feat: support Chroma HttpClient + per-tenant collection prefix

CONTRIBUTING.md

@@ -5,8 +5,11 @@ Thanks for wanting to help. MemPalace is open source and we welcome contribution
 ## Getting Started
 
 ```bash
-git clone https://github.com/milla-jovovich/mempalace.git
+# Fork the repo on GitHub first, then clone your fork
+git clone https://github.com/<your-username>/mempalace.git
 cd mempalace
+git remote add upstream https://github.com/milla-jovovich/mempalace.git
+
 pip install -e ".[dev]"    # installs with dev dependencies (pytest, build, twine)
 ```
 

hooks/mempal_precompact_hook.sh

@@ -72,6 +72,6 @@ fi
 cat << 'HOOKJSON'
 {
   "decision": "block",
-  "reason": "COMPACTION IMMINENT. Save ALL topics, decisions, quotes, code, and important context from this session to your memory system. Be thorough — after compaction, detailed context will be lost. Organize into appropriate categories. Use verbatim quotes where possible. Save everything, then allow compaction to proceed."
+  "reason": "COMPACTION IMMINENT (MemPalace). Save ALL session content before context is lost:\n1. mempalace_diary_write — thorough AAAK-compressed session summary\n2. mempalace_add_drawer — ALL verbatim quotes, decisions, code, context\n3. mempalace_kg_add — entity relationships (optional)\nBe thorough — after compaction, detailed context will be lost. Do NOT write to Claude Code's native auto-memory (.md files). Save everything to MemPalace, then allow compaction to proceed."
 }
 HOOKJSON

hooks/mempal_save_hook.sh

@@ -145,7 +145,7 @@ if [ "$SINCE_LAST" -ge "$SAVE_INTERVAL" ] && [ "$EXCHANGE_COUNT" -gt 0 ]; then
     cat << 'HOOKJSON'
 {
   "decision": "block",
-  "reason": "AUTO-SAVE checkpoint. Save key topics, decisions, quotes, and code from this session to your memory system. Organize into appropriate categories. Use verbatim quotes where possible. Continue conversation after saving."
+  "reason": "AUTO-SAVE checkpoint (MemPalace). Save this session's key content:\n1. mempalace_diary_write — AAAK-compressed session summary\n2. mempalace_add_drawer — verbatim quotes, decisions, code snippets\n3. mempalace_kg_add — entity relationships (optional)\nDo NOT write to Claude Code's native auto-memory (.md files). Continue conversation after saving."
 }
 HOOKJSON
 else

mempalace/cli.py

@@ -34,6 +34,7 @@
 from pathlib import Path
 
 from .config import MempalaceConfig
+from mempalace.config import get_chroma_client, get_collection_name
 
 
 def cmd_init(args):
@@ -183,8 +184,8 @@ def cmd_repair(args):
 
     # Try to read existing drawers
     try:
-        client = chromadb.PersistentClient(path=palace_path)
-        col = client.get_collection("mempalace_drawers")
+        client = get_chroma_client()
+        col = client.get_collection(get_collection_name())
         total = col.count()
         print(f"  Drawers found: {total}")
     except Exception as e:
@@ -295,8 +296,8 @@ def cmd_compress(args):
 
     # Connect to palace
     try:
-        client = chromadb.PersistentClient(path=palace_path)
-        col = client.get_collection("mempalace_drawers")
+        client = get_chroma_client()
+        col = client.get_collection(get_collection_name())
     except Exception:
         print(f"\n  No palace found at {palace_path}")
         print("  Run: mempalace init <dir> then mempalace mine <dir>")

mempalace/config.py

@@ -9,6 +9,8 @@
 import re
 from pathlib import Path
 
+import chromadb
+
 
 # ── Input validation ──────────────────────────────────────────────────────────
 # Shared sanitizers for wing/room/entity names. Prevents path traversal,
@@ -57,10 +59,38 @@ def sanitize_content(value: str, max_length: int = 100_000) -> str:
         raise ValueError("content contains null bytes")
     return value
 
-
 DEFAULT_PALACE_PATH = os.path.expanduser("~/.mempalace/palace")
 DEFAULT_COLLECTION_NAME = "mempalace_drawers"
 
+# --- Multi-tenant Chroma HttpClient support (mpc-multi-tenant patch) --------
+
+_chroma_client_cache = None
+
+
+def get_chroma_client(config=None):
+    """Return a cached chromadb.HttpClient for the shared Chroma Server."""
+    global _chroma_client_cache
+    if _chroma_client_cache is not None:
+        return _chroma_client_cache
+    if config is None:
+        config = MempalaceConfig()
+    _chroma_client_cache = chromadb.HttpClient(
+        host=config.chroma_http_host,
+        port=config.chroma_http_port,
+    )
+    return _chroma_client_cache
+
+
+def get_collection_name(config=None, suffix=None):
+    """Return the tenant-scoped collection name (e.g., 'tenant_<uuid>_mempalace_drawers')."""
+    if config is None:
+        config = MempalaceConfig()
+    base = suffix or config.collection_name
+    prefix = config.collection_prefix
+    if prefix:
+        return f"{prefix}_{base}"
+    return base
+
 DEFAULT_TOPIC_WINGS = [
     "emotions",
     "consciousness",
@@ -152,6 +182,32 @@ def collection_name(self):
         """ChromaDB collection name."""
         return self._file_config.get("collection_name", DEFAULT_COLLECTION_NAME)
 
+    @property
+    def chroma_http_host(self):
+        """Chroma Server hostname (default: localhost)."""
+        return os.environ.get("MEMPALACE_CHROMA_HOST") or self._file_config.get(
+            "chroma_http_host", "localhost"
+        )
+
+    @property
+    def chroma_http_port(self):
+        """Chroma Server port (default: 8000)."""
+        v = os.environ.get("MEMPALACE_CHROMA_PORT") or self._file_config.get(
+            "chroma_http_port", 8000
+        )
+        return int(v)
+
+    @property
+    def collection_prefix(self):
+        """Per-tenant collection name prefix (e.g., 'tenant_<uuid>').
+
+        Set by the sidecar per-request via MEMPALACE_COLLECTION_PREFIX.
+        When empty, collection names are unprefixed (single-user mode).
+        """
+        return os.environ.get("MEMPALACE_COLLECTION_PREFIX") or self._file_config.get(
+            "collection_prefix", ""
+        )
+
     @property
     def people_map(self):
         """Mapping of name variants to canonical names."""

mempalace/hooks_cli.py

@@ -18,18 +18,22 @@
 STATE_DIR = Path.home() / ".mempalace" / "hook_state"
 
 STOP_BLOCK_REASON = (
-    "AUTO-SAVE checkpoint. Save key topics, decisions, quotes, and code "
-    "from this session to your memory system. Organize into appropriate "
-    "categories. Use verbatim quotes where possible. Continue conversation "
-    "after saving."
+    "AUTO-SAVE checkpoint (MemPalace). Save this session's key content:\n"
+    "1. mempalace_diary_write — AAAK-compressed session summary\n"
+    "2. mempalace_add_drawer — verbatim quotes, decisions, code snippets\n"
+    "3. mempalace_kg_add — entity relationships (optional)\n"
+    "Do NOT write to Claude Code's native auto-memory (.md files). "
+    "Continue conversation after saving."
 )
 
 PRECOMPACT_BLOCK_REASON = (
-    "COMPACTION IMMINENT. Save ALL topics, decisions, quotes, code, and "
-    "important context from this session to your memory system. Be thorough "
-    "\u2014 after compaction, detailed context will be lost. Organize into "
-    "appropriate categories. Use verbatim quotes where possible. Save "
-    "everything, then allow compaction to proceed."
+    "COMPACTION IMMINENT (MemPalace). Save ALL session content before context is lost:\n"
+    "1. mempalace_diary_write — thorough AAAK-compressed session summary\n"
+    "2. mempalace_add_drawer — ALL verbatim quotes, decisions, code, context\n"
+    "3. mempalace_kg_add — entity relationships (optional)\n"
+    "Be thorough \u2014 after compaction, detailed context will be lost. "
+    "Do NOT write to Claude Code's native auto-memory (.md files). "
+    "Save everything to MemPalace, then allow compaction to proceed."
 )
 
 

mempalace/layers.py

@@ -24,6 +24,7 @@
 import chromadb
 
 from .config import MempalaceConfig
+from mempalace.config import get_chroma_client, get_collection_name
 
 
 # ---------------------------------------------------------------------------
@@ -91,8 +92,8 @@ def __init__(self, palace_path: str = None, wing: str = None):
     def generate(self) -> str:
         """Pull top drawers from ChromaDB and format as compact L1 text."""
         try:
-            client = chromadb.PersistentClient(path=self.palace_path)
-            col = client.get_collection("mempalace_drawers")
+            client = get_chroma_client()
+            col = client.get_collection(get_collection_name())
         except Exception:
             return "## L1 — No palace found. Run: mempalace mine <dir>"
 
@@ -196,8 +197,8 @@ def __init__(self, palace_path: str = None):
     def retrieve(self, wing: str = None, room: str = None, n_results: int = 10) -> str:
         """Retrieve drawers filtered by wing and/or room."""
         try:
-            client = chromadb.PersistentClient(path=self.palace_path)
-            col = client.get_collection("mempalace_drawers")
+            client = get_chroma_client()
+            col = client.get_collection(get_collection_name())
         except Exception:
             return "No palace found."
 
@@ -260,8 +261,8 @@ def __init__(self, palace_path: str = None):
     def search(self, query: str, wing: str = None, room: str = None, n_results: int = 5) -> str:
         """Semantic search, returns compact result text."""
         try:
-            client = chromadb.PersistentClient(path=self.palace_path)
-            col = client.get_collection("mempalace_drawers")
+            client = get_chroma_client()
+            col = client.get_collection(get_collection_name())
         except Exception:
             return "No palace found."
 
@@ -316,8 +317,8 @@ def search_raw(
     ) -> list:
         """Return raw dicts instead of formatted text."""
         try:
-            client = chromadb.PersistentClient(path=self.palace_path)
-            col = client.get_collection("mempalace_drawers")
+            client = get_chroma_client()
+            col = client.get_collection(get_collection_name())
         except Exception:
             return []
 
@@ -437,8 +438,8 @@ def status(self) -> dict:
 
         # Count drawers
         try:
-            client = chromadb.PersistentClient(path=self.palace_path)
-            col = client.get_collection("mempalace_drawers")
+            client = get_chroma_client()
+            col = client.get_collection(get_collection_name())
             count = col.count()
             result["total_drawers"] = count
         except Exception:

mempalace/mcp_server.py

@@ -26,12 +26,11 @@
 from datetime import datetime
 from pathlib import Path
 
-from .config import MempalaceConfig, sanitize_name, sanitize_content
+from .config import MempalaceConfig, sanitize_name, sanitize_content, get_chroma_client, get_collection_name
 from .version import __version__
 from .query_sanitizer import sanitize_query
 from .searcher import search_memories
 from .palace_graph import traverse, find_tunnels, graph_stats
-import chromadb
 
 from .knowledge_graph import KnowledgeGraph
 
@@ -101,15 +100,11 @@ def _wal_log(operation: str, params: dict, result: dict = None):
         logger.error(f"WAL write failed: {e}")
 
 
-_client_cache = None
-_collection_cache = None
-
-
 def _get_client():
-    """Return a singleton ChromaDB PersistentClient."""
+    """Return a singleton ChromaDB HttpClient via multi-tenant config."""
     global _client_cache
     if _client_cache is None:
-        _client_cache = chromadb.PersistentClient(path=_config.palace_path)
+        _client_cache = get_chroma_client()
     return _client_cache
 
 
@@ -118,10 +113,11 @@ def _get_collection(create=False):
     global _collection_cache
     try:
         client = _get_client()
+        col_name = get_collection_name(_config)
         if create:
-            _collection_cache = client.get_or_create_collection(_config.collection_name)
+            _collection_cache = client.get_or_create_collection(col_name)
         elif _collection_cache is None:
-            _collection_cache = client.get_collection(_config.collection_name)
+            _collection_cache = client.get_collection(col_name)
         return _collection_cache
     except Exception:
         return None

mempalace/miner.py

@@ -15,8 +15,7 @@
 from datetime import datetime
 from collections import defaultdict
 
-import chromadb
-
+from .config import get_chroma_client, get_collection_name
 from .palace import SKIP_DIRS, get_collection, file_already_mined
 
 READABLE_EXTENSIONS = {
@@ -625,8 +624,8 @@ def mine(
 def status(palace_path: str):
     """Show what's been filed in the palace."""
     try:
-        client = chromadb.PersistentClient(path=palace_path)
-        col = client.get_collection("mempalace_drawers")
+        client = get_chroma_client()
+        col = client.get_collection(get_collection_name())
     except Exception:
         print(f"\n  No palace found at {palace_path}")
         print("  Run: mempalace init <dir> then mempalace mine <dir>")

mempalace/palace.py

@@ -5,7 +5,8 @@
 """
 
 import os
-import chromadb
+
+from .config import get_chroma_client, get_collection_name
 
 SKIP_DIRS = {
     ".git",
@@ -34,18 +35,19 @@
 }
 
 
-def get_collection(palace_path: str, collection_name: str = "mempalace_drawers"):
+def get_collection(palace_path: str, collection_name: str = None):
     """Get or create the palace ChromaDB collection."""
     os.makedirs(palace_path, exist_ok=True)
     try:
         os.chmod(palace_path, 0o700)
     except (OSError, NotImplementedError):
         pass
-    client = chromadb.PersistentClient(path=palace_path)
+    client = get_chroma_client()
+    col_name = collection_name or get_collection_name()
     try:
-        return client.get_collection(collection_name)
+        return client.get_collection(col_name)
     except Exception:
-        return client.create_collection(collection_name)
+        return client.create_collection(col_name)
 
 
 def file_already_mined(collection, source_file: str, check_mtime: bool = False) -> bool:

mempalace/palace_graph.py

@@ -19,13 +19,14 @@
 from .config import MempalaceConfig
 
 import chromadb
+from mempalace.config import get_chroma_client, get_collection_name
 
 
 def _get_collection(config=None):
     config = config or MempalaceConfig()
     try:
-        client = chromadb.PersistentClient(path=config.palace_path)
-        return client.get_collection(config.collection_name)
+        client = get_chroma_client()
+        return client.get_collection(get_collection_name(config))
     except Exception:
         return None
 

mempalace/searcher.py

@@ -10,6 +10,7 @@
 from pathlib import Path
 
 import chromadb
+from mempalace.config import get_chroma_client, get_collection_name
 
 logger = logging.getLogger("mempalace_mcp")
 
@@ -24,8 +25,8 @@ def search(query: str, palace_path: str, wing: str = None, room: str = None, n_r
     Optionally filter by wing (project) or room (aspect).
     """
     try:
-        client = chromadb.PersistentClient(path=palace_path)
-        col = client.get_collection("mempalace_drawers")
+        client = get_chroma_client()
+        col = client.get_collection(get_collection_name())
     except Exception:
         print(f"\n  No palace found at {palace_path}")
         print("  Run: mempalace init <dir> then mempalace mine <dir>")
@@ -98,8 +99,8 @@ def search_memories(
     Used by the MCP server and other callers that need data.
     """
     try:
-        client = chromadb.PersistentClient(path=palace_path)
-        col = client.get_collection("mempalace_drawers")
+        client = get_chroma_client()
+        col = client.get_collection(get_collection_name())
     except Exception as e:
         logger.error("No palace found at %s: %s", palace_path, e)
         return {