feat(block-kit): add context actions block example

block-kit/README.md

@@ -10,6 +10,7 @@ Read the [docs](https://docs.slack.dev/block-kit/) to learn concepts behind thes
 
 - **[Actions](https://docs.slack.dev/reference/block-kit/blocks/actions-block)**: Holds multiple interactive elements. [Implementation](./src/main/java/blocks/Actions.java).
 - **[Context](https://docs.slack.dev/reference/block-kit/blocks/context-block)**: Provides contextual info, which can include both images and text. [Implementation](./src/main/java/blocks/Context.java).
+- **[Context actions](https://docs.slack.dev/reference/block-kit/blocks/context-actions-block)**: Displays interactive elements at the message level. [Implementation](./src/main/java/blocks/ContextActions.java).
 - **[Divider](https://docs.slack.dev/reference/block-kit/blocks/divider-block)**: Visually separates pieces of info inside of a message. [Implementation](./src/main/java/blocks/Divider.java).
 - **[File](https://docs.slack.dev/reference/block-kit/blocks/file-block)**: Displays info about remote files. [Implementation](./src/main/java/blocks/File.java).
 - **[Header](https://docs.slack.dev/reference/block-kit/blocks/header-block)**: Displays a larger-sized text. [Implementation](./src/main/java/blocks/Header.java).

block-kit/src/main/java/blocks/ContextActions.java

@@ -0,0 +1,43 @@
+package blocks;
+
+import com.slack.api.model.block.Blocks;
+import com.slack.api.model.block.ContextActionsBlock;
+import com.slack.api.model.block.composition.BlockCompositions;
+import com.slack.api.model.block.composition.FeedbackButtonObject;
+import com.slack.api.model.block.element.BlockElements;
+import java.util.List;
+
+/**
+ * Displays interactive elements at the message level.
+ * {@link https://docs.slack.dev/reference/block-kit/blocks/context-actions-block/}
+ */
+public class ContextActions {
+    /**
+     * A context actions block with feedback buttons.
+     */
+    public static ContextActionsBlock example01() {
+        ContextActionsBlock block = Blocks.contextActions(
+                c -> c.elements(List.of(BlockElements.feedbackButtons(f -> f.actionId("feedback_buttons_1")
+                        .positiveButton(FeedbackButtonObject.builder()
+                                .text(BlockCompositions.plainText("👍"))
+                                .value("positive_feedback")
+                                .build())
+                        .negativeButton(FeedbackButtonObject.builder()
+                                .text(BlockCompositions.plainText("👎"))
+                                .value("negative_feedback")
+                                .build())))));
+        return block;
+    }
+
+    /**
+     * A context actions block with an icon button.
+     */
+    public static ContextActionsBlock example02() {
+        ContextActionsBlock block =
+                Blocks.contextActions(c -> c.elements(List.of(BlockElements.iconButton(i -> i.icon("trash")
+                        .text(BlockCompositions.plainText("Delete"))
+                        .actionId("delete_button_1")
+                        .value("delete_item")))));
+        return block;
+    }
+}

block-kit/src/test/java/blocks/ContextActionsTest.java

@@ -0,0 +1,66 @@
+package blocks;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.google.gson.JsonParser;
+import com.slack.api.model.block.ContextActionsBlock;
+import com.slack.api.util.json.GsonFactory;
+import org.junit.jupiter.api.Test;
+
+public class ContextActionsTest {
+    @Test
+    public void testExample01() {
+        ContextActionsBlock block = ContextActions.example01();
+        String actual = GsonFactory.createSnakeCase().toJson(block);
+        String expected = """
+            {
+              "type": "context_actions",
+              "elements": [
+                {
+                  "type": "feedback_buttons",
+                  "action_id": "feedback_buttons_1",
+                  "positive_button": {
+                    "text": {
+                      "type": "plain_text",
+                      "text": "👍"
+                    },
+                    "value": "positive_feedback"
+                  },
+                  "negative_button": {
+                    "text": {
+                      "type": "plain_text",
+                      "text": "👎"
+                    },
+                    "value": "negative_feedback"
+                  }
+                }
+              ]
+            }
+            """;
+        assertEquals(JsonParser.parseString(expected), JsonParser.parseString(actual));
+    }
+
+    @Test
+    public void testExample02() {
+        ContextActionsBlock block = ContextActions.example02();
+        String actual = GsonFactory.createSnakeCase().toJson(block);
+        String expected = """
+            {
+              "type": "context_actions",
+              "elements": [
+                {
+                  "type": "icon_button",
+                  "icon": "trash",
+                  "text": {
+                    "type": "plain_text",
+                    "text": "Delete"
+                  },
+                  "action_id": "delete_button_1",
+                  "value": "delete_item"
+                }
+              ]
+            }
+            """;
+        assertEquals(JsonParser.parseString(expected), JsonParser.parseString(actual));
+    }
+}