Enabled slack connector to ingest files and support OAuth (#707)

mateuszkuprowski · Mateusz Kuprowski · cursoragent · web-flow · commit 380509a4fcff · 2026-05-25T13:41:40.000+02:00
Co-authored-by: Mateusz Kuprowski &lt;mateusz@unstructured.io&gt;
Co-authored-by: Cursor &lt;cursoragent@cursor.com&gt;
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,3 +1,13 @@
+## [1.6.4]
+
+### Enhancements
+
+- **feat(slack): support file attachments and OAuth refresh tokens.** Slack indexing now emits file attachment records, downloading uses Slack private file URLs with bearer authentication, and `SlackAccessConfig` accepts `refresh_token` so platform plugin schemas can expose OAuth token rotation settings.
+
+### Fixes
+
+- **fix(slack): guard private file downloads.** Validate Slack private download URLs before sending bearer credentials, refuse redirects that could forward bearer credentials, stream private file downloads to disk, and use a bounded timeout for private file reads.
+
 ## [1.6.3]
 
 ### Enhancements
diff --git a/test/unit/connectors/test_slack.py b/test/unit/connectors/test_slack.py
@@ -0,0 +1,166 @@
+from unittest.mock import Mock
+
+import pytest
+
+from unstructured_ingest.data_types.file_data import (
+    FileData,
+    FileDataSourceMetadata,
+    SourceIdentifiers,
+)
+from unstructured_ingest.error import ValueError as IngestValueError
+from unstructured_ingest.processes.connectors.slack import (
+    PRIVATE_FILE_DOWNLOAD_TIMEOUT_SECONDS,
+    SlackAccessConfig,
+    SlackDownloader,
+    SlackIndexer,
+    SlackIndexerConfig,
+    _NoRedirectHandler,
+)
+
+
+def test_slack_access_config_accepts_refresh_token():
+    config = SlackAccessConfig(token="xoxb-slack-token", refresh_token="xoxe-slack-refresh-token")
+
+    assert config.token == "xoxb-slack-token"
+    assert config.refresh_token == "xoxe-slack-refresh-token"
+
+
+def test_slack_indexer_emits_file_data_for_message_files():
+    client = Mock()
+    client.conversations_history.return_value = [
+        {
+            "messages": [
+                {
+                    "ts": "1710000000.000100",
+                    "text": "Here is the report",
+                    "files": [
+                        {
+                            "id": "F123",
+                            "name": "report.pdf",
+                            "url_private_download": "https://files.slack.com/report.pdf",
+                        }
+                    ],
+                }
+            ]
+        }
+    ]
+    connection_config = Mock()
+    connection_config.get_client.return_value = client
+    indexer = SlackIndexer(
+        index_config=SlackIndexerConfig(channels=["C123"]),
+        connection_config=connection_config,
+    )
+
+    file_data = list(indexer.run())
+
+    assert len(file_data) == 2
+    assert file_data[0].source_identifiers.filename.endswith(".xml")
+    slack_file = file_data[1]
+    assert slack_file.source_identifiers.filename == "F123-report.pdf"
+    assert slack_file.metadata.record_locator == {
+        "type": "file",
+        "channel": "C123",
+        "message_ts": "1710000000.000100",
+        "file_id": "F123",
+    }
+
+
+@pytest.mark.asyncio
+async def test_slack_downloader_downloads_file_attachment(tmp_path, mocker):
+    async_client = Mock()
+    async_client.files_info = mocker.AsyncMock(
+        return_value={
+            "ok": True,
+            "file": {
+                "id": "F123",
+                "name": "report.pdf",
+                "url_private_download": "https://files.slack.com/report.pdf",
+            },
+        }
+    )
+    connection_config = Mock()
+    connection_config.get_async_client.return_value = async_client
+    connection_config.access_config.get_secret_value.return_value.token = "xoxb-slack-token"
+    downloader = SlackDownloader(connection_config=connection_config)
+    file_data = FileData(
+        identifier="F123",
+        connector_type="slack",
+        source_identifiers=SourceIdentifiers(
+            filename="F123-report.pdf",
+            fullpath="F123-report.pdf",
+        ),
+        metadata=FileDataSourceMetadata(
+            record_locator={
+                "type": "file",
+                "channel": "C123",
+                "message_ts": "1710000000.000100",
+                "file_id": "F123",
+            }
+        ),
+    )
+    response = Mock()
+    response.__enter__ = Mock(return_value=response)
+    response.__exit__ = Mock(return_value=None)
+    response.read.side_effect = [b"pdf ", b"bytes", b""]
+    opener = Mock()
+    opener.open.return_value = response
+    build_opener = mocker.patch("urllib.request.build_opener", return_value=opener)
+
+    await downloader._download_file(file_data, tmp_path / "F123-report.pdf")
+
+    assert (tmp_path / "F123-report.pdf").read_bytes() == b"pdf bytes"
+    build_opener.assert_called_once_with(_NoRedirectHandler)
+    opener.open.assert_called_once()
+    request = opener.open.call_args.args[0]
+    assert request.full_url == "https://files.slack.com/report.pdf"
+    assert request.headers["Authorization"] == "Bearer xoxb-slack-token"
+    assert opener.open.call_args.kwargs["timeout"] == PRIVATE_FILE_DOWNLOAD_TIMEOUT_SECONDS
+    assert response.read.call_count > 1
+
+
+def test_slack_private_file_download_rejects_redirects():
+    handler = _NoRedirectHandler()
+
+    with pytest.raises(IngestValueError, match="redirected"):
+        handler.redirect_request(None, None, 302, "Found", {}, "https://example.com/report.pdf")
+
+
+@pytest.mark.asyncio
+async def test_slack_downloader_rejects_non_slack_private_download_url(tmp_path, mocker):
+    async_client = Mock()
+    async_client.files_info = mocker.AsyncMock(
+        return_value={
+            "ok": True,
+            "file": {
+                "id": "F123",
+                "name": "report.pdf",
+                "url_private_download": "https://example.com/report.pdf",
+            },
+        }
+    )
+    connection_config = Mock()
+    connection_config.get_async_client.return_value = async_client
+    connection_config.access_config.get_secret_value.return_value.token = "xoxb-slack-token"
+    downloader = SlackDownloader(connection_config=connection_config)
+    file_data = FileData(
+        identifier="F123",
+        connector_type="slack",
+        source_identifiers=SourceIdentifiers(
+            filename="F123-report.pdf",
+            fullpath="F123-report.pdf",
+        ),
+        metadata=FileDataSourceMetadata(
+            record_locator={
+                "type": "file",
+                "channel": "C123",
+                "message_ts": "1710000000.000100",
+                "file_id": "F123",
+            }
+        ),
+    )
+    build_opener = mocker.patch("urllib.request.build_opener")
+
+    with pytest.raises(IngestValueError, match="files.slack.com"):
+        await downloader._download_file(file_data, tmp_path / "F123-report.pdf")
+
+    build_opener.assert_not_called()
diff --git a/unstructured_ingest/__version__.py b/unstructured_ingest/__version__.py
@@ -1 +1 @@
-__version__ = "1.6.3"  # pragma: no cover
+__version__ = "1.6.4"  # pragma: no cover
diff --git a/unstructured_ingest/processes/connectors/slack.py b/unstructured_ingest/processes/connectors/slack.py
@@ -1,5 +1,11 @@
+import asyncio
+import builtins
 import hashlib
+import re
+import shutil
 import time
+import urllib.parse
+import urllib.request
 import xml.etree.ElementTree as ET
 from dataclasses import dataclass, field
 from datetime import datetime
@@ -34,15 +40,51 @@
 # NOTE: Pagination limit set to the upper end of the recommended range
 # https://api.slack.com/apis/pagination#facts
 PAGINATION_LIMIT = 200
+PRIVATE_FILE_DOWNLOAD_TIMEOUT_SECONDS = 60
+SLACK_PRIVATE_FILE_HOST = "files.slack.com"
 
 CONNECTOR_TYPE = "slack"
 
 
+def _safe_slack_filename(filename: str) -> str:
+    sanitized = re.sub(r"[/\\]+", "_", filename).strip()
+    return sanitized or "slack-file"
+
+
+def _validate_private_download_url(download_url: str) -> str:
+    parsed_url = urllib.parse.urlparse(download_url)
+    hostname = parsed_url.hostname.lower() if parsed_url.hostname else None
+
+    if parsed_url.scheme != "https" or hostname != SLACK_PRIVATE_FILE_HOST:
+        raise ValueError("Slack file download URL must be an HTTPS files.slack.com URL.")
+
+    if parsed_url.username or parsed_url.password:
+        raise ValueError("Slack file download URL must not include credentials.")
+
+    try:
+        port = parsed_url.port
+    except builtins.ValueError as exc:
+        raise ValueError("Slack file download URL has an invalid port.") from exc
+
+    if port not in (None, 443):
+        raise ValueError("Slack file download URL must use the default HTTPS port.")
+
+    return download_url
+
+
+class _NoRedirectHandler(urllib.request.HTTPRedirectHandler):
+    def redirect_request(self, req, fp, code, msg, headers, newurl):  # noqa: D102, ANN001
+        raise ValueError(
+            "Slack file download redirected; refusing to forward bearer authorization."
+        )
+
+
 class SlackAccessConfig(AccessConfig):
     token: str = Field(
         description="Bot token used to access Slack API, must have channels:history scope for the"
         " bot user."
     )
+    refresh_token: Optional[str] = Field(default=None, description="Slack OAuth refresh token.")
 
 
 class SlackConnectionConfig(ConnectionConfig):
@@ -109,6 +151,8 @@ def run(self, **kwargs: Any) -> Generator[FileData, None, None]:
                 messages = conversation_history.get("messages", [])
                 if messages:
                     yield self._messages_to_file_data(messages, channel)
+                    for file_data in self._message_files_to_file_data(messages, channel):
+                        yield file_data
 
     def _messages_to_file_data(
         self,
@@ -142,6 +186,44 @@ def _messages_to_file_data(
             display_name=source_identifiers.fullpath,
         )
 
+    def _message_files_to_file_data(
+        self,
+        messages: list[dict],
+        channel: str,
+    ) -> Generator[FileData, None, None]:
+        for message in messages:
+            message_ts = message.get("ts")
+            for slack_file in message.get("files", []) or []:
+                file_id = slack_file.get("id")
+                if not file_id or not message_ts:
+                    continue
+
+                filename = _safe_slack_filename(
+                    f"{file_id}-{slack_file.get('name') or slack_file.get('title') or file_id}"
+                )
+                identifier_base = f"{channel}-{message_ts}-{file_id}"
+                identifier = hashlib.sha256(identifier_base.encode("utf-8")).hexdigest()
+                source_identifiers = SourceIdentifiers(filename=filename, fullpath=filename)
+                yield FileData(
+                    identifier=identifier,
+                    connector_type=CONNECTOR_TYPE,
+                    source_identifiers=source_identifiers,
+                    metadata=FileDataSourceMetadata(
+                        date_created=(
+                            str(slack_file.get("created")) if slack_file.get("created") else None
+                        ),
+                        date_modified=message_ts,
+                        date_processed=str(time.time()),
+                        record_locator={
+                            "type": "file",
+                            "channel": channel,
+                            "message_ts": message_ts,
+                            "file_id": file_id,
+                        },
+                    ),
+                    display_name=source_identifiers.fullpath,
+                )
+
     @SourceConnectionError.wrap
     def precheck(self) -> None:
         client = self.connection_config.get_client()
@@ -172,7 +254,13 @@ async def run_async(self, file_data: FileData, **kwargs) -> DownloadResponse:
             )
             raise ValueError("Generated invalid download path.")
 
-        await self._download_conversation(file_data, download_path)
+        if (
+            file_data.metadata.record_locator
+            and file_data.metadata.record_locator.get("type") == "file"
+        ):
+            await self._download_file(file_data, download_path)
+        else:
+            await self._download_conversation(file_data, download_path)
         return self.generate_download_response(file_data, download_path)
 
     def is_async(self):
@@ -224,6 +312,42 @@ async def _download_conversation(self, file_data: FileData, download_path: Path)
         download_path.parent.mkdir(exist_ok=True, parents=True)
         conversation_xml.write(download_path, encoding="utf-8", xml_declaration=True)
 
+    async def _download_file(self, file_data: FileData, download_path: Path) -> None:
+        record_locator = file_data.metadata.record_locator
+        if record_locator is None or "file_id" not in record_locator:
+            logger.error(f"Invalid file record locator in metadata: {record_locator}.")
+            raise ValueError("Invalid file record locator.")
+
+        client = self.connection_config.get_async_client()
+        file_info = await client.files_info(file=record_locator["file_id"])
+        if not file_info.get("ok", True):
+            raise ValueError(f"Slack files.info failed: {file_info.get('error')}")
+
+        slack_file = file_info.get("file", {})
+        download_url = slack_file.get("url_private_download") or record_locator.get(
+            "url_private_download"
+        )
+        if not download_url:
+            raise ValueError("Slack file is missing url_private_download.")
+        download_url = _validate_private_download_url(download_url)
+
+        token = self.connection_config.access_config.get_secret_value().token
+        request = urllib.request.Request(
+            download_url,
+            headers={"Authorization": f"Bearer {token}"},
+        )
+        download_path.parent.mkdir(exist_ok=True, parents=True)
+        await asyncio.to_thread(self._download_private_file, request, download_path)
+
+    @staticmethod
+    def _download_private_file(request: urllib.request.Request, download_path: Path) -> None:
+        opener = urllib.request.build_opener(_NoRedirectHandler)
+        with opener.open(
+            request,
+            timeout=PRIVATE_FILE_DOWNLOAD_TIMEOUT_SECONDS,
+        ) as response, download_path.open("wb") as output_file:
+            shutil.copyfileobj(response, output_file)
+
     def _conversation_to_xml(self, conversation: list[list[dict]]) -> ET.ElementTree:
         root = ET.Element("messages")
 

Original file line number	Diff line number	Diff line change
`@@ -1 +1 @@`
`1`		`-__version__ = "1.6.3" # pragma: no cover`
	`1`	`+__version__ = "1.6.4" # pragma: no cover`