Lesson 40

lesson15-host/docker-compose.yml

@@ -15,18 +15,6 @@ services:
     ports:
       - 5432:5432
 
-  db-tests:
-    container_name: db-tests
-    build:
-      context: ../lesson13-agendify-repository-jdbi
-      dockerfile: ../lesson13-agendify-repository-jdbi/tests/Dockerfile-db-test
-    environment:
-      - POSTGRES_USER=dbuser
-      - POSTGRES_PASSWORD=changeit
-      - POSTGRES_DB=db
-    ports:
-      - 5432:5432
-
   # agendify-jvm-1 and agendify-jvm-2 are used to illustrate scenarios with a fixed number of servers
   # with static and well know names.
   agendify-jvm-1:
@@ -35,7 +23,7 @@ services:
     image: agendify-jvm
     environment:
       PORT: 8081
-      DB_URL: "jdbc:postgresql://db-tests:5432/db?user=dbuser&password=changeit"
+      DB_URL: "jdbc:postgresql://agendify-postgres-test:5432/db?user=dbuser&password=changeit"
     ports:
       - 8081:8081
   agendify-jvm-2:
@@ -44,7 +32,7 @@ services:
     image: agendify-jvm
     environment:
       PORT: 8082
-      DB_URL: "jdbc:postgresql://db-tests:5432/db?user=dbuser&password=changeit"
+      DB_URL: "jdbc:postgresql://agendify-postgres-test:5432/db?user=dbuser&password=changeit"
     ports:
       - 8082:8082
 

lesson15-host/test-infra/Dockerfile-postgres-test

@@ -0,0 +1,12 @@
+FROM postgres
+
+USER postgres
+WORKDIR /app
+
+COPY src/sql/create-schema.sql /docker-entrypoint-initdb.d/1_create.sql
+COPY src/sql/insert-test-data.sql /docker-entrypoint-initdb.d/2_insert-test-data.sql
+
+COPY --chown=postgres:postgres ./tests/scripts/wait-for-postgres.sh ./bin/wait-for-postgres.sh
+RUN chmod +x ./bin/wait-for-postgres.sh
+
+EXPOSE 5432

lesson40-demo-load-balancing/build.gradle.kts

@@ -0,0 +1,28 @@
+plugins {
+    kotlin("jvm") version "1.9.25"
+}
+
+group = "pt.isel"
+version = "unspecified"
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation("org.springframework:spring-core:6.0.0")
+
+    // To use SLF4J
+    // For logging purposes
+    implementation("org.slf4j:slf4j-api:2.0.16")
+    runtimeOnly("org.slf4j:slf4j-simple:2.0.16")
+
+    testImplementation(kotlin("test"))
+}
+
+tasks.test {
+    useJUnitPlatform()
+}
+kotlin {
+    jvmToolchain(21)
+}

lesson40-demo-load-balancing/src/main/kotlin/pt/isel/App.kt

@@ -0,0 +1,23 @@
+package pt.isel
+
+import org.slf4j.LoggerFactory
+import org.springframework.util.StopWatch
+import java.net.URI
+import java.net.http.HttpClient
+import java.net.http.HttpRequest
+import java.net.http.HttpResponse.BodyHandlers
+
+private val logger = LoggerFactory.getLogger("main")
+
+fun main() {
+    val httpClient = HttpClient.newHttpClient()
+    val request = HttpRequest.newBuilder(URI.create("http://localhost:8088/api/status/ip")).GET().build()
+    while (true) {
+        val sw = StopWatch().also { it.start() }
+        logger.info("Request sent...")
+        val response = httpClient.send(request, BodyHandlers.ofString())
+        sw.stop()
+        logger.info("...response received: {}, {}, {}", response.statusCode(), sw.totalTimeMillis, response.body())
+        Thread.sleep(2000)
+    }
+}

settings.gradle.kts

@@ -22,3 +22,4 @@ include("lesson13-agendify-repository-jdbi")
 include("lesson15-host")
 include("lesson16-http-pipeline")
 include("lesson18-agendify-SSE")
+include("lesson40-demo-load-balancing")