Merge pull request #47 from code-freak/feature/reverse-proxy

Add reverse proxy support via Traefik

Vagrantfile

@@ -12,6 +12,7 @@ Vagrant.configure("2") do |config|
   config.vm.network "private_network", ip: "10.12.12.100"
 
   config.vm.network "forwarded_port", guest: 2375, host: 2375
+  config.vm.network "forwarded_port", guest: 80, host: 8081
 
   # Enable the automatic install of docker and make it available via TCP
   # We bind to 0.0.0.0 because the VM and Host are on a private network
@@ -22,6 +23,14 @@ Vagrant.configure("2") do |config|
   # $ docker ps -a
   #
   config.vm.provision "docker" do |d|
+    # Run Traefik as reverse proxy inside the VM
+    # It is available on port 8081 on the host
+    d.run "traefik",
+      cmd: "--loglevel=info --docker=true --docker.exposedbydefault=false",
+      args: "-p 80:80 -v /var/run/docker.sock:/var/run/docker.sock"
+    d.run "portainer/portainer", # credentials admin:admin
+      cmd: "-H unix:///var/run/docker.sock --admin-password='$2y$05$n8b3wSfBtMdMY1ei4FBx..qbvqlHx7Rpln7Wd61HQYcIJ7pWgGH7q'",
+      args: '-v /var/run/docker.sock:/var/run/docker.sock -l="traefik.enable=true" -l="traefik.frontend.rule=PathPrefixStrip: /portainer/" -l="traefik.port=9000" --name portainer'
     # Make daemon accessible via tcp and restart to apply changes
     d.post_install_provision "shell", inline: <<-eol
       sed -i '/ExecStart=/c\ExecStart=/usr/bin/dockerd -H fd:// -H tcp://0.0.0.0:2375 --containerd=/run/containerd/containerd.sock' /lib/systemd/system/docker.service \

build.gradle

@@ -101,3 +101,7 @@ test {
     exceptionFormat "full"
   }
 }
+
+task vagrantTest(type: Test) {
+  systemProperty "code-freak.docker.host", "http://localhost:2375"
+}

src/main/kotlin/de/code_freak/codefreak/frontend/AssignmentController.kt

@@ -45,8 +45,9 @@ class AssignmentController : BaseController() {
     val submission = getSubmission(request, assignmentId)
 
     // start a container based on the submission for the current task
-    val containerId = containerService.startIdeContainer(submission.getAnswerForTask(taskId)!!)
-    val containerUrl = containerService.getIdeUrl(containerId)
+    val answer = submission.getAnswerForTask(taskId)!!
+    containerService.startIdeContainer(answer)
+    val containerUrl = containerService.getIdeUrl(answer.id)
 
     model.addAttribute("ide_url", containerUrl)
     return "ide-redirect"

src/main/kotlin/de/code_freak/codefreak/service/ContainerService.kt

@@ -3,17 +3,17 @@ package de.code_freak.codefreak.service
 import com.spotify.docker.client.DockerClient
 import com.spotify.docker.client.messages.ContainerConfig
 import com.spotify.docker.client.messages.HostConfig
-import com.spotify.docker.client.messages.PortBinding
 import de.code_freak.codefreak.entity.Answer
 import org.apache.commons.io.IOUtils
 import org.slf4j.LoggerFactory
 import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.beans.factory.annotation.Value
 import org.springframework.boot.context.event.ApplicationReadyEvent
 import org.springframework.context.event.EventListener
 import org.springframework.stereotype.Service
 import java.lang.IllegalArgumentException
+import java.util.UUID
 import javax.transaction.Transactional
-import kotlin.random.Random
 
 @Service
 class ContainerService(
@@ -25,13 +25,15 @@ class ContainerService(
     val DOCKER_IMAGES = listOf(
         IDE_DOCKER_IMAGE
     )
-    const val LABEL_PREFIX = "de.code-freak."
-    const val LABEL_TASK_SUBMISSION_ID = LABEL_PREFIX + "task-submission-id"
-    const val LABEL_THEIA_PORT = LABEL_PREFIX + "theia-port"
+    private const val LABEL_PREFIX = "de.code-freak."
+    const val LABEL_ANSWER_ID = LABEL_PREFIX + "answer-id"
   }
 
   private val log = LoggerFactory.getLogger(this::class.java)
 
+  @Value("\${code-freak.traefik.url}")
+  private lateinit var traefikUrl: String
+
   /**
    * Pull all required docker images on startup
    */
@@ -48,7 +50,7 @@ class ContainerService(
    * Start an IDE container for the given submission and returns the container ID
    * If there is already a container for the submission it will be used instead
    */
-  fun startIdeContainer(answer: Answer): String {
+  fun startIdeContainer(answer: Answer) {
     // either take existing container or create a new one
     val containerId = this.getIdeContainer(answer) ?: this.createIdeContainer(answer)
     // make sure the container is running. Also existing ones could have been stopped
@@ -57,8 +59,6 @@ class ContainerService(
     }
     // prepare the environment after the container has started
     this.prepareIdeContainer(containerId, answer)
-
-    return containerId
   }
 
   /**
@@ -80,19 +80,16 @@ class ContainerService(
    * Get the URL for an IDE container
    * TODO: make this configurable for different types of hosting/reverse proxies/etc
    */
-  fun getIdeUrl(containerId: String): String {
-    val containerInfo = docker.inspectContainer(containerId)
-    val port = containerInfo.config().labels()!![LABEL_THEIA_PORT]
-
-    return "http://localhost:$port"
+  fun getIdeUrl(answerId: UUID): String {
+    return "$traefikUrl/ide/$answerId/"
   }
 
   /**
    * Try to find an existing container for the given submission
    */
   protected fun getIdeContainer(answer: Answer): String? {
     return docker.listContainers(
-        DockerClient.ListContainersParam.withLabel(LABEL_TASK_SUBMISSION_ID, answer.id.toString()),
+        DockerClient.ListContainersParam.withLabel(LABEL_ANSWER_ID, answer.id.toString()),
         DockerClient.ListContainersParam.limitContainers(1)
     ).firstOrNull()?.id()
   }
@@ -111,26 +108,22 @@ class ContainerService(
    * Returns the ID of the created container
    */
   protected fun createIdeContainer(answer: Answer): String {
-    val id = answer.id.toString()
-
-    // 49152-65535 is the private port range
-    val theiaPort = Random.nextInt(49152, 65535).toString()
-
-    val labelMap = mapOf(
-        LABEL_TASK_SUBMISSION_ID to id,
-        LABEL_THEIA_PORT to theiaPort
+    val answerId = answer.id.toString()
+
+    val labels = mapOf(
+        LABEL_ANSWER_ID to answerId,
+        "traefik.enable" to "true",
+        "traefik.frontend.rule" to "PathPrefixStrip: /ide/$answerId/",
+        "traefik.port" to "3000",
+        "traefik.frontend.headers.customResponseHeaders" to "Access-Control-Allow-Origin:*"
     )
 
-    val publishedPorts = mapOf(
-        "3000" to listOf(PortBinding.of("0.0.0.0", theiaPort))
-    )
-    val hostConfig = HostConfig.builder().portBindings(publishedPorts).build()
+    val hostConfig = HostConfig.builder().build()
 
     val containerConfig = ContainerConfig.builder()
         .image(IDE_DOCKER_IMAGE)
-        .labels(labelMap)
+        .labels(labels)
         .hostConfig(hostConfig)
-        .exposedPorts(publishedPorts.keys)
         .build()
 
     val container = docker.createContainer(containerConfig)

src/main/resources/application.properties

@@ -28,6 +28,8 @@
 
 spring.profiles.active=dev
 
+code-freak.traefik.url=http://localhost:8081
+
 # Hides HHH000424: Disabling contextual LOB creation as createClob() method threw error
 logging.level.org.hibernate.engine.jdbc.env.internal.LobCreatorBuilderImpl = WARN
 

src/main/resources/templates/ide-redirect.html

@@ -11,8 +11,12 @@
       let ide_url = /*[[${ide_url}]]*/
 
       function tryRedirect() {
-        fetch(ide_url, { mode: "no-cors" }).then(function() {
-          window.location.href = ide_url
+        fetch(ide_url).then(function(res) {
+          if (res.ok) {
+            window.location.href = ide_url
+          } else {
+            throw new Error()
+          }
         }).catch(function() {
           setTimeout(tryRedirect, 1000)
         });

src/test/kotlin/de/code_freak/codefreak/service/ContainerServiceTest.kt

@@ -7,10 +7,10 @@ import de.code_freak.codefreak.entity.Answer
 import de.code_freak.codefreak.util.TarUtil
 import org.hamcrest.MatcherAssert.assertThat
 import org.hamcrest.Matchers.containsString
-import org.hamcrest.Matchers.equalTo
 import org.hamcrest.Matchers.hasSize
 import org.hamcrest.Matchers.not
 import org.junit.After
+import org.junit.Assert.assertTrue
 import org.junit.Before
 import org.junit.Test
 import org.mockito.Mockito.`when`
@@ -27,7 +27,7 @@ internal class ContainerServiceTest : SpringTest() {
   @Autowired
   lateinit var containerService: ContainerService
 
-  val taskSubmission by lazy {
+  val answer by lazy {
     val mock = mock(Answer::class.java)
     `when`(mock.id).thenReturn(UUID(0, 0))
     mock
@@ -42,40 +42,44 @@ internal class ContainerServiceTest : SpringTest() {
   @After
   fun tearDown() {
     // delete all containers before and after each run
-    listIdeContainer().parallelStream().forEach {
+    getAllIdeContainers().parallelStream().forEach {
       docker.killContainer(it.id())
       docker.removeContainer(it.id())
     }
   }
 
   @Test
   fun `New IDE container is started`() {
-    val containerId = containerService.startIdeContainer(taskSubmission)
-    val containers = listIdeContainer()
-    assertThat(containers, hasSize(1))
-    assertThat(containers[0].id(), equalTo(containerId))
+    containerService.startIdeContainer(answer)
+    val container = getIdeContainer(answer) // throws if container is not present
+    assertTrue(docker.inspectContainer(container.id()).state().running())
   }
 
   @Test
   fun `Existing IDE container is used`() {
-    val containerId1 = containerService.startIdeContainer(taskSubmission)
-    containerService.startIdeContainer(taskSubmission)
-    val containers = listIdeContainer()
-    assertThat(containers, hasSize(1))
-    assertThat(containers[0].id(), equalTo(containerId1))
+    containerService.startIdeContainer(answer)
+    containerService.startIdeContainer(answer) // start twice for the same answer
+    assertThat(getIdeContainers(answer), hasSize(1))
   }
 
   @Test
   fun `files are extracted to project directory`() {
-    `when`(taskSubmission.files).thenReturn(TarUtil.createTarFromDirectory(ClassPathResource("tasks/c-simple").file))
-    val containerId = containerService.startIdeContainer(taskSubmission)
+    `when`(answer.files).thenReturn(TarUtil.createTarFromDirectory(ClassPathResource("tasks/c-simple").file))
+    containerService.startIdeContainer(answer)
+    val containerId = getIdeContainer(answer).id()
     // assert that file is existing and nothing is owned by root
     val dirContent = containerService.exec(containerId, arrayOf("ls", "-l", "/home/project"))
     assertThat(dirContent, containsString("main.c"))
     assertThat(dirContent, not(containsString("root")))
   }
 
-  private fun listIdeContainer() = docker.listContainers(
-      ListContainersParam.withLabel(ContainerService.LABEL_TASK_SUBMISSION_ID)
+  private fun getAllIdeContainers() = docker.listContainers(
+      ListContainersParam.withLabel(ContainerService.LABEL_ANSWER_ID)
   )
+
+  private fun getIdeContainers(answer: Answer) = docker.listContainers(
+      ListContainersParam.withLabel(ContainerService.LABEL_ANSWER_ID, answer.id.toString())
+  )
+
+  private fun getIdeContainer(answer: Answer) = getIdeContainers(answer).first()
 }