Add Consul module (#4683)

Co-authored-by: Kevin Wittek <kiview@users.noreply.github.com>

.github/ISSUE_TEMPLATE/bug_report.yaml

@@ -18,6 +18,7 @@ body:
         - Cassandra
         - Clickhouse
         - CockroachDB
+        - Consul
         - Couchbase
         - DB2
         - Dynalite

.github/ISSUE_TEMPLATE/enhancement.yaml

@@ -18,6 +18,7 @@ body:
         - Cassandra
         - Clickhouse
         - CockroachDB
+        - Consul
         - Couchbase
         - DB2
         - Dynalite

.github/ISSUE_TEMPLATE/feature.yaml

@@ -18,6 +18,7 @@ body:
         - Cassandra
         - Clickhouse
         - CockroachDB
+        - Consul
         - Couchbase
         - DB2
         - Dynalite

.github/dependabot.yml

@@ -42,6 +42,11 @@ updates:
     schedule:
       interval: "monthly"
     open-pull-requests-limit: 10
+  - package-ecosystem: "gradle"
+    directory: "/modules/consul"
+    schedule:
+      interval: "monthly"
+    open-pull-requests-limit: 10
   - package-ecosystem: "gradle"
     directory: "/modules/couchbase"
     schedule:

.github/labeler.yml

@@ -15,6 +15,8 @@
   - modules/clickhouse/*
 "modules/cockroachdb":
   - modules/cockroachdb/*
+"modules/consul":
+  - modules/consul/*
 "modules/couchbase":
   - modules/couchbase/*
 "modules/db2":

docs/modules/consul.md

@@ -0,0 +1,36 @@
+# Hashicorp Consul Module
+
+Testcontainers module for [Consul](https://github.com/hashicorp/consul). Consul is a tool for managing key value properties. More information on Consul [here](https://www.consul.io/).
+
+## Usage example
+
+<!--codeinclude-->
+[Running Consul in your Junit tests](../../modules/consul/src/test/java/org/testcontainers/consul/ConsulContainerTest.java)
+<!--/codeinclude-->
+
+## Why Consul in Junit tests?
+
+With the increasing popularity of Consul and config externalization, applications are now needing to source properties from Consul.
+This can prove challenging in the development phase without a running Consul instance readily on hand. This library 
+aims to solve your apps integration testing with Consul. You can also use it to
+test how your application behaves with Consul by writing different test scenarios in Junit.
+
+## Adding this module to your project dependencies
+
+Add the following dependency to your `pom.xml`/`build.gradle` file:
+
+```groovy tab='Gradle'
+testImplementation "org.testcontainers:consul:{{latest_version}}"
+```
+
+```xml tab='Maven'
+<dependency>
+    <groupId>org.testcontainers</groupId>
+    <artifactId>consul</artifactId>
+    <version>{{latest_version}}</version>
+    <scope>test</scope>
+</dependency>
+```
+
+See [AUTHORS](https://raw.githubusercontent.com/testcontainers/testcontainers-java/master/modules/consul/AUTHORS) for contributors.
+

mkdocs.yml

@@ -66,6 +66,7 @@ nav:
                 - modules/databases/tidb.md
                 - modules/databases/trino.md
           - modules/azure.md
+          - modules/consul.md
           - modules/docker_compose.md
           - modules/elasticsearch.md
           - modules/gcloud.md

modules/consul/build.gradle

@@ -0,0 +1,9 @@
+description = "Testcontainers :: Consul"
+
+dependencies {
+    api project(':testcontainers')
+
+    testImplementation 'com.ecwid.consul:consul-api:1.4.5'
+    testImplementation 'io.rest-assured:rest-assured:4.4.0'
+    testImplementation 'org.assertj:assertj-core:3.21.0'
+}

modules/consul/src/main/java/org/testcontainers/consul/ConsulContainer.java

@@ -0,0 +1,100 @@
+package org.testcontainers.consul;
+
+import com.github.dockerjava.api.command.InspectContainerResponse;
+import com.github.dockerjava.api.model.Capability;
+import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.containers.wait.strategy.Wait;
+import org.testcontainers.utility.DockerImageName;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * Testcontainers implementation for Consul.
+ */
+public class ConsulContainer extends GenericContainer<ConsulContainer> {
+
+    private static final DockerImageName DEFAULT_IMAGE_NAME = DockerImageName.parse("consul");
+
+    private static final int CONSUL_HTTP_PORT = 8500;
+
+    private static final int CONSUL_GRPC_PORT = 8502;
+
+    private List<String> initCommands = new ArrayList<>();
+
+    private String[] startConsulCmd = new String[] { "agent", "-dev", "-client", "0.0.0.0" };
+
+    public ConsulContainer(String dockerImageName) {
+        this(DockerImageName.parse(dockerImageName));
+    }
+
+    public ConsulContainer(final DockerImageName dockerImageName) {
+        super(dockerImageName);
+        dockerImageName.assertCompatibleWith(DEFAULT_IMAGE_NAME);
+
+        // Use the status leader endpoint to verify if consul is running.
+        setWaitStrategy(Wait.forHttp("/v1/status/leader").forPort(CONSUL_HTTP_PORT).forStatusCode(200));
+
+        withCreateContainerCmdModifier(cmd -> cmd.getHostConfig().withCapAdd(Capability.IPC_LOCK));
+        withEnv("CONSUL_ADDR", "http://0.0.0.0:" + CONSUL_HTTP_PORT);
+        withCommand(startConsulCmd);
+        withExposedPorts(CONSUL_HTTP_PORT, CONSUL_GRPC_PORT);
+    }
+
+    @Override
+    protected void containerIsStarted(InspectContainerResponse containerInfo) {
+        runConsulCommands();
+    }
+
+    private void runConsulCommands() {
+        if (!initCommands.isEmpty()) {
+            String commands = initCommands
+                .stream()
+                .map(command -> "consul " + command)
+                .collect(Collectors.joining(" && "));
+            try {
+                ExecResult execResult = this.execInContainer(new String[] { "/bin/sh", "-c", commands });
+                if (execResult.getExitCode() != 0) {
+                    logger()
+                        .error(
+                            "Failed to execute these init commands {}. Exit code {}. Stdout {}. Stderr {}",
+                            initCommands,
+                            execResult.getExitCode(),
+                            execResult.getStdout(),
+                            execResult.getStderr()
+                        );
+                }
+            } catch (IOException | InterruptedException e) {
+                logger()
+                    .error(
+                        "Failed to execute these init commands {}. Exception message: {}",
+                        initCommands,
+                        e.getMessage()
+                    );
+            }
+        }
+    }
+
+    /**
+     * Run consul commands using the consul cli.
+     *
+     * Useful for enableing more secret engines like:
+     * <pre>
+     *     .withConsulCommand("secrets enable pki")
+     *     .withConsulCommand("secrets enable transit")
+     * </pre>
+     * or register specific K/V like:
+     * <pre>
+     *     .withConsulCommand("kv put config/testing1 value123")
+     * </pre>
+     * @param commands The commands to send to the consul cli
+     * @return this
+     */
+    public ConsulContainer withConsulCommand(String... commands) {
+        initCommands.addAll(Arrays.asList(commands));
+        return self();
+    }
+}

modules/consul/src/test/java/org/testcontainers/consul/ConsulContainerTest.java

@@ -0,0 +1,78 @@
+package org.testcontainers.consul;
+
+import com.ecwid.consul.v1.ConsulClient;
+import com.ecwid.consul.v1.Response;
+import com.ecwid.consul.v1.kv.model.GetValue;
+import io.restassured.RestAssured;
+import org.assertj.core.api.Assertions;
+import org.hamcrest.CoreMatchers;
+import org.hamcrest.MatcherAssert;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.testcontainers.containers.GenericContainer;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * This test shows the pattern to use the ConsulContainer @ClassRule for a junit test. It also has tests that ensure
+ * the properties were added correctly by reading from Consul with the CLI and over HTTP.
+ */
+public class ConsulContainerTest {
+
+    @ClassRule
+    public static ConsulContainer consulContainer = new ConsulContainer(ConsulTestImages.CONSUL_IMAGE)
+        .withConsulCommand("kv put config/testing1 value123");
+
+    @Test
+    public void readFirstPropertyPathWithCli() throws IOException, InterruptedException {
+        GenericContainer.ExecResult result = consulContainer.execInContainer("consul", "kv", "get", "config/testing1");
+        final String output = result.getStdout().replaceAll("\\r?\\n", "");
+        MatcherAssert.assertThat(output, CoreMatchers.containsString("value123"));
+    }
+
+    @Test
+    public void readFirstSecretPathOverHttpApi() throws InterruptedException {
+        RestAssured
+            .given()
+            .when()
+            .get("http://" + getHostAndPort() + "/v1/kv/config/testing1")
+            .then()
+            .assertThat()
+            .body(
+                "[0].Value",
+                CoreMatchers.equalTo(Base64.getEncoder().encodeToString("value123".getBytes(StandardCharsets.UTF_8)))
+            );
+    }
+
+    @Test
+    public void writeAndReadMultipleValuesUsingClient() {
+        final ConsulClient consulClient = new ConsulClient(
+            consulContainer.getHost(),
+            consulContainer.getFirstMappedPort()
+        );
+
+        final Map<String, String> properties = new HashMap<>();
+        properties.put("value", "world");
+        properties.put("other_value", "another world");
+
+        // Write operation
+        properties.forEach((key, value) -> {
+            Response<Boolean> writeResponse = consulClient.setKVValue(key, value);
+            Assertions.assertThat(writeResponse.getValue()).isTrue();
+        });
+
+        // Read operation
+        properties.forEach((key, value) -> {
+            Response<GetValue> readResponse = consulClient.getKVValue(key);
+            Assertions.assertThat(readResponse.getValue().getDecodedValue()).isEqualTo(value);
+        });
+    }
+
+    private String getHostAndPort() {
+        return consulContainer.getHost() + ":" + consulContainer.getMappedPort(8500);
+    }
+}

modules/consul/src/test/java/org/testcontainers/consul/ConsulTestImages.java

@@ -0,0 +1,7 @@
+package org.testcontainers.consul;
+
+import org.testcontainers.utility.DockerImageName;
+
+public interface ConsulTestImages {
+    DockerImageName CONSUL_IMAGE = DockerImageName.parse("consul:1.10.12");
+}

modules/consul/src/test/resources/logback-test.xml

@@ -0,0 +1,16 @@
+<configuration>
+
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <!-- encoders are assigned the type
+             ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} %-5level %logger - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT"/>
+    </root>
+
+    <logger name="org.testcontainers" level="DEBUG"/>
+</configuration>