Modify list_collections client methods to return a list of collection…

… names

chromadb/api/__init__.py

@@ -31,8 +31,7 @@
 from chromadb.config import Component, Settings
 from chromadb.types import Database, Tenant, Collection as CollectionModel
 import chromadb.utils.embedding_functions as ef
-from chromadb.api.models.Collection import Collection
-
+from chromadb.api.models.Collection import Collection, CollectionName
 
 # Re-export the async version
 from chromadb.api.async_api import (  # noqa: F401
@@ -347,19 +346,19 @@ def list_collections(
         self,
         limit: Optional[int] = None,
         offset: Optional[int] = None,
-    ) -> Sequence[Collection]:
+    ) -> Sequence[CollectionName]:
         """List all collections.
         Args:
             limit: The maximum number of entries to return. Defaults to None.
             offset: The number of entries to skip before returning. Defaults to None.
 
         Returns:
-            Sequence[Collection]: A list of collections
+            Sequence[CollectionName]: A list of collection names
 
         Examples:
             ```python
             client.list_collections()
-            # [collection(name="my_collection", metadata={})]
+            # ["my_collection"]
             ```
         """
         pass

chromadb/api/async_api.py

@@ -338,19 +338,19 @@ async def list_collections(
         self,
         limit: Optional[int] = None,
         offset: Optional[int] = None,
-    ) -> Sequence[AsyncCollection]:
+    ) -> Sequence[str]:
         """List all collections.
         Args:
             limit: The maximum number of entries to return. Defaults to None.
             offset: The number of entries to skip before returning. Defaults to None.
 
         Returns:
-            Sequence[Collection]: A list of collections
+            Sequence[str]: A list of collection names.
 
         Examples:
             ```python
             await client.list_collections()
-            # [collection(name="my_collection", metadata={})]
+            # ["my_collection"]
             ```
         """
         pass

chromadb/api/async_client.py

@@ -2,6 +2,8 @@
 from typing import Optional, Sequence
 from uuid import UUID
 from overrides import override
+
+from chromadb.api.models.Collection import CollectionName
 from chromadb.auth import UserIdentity
 from chromadb.auth.utils import maybe_set_tenant_and_database
 from chromadb.api import AsyncAdminAPI, AsyncClientAPI, AsyncServerAPI
@@ -152,17 +154,11 @@ async def heartbeat(self) -> int:
     @override
     async def list_collections(
         self, limit: Optional[int] = None, offset: Optional[int] = None
-    ) -> Sequence[AsyncCollection]:
+    ) -> Sequence[CollectionName]:
         models = await self._server.list_collections(
             limit, offset, tenant=self.tenant, database=self.database
         )
-        return [
-            AsyncCollection(
-                client=self._server,
-                model=model,
-            )
-            for model in models
-        ]
+        return [CollectionName(model.name) for model in models]
 
     @override
     async def count_collections(self) -> int:

chromadb/api/client.py

@@ -25,7 +25,7 @@
 from chromadb.auth.utils import maybe_set_tenant_and_database
 from chromadb.config import Settings, System
 from chromadb.config import DEFAULT_TENANT, DEFAULT_DATABASE
-from chromadb.api.models.Collection import Collection
+from chromadb.api.models.Collection import Collection, CollectionName
 from chromadb.errors import ChromaError
 from chromadb.types import Database, Tenant, Where, WhereDocument
 import chromadb.utils.embedding_functions as ef
@@ -118,9 +118,9 @@ def heartbeat(self) -> int:
     @override
     def list_collections(
         self, limit: Optional[int] = None, offset: Optional[int] = None
-    ) -> Sequence[Collection]:
+    ) -> Sequence[CollectionName]:
         return [
-            Collection(client=self._server, model=model)
+            CollectionName(model.name)
             for model in self._server.list_collections(
                 limit, offset, tenant=self.tenant, database=self.database
             )

chromadb/api/models/Collection.py

@@ -1,3 +1,4 @@
+import inspect
 from typing import TYPE_CHECKING, Optional, Union
 
 from chromadb.api.models.CollectionCommon import CollectionCommon
@@ -380,3 +381,42 @@ def delete(
             tenant=self.tenant,
             database=self.database,
         )
+
+
+
+class CollectionName(str):
+    """
+    A string wrapper to supply users with indicative message about list_collections only
+    returning collection names, in lieu of Collection object.
+
+    When a user will try to access an attribute on a CollectionName string, the __getattribute__ method
+    of str is invoked first. If a valid str method or property is found, it will be used. Otherwise, the fallback
+    __getattr__ defined here is invoked next. It will error if the requested attribute is a Collection
+    method or property.
+
+    For example:
+    collection_name = client.list_collections()[0] # collection_name = "test"
+
+    collection_name.startsWith("t") # Evaluates to True.
+    # __getattribute__ is invoked first, selecting startsWith from str.
+
+    collection_name.add(ids=[...], documents=[...]) # Raises the error defined below
+    # __getattribute__ is invoked first, not finding a match in str.
+    # __getattr__ from this class is invoked and raises an error
+
+    """
+
+    def __getattr__(self, item):
+        collection_attributes_and_methods = [
+            member for member, _ in inspect.getmembers(Collection)
+            if not member.startswith("_")
+        ]
+
+        if item in collection_attributes_and_methods:
+            raise NotImplementedError(
+                f"In Chroma v0.6.0, list_collections only returns collection names. "
+                f"Use Client.get_collection(collection_name) to access {item}. "
+                f"See https://docs.trychroma.com/deployment/migration for more information."
+            )
+
+        raise AttributeError(f"'CollectionName' object has no attribute '{item}'")

chromadb/cli/cli.py

@@ -154,7 +154,8 @@ def vacuum(
                 sqlite, system.instance(SegmentManager)
             )
 
-            for collection in collections:
+            for collection_name in collections:
+                collection = client.get_collection(collection_name)
                 sqlite.purge_log(collection_id=collection.id)
                 progress.update(task, advance=1)
         except Exception as e:

chromadb/test/client/test_database_tenant.py

@@ -24,32 +24,38 @@ def test_database_tenant_collections(client_factories: ClientFactories) -> None:
     # List collections in the default database
     collections = client.list_collections()
     assert len(collections) == 1
-    assert collections[0].name == "collection"
-    assert collections[0].metadata == {"database": DEFAULT_DATABASE}
+    assert collections[0] == "collection"
+    collection = client.get_collection(collections[0])
+    assert collection.metadata == {"database": DEFAULT_DATABASE}
 
     # List collections in the new database
     client.set_tenant(tenant=DEFAULT_TENANT, database="test_db")
     collections = client.list_collections()
     assert len(collections) == 1
-    assert collections[0].metadata == {"database": "test_db"}
+    collection = client.get_collection(collections[0])
+    assert collection.metadata == {"database": "test_db"}
 
     # Update the metadata in both databases to different values
     client.set_tenant(tenant=DEFAULT_TENANT, database=DEFAULT_DATABASE)
-    client.list_collections()[0].modify(metadata={"database": "default2"})
+    collection = client.get_collection(client.list_collections()[0])
+    collection.modify(metadata={"database": "default2"})
 
     client.set_tenant(tenant=DEFAULT_TENANT, database="test_db")
-    client.list_collections()[0].modify(metadata={"database": "test_db2"})
+    collection = client.get_collection(client.list_collections()[0])
+    collection.modify(metadata={"database": "test_db2"})
 
     # Validate that the metadata was updated
     client.set_tenant(tenant=DEFAULT_TENANT, database=DEFAULT_DATABASE)
     collections = client.list_collections()
     assert len(collections) == 1
-    assert collections[0].metadata == {"database": "default2"}
+    collection = client.get_collection(collections[0])
+    assert collection.metadata == {"database": "default2"}
 
     client.set_tenant(tenant=DEFAULT_TENANT, database="test_db")
     collections = client.list_collections()
     assert len(collections) == 1
-    assert collections[0].metadata == {"database": "test_db2"}
+    collection = client.get_collection(collections[0])
+    assert collection.metadata == {"database": "test_db2"}
 
     # Delete the collections and make sure databases are isolated
     client.set_tenant(tenant=DEFAULT_TENANT, database=DEFAULT_DATABASE)

chromadb/test/client/test_multiple_clients_concurrency.py

@@ -44,6 +44,7 @@ def run_target(n: int) -> None:
         client.set_database(database)
         seen_collections = client.list_collections()
         assert len(seen_collections) == COLLECTION_COUNT
-        for collection in seen_collections:
+        for collection_name in seen_collections:
+            collection = client.get_collection(collection_name)
             assert collection.name in collections
             assert collection.metadata == {"database": database}

chromadb/test/property/test_collections.py

@@ -88,8 +88,8 @@ def delete_coll(self, coll: strategies.ExternalCollection) -> None:
     def list_collections(self) -> None:
         colls = self.client.list_collections()
         assert len(colls) == len(self.model)
-        for c in colls:
-            assert c.name in self.model
+        for collection_name in colls:
+            assert collection_name in self.model
 
     # @rule for list_collections with limit and offset
     @rule(

chromadb/test/test_api.py

@@ -485,7 +485,8 @@ def test_metadata_cru(client):
 
     # Test list collections
     collections = client.list_collections()
-    for collection in collections:
+    for collection_name in collections:
+        collection = client.get_collection(collection_name)
         if collection.name == "testspace":
             assert collection.metadata is not None
             assert collection.metadata["a"] == 2

docs/docs.trychroma.com/pages/deployment/migration.md

@@ -20,6 +20,14 @@ We will aim to provide:
 
 ## Migration Log
 
+### v0.6.0
+
+`list_collections` now returns a list of collection *names*, instead of collection objects. 
+
+Previously, `list_collections` returned a list of collection objects, configured with the default embedding function. If one of your collections was created with a different embedding function, using the version returned by `list_collections` would result in various errors.
+
+We are working on embedding function persistence to allow you to configure a collection with an embedding function once, and not have to specify it again (in `get_collection` for example). 
+
 ### v0.5.17
 
 We no longer support sending empty lists or dictionaries for metadata filtering, ID filtering, etc. For example,

docs/docs.trychroma.com/pages/reference/py-client.md

@@ -257,10 +257,10 @@ class ClientAPI(BaseAPI, ABC)
 
 ```python
 def list_collections(limit: Optional[int] = None,
-                     offset: Optional[int] = None) -> Sequence[Collection]
+                     offset: Optional[int] = None) -> List[str]
 ```
 
-List all collections.
+List all collection names.
 
 **Arguments**: