}")
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fun deleteRestaurant(@PathVariable("id") id: String) {
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    repo.findByRestaurantId(id)?.let {
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        repo.delete(it)
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    }
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}