fix(migration): improve runner migration and plugin installation feedback

src/langbot/pkg/plugin/connector.py

@@ -23,6 +23,11 @@ from langbot_plugin.api.entities.builtin.pipeline.query import provider_session
 
 from ..core import app
 from . import handler
+from .errors import (
+    PluginRuntimeNotConnectedError,
+    PluginInstallationFailedError,
+    MarketplacePluginVersionNotFoundError,
+)
 from .archive import inspect_plugin_archive_metadata
 from .github import (
     validate_github_plugin_install_info,
@@ -89,8 +94,10 @@ async def _read_httpx_response_limited(
     response: httpx.Response,
     *,
     max_bytes: int,
+    task_context: taskmgr.TaskContext | None = None,
 ) -> bytes:
     content_length = response.headers.get('content-length')
+    declared_size = None
     if content_length is not None:
         try:
             declared_size = int(content_length)
@@ -99,9 +106,16 @@ async def _read_httpx_response_limited(
         if declared_size is not None and declared_size > max_bytes:
             raise ValueError(f'Remote response exceeds the {max_bytes}-byte limit')
 
+    started = time.monotonic()
+    if task_context is not None:
+        task_context.metadata.update(download_current=0, download_total=max(declared_size or 0, 0))
     body = bytearray()
     async for chunk in response.aiter_bytes(chunk_size=64 * 1024):
         body.extend(chunk)
+        if task_context is not None:
+            task_context.metadata.update(
+                download_current=len(body), download_speed=len(body) / max(time.monotonic() - started, 0.001)
+            )
         if len(body) > max_bytes:
             raise ValueError(f'Remote response exceeds the {max_bytes}-byte limit')
     return bytes(body)
@@ -113,14 +127,25 @@ async def _marketplace_get(
     *,
     max_bytes: int,
     allow_not_found: bool = False,
+    task_context: taskmgr.TaskContext | None = None,
 ) -> tuple[int, bytes]:
     async with client.stream('GET', url) as response:
         if allow_not_found and response.status_code == 404:
             return response.status_code, b''
+        if response.is_error:
+            body = await _read_httpx_response_limited(response, max_bytes=min(max_bytes, 64 * 1024))
+            try:
+                payload = json.loads(body)
+            except (ValueError, UnicodeDecodeError):
+                payload = {}
+            # Space currently returns HTTP 500 for a missing plugin release.
+            if isinstance(payload, dict) and str(payload.get('msg', '')).startswith('plugin version not found:'):
+                raise MarketplacePluginVersionNotFoundError('The requested plugin version is not available')
         response.raise_for_status()
         return response.status_code, await _read_httpx_response_limited(
             response,
             max_bytes=max_bytes,
+            task_context=task_context,
         )
 
 
@@ -134,25 +159,6 @@ def _decode_json_object(body: bytes, *, subject: str) -> dict[str, Any]:
     return payload
 
 
-class PluginRuntimeNotConnectedError(RuntimeError):
-    """Raised when plugin runtime operations are requested before connection."""
-
-
-class PluginInstallationFailedError(RuntimeError):
-    """Stable Runtime desired-state failure for one plugin installation."""
-
-    def __init__(
-        self,
-        installation_uuid: str,
-        error_code: str,
-        message: str,
-    ) -> None:
-        self.installation_uuid = installation_uuid
-        self.error_code = error_code
-        self.runtime_message = message
-        super().__init__(f'Plugin installation {installation_uuid} failed [{error_code}]: {message}')
-
-
 class PluginRuntimeConnector(ManagedRuntimeConnector):
     """Plugin runtime connector"""
 
@@ -1654,6 +1660,7 @@ class PluginRuntimeConnector(ManagedRuntimeConnector):
                     client,
                     f'{space_url}/api/v1/marketplace/plugins/download/{plugin_author}/{plugin_name}/{version}',
                     max_bytes=_MARKETPLACE_PLUGIN_DOWNLOAD_MAX_BYTES,
+                    task_context=task_context,
                 )
                 return package, version
 

src/langbot/pkg/plugin/errors.py

@@ -0,0 +1,24 @@
+"""Shared plugin operation errors without runtime or application imports."""
+
+
+class PluginRuntimeNotConnectedError(RuntimeError):
+    """Raised when plugin runtime operations are requested before connection."""
+
+
+class PluginInstallationFailedError(RuntimeError):
+    """Stable Runtime desired-state failure for one plugin installation."""
+
+    def __init__(
+        self,
+        installation_uuid: str,
+        error_code: str,
+        message: str,
+    ) -> None:
+        self.installation_uuid = installation_uuid
+        self.error_code = error_code
+        self.runtime_message = message
+        super().__init__(f'Plugin installation {installation_uuid} failed [{error_code}]: {message}')
+
+
+class MarketplacePluginVersionNotFoundError(ValueError):
+    """The requested release is not available from the marketplace."""