[grid] Bundle Redis-backed SessionMap by default

java/src/org/openqa/selenium/grid/BUILD.bazel

@@ -200,6 +200,7 @@ java_binary(
     ],
     runtime_deps = [
         ":grid",
+        "//java/src/org/openqa/selenium/grid/sessionmap/redis",
         artifact("org.slf4j:slf4j-jdk14"),
     ],
 )

java/src/org/openqa/selenium/grid/commands/sessionmaps.txt

@@ -5,14 +5,14 @@ following types of data store.
 
 ## RedisBackedSessionMap
 
-`RedisBackedSessionMap` uses Redis as datastore for key, value store. To start it, run the following command:
+`RedisBackedSessionMap` uses Redis as datastore for key, value store. It is built-in bundled by default, so no `--ext` flag required. To start it, run the following command:
 
 ```
-SESSIONS_IMPLEMENTATION=org.openqa.selenium.grid.sessionmap.redis.RedisBackedSessionMap \
-SESSIONS_SCHEME=redis \
-java -jar selenium.jar \
-  --ext $(coursier fetch -p org.seleniumhq.selenium:selenium-session-map-redis:latest.release) \
-  sessions --sessions-host "<redis_host>" --sessions-port <redis_port>
+java -jar selenium.jar sessions \
+  --sessions-implementation org.openqa.selenium.grid.sessionmap.redis.RedisBackedSessionMap \
+  --sessions-scheme redis \
+  --sessions-host "<redis_host>" \
+  --sessions-port <redis_port>
 ```
 
 ## JdbcBackedSessionMap

java/src/org/openqa/selenium/grid/sessionmap/config/BUILD.bazel

@@ -6,6 +6,7 @@ java_library(
     srcs = glob(["*.java"]),
     visibility = [
         "//java/src/org/openqa/selenium/grid:__subpackages__",
+        "//java/test/org/openqa/selenium/grid/sessionmap/config:__pkg__",
     ],
     deps = [
         "//java:auto-service",

java/src/org/openqa/selenium/grid/sessionmap/config/SessionMapFlags.java

@@ -49,6 +49,21 @@ public class SessionMapFlags implements HasRoles {
   @ConfigValue(section = "sessions", name = "hostname", example = "\"localhost\"")
   private String sessionServerHost;
 
+  @Parameter(
+      names = "--sessions-scheme",
+      description = "URI scheme for the session map server (e.g. \"redis\", \"http\").")
+  @ConfigValue(section = "sessions", name = "scheme", example = "\"redis\"")
+  private String sessionServerScheme;
+
+  @Parameter(
+      names = "--sessions-implementation",
+      description = "Full classname of the non-default session map implementation.")
+  @ConfigValue(
+      section = "sessions",
+      name = "implementation",
+      example = "\"org.openqa.selenium.grid.sessionmap.redis.RedisBackedSessionMap\"")
+  private String sessionMapImplementation;
+
   @Override
   public Set<Role> getRoles() {
     return Collections.singleton(SESSION_MAP_ROLE);

java/src/org/openqa/selenium/grid/sessionmap/redis/RedisBackedSessionMap.java

@@ -188,7 +188,7 @@ public Session get(SessionId id) throws NoSuchSessionException {
               : JSON.toType(rawStereotype, Capabilities.class);
 
       String rawStart = connection.get(startKey(id));
-      Instant start = JSON.toType(rawStart, Instant.class);
+      Instant start = rawStart == null ? Instant.EPOCH : JSON.toType(rawStart, Instant.class);
 
       CAPABILITIES.accept(span, caps);
       CAPABILITIES_EVENT.accept(attributeMap, caps);

java/test/org/openqa/selenium/grid/sessionmap/config/BUILD.bazel

@@ -0,0 +1,15 @@
+load("@rules_jvm_external//:defs.bzl", "artifact")
+load("//java:defs.bzl", "JUNIT5_DEPS", "java_test_suite")
+
+java_test_suite(
+    name = "SmallTests",
+    size = "small",
+    srcs = glob(["*Test.java"]),
+    deps = [
+        "//java/src/org/openqa/selenium/grid/config",
+        "//java/src/org/openqa/selenium/grid/sessionmap/config",
+        artifact("com.beust:jcommander"),
+        artifact("org.junit.jupiter:junit-jupiter-api"),
+        artifact("org.assertj:assertj-core"),
+    ] + JUNIT5_DEPS,
+)

java/test/org/openqa/selenium/grid/sessionmap/config/SessionMapFlagsTest.java

@@ -0,0 +1,69 @@
+// Licensed to the Software Freedom Conservancy (SFC) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The SFC licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package org.openqa.selenium.grid.sessionmap.config;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.beust.jcommander.JCommander;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.openqa.selenium.grid.config.AnnotatedConfig;
+import org.openqa.selenium.grid.config.Config;
+
+class SessionMapFlagsTest {
+
+  private SessionMapFlags flags;
+
+  @BeforeEach
+  void setUp() {
+    flags = new SessionMapFlags();
+  }
+
+  @Test
+  void sessionsSchemeFlagPopulatesConfig() {
+    JCommander.newBuilder().addObject(flags).build().parse("--sessions-scheme", "redis");
+
+    Config config = new AnnotatedConfig(flags);
+
+    assertThat(config.get("sessions", "scheme")).contains("redis");
+  }
+
+  @Test
+  void sessionsImplementationFlagPopulatesConfig() {
+    String impl = "org.openqa.selenium.grid.sessionmap.redis.RedisBackedSessionMap";
+    JCommander.newBuilder().addObject(flags).build().parse("--sessions-implementation", impl);
+
+    Config config = new AnnotatedConfig(flags);
+
+    assertThat(config.get("sessions", "implementation")).contains(impl);
+  }
+
+  @Test
+  void sessionsSchemeIsAbsentWhenFlagNotSet() {
+    Config config = new AnnotatedConfig(flags);
+
+    assertThat(config.get("sessions", "scheme")).isEmpty();
+  }
+
+  @Test
+  void sessionsImplementationIsAbsentWhenFlagNotSet() {
+    Config config = new AnnotatedConfig(flags);
+
+    assertThat(config.get("sessions", "implementation")).isEmpty();
+  }
+}

java/test/org/openqa/selenium/grid/sessionmap/redis/BUILD.bazel

@@ -7,6 +7,9 @@ java_test_suite(
     srcs = glob(["*Test.java"]),
     tags = ["skip-rbe"],
     deps = [
+        "//java/src/org/openqa/selenium/events/local",
+        "//java/src/org/openqa/selenium/grid/config",
+        "//java/src/org/openqa/selenium/grid/sessionmap",
         "//java/src/org/openqa/selenium/grid/sessionmap/redis",
         "//java/src/org/openqa/selenium/remote",
         "//java/test/org/openqa/selenium/remote/tracing:tracing-support",

java/test/org/openqa/selenium/grid/sessionmap/redis/RedisBackedSessionMapTest.java

@@ -19,6 +19,7 @@
 
 import static java.util.UUID.randomUUID;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatNoException;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.openqa.selenium.testing.Safely.safelyCall;
 
@@ -36,6 +37,8 @@
 import org.openqa.selenium.NoSuchSessionException;
 import org.openqa.selenium.events.EventBus;
 import org.openqa.selenium.events.local.GuavaEventBus;
+import org.openqa.selenium.grid.config.Config;
+import org.openqa.selenium.grid.config.MapConfig;
 import org.openqa.selenium.grid.data.Availability;
 import org.openqa.selenium.grid.data.NodeId;
 import org.openqa.selenium.grid.data.NodeRemovedEvent;
@@ -44,6 +47,7 @@
 import org.openqa.selenium.grid.data.SessionClosedEvent;
 import org.openqa.selenium.grid.data.Slot;
 import org.openqa.selenium.grid.data.SlotId;
+import org.openqa.selenium.grid.sessionmap.SessionMap;
 import org.openqa.selenium.remote.SessionId;
 import org.openqa.selenium.remote.tracing.DefaultTestTracer;
 import org.openqa.selenium.remote.tracing.Tracer;
@@ -236,6 +240,77 @@ private Session createSession(URI uri) {
         Instant.now());
   }
 
+  @Test
+  void addReturnsTrue() throws URISyntaxException {
+    Session session = createSession(new URI("http://example.com/foo"));
+    assertThat(sessions.add(session)).isTrue();
+  }
+
+  @Test
+  void getUriThrowsForMalformedUriStoredInRedis() {
+    SessionId id = new SessionId(randomUUID());
+    sessions.getRedisClient().mset(Map.of("session:" + id + ":uri", "not a valid uri"));
+    assertThatThrownBy(() -> sessions.getUri(id))
+        .isInstanceOf(NoSuchSessionException.class)
+        .hasMessageContaining(id.toString());
+  }
+
+  @Test
+  void getSucceedsWhenStartKeyIsMissing() throws URISyntaxException {
+    Session expected = createSession(new URI("http://example.com/foo"));
+    sessions.add(expected);
+    sessions.getRedisClient().del("session:" + expected.getId() + ":start");
+
+    Session seen = sessions.get(expected.getId());
+
+    assertThat(seen.getId()).isEqualTo(expected.getId());
+    assertThat(seen.getUri()).isEqualTo(expected.getUri());
+    assertThat(seen.getStartTime()).isEqualTo(Instant.EPOCH);
+  }
+
+  @Test
+  void removeIsIdempotent() {
+    SessionId id = new SessionId(randomUUID());
+    assertThatNoException().isThrownBy(() -> sessions.remove(id));
+  }
+
+  @Test
+  void removeByUriIsNoOpWhenRedisIsEmpty() throws URISyntaxException {
+    assertThatNoException()
+        .isThrownBy(() -> sessions.removeByUri(new URI("http://example.com/foo")));
+  }
+
+  @Test
+  void nodeRemovedEventIgnoresSlotsWithNullSession() throws URISyntaxException {
+    URI nodeUri = new URI("http://example.com/node");
+    Session activeSession = createSession(nodeUri);
+    sessions.add(activeSession);
+
+    bus.fire(new NodeRemovedEvent(createNodeStatusWithNullSlot(nodeUri, activeSession)));
+
+    assertThatThrownBy(() -> sessions.get(activeSession.getId()))
+        .isInstanceOf(NoSuchSessionException.class);
+  }
+
+  @Test
+  void createFromConfigBuildsWorkingSessionMap() throws URISyntaxException {
+    Config config =
+        new MapConfig(
+            Map.of(
+                "sessions", Map.of("host", redisUri.toString()),
+                "events",
+                    Map.of("implementation", "org.openqa.selenium.events.local.GuavaEventBus")));
+
+    SessionMap sessionMap = RedisBackedSessionMap.create(config);
+    try {
+      Session expected = createSession(new URI("http://example.com/foo"));
+      sessionMap.add(expected);
+      assertThat(((RedisBackedSessionMap) sessionMap).get(expected.getId())).isEqualTo(expected);
+    } finally {
+      ((RedisBackedSessionMap) sessionMap).getRedisClient().close();
+    }
+  }
+
   private org.openqa.selenium.grid.data.NodeStatus createNodeStatus(URI nodeUri, Session session) {
     NodeId nodeId = new NodeId(UUID.randomUUID());
     return new org.openqa.selenium.grid.data.NodeStatus(
@@ -254,4 +329,29 @@ private org.openqa.selenium.grid.data.NodeStatus createNodeStatus(URI nodeUri, S
         "test",
         Map.of());
   }
+
+  private org.openqa.selenium.grid.data.NodeStatus createNodeStatusWithNullSlot(
+      URI nodeUri, Session activeSession) {
+    NodeId nodeId = new NodeId(UUID.randomUUID());
+    return new org.openqa.selenium.grid.data.NodeStatus(
+        nodeId,
+        nodeUri,
+        2,
+        Set.of(
+            new Slot(
+                new SlotId(nodeId, UUID.randomUUID()),
+                new ImmutableCapabilities("browserName", "cheese"),
+                Instant.now(),
+                activeSession),
+            new Slot(
+                new SlotId(nodeId, UUID.randomUUID()),
+                new ImmutableCapabilities("browserName", "cheese"),
+                Instant.now(),
+                null)),
+        Availability.UP,
+        Duration.ofSeconds(30),
+        Duration.ofSeconds(30),
+        "test",
+        Map.of());
+  }
 }