feat(methods): add chat.postMessage example

.github/workflows/test.yml

@@ -12,6 +12,7 @@ jobs:
       matrix:
         showcase:
           - "block-kit"
+          - "methods"
     steps:
       - name: Checkout code
         uses: actions/checkout@v7

README.md

@@ -5,3 +5,4 @@ This collections of examples highlights features of a Slack app in the language
 ## Available demonstration
 
 - **[Block Kit](./block-kit)**: The framework of visual components arranged to create app layouts.
+- **[Methods](./methods)**: Individual Slack Web API method calls with the `slack-api-client`.

methods/.gitignore

@@ -0,0 +1,4 @@
+.classpath
+.project
+.settings
+target

methods/README.md

@@ -0,0 +1,21 @@
+# Methods
+
+Individual Slack Web API method calls with the `slack-api-client`.
+
+Read the [docs](https://docs.slack.dev/reference/methods) to explore every method, or explore implementations of specific families.
+
+## What's on display
+
+### chat
+
+- **[chat.postMessage](https://docs.slack.dev/reference/methods/chat.postmessage)**: Sends a message to a channel. [Implementation](./src/main/java/chat/ChatPostMessage.java). Scopes: `chat:write`.
+
+## Running an example
+
+Set a bot token and run an example class directly:
+
+```sh
+export SLACK_TOKEN="xoxb-your-token"
+mvn compile exec:java -Dexec.mainClass=chat.ChatPostMessage
+```
+

methods/pom.xml

@@ -0,0 +1,81 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>com.slack.api</groupId>
+  <artifactId>methods-examples</artifactId>
+  <version>0.1-SNAPSHOT</version>
+  <packaging>jar</packaging>
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.15.0</version>
+        <configuration>
+          <release>17</release>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>com.diffplug.spotless</groupId>
+        <artifactId>spotless-maven-plugin</artifactId>
+        <version>3.7.0</version>
+        <configuration>
+          <formats>
+            <format>
+              <includes>
+                <include>.gitignore</include>
+              </includes>
+              <trimTrailingWhitespace/>
+              <endWithNewline/>
+              <indent>
+                <tabs>true</tabs>
+                <spacesPerTab>4</spacesPerTab>
+              </indent>
+            </format>
+          </formats>
+          <java>
+            <palantirJavaFormat/>
+          </java>
+          <pom/>
+          <markdown>
+            <includes>
+              <include>**/*.md</include>
+            </includes>
+            <flexmark/>
+          </markdown>
+        </configuration>
+        <executions>
+          <execution>
+            <goals>
+              <goal>apply</goal>
+            </goals>
+            <phase>compile</phase>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+    <dependency>
+      <groupId>com.slack.api</groupId>
+      <artifactId>slack-api-client</artifactId>
+      <version>1.49.0</version>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>6.1.0</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.squareup.okhttp3</groupId>
+      <artifactId>mockwebserver</artifactId>
+      <version>4.12.0</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+</project>

methods/src/main/java/chat/ChatPostMessage.java

@@ -0,0 +1,38 @@
+package chat;
+
+import com.slack.api.Slack;
+import com.slack.api.methods.MethodsClient;
+import com.slack.api.methods.SlackApiException;
+import com.slack.api.methods.request.chat.ChatPostMessageRequest;
+import com.slack.api.methods.response.chat.ChatPostMessageResponse;
+import java.io.IOException;
+
+/**
+ * Sends a message to a channel with the chat.postMessage method.
+ * {@link https://docs.slack.dev/reference/methods/chat.postmessage}
+ */
+public class ChatPostMessage {
+
+    public static ChatPostMessageResponse example01(Slack slack) throws IOException, SlackApiException {
+        // Read a token from the environment variables
+        String token = System.getenv("SLACK_TOKEN");
+
+        // Initialize an API Methods client with the given token
+        MethodsClient methods = slack.methods(token);
+
+        // Build a request object
+        ChatPostMessageRequest request = ChatPostMessageRequest.builder()
+                .channel("C123ABC456")
+                .text("Here's a message for you")
+                .build();
+
+        // Get a response as a Java object
+        ChatPostMessageResponse response = methods.chatPostMessage(request);
+
+        return response;
+    }
+
+    public static void main(String[] args) throws IOException, SlackApiException {
+        System.out.println(example01(Slack.getInstance()));
+    }
+}

methods/src/test/java/chat/ChatPostMessageTest.java

@@ -0,0 +1,51 @@
+package chat;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import com.slack.api.Slack;
+import com.slack.api.SlackConfig;
+import com.slack.api.methods.response.chat.ChatPostMessageResponse;
+import java.net.URLDecoder;
+import java.nio.charset.StandardCharsets;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+import okhttp3.mockwebserver.RecordedRequest;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class ChatPostMessageTest {
+
+    MockWebServer server;
+    Slack slack;
+
+    @BeforeEach
+    public void setup() throws Exception {
+        server = new MockWebServer();
+        server.start();
+        SlackConfig config = new SlackConfig();
+        config.setMethodsEndpointUrlPrefix(server.url("/api/").toString());
+        slack = Slack.getInstance(config);
+    }
+
+    @AfterEach
+    public void tearDown() throws Exception {
+        server.shutdown();
+    }
+
+    @Test
+    public void sends() throws Exception {
+        server.enqueue(new MockResponse().setBody("{\"ok\":true}"));
+
+        ChatPostMessageResponse response = ChatPostMessage.example01(slack);
+        assertTrue(response.isOk());
+
+        RecordedRequest request = server.takeRequest();
+        assertEquals("/api/chat.postMessage", request.getPath());
+
+        String body = URLDecoder.decode(request.getBody().readUtf8(), StandardCharsets.UTF_8);
+        assertTrue(body.contains("channel=C123ABC456"));
+        assertTrue(body.contains("text=Here's a message for you"));
+    }
+}