add slack markdown formatting (#2829)

* add slack markdown formatting

* nit

* k

backend/danswer/danswerbot/slack/formatting.py

@@ -0,0 +1,66 @@
+from mistune import Markdown  # type: ignore
+from mistune import Renderer  # type: ignore
+
+
+def format_slack_message(message: str | None) -> str:
+    renderer = Markdown(renderer=SlackRenderer())
+    return renderer.render(message)
+
+
+class SlackRenderer(Renderer):
+    SPECIALS: dict[str, str] = {"&": "&amp;", "<": "&lt;", ">": "&gt;"}
+
+    def escape_special(self, text: str) -> str:
+        for special, replacement in self.SPECIALS.items():
+            text = text.replace(special, replacement)
+        return text
+
+    def header(self, text: str, level: int, raw: str | None = None) -> str:
+        return f"*{text}*\n"
+
+    def emphasis(self, text: str) -> str:
+        return f"_{text}_"
+
+    def double_emphasis(self, text: str) -> str:
+        return f"*{text}*"
+
+    def strikethrough(self, text: str) -> str:
+        return f"~{text}~"
+
+    def list(self, body: str, ordered: bool = True) -> str:
+        lines = body.split("\n")
+        count = 0
+        for i, line in enumerate(lines):
+            if line.startswith("li: "):
+                count += 1
+                prefix = f"{count}. " if ordered else "• "
+                lines[i] = f"{prefix}{line[4:]}"
+        return "\n".join(lines)
+
+    def list_item(self, text: str) -> str:
+        return f"li: {text}\n"
+
+    def link(self, link: str, title: str | None, content: str | None) -> str:
+        escaped_link = self.escape_special(link)
+        if content:
+            return f"<{escaped_link}|{content}>"
+        if title:
+            return f"<{escaped_link}|{title}>"
+        return f"<{escaped_link}>"
+
+    def image(self, src: str, title: str | None, text: str | None) -> str:
+        escaped_src = self.escape_special(src)
+        display_text = title or text
+        return f"<{escaped_src}|{display_text}>" if display_text else f"<{escaped_src}>"
+
+    def codespan(self, text: str) -> str:
+        return f"`{text}`"
+
+    def block_code(self, text: str, lang: str | None) -> str:
+        return f"```\n{text}\n```\n"
+
+    def paragraph(self, text: str) -> str:
+        return f"{text}\n"
+
+    def autolink(self, link: str, is_email: bool) -> str:
+        return link if is_email else self.link(link, None, None)

backend/danswer/danswerbot/slack/handlers/handle_regular_answer.py

@@ -27,6 +27,7 @@ from danswer.danswerbot.slack.blocks import build_follow_up_block
 from danswer.danswerbot.slack.blocks import build_qa_response_blocks
 from danswer.danswerbot.slack.blocks import build_sources_blocks
 from danswer.danswerbot.slack.blocks import get_restate_blocks
+from danswer.danswerbot.slack.formatting import format_slack_message
 from danswer.danswerbot.slack.handlers.utils import send_team_member_message
 from danswer.danswerbot.slack.models import SlackMessageInfo
 from danswer.danswerbot.slack.utils import respond_in_thread
@@ -412,10 +413,11 @@ def handle_regular_answer(
 
     # If called with the DanswerBot slash command, the question is lost so we have to reshow it
     restate_question_block = get_restate_blocks(messages[-1].message, is_bot_msg)
+    formatted_answer = format_slack_message(answer.answer) if answer.answer else None
 
     answer_blocks = build_qa_response_blocks(
         message_id=answer.chat_message_id,
-        answer=answer.answer,
+        answer=formatted_answer,
         quotes=answer.quotes.quotes if answer.quotes else None,
         source_filters=retrieval_info.applied_source_filters,
         time_cutoff=retrieval_info.applied_time_cutoff,

backend/requirements/default.txt

@@ -81,3 +81,4 @@ dropbox==11.36.2
 boto3-stubs[s3]==1.34.133
 ultimate_sitemap_parser==0.5
 stripe==10.12.0
+mistune==0.8.4