Files
nextcloud-mcp-server/nextcloud_mcp_server/vector/processor.py
T
Chris Coutinho 5a251a99e6 fix: Set is_placeholder=False in processor to fix search filtering
The processor was not setting is_placeholder field when writing real
document chunks to Qdrant. This caused the placeholder filter to exclude
all documents (since None != False), resulting in 0 search results.

Now explicitly sets is_placeholder: False in payload when writing real
indexed chunks, allowing search filters to correctly distinguish between
placeholders and real documents.
2025-11-20 17:15:19 +01:00

448 lines
17 KiB
Python

"""Processor task for vector database synchronization.
Processes documents from stream: fetches content, generates embeddings, stores in Qdrant.
"""
import logging
import time
import uuid
import anyio
from anyio.abc import TaskStatus
from anyio.streams.memory import MemoryObjectReceiveStream
from httpx import HTTPStatusError
from qdrant_client.models import FieldCondition, Filter, MatchValue, PointStruct
from nextcloud_mcp_server.client import NextcloudClient
from nextcloud_mcp_server.config import get_settings
from nextcloud_mcp_server.embedding import get_bm25_service, get_embedding_service
from nextcloud_mcp_server.observability.metrics import (
record_qdrant_operation,
record_vector_sync_processing,
update_vector_sync_queue_size,
)
from nextcloud_mcp_server.observability.tracing import trace_operation
from nextcloud_mcp_server.vector.document_chunker import DocumentChunker
from nextcloud_mcp_server.vector.placeholder import delete_placeholder_point
from nextcloud_mcp_server.vector.qdrant_client import get_qdrant_client
from nextcloud_mcp_server.vector.scanner import DocumentTask
logger = logging.getLogger(__name__)
def assign_page_numbers(chunks, page_boundaries):
"""Assign page numbers to chunks based on page boundaries.
Each chunk gets the page number where most of its content appears.
For chunks spanning multiple pages, assigns the page containing the
majority of the chunk's characters.
Args:
chunks: List of ChunkWithPosition objects
page_boundaries: List of dicts with {page, start_offset, end_offset}
Returns:
None (modifies chunks in place)
"""
if not page_boundaries:
return
for chunk in chunks:
# Find which page(s) this chunk overlaps with
max_overlap = 0
assigned_page = None
for boundary in page_boundaries:
# Calculate overlap between chunk and page
overlap_start = max(chunk.start_offset, boundary["start_offset"])
overlap_end = min(chunk.end_offset, boundary["end_offset"])
overlap = max(0, overlap_end - overlap_start)
# Assign to page with maximum overlap
if overlap > max_overlap:
max_overlap = overlap
assigned_page = boundary["page"]
if assigned_page is not None:
chunk.page_number = assigned_page
async def processor_task(
worker_id: int,
receive_stream: MemoryObjectReceiveStream[DocumentTask],
shutdown_event: anyio.Event,
nc_client: NextcloudClient,
user_id: str,
*,
task_status: TaskStatus = anyio.TASK_STATUS_IGNORED,
):
"""
Process documents from stream concurrently.
Each processor task runs in a loop:
1. Receive document from stream (with timeout)
2. Fetch content from Nextcloud
3. Tokenize and chunk text
4. Generate embeddings (I/O bound - external API)
5. Upload vectors to Qdrant
Multiple processors run concurrently for I/O parallelism.
Args:
worker_id: Worker identifier for logging
receive_stream: Stream to receive documents from
shutdown_event: Event signaling shutdown
nc_client: Authenticated Nextcloud client
user_id: User being processed
task_status: Status object for signaling task readiness
"""
logger.info(f"Processor {worker_id} started")
# Signal that the task has started and is ready
task_status.started()
while not shutdown_event.is_set():
try:
# Get document with timeout (allows checking shutdown)
with anyio.fail_after(1.0):
doc_task = await receive_stream.receive()
# Update queue size metric after receiving
stream_stats = receive_stream.statistics()
update_vector_sync_queue_size(stream_stats.current_buffer_used)
# Process document
await process_document(doc_task, nc_client)
# Update queue size metric after processing
stream_stats = receive_stream.statistics()
update_vector_sync_queue_size(stream_stats.current_buffer_used)
except TimeoutError:
# No documents available, update metric to show empty queue
stream_stats = receive_stream.statistics()
update_vector_sync_queue_size(stream_stats.current_buffer_used)
continue
except anyio.EndOfStream:
# Scanner finished and closed stream, exit gracefully
logger.info(f"Processor {worker_id}: Scanner finished, exiting")
break
except Exception as e:
logger.error(
f"Processor {worker_id} error processing "
f"{doc_task.doc_type}_{doc_task.doc_id}: {e}",
exc_info=True,
)
# Continue to next document (no task_done() needed with streams)
logger.info(f"Processor {worker_id} stopped")
async def process_document(doc_task: DocumentTask, nc_client: NextcloudClient):
"""
Process a single document: fetch, tokenize, embed, store in Qdrant.
Implements retry logic with exponential backoff for transient failures.
Args:
doc_task: Document task to process
nc_client: Authenticated Nextcloud client
"""
start_time = time.time()
logger.debug(
f"Processing {doc_task.doc_type}_{doc_task.doc_id} "
f"for {doc_task.user_id} ({doc_task.operation})"
)
with trace_operation(
"vector_sync.process_document",
attributes={
"vector_sync.operation": "process",
"vector_sync.user_id": doc_task.user_id,
"vector_sync.doc_id": doc_task.doc_id,
"vector_sync.doc_type": doc_task.doc_type,
"vector_sync.doc_operation": doc_task.operation,
},
):
try:
qdrant_client = await get_qdrant_client()
settings = get_settings()
# Handle deletion
if doc_task.operation == "delete":
await qdrant_client.delete(
collection_name=settings.get_collection_name(),
points_selector=Filter(
must=[
FieldCondition(
key="user_id",
match=MatchValue(value=doc_task.user_id),
),
FieldCondition(
key="doc_id",
match=MatchValue(value=doc_task.doc_id),
),
FieldCondition(
key="doc_type",
match=MatchValue(value=doc_task.doc_type),
),
]
),
)
logger.info(
f"Deleted {doc_task.doc_type}_{doc_task.doc_id} for {doc_task.user_id}"
)
# Record successful deletion metrics
duration = time.time() - start_time
record_qdrant_operation("delete", "success")
record_vector_sync_processing(duration, "success")
return
# Handle indexing with retry
max_retries = 3
retry_delay = 1.0
for attempt in range(max_retries):
try:
await _index_document(doc_task, nc_client, qdrant_client)
# Record successful processing metrics
duration = time.time() - start_time
record_qdrant_operation("upsert", "success")
record_vector_sync_processing(duration, "success")
return # Success
except (HTTPStatusError, Exception) as e:
if attempt < max_retries - 1:
logger.warning(
f"Retry {attempt + 1}/{max_retries} for "
f"{doc_task.doc_type}_{doc_task.doc_id}: {e}"
)
await anyio.sleep(retry_delay)
retry_delay *= 2 # Exponential backoff
else:
logger.error(
f"Failed to index {doc_task.doc_type}_{doc_task.doc_id} "
f"after {max_retries} retries: {e}"
)
# Record failed processing metrics
duration = time.time() - start_time
record_qdrant_operation("upsert", "error")
record_vector_sync_processing(duration, "error")
raise
except Exception:
# Catch any other unexpected errors
duration = time.time() - start_time
record_vector_sync_processing(duration, "error")
raise
async def _index_document(
doc_task: DocumentTask, nc_client: NextcloudClient, qdrant_client
):
"""
Index a single document (called by process_document with retry).
Args:
doc_task: Document task to index
nc_client: Authenticated Nextcloud client
qdrant_client: Qdrant client instance
"""
settings = get_settings()
# Fetch document content
if doc_task.doc_type == "note":
document = await nc_client.notes.get_note(int(doc_task.doc_id))
content = f"{document['title']}\n\n{document['content']}"
title = document["title"]
etag = document.get("etag", "")
file_metadata = {} # No file-specific metadata for notes
file_path = None # Notes don't have file paths
elif doc_task.doc_type == "file":
# For files, doc_id is now the numeric file ID, file_path comes from DocumentTask
if not doc_task.file_path:
raise ValueError(
f"File path required for file indexing but not provided (file_id={doc_task.doc_id})"
)
file_path = doc_task.file_path
# Read file content via WebDAV
content_bytes, content_type = await nc_client.webdav.read_file(file_path)
# Use document processor registry to extract text
from nextcloud_mcp_server.document_processors import get_registry
registry = get_registry()
try:
result = await registry.process(
content=content_bytes,
content_type=content_type,
filename=file_path,
)
content = result.text
file_metadata = result.metadata
title = file_metadata.get("title") or file_path.split("/")[-1]
etag = "" # WebDAV read_file doesn't return etag
# Diagnostic: Log page boundary information if available
if "page_boundaries" in file_metadata:
page_boundaries = file_metadata["page_boundaries"]
logger.info(
f"Page boundaries for {file_path}: "
f"{len(page_boundaries)} pages, text length: {len(content)}"
)
# Log first 3 page boundaries for debugging
for boundary in page_boundaries[:3]:
logger.debug(
f" Page {boundary['page']}: "
f"offsets [{boundary['start_offset']}:{boundary['end_offset']}]"
)
# Verify last boundary matches text length
if page_boundaries:
last_boundary = page_boundaries[-1]
if last_boundary["end_offset"] != len(content):
logger.warning(
f"Text length mismatch: content={len(content)}, "
f"last_boundary_end={last_boundary['end_offset']}"
)
else:
logger.debug(f"No page_boundaries in metadata for {file_path}")
except Exception as e:
logger.error(f"Failed to process file {file_path}: {e}")
raise
else:
raise ValueError(f"Unsupported doc_type: {doc_task.doc_type}")
# Tokenize and chunk (using configured chunk size and overlap)
chunker = DocumentChunker(
chunk_size=settings.document_chunk_size,
overlap=settings.document_chunk_overlap,
)
chunks = await chunker.chunk_text(content)
# Assign page numbers to chunks if page boundaries are available (PDFs)
if doc_task.doc_type == "file" and "page_boundaries" in file_metadata:
assign_page_numbers(chunks, file_metadata["page_boundaries"])
# Diagnostic: Verify page number assignment
assigned_count = sum(1 for c in chunks if c.page_number is not None)
logger.info(
f"Assigned page numbers to {assigned_count}/{len(chunks)} chunks "
f"for {file_path}"
)
# Log first 3 chunks to see their page assignments
for i, chunk in enumerate(chunks[:3]):
logger.debug(
f" Chunk {i}: page={chunk.page_number}, "
f"offsets=[{chunk.start_offset}:{chunk.end_offset}]"
)
# Warning if NO page numbers were assigned
if assigned_count == 0:
logger.warning(
f"NO page numbers assigned! "
f"Text length: {len(content)}, "
f"Chunks: {len(chunks)}, "
f"Chunk offset range: [{chunks[0].start_offset}:{chunks[-1].end_offset}], "
f"Page boundaries: {len(file_metadata['page_boundaries'])} pages, "
f"First boundary: {file_metadata['page_boundaries'][0] if file_metadata['page_boundaries'] else 'None'}"
)
# Extract chunk texts for embedding
chunk_texts = [chunk.text for chunk in chunks]
# Generate dense embeddings (I/O bound - external API call)
embedding_service = get_embedding_service()
dense_embeddings = await embedding_service.embed_batch(chunk_texts)
# Generate sparse embeddings (BM25 for keyword matching)
bm25_service = get_bm25_service()
sparse_embeddings = await bm25_service.encode_batch(chunk_texts)
# Prepare Qdrant points
indexed_at = int(time.time())
points = []
for i, (chunk, dense_emb, sparse_emb) in enumerate(
zip(chunks, dense_embeddings, sparse_embeddings)
):
# Generate deterministic UUID for point ID
# Using uuid5 with DNS namespace and combining doc info
point_name = f"{doc_task.doc_type}:{doc_task.doc_id}:chunk:{i}"
point_id = str(uuid.uuid5(uuid.NAMESPACE_DNS, point_name))
points.append(
PointStruct(
id=point_id,
vector={
"dense": dense_emb,
"sparse": sparse_emb,
},
payload={
"user_id": doc_task.user_id,
"doc_id": doc_task.doc_id,
"doc_type": doc_task.doc_type,
"is_placeholder": False, # Real indexed document (not placeholder)
"title": title,
"excerpt": chunk.text[:200],
"indexed_at": indexed_at,
"modified_at": doc_task.modified_at,
"etag": etag,
"chunk_index": i,
"total_chunks": len(chunks),
"chunk_start_offset": chunk.start_offset,
"chunk_end_offset": chunk.end_offset,
"metadata_version": 2, # v2 includes position metadata
# File-specific metadata (PDF, etc.)
**(
{
"file_path": file_path, # Store file path for retrieval
"mime_type": content_type, # From WebDAV response
"file_size": file_metadata.get("file_size"),
"page_number": chunk.page_number,
"page_count": file_metadata.get("page_count"),
"author": file_metadata.get("author"),
"creation_date": file_metadata.get("creation_date"),
"has_images": file_metadata.get("has_images", False),
"image_count": file_metadata.get("image_count", 0),
}
if doc_task.doc_type == "file"
else {}
),
},
)
)
# Delete placeholder before writing real vectors
# This prevents duplicates and cleans up the placeholder state
try:
await delete_placeholder_point(
doc_id=doc_task.doc_id,
doc_type=doc_task.doc_type,
user_id=doc_task.user_id,
)
except Exception as e:
# Log but don't fail indexing if placeholder deletion fails
logger.warning(
f"Failed to delete placeholder for {doc_task.doc_type}_{doc_task.doc_id}: {e}"
)
# Upsert to Qdrant
await qdrant_client.upsert(
collection_name=settings.get_collection_name(),
points=points,
wait=True,
)
logger.info(
f"Indexed {doc_task.doc_type}_{doc_task.doc_id} for {doc_task.user_id} "
f"({len(chunks)} chunks)"
)