finished tutorial

Author: rojiani

README.md

@@ -1,4 +1,17 @@
 Simple REST API Kotlin + Spring Boot
 ====================================
 
-Code from following tutorial - https://scotch.io/@grahamcox82/how-to-build-a-simple-rest-api-with-kotlin-and-spring-boot
+Code from this [scotch.io tutorial](https://scotch.io/@grahamcox82/how-to-build-a-simple-rest-api-with-kotlin-and-spring-boot).
+
+[Tutorial Code](https://github.com/sazzer/kotlin-with-spring-boot)
+
+---
+
+This repository is an example on how to write a Web API using the Kotlin programming language and the Spring Boot framework.
+
+Build and run the example by simply executing `gradle bootRun`, and then call the various endpoints to see the examples in action:
+
+* http://localhost:8080/answer
+* http://localhost:8080/user
+* http://localhost:8080/string/abc[?operation=[reverse,upper,lower]]
+* http://localhost:8080/raiseError

src/main/kotlin/tutorial/Application.kt

@@ -2,6 +2,7 @@ package tutorial
 
 import org.springframework.boot.SpringApplication
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration
+import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Configuration
 
 
@@ -12,7 +13,11 @@ import org.springframework.context.annotation.Configuration
  */
 @EnableAutoConfiguration
 @Configuration
-class Application
+class Application {
+
+    @Bean
+    fun controller() = FirstController()
+}
 
 /**
  * Run the application

src/main/kotlin/tutorial/FirstController.kt

@@ -0,0 +1,74 @@
+package tutorial
+
+import org.springframework.http.HttpStatus
+import org.springframework.web.bind.annotation.ExceptionHandler
+import org.springframework.web.bind.annotation.PathVariable
+import org.springframework.web.bind.annotation.RequestBody
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.RequestMethod
+import org.springframework.web.bind.annotation.RequestParam
+import org.springframework.web.bind.annotation.ResponseStatus
+import org.springframework.web.bind.annotation.RestController
+import java.time.Instant
+
+@RestController
+class FirstController {
+
+    /**
+     * The ultimate answer to life, the universe and everything
+     */
+    @RequestMapping("/answer")
+    fun answer() = 42
+
+    /**
+     * Get the details of a user
+     */
+    @RequestMapping("/user")
+    fun user(): User = User(
+        username = "nrojiani",
+        screenName = "Navid",
+        email = "[email protected]",
+        registered = Instant.now()
+    )
+
+    /**
+     * Perform some string manipulation on the given value
+     * @param value The value to manipulate (path variable)
+     * @param operation The operation to perform (query param)
+     */
+    @RequestMapping("/string/{value}")
+    @ResponseStatus(HttpStatus.CREATED)
+    fun manipulateString(
+        @PathVariable value: String,
+        @RequestParam(name = "operation", defaultValue = "none") operation: String
+    ): String = when (operation.toUpperCase()) {
+        "REVERSE" -> value.reversed()
+        "UPPER" -> value.toUpperCase()
+        "LOWER" -> value.toLowerCase()
+        else -> value
+    }
+
+    /**
+     * Pretend to create a new user
+     * @param user The details of the user to create
+     */
+    @RequestMapping(value = "/user", method = arrayOf(RequestMethod.POST))
+    fun createUser(@RequestBody user: NewUser): User {
+        return User(
+            username = user.username,
+            screenName = user.screenName,
+            email = user.email,
+            registered = Instant.now()
+        )
+    }
+
+    /** Cause an error to occur */
+    @RequestMapping("/raiseError")
+    fun raiseError(): Unit = throw IllegalArgumentException("This shouldn't have happened")
+
+    /** Handle the error */
+    @ExceptionHandler(IllegalArgumentException::class)
+    @ResponseStatus(code = HttpStatus.CONFLICT)
+    fun handleError(e: IllegalArgumentException): String? = e.message
+
+}

src/main/kotlin/tutorial/NewUser.kt

@@ -0,0 +1,16 @@
+package tutorial
+
+import com.fasterxml.jackson.annotation.JsonCreator
+
+/**
+ * Representation of a User to create
+ * @property username The username of the user
+ * @property screenName The screen name of the user
+ * @property email The email address of the user
+ */
+data class NewUser
+    @JsonCreator constructor(
+        val username: String,
+        val screenName: String,
+        val email: String
+    )

src/main/kotlin/tutorial/User.kt

@@ -0,0 +1,17 @@
+package tutorial
+
+import java.time.Instant
+
+/**
+ * Representation of a User
+ * @property username The username of the user
+ * @property screenName The screen name of the user
+ * @property email The email address of the user
+ * @property registered When the user registered with us
+ */
+data class User(
+    val username: String,
+    val screenName: String,
+    val email: String,
+    val registered: Instant
+)

src/main/resources/application.yml

@@ -0,0 +1,6 @@
+spring:
+    jackson:
+        serialization:
+            indent_output: true
+            write_dates_as_timestamps: false
+            write_durations_as_timestamps: false