Remove reaction (#769)

Co-authored-by: Tim Jacomb <[email protected]>
Co-authored-by: stephane <[email protected]>

README.md

@@ -160,6 +160,17 @@ slackResponse.addReaction("thumbsup")
 
 ![image][img-emoji-reaction]
 
+You can remove an emoji reaction to a previously-sent message like this:
+
+Example:
+
+```groovy
+def slackResponse = slackSend(channel: "emoji-demo", message: "Here is the primary message")
+slackResponse.addReaction("thumbsup")
+// ... do some stuff
+slackResponse.removeReaction("thumbsup")
+```
+
 This may only work reliably in channels (as opposed to private messages) due to [limitations in the Slack API](https://api.slack.com/methods/chat.postMessage) (See "Post to an IM channel").
 
 This does not currently work in a situation where Jenkins is restarted between sending the initial message and adding the reaction. If this is something you need, please file an issue.

src/main/java/jenkins/plugins/slack/SlackService.java

@@ -21,5 +21,15 @@ public interface SlackService {
 
     boolean addReaction(String channelId, String timestamp, String emojiName);
 
+    /**
+     * Remove an emoji reaction to a message.
+     * @param channelId - Slack's internal channel id (i.e. what's returned in a `chat.postMessage` response)
+     * @param timestamp - Timestamp identifying the message
+     * @param emojiName - The name of the emoji to add in reaction to the message (no colons)
+     *
+     * @return boolean indicating whether the API request succeeded
+     */
+    boolean removeReaction(String channelId, String timestamp, String emojiName);
+
     String getResponseString();
 }

src/main/java/jenkins/plugins/slack/StandardSlackService.java

@@ -427,6 +427,22 @@ public boolean addReaction(String channelId, String timestamp, String emojiName)
         return postToSlack("reactions.add", json);
     }
 
+    /**
+     * Remove an emoji reaction from a message.
+     */
+    @Override
+    public boolean removeReaction(String channelId, String timestamp, String emojiName) {
+        JSONObject json = SlackReactionRequest.builder()
+                .withChannelId(channelId)
+                .withTimestamp(timestamp)
+                .withEmojiName(emojiName)
+                .build()
+                .getBody();
+
+        logger.fine("Removing reaction:  " + json.toString());
+        return postToSlack("reactions.remove", json);
+    }
+
     private String getTokenToUse(String authTokenCredentialId, String token) {
         if (!StringUtils.isEmpty(authTokenCredentialId)) {
             StringCredentials credentials = CredentialsObtainer.lookupCredentials(authTokenCredentialId);

src/main/java/jenkins/plugins/slack/workflow/SlackResponse.java

@@ -65,4 +65,20 @@ public boolean addReaction(String emojiName) {
 
         return slackService.addReaction(channelId, ts, emojiName);
     }
+
+    /**
+     * Remove an emoji reaction to the message that this `SlackResponse` points to.
+     *
+     * @param emojiName - name of the emoji (no colons), e.g. `thumbsup`
+     *
+     * @return boolean indicating whether the API request succeeded
+     */
+    @Whitelisted
+    public boolean removeReaction(String emojiName) {
+        if (slackService == null) {
+            return false;
+        }
+
+        return slackService.removeReaction(channelId, ts, emojiName);
+    }
 }

src/test/java/jenkins/plugins/slack/SlackNotifierTest.java

@@ -94,6 +94,11 @@ public boolean addReaction(String channelId, String timestamp, String emojiName)
             return response;
         }
 
+        @Override
+        public boolean removeReaction(String channelId, String timestamp, String emojiName) {
+            return response;
+        }
+
         public void setResponse(boolean response) {
             this.response = response;
         }

src/test/java/jenkins/plugins/slack/StandardSlackServiceTest.java

@@ -302,4 +302,20 @@ public void usernameAndNotBotUserReturnsTrue() {
         assertTrue(service.publish("message"));
     }
 
+    @Test
+    public void shouldRemoveAReaction() {
+        StandardSlackServiceStub service = new StandardSlackServiceStub(
+                StandardSlackService.builder()
+                        .withBaseUrl("")
+                        .withTeamDomain("domain")
+                        .withBotUser(true)
+                        .withRoomId("#room1")
+                        .withPopulatedToken("token")
+                        .withUsername("username"));
+        CloseableHttpClientStub httpClientStub = new CloseableHttpClientStub();
+        httpClientStub.setHttpStatus(HttpStatus.SC_OK);
+        service.setHttpClient(httpClientStub);
+        assertTrue(service.removeReaction("#my-room", "12345", "thumbup"));
+    }
+
 }