Discord has a webhook limit of 2k chars

changelog/changelog.py

@@ -135,12 +135,25 @@ def main():
         except ValueError as e:
             sys.stderr.write(f"Error calculating 2-week fallback date: {e}\n")
 
-    for i in issues:
-        line = "* {name} (#{id})".format(name=i["title"], id=i["id"])
-        # print to stdout (captured by workflow)
-        print(line)
-        # log to stderr (visible in build logs)
-        debug(f"Outputting: {line}")
+    # Discord limit is 2000. We reserve 300 chars for the header/mentions in the YAML.
+    MAX_CHARS = 1700
+    current_length = 0
+
+    for index, i in enumerate(issues):
+            line = "* {name} (#{id})".format(name=i["title"], id=i["id"])
+            line_len = len(line) + 1  # +1 for the newline character
+            
+            # Check if adding this line would exceed the limit
+            if current_length + line_len > MAX_CHARS:
+                remaining = len(issues) - index
+                truncation_msg = f"\n... (and {remaining} more issues truncated)"
+                print(truncation_msg)
+                debug(f"Truncating output. Hit character limit. {remaining} issues hidden.")
+                break
+                
+            print(line)
+            current_length += line_len
+            debug(f"Outputting: {line}")
 
 if __name__ == "__main__":
     main()