make auth work

src/main/kotlin/com/restapi/Main.kt

@@ -1,7 +1,12 @@
 package com.restapi
 
+import AuthTokenResponse
 import com.fasterxml.jackson.databind.JsonMappingException
+import com.fasterxml.jackson.module.kotlin.readValue
 import com.restapi.config.AppConfig.Companion.appConfig
+import com.restapi.config.Auth
+import com.restapi.config.Auth.getAuthEndpoint
+import com.restapi.config.AuthEndpoint
 import com.restapi.domain.DataModel
 import com.restapi.domain.DataNotFoundException
 import com.restapi.domain.Session
@@ -9,6 +14,9 @@ import com.restapi.domain.Session.creatSeq
 import com.restapi.domain.Session.database
 import com.restapi.domain.Session.findByEntityAndId
 import com.restapi.domain.Session.nextUniqId
+import com.restapi.domain.Session.objectMapper
+import com.restapi.domain.Session.redis
+import com.restapi.domain.Session.setAuthorizedUser
 import io.ebean.CallableSql
 import io.ebean.DuplicateKeyException
 import io.ebean.RawSqlBuilder
@@ -17,10 +25,18 @@ import io.javalin.apibuilder.ApiBuilder.*
 import io.javalin.http.*
 import io.javalin.json.JavalinJackson
 import org.slf4j.LoggerFactory
+import java.net.URI
+import java.net.URLEncoder
+import java.net.http.HttpClient
+import java.net.http.HttpRequest
+import java.net.http.HttpRequest.BodyPublishers
+import java.net.http.HttpResponse.BodyHandlers
+import java.nio.charset.StandardCharsets
 import java.time.LocalDateTime
 
 fun main(args: Array<String>) {
     val logger = LoggerFactory.getLogger("api")
+
     Javalin
         .create { cfg ->
             cfg.http.generateEtags = true
@@ -39,7 +55,47 @@ fun main(args: Array<String>) {
             cfg.jsonMapper(JavalinJackson(Session.objectMapper))
         }
         .routes {
-            before("/*") { ctx ->
+
+            path("/auth") {
+                get("/init") {
+                    val endpoint = getAuthEndpoint().authorizationEndpoint
+
+                    val redirectUrl =
+                        "$endpoint?response_type=code&client_id=${appConfig.iamClient()}&redirect_uri=${appConfig.iamClientRedirectUri()}&scope=profile&state=1234zyx"
+                    it.redirect(redirectUrl)
+                }
+                get("/code") {
+
+                    val code = it.queryParam("code") ?: throw BadRequestResponse("not proper")
+
+                    val ep = getAuthEndpoint().tokenEndpoint
+                    val client = HttpClient.newHttpClient()
+                    val req = HttpRequest.newBuilder()
+                        .uri(URI.create(ep))
+                        .POST(
+                            BodyPublishers.ofString(
+                                getFormDataAsString(
+                                    mapOf(
+                                        "code" to code,
+                                        "redirect_uri" to appConfig.iamClientRedirectUri(),
+                                        "client_id" to appConfig.iamClient(),
+                                        "grant_type" to "authorization_code",
+                                    )
+                                )
+                            )
+                        )
+                        .header("Content-Type", "application/x-www-form-urlencoded")
+                        .build()
+                    val message = client.send(req, BodyHandlers.ofString()).body()
+                    val atResponse = objectMapper.readValue<AuthTokenResponse>(message)
+
+                    //lets keep auth token refreshed
+                    redis.sadd("AUTH_TOKEN", message)
+                    it.result(atResponse.accessToken).contentType(ContentType.TEXT_PLAIN)
+
+                }
+            }
+            before("/api/*") { ctx ->
                 //validate, auth token
 
                 //allow only alpha, numeric, hypen, underscore, dot in paths
@@ -51,6 +107,12 @@ fun main(args: Array<String>) {
                             throw IllegalArgumentException()
                         }
                     }
+
+                val at = ctx.header("Authorization")?.replace("Bearer ", "")?.replace("Bearer: ", "")?.trim()
+                    ?: throw UnauthorizedResponse()
+                val pt = Auth.parseAuthToken(authToken = at)
+
+                setAuthorizedUser(pt)
             }
             path("/api") {
                 post("/execute/{name}") {
@@ -174,4 +236,17 @@ data class Query(
     val params: Map<String, Any>
 )
 
+private fun getFormDataAsString(formData: Map<String, String>): String {
+    val formBodyBuilder = StringBuilder()
+    for ((key, value) in formData) {
+        if (formBodyBuilder.length > 0) {
+            formBodyBuilder.append("&")
+        }
+        formBodyBuilder.append(URLEncoder.encode(key, StandardCharsets.UTF_8))
+        formBodyBuilder.append("=")
+        formBodyBuilder.append(URLEncoder.encode(value, StandardCharsets.UTF_8))
+    }
+    return formBodyBuilder.toString()
+}
+
 data class PatchValue(val key: String, val value: Any)