enable lazy caching for chatinterface (#10015)

* lazy chat

* add changeset

* lazy caching

* lazy caching

* revert

* fix this

* changes

* changes

* format

* changes

* add env variable

* revert

* add changeset

* lazy

* fix

* chat interface

* fix test

---------

Co-authored-by: gradio-pr-bot <[email protected]>

.changeset/many-horses-judge.md

@@ -0,0 +1,5 @@
+---
+"gradio": patch
+---
+
+fix:enable lazy caching for chatinterface

.config/playwright-setup.js

@@ -84,7 +84,8 @@ function spawn_gradio_app(app, port, verbose) {
 				...process.env,
 				PYTHONUNBUFFERED: "true",
 				GRADIO_ANALYTICS_ENABLED: "False",
-				GRADIO_IS_E2E_TEST: "1"
+				GRADIO_IS_E2E_TEST: "1",
+				GRADIO_RESET_EXAMPLES_CACHE: "True"
 			}
 		});
 		_process.stdout.setEncoding("utf8");

demo/test_chatinterface_examples/lazy_caching_examples_testcase.py

@@ -0,0 +1,27 @@
+import gradio as gr
+
+def generate(
+    message: str,
+    chat_history: list[dict],
+):
+
+    output = ""
+    for character in message:
+        output += character
+        yield output
+
+
+demo = gr.ChatInterface(
+    fn=generate,
+    examples=[
+        ["Hey"],
+        ["Can you explain briefly to me what is the Python programming language?"],
+    ],
+    cache_examples=True,
+    cache_mode="lazy",
+    type="messages",
+)
+
+
+if __name__ == "__main__":
+    demo.launch()

demo/test_chatinterface_examples/run.ipynb

@@ -1 +1 @@
-{"cells": [{"cell_type": "markdown", "id": "302934307671667531413257853548643485645", "metadata": {}, "source": ["# Gradio Demo: test_chatinterface_examples"]}, {"cell_type": "code", "execution_count": null, "id": "272996653310673477252411125948039410165", "metadata": {}, "outputs": [], "source": ["!pip install -q gradio "]}, {"cell_type": "code", "execution_count": null, "id": "288918539441861185822528903084949547379", "metadata": {}, "outputs": [], "source": ["# Downloading files from the demo repo\n", "import os\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/eager_caching_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/multimodal_messages_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/multimodal_tuples_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/tuples_examples_testcase.py"]}, {"cell_type": "code", "execution_count": null, "id": "44380577570523278879349135829904343037", "metadata": {}, "outputs": [], "source": ["import gradio as gr\n", "\n", "def generate(\n", "    message: str,\n", "    chat_history: list[dict],\n", "):\n", "\n", "    output = \"\"\n", "    for character in message:\n", "        output += character\n", "        yield output\n", "\n", "\n", "demo = gr.ChatInterface(\n", "    fn=generate,\n", "    examples=[\n", "        [\"Hey\"],\n", "        [\"Can you explain briefly to me what is the Python programming language?\"],\n", "    ],\n", "    cache_examples=False,\n", "    type=\"messages\",\n", ")\n", "\n", "\n", "if __name__ == \"__main__\":\n", "    demo.launch()\n"]}], "metadata": {}, "nbformat": 4, "nbformat_minor": 5}
+{"cells": [{"cell_type": "markdown", "id": "302934307671667531413257853548643485645", "metadata": {}, "source": ["# Gradio Demo: test_chatinterface_examples"]}, {"cell_type": "code", "execution_count": null, "id": "272996653310673477252411125948039410165", "metadata": {}, "outputs": [], "source": ["!pip install -q gradio "]}, {"cell_type": "code", "execution_count": null, "id": "288918539441861185822528903084949547379", "metadata": {}, "outputs": [], "source": ["# Downloading files from the demo repo\n", "import os\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/eager_caching_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/lazy_caching_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/multimodal_messages_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/multimodal_tuples_examples_testcase.py\n", "!wget -q https://github.com/gradio-app/gradio/raw/main/demo/test_chatinterface_examples/tuples_examples_testcase.py"]}, {"cell_type": "code", "execution_count": null, "id": "44380577570523278879349135829904343037", "metadata": {}, "outputs": [], "source": ["import gradio as gr\n", "\n", "def generate(\n", "    message: str,\n", "    chat_history: list[dict],\n", "):\n", "\n", "    output = \"\"\n", "    for character in message:\n", "        output += character\n", "        yield output\n", "\n", "\n", "demo = gr.ChatInterface(\n", "    fn=generate,\n", "    examples=[\n", "        [\"Hey\"],\n", "        [\"Can you explain briefly to me what is the Python programming language?\"],\n", "    ],\n", "    cache_examples=False,\n", "    type=\"messages\",\n", ")\n", "\n", "\n", "if __name__ == \"__main__\":\n", "    demo.launch()\n"]}], "metadata": {}, "nbformat": 4, "nbformat_minor": 5}

gradio/chat_interface.py

@@ -8,7 +8,7 @@
 import functools
 import inspect
 import warnings
-from collections.abc import AsyncGenerator, Callable, Sequence
+from collections.abc import AsyncGenerator, Callable, Generator, Sequence
 from pathlib import Path
 from typing import Literal, Union, cast
 
@@ -111,7 +111,7 @@ def __init__(
             example_labels: labels for the examples, to be displayed instead of the examples themselves. If provided, should be a list of strings with the same length as the examples list. Only applies when examples are displayed within the chatbot (i.e. when `additional_inputs` is not provided).
             example_icons: icons for the examples, to be displayed above the examples. If provided, should be a list of string URLs or local paths with the same length as the examples list. Only applies when examples are displayed within the chatbot (i.e. when `additional_inputs` is not provided).
             cache_examples: if True, caches examples in the server for fast runtime in examples. The default option in HuggingFace Spaces is True. The default option elsewhere is False.
-            cache_mode: if "eager", all examples are cached at app launch. The "lazy" option is not yet supported. If None, will use the GRADIO_CACHE_MODE environment variable if defined, or default to "eager".
+            cache_mode: if "eager", all examples are cached at app launch. If "lazy", examples are cached for all users after the first use by any user of the app. If None, will use the GRADIO_CACHE_MODE environment variable if defined, or default to "eager".
             title: a title for the interface; if provided, appears above chatbot in large font. Also used as the tab title when opened in a browser window.
             description: a description for the interface; if provided, appears above the chatbot and beneath the title in regular font. Accepts Markdown and HTML content.
             theme: a Theme object or a string representing a theme. If a string, will look for a built-in theme with that name (e.g. "soft" or "default"), or will attempt to load a theme from the Hugging Face Hub (e.g. "gradio/monochrome"). If None, will use the Default theme.
@@ -369,7 +369,7 @@ def _setup_events(self) -> None:
             and self.examples
             and not self._additional_inputs_in_examples
         ):
-            if self.cache_examples and self.cache_mode == "eager":
+            if self.cache_examples:
                 self.chatbot.example_select(
                     self.example_clicked,
                     None,
@@ -718,15 +718,15 @@ def option_clicked(
 
     def example_clicked(
         self, example: SelectData
-    ) -> tuple[TupleFormat | list[MessageDict], str | MultimodalPostprocess]:
+    ) -> Generator[
+        tuple[TupleFormat | list[MessageDict], str | MultimodalPostprocess], None, None
+    ]:
         """
-        When an example is clicked, the chat history is set to the complete example value
-        (including files). The saved input value is also set to complete example value
-        if multimodal is True, otherwise it is set to the text of the example.
+        When an example is clicked, the chat history (and saved input) is initially set only
+        to the example message. Then, if example caching is enabled, the cached response is loaded
+        and added to the chat history as well.
         """
-        if self.cache_examples and self.cache_mode == "eager":
-            history = self.examples_handler.load_from_cache(example.index)[0].root
-        elif self.type == "tuples":
+        if self.type == "tuples":
             history = [(example.value["text"], None)]
             for file in example.value.get("files", []):
                 history.append(((file["path"]), None))
@@ -735,7 +735,10 @@ def example_clicked(
             for file in example.value.get("files", []):
                 history.append(MessageDict(role="user", content=file))
         message = example.value if self.multimodal else example.value["text"]
-        return history, message
+        yield history, message
+        if self.cache_examples:
+            history = self.examples_handler.load_from_cache(example.index)[0].root
+            yield history, message
 
     def _process_example(
         self, message: ExampleMessage | str, response: MessageDict | str | None

gradio/helpers.py

@@ -9,6 +9,7 @@
 import csv
 import inspect
 import os
+import shutil
 import warnings
 from collections.abc import Callable, Iterable, Sequence
 from functools import partial
@@ -276,6 +277,11 @@ def __init__(
             simplify_file_data=False, verbose=False, dataset_file_name="log.csv"
         )
         self.cached_folder = utils.get_cache_folder() / str(self.dataset._id)
+        if (
+            os.environ.get("GRADIO_RESET_EXAMPLES_CACHE") == "True"
+            and self.cached_folder.exists()
+        ):
+            shutil.rmtree(self.cached_folder)
         self.cached_file = Path(self.cached_folder) / "log.csv"
         self.cached_indices_file = Path(self.cached_folder) / "indices.csv"
         self.run_on_click = run_on_click
@@ -495,13 +501,15 @@ def sync_lazy_cache(self, example_value: tuple[int, list[Any]], *input_values):
         with open(self.cached_indices_file, "a") as f:
             f.write(f"{example_index}\n")
 
-    async def cache(self) -> None:
+    async def cache(self, example_id: int | None = None) -> None:
         """
         Caches examples so that their predictions can be shown immediately.
+        Parameters:
+            example_id: The id of the example to process (zero-indexed). If None, all examples are cached.
         """
         if self.root_block is None:
             raise Error("Cannot cache examples if not in a Blocks context.")
-        if Path(self.cached_file).exists():
+        if Path(self.cached_file).exists() and example_id is None:
             print(
                 f"Using cache from '{utils.abspath(self.cached_folder)}' directory. If method or examples have changed since last caching, delete this folder to clear cache.\n"
             )
@@ -548,6 +556,8 @@ async def get_final_item(*args):
             if self.outputs is None:
                 raise ValueError("self.outputs is missing")
             for i, example in enumerate(self.examples):
+                if example_id is not None and i != example_id:
+                    continue
                 print(f"Caching example {i + 1}/{len(self.examples)}")
                 processed_input = self._get_processed_example(example)
                 if self.batch:
@@ -574,6 +584,16 @@ def load_from_cache(self, example_id: int) -> list[Any]:
         Parameters:
             example_id: The id of the example to process (zero-indexed).
         """
+        if self.cache_examples == "lazy":
+            if cached_index := self._get_cached_index_if_cached(example_id) is None:
+                client_utils.synchronize_async(self.cache, example_id)
+                with open(self.cached_indices_file, "a") as f:
+                    f.write(f"{example_id}\n")
+                with open(self.cached_indices_file) as f:
+                    example_id = len(f.readlines()) - 1
+            else:
+                example_id = cached_index
+
         with open(self.cached_file, encoding="utf-8") as cache:
             examples = list(csv.reader(cache))
         example = examples[example_id + 1]  # +1 to adjust for header

guides/04_additional-features/09_environment-variables.md

@@ -163,6 +163,16 @@ Environment variables in Gradio provide a way to customize your applications and
   export GRADIO_NODE_NUM_PORTS=200
   ```
 
+### 18. `GRADIO_RESET_EXAMPLES_CACHE`
+
+- **Description**: If set to "True", Gradio will delete and recreate the examples cache directory when the app starts instead of reusing the cached example if they already exist. 
+- **Default**: `"False"`
+- **Options**: `"True"`, `"False"`
+- **Example**:
+  ```sh
+  export GRADIO_RESET_EXAMPLES_CACHE="True"
+  ```
+
 ## How to Set Environment Variables
 
 To set environment variables in your terminal, use the `export` command followed by the variable name and its value. For example:

js/spa/test/test_chatinterface_examples.spec.ts

@@ -5,7 +5,8 @@ const cases = [
 	"tuples_examples",
 	"multimodal_tuples_examples",
 	"multimodal_messages_examples",
-	"eager_caching_examples"
+	"eager_caching_examples",
+	"lazy_caching_examples"
 ];
 
 for (const test_case of cases) {

test/test_chat_interface.py

@@ -95,7 +95,7 @@ def test_example_caching(self, connect):
             assert prediction_hi[0].root[0] == ("hi", "hi hi")
 
     @pytest.mark.asyncio
-    async def test_example_caching_lazy(self, connect):
+    async def test_example_caching_lazy(self):
         with patch(
             "gradio.utils.get_cache_folder", return_value=Path(tempfile.mkdtemp())
         ):
@@ -105,16 +105,10 @@ async def test_example_caching_lazy(self, connect):
                 cache_examples=True,
                 cache_mode="lazy",
             )
-            async for _ in chatbot.examples_handler.async_lazy_cache(
-                (0, ["hello"]), "hello"
-            ):
-                pass
-            with connect(chatbot):
-                prediction_hello = chatbot.examples_handler.load_from_cache(0)
+            prediction_hello = chatbot.examples_handler.load_from_cache(0)
             assert prediction_hello[0].root[0] == ("hello", "hello hello")
-            with pytest.raises(IndexError):
-                prediction_hi = chatbot.examples_handler.load_from_cache(1)
-                assert prediction_hi[0].root[0] == ("hi", "hi hi")
+            prediction_hi = chatbot.examples_handler.load_from_cache(1)
+            assert prediction_hi[0].root[0] == ("hi", "hi hi")
 
     def test_example_caching_async(self, connect):
         with patch(