feat(chromadb)!: Multi-modal and tenants support (#210)

New features:
- tenants and databases support
- global headers (e.g. for authentication)
- multi-modal support

packages/chromadb/build.yaml

@@ -7,3 +7,6 @@ targets:
             - prefer_final_parameters
             - require_trailing_commas
             - non_constant_identifier_names
+      json_serializable:
+        options:
+          explicit_to_json: true

packages/chromadb/lib/chromadb.dart

@@ -3,6 +3,8 @@ library;
 
 export 'src/chroma_client.dart';
 export 'src/collection.dart';
+export 'src/embeddings/embedding_function.dart';
 export 'src/generated/client.dart' show ChromaApiClientException;
 export 'src/generated/schema/schema.dart'
-    show CollectionType, GetEmbedding, GetResponse, QueryResponse;
+    show CollectionType, GetResponse, QueryResponse;
+export 'src/loaders/data_loader.dart';

packages/chromadb/lib/src/chroma_client.dart

@@ -4,49 +4,67 @@ import 'collection.dart';
 import 'embeddings/embedding_function.dart';
 import 'generated/client.dart';
 import 'generated/schema/schema.dart';
+import 'loaders/data_loader.dart';
 
 /// {@template chroma_client}
 /// Chroma open-source embedding database API client.
 /// {@endtemplate}
 class ChromaClient {
   /// {@macro chroma_client}
   ChromaClient({
-    final String host = 'http://localhost:8000',
+    this.tenant = 'default_tenant',
+    this.database = 'default_database',
+    final String baseUrl = 'http://localhost:8000',
+    final Map<String, String>? headers,
     final http.Client? client,
-  }) : _api = ChromaApiClient(host: host, client: client);
+  }) : _api = ChromaApiClient(
+          baseUrl: baseUrl,
+          headers: headers ?? const {},
+          client: client,
+        );
 
   /// The API client.
   final ChromaApiClient _api;
 
-  /// Resets the state of the object by making an API call to the reset
-  /// endpoint.
-  Future<bool> reset() {
-    return _api.reset();
-  }
+  /// The tenant name.
+  final String tenant;
 
-  /// Returns the version of the Chroma API.
-  Future<String> version() {
-    return _api.version();
-  }
+  /// The database name.
+  final String database;
 
-  /// Returns a heartbeat from the Chroma API.
+  /// Get the current time in nanoseconds since epoch.
+  /// Used to check if the server is alive.
+  /// Returns the current time in nanoseconds since epoch.
   Future<int> heartbeat() async {
     final res = await _api.heartbeat();
     return res['nanosecond heartbeat'] ?? 0;
   }
 
+  /// Lists all collections.
+  Future<List<CollectionType>> listCollections() {
+    return _api.listCollections(
+      tenant: tenant,
+      database: database,
+    );
+  }
+
   /// Creates a new collection with the specified properties.
   ///
   /// - [name] - The name of the collection.
   /// - [metadata] - Optional metadata associated with the collection.
   /// - [embeddingFunction] - Optional custom embedding function for the
   ///   collection.
+  /// - [dataLoader] - Optional data loader for the collection. It is used to
+  ///   load the data from a stored URI when needed.
   Future<Collection> createCollection({
     required final String name,
     final Map<String, dynamic>? metadata,
     final EmbeddingFunction? embeddingFunction,
+    final DataLoader<Loadable>? dataLoader,
   }) async {
     final res = await _api.createCollection(
+      tenant: tenant,
+      database: database,
       request: CreateCollection(
         name: name,
         metadata: metadata,
@@ -56,7 +74,10 @@ class ChromaClient {
       name: res.name,
       id: res.id,
       metadata: res.metadata,
+      tenant: tenant,
+      database: database,
       embeddingFunction: embeddingFunction,
+      dataLoader: dataLoader,
       api: _api,
     );
   }
@@ -66,12 +87,18 @@ class ChromaClient {
   /// - [name] - The name of the collection.
   /// - [metadata] - Optional metadata associated with the collection.
   /// - [embeddingFunction] - Optional custom embedding function for the
+  ///   collection.
+  /// - [dataLoader] - Optional data loader for the collection. It is used to
+  ///   load the data from a stored URI when needed.
   Future<Collection> getOrCreateCollection({
     required final String name,
     final Map<String, dynamic>? metadata,
     final EmbeddingFunction? embeddingFunction,
+    final DataLoader<Loadable>? dataLoader,
   }) async {
     final res = await _api.createCollection(
+      tenant: tenant,
+      database: database,
       request: CreateCollection(
         name: name,
         metadata: metadata,
@@ -82,33 +109,39 @@ class ChromaClient {
       name: res.name,
       id: res.id,
       metadata: res.metadata,
+      tenant: tenant,
+      database: database,
       embeddingFunction: embeddingFunction,
+      dataLoader: dataLoader,
       api: _api,
     );
   }
 
-  /// Lists all collections.
-  Future<List<CollectionType>> listCollections() {
-    return _api.listCollections();
-  }
-
   /// Gets a collection with the specified name.
   ///
   /// - [name] - The name of the collection.
   /// - [embeddingFunction] - Optional custom embedding function for the
   ///   collection.
+  /// - [dataLoader] - Optional data loader for the collection. It is used to
+  ///   load the data from a stored URI when needed.
   Future<Collection> getCollection({
     required final String name,
     final EmbeddingFunction? embeddingFunction,
+    final DataLoader<Loadable>? dataLoader,
   }) async {
     final res = await _api.getCollection(
       collectionName: name,
+      tenant: tenant,
+      database: database,
     );
     return Collection(
       name: res.name,
       id: res.id,
       metadata: res.metadata,
+      tenant: tenant,
+      database: database,
       embeddingFunction: embeddingFunction,
+      dataLoader: dataLoader,
       api: _api,
     );
   }
@@ -121,6 +154,20 @@ class ChromaClient {
   }) async {
     await _api.deleteCollection(
       collectionName: name,
+      tenant: tenant,
+      database: database,
     );
   }
+
+  /// Resets the database. This will delete all collections and entries.
+  /// Returns true if the database was reset successfully.
+  Future<bool> reset() {
+    return _api.reset();
+  }
+
+  /// Returns the version of the Chroma API.
+  Future<String> version() async {
+    final version = await _api.version();
+    return version.replaceAll('"', '');
+  }
 }