Ele 4029 slack message blocks

elementary/messages/formats/adaptive_cards.py

@@ -16,23 +16,9 @@
     TextBlock,
     TextStyle,
 )
+from elementary.messages.formats.html import ICON_TO_HTML
 from elementary.messages.message_body import Color, MessageBlock, MessageBody
 
-ICON_TO_HTML = {
-    Icon.RED_TRIANGLE: "🔺",
-    Icon.X: "❌",
-    Icon.WARNING: "⚠️",
-    Icon.EXCLAMATION: "❗",
-    Icon.CHECK: "✅",
-    Icon.MAGNIFYING_GLASS: "🔎",
-    Icon.HAMMER_AND_WRENCH: "🛠️",
-    Icon.POLICE_LIGHT: "🚨",
-    Icon.INFO: "ℹ️",
-    Icon.EYE: "👁️",
-    Icon.GEAR: "⚙️",
-    Icon.BELL: "🔔",
-}
-
 COLOR_TO_STYLE = {
     Color.RED: "Attention",
     Color.YELLOW: "Warning",

elementary/messages/formats/block_kit.py

@@ -0,0 +1,231 @@
+from typing import Any, Dict, List, Optional, Tuple
+
+from slack_sdk.models import blocks as slack_blocks
+
+from elementary.messages.blocks import (
+    CodeBlock,
+    DividerBlock,
+    ExpandableBlock,
+    FactBlock,
+    FactListBlock,
+    HeaderBlock,
+    Icon,
+    IconBlock,
+    InlineBlock,
+    LineBlock,
+    LinesBlock,
+    LinkBlock,
+    TextBlock,
+    TextStyle,
+)
+from elementary.messages.formats.html import ICON_TO_HTML
+from elementary.messages.message_body import Color, MessageBlock, MessageBody
+
+COLOR_MAP = {
+    Color.RED: "#ff0000",
+    Color.YELLOW: "#ffcc00",
+    Color.GREEN: "#33b989",
+}
+
+
+class BlockKitBuilder:
+    _SECONDARY_FACT_CHUNK_SIZE = 2
+    _LONGEST_MARKDOWN_SUFFIX_LEN = 3  # length of markdown's code suffix (```)
+
+    def __init__(self) -> None:
+        self._blocks: List[dict] = []
+        self._attachment_blocks: List[dict] = []
+        self._is_divided = False
+
+    def _format_icon(self, icon: Icon) -> str:
+        return ICON_TO_HTML[icon]
+
+    def _format_text_block(self, block: TextBlock) -> str:
+        if block.style == TextStyle.BOLD:
+            return f"*{block.text}*"
+        elif block.style == TextStyle.ITALIC:
+            return f"_{block.text}_"
+        else:
+            return block.text
+
+    def _format_inline_block(self, block: InlineBlock) -> str:
+        if isinstance(block, IconBlock):
+            return self._format_icon(block.icon)
+        elif isinstance(block, TextBlock):
+            return self._format_text_block(block)
+        elif isinstance(block, LinkBlock):
+            return f"<{block.url}|{block.text}>"
+        else:
+            raise ValueError(f"Unsupported inline block type: {type(block)}")
+
+    def _format_line_block_text(self, block: LineBlock) -> str:
+        return block.sep.join(
+            [self._format_inline_block(inline) for inline in block.inlines]
+        )
+
+    def _format_markdown_section_text(self, text: str) -> dict:
+        if len(text) > slack_blocks.SectionBlock.text_max_length:
+            text = (
+                text[
+                    : slack_blocks.SectionBlock.text_max_length
+                    - len("...")
+                    - self._LONGEST_MARKDOWN_SUFFIX_LEN
+                ]
+                + "..."
+                + text[-self._LONGEST_MARKDOWN_SUFFIX_LEN :]
+            )
+        return {
+            "type": "mrkdwn",
+            "text": text,
+        }
+
+    def _format_markdown_section(self, text: str) -> dict:
+        return {
+            "type": "section",
+            "text": self._format_markdown_section_text(text),
+        }
+
+    def _add_block(self, block: dict) -> None:
+        if not self._is_divided:
+            self._blocks.append(block)
+        else:
+            self._attachment_blocks.append(block)
+
+    def _add_lines_block(self, block: LinesBlock) -> None:
+        formatted_lines = [
+            self._format_line_block_text(line_block) for line_block in block.lines
+        ]
+        self._add_block(self._format_markdown_section("\n".join(formatted_lines)))
+
+    def _add_header_block(self, block: HeaderBlock) -> None:
+        if len(block.text) > slack_blocks.HeaderBlock.text_max_length:
+            text = block.text[: slack_blocks.HeaderBlock.text_max_length - 3] + "..."
+        else:
+            text = block.text
+        self._add_block(
+            {
+                "type": "header",
+                "text": {
+                    "type": "plain_text",
+                    "text": text,
+                },
+            }
+        )
+
+    def _add_code_block(self, block: CodeBlock) -> None:
+        self._add_block(self._format_markdown_section(f"```{block.text}```"))
+
+    def _add_primary_fact(self, fact: FactBlock) -> None:
+        self._add_block(
+            self._format_markdown_section(
+                f"*{self._format_line_block_text(fact.title)}*\n{self._format_line_block_text(fact.value)}"
+            )
+        )
+
+    def _add_secondary_facts(self, facts: List[FactBlock]) -> None:
+        if not facts:
+            return
+        self._add_block(
+            {
+                "type": "section",
+                "fields": [
+                    self._format_markdown_section_text(
+                        f"*{self._format_line_block_text(fact.title)}*\n{self._format_line_block_text(fact.value)}"
+                    )
+                    for fact in facts
+                ],
+            }
+        )
+
+    def _add_fact_list_block(self, block: FactListBlock) -> None:
+        remaining_facts = block.facts[:]
+        secondary_facts: List[FactBlock] = []
+        while remaining_facts:
+            current_fact = remaining_facts.pop(0)
+            if current_fact.primary:
+                self._add_secondary_facts(secondary_facts)
+                secondary_facts = []
+                self._add_primary_fact(current_fact)
+            else:
+                if len(secondary_facts) >= self._SECONDARY_FACT_CHUNK_SIZE:
+                    self._add_secondary_facts(secondary_facts)
+                    secondary_facts = []
+                secondary_facts.append(current_fact)
+        self._add_secondary_facts(secondary_facts)
+
+    def _add_divider_block(self, block: DividerBlock) -> None:
+        self._add_block({"type": "divider"})
+        self._is_divided = True
+
+    def _add_expandable_block(self, block: ExpandableBlock) -> None:
+        """
+        Expandable blocks are not supported in Slack Block Kit.
+        However, slack automatically collapses a large section block into an expandable block.
+        """
+        self._add_block(
+            {
+                "type": "section",
+                "text": self._format_markdown_section_text(f"*{block.title}*"),
+            }
+        )
+        self._add_message_blocks(block.body)
+
+    def _add_message_block(self, block: MessageBlock) -> None:
+        if isinstance(block, HeaderBlock):
+            self._add_header_block(block)
+        elif isinstance(block, CodeBlock):
+            self._add_code_block(block)
+        elif isinstance(block, LinesBlock):
+            self._add_lines_block(block)
+        elif isinstance(block, FactListBlock):
+            self._add_fact_list_block(block)
+        elif isinstance(block, DividerBlock):
+            self._add_divider_block(block)
+        elif isinstance(block, ExpandableBlock):
+            self._add_expandable_block(block)
+        else:
+            raise ValueError(f"Unsupported message block type: {type(block)}")
+
+    def _add_message_blocks(self, blocks: List[MessageBlock]) -> None:
+        for block in blocks:
+            self._add_message_block(block)
+
+    def _get_final_blocks(
+        self, color: Optional[Color]
+    ) -> Tuple[List[dict], List[dict]]:
+        """
+        Slack does not support coloring regular messages, only attachments.
+        Also, regular messages are always displayed in full, while attachments show the first 5 blocks (with a "show more" button).
+        The way we handle this is as follows:
+        - If we have a divider block, everything up to it and including it is a regular message, and everything after it is an attachment.
+        - If we don't have a divider block:
+          - If we have a color, everything is an attachment (in order to always display colored messages).
+          - If we don't have a color, everything is a regular message.
+        """
+        if self._is_divided or not color:
+            return self._blocks, self._attachment_blocks
+        else:
+            return [], self._blocks
+
+    def build(self, message: MessageBody) -> Dict[str, Any]:
+        self._blocks = []
+        self._attachment_blocks = []
+        self._add_message_blocks(message.blocks)
+        color_code = COLOR_MAP.get(message.color) if message.color else None
+        blocks, attachment_blocks = self._get_final_blocks(message.color)
+        built_message = {
+            "blocks": blocks,
+            "attachments": [
+                {
+                    "blocks": attachment_blocks,
+                }
+            ],
+        }
+        if color_code:
+            built_message["attachments"][0]["color"] = color_code
+        return built_message
+
+
+def format_block_kit(message: MessageBody) -> Dict[str, Any]:
+    builder = BlockKitBuilder()
+    return builder.build(message)

elementary/messages/formats/html.py

@@ -0,0 +1,20 @@
+from elementary.messages.blocks import Icon
+
+ICON_TO_HTML = {
+    Icon.RED_TRIANGLE: "🔺",
+    Icon.X: "❌",
+    Icon.WARNING: "⚠️",
+    Icon.EXCLAMATION: "❗",
+    Icon.CHECK: "✅",
+    Icon.MAGNIFYING_GLASS: "🔎",
+    Icon.HAMMER_AND_WRENCH: "🛠️",
+    Icon.POLICE_LIGHT: "🚨",
+    Icon.INFO: "ℹ️",
+    Icon.EYE: "👁️",
+    Icon.GEAR: "⚙️",
+    Icon.BELL: "🔔",
+}
+
+for icon in Icon:
+    if icon not in ICON_TO_HTML:
+        raise RuntimeError(f"No HTML representation for icon {icon}")