Add A1111 example with tunnels (bad) (#473)

* Add A1111 example with tunnels (bad)

* Ruff

* Simplify example and remove the launcher UI

06_gpu_and_ml/stable_diffusion/a1111_webui.py

@@ -0,0 +1,100 @@
+# ---
+# lambda-test: false
+# ---
+# # Stable Diffusion (A1111)
+#
+# This example runs the popular [AUTOMATIC1111/stable-diffusion-webui](https://github.com/AUTOMATIC1111/stable-diffusion-webui)
+# project on Modal, without modification. We start a Modal container with an A10G GPU, run the server as a
+# subprocess, and forward the port using a [tunnel](/docs/guide/tunnels).
+
+import socket
+import subprocess
+import time
+import webbrowser
+
+from modal import Image, Queue, Stub, forward
+
+stub = Stub("example-a1111-webui")
+stub.urls = Queue.new()  # TODO: FunctionCall.get() doesn't support generators.
+
+
+def wait_for_port(port: int):
+    while True:
+        try:
+            with socket.create_connection(("127.0.0.1", port), timeout=5.0):
+                break
+        except OSError:
+            time.sleep(0.1)
+
+
+# The following function starts the web UI container. Notice that it requires a few steps to
+# install dependencies, since `stable-diffusion-webui` doesn't come with a prepackaged script
+# to do this. (It usually installs dependencies on first launch.)
+#
+# After defining the custom container image, we start the server with `accelerate launch`. This
+# function is also where you would configure hardware resources, CPU/memory, and timeouts.
+#
+# If you want to run it with an A100 GPU, just change `gpu="a10g"` to `gpu="a100"`.
+
+
+@stub.function(
+    image=Image.debian_slim()
+    .apt_install(
+        "wget",
+        "git",
+        "libgl1",
+        "libglib2.0-0",
+        "google-perftools",  # For tcmalloc
+    )
+    .env({"LD_PRELOAD": "/usr/lib/x86_64-linux-gnu/libtcmalloc.so.4"})
+    .run_commands(
+        "git clone --depth 1 --branch v1.6.0 https://github.com/AUTOMATIC1111/stable-diffusion-webui /webui",
+        "python -m venv /webui/venv",
+        "cd /webui && . venv/bin/activate && "
+        + "python -c 'from modules import launch_utils; launch_utils.prepare_environment()' --xformers",
+        gpu="a10g",
+    )
+    .run_commands(
+        "cd /webui && . venv/bin/activate && "
+        + "python -c 'from modules import shared_init, initialize; shared_init.initialize(); initialize.initialize()'",
+    ),
+    gpu="a10g",
+    cpu=2,
+    memory=1024,
+    timeout=3600,
+)
+def start_web_ui():
+    START_COMMAND = r"""
+cd /webui && \
+. venv/bin/activate && \
+accelerate launch \
+    --num_processes=1 \
+    --num_machines=1 \
+    --mixed_precision=fp16 \
+    --dynamo_backend=inductor \
+    --num_cpu_threads_per_process=6 \
+    /webui/launch.py \
+        --skip-prepare-environment \
+        --listen \
+        --port 8000
+"""
+    with forward(8000) as tunnel:
+        p = subprocess.Popen(START_COMMAND, shell=True)
+        wait_for_port(8000)
+        print("[MODAL] ==> Accepting connections at", tunnel.url)
+        stub.urls.put(tunnel.url)
+        p.wait(3600)
+
+
+# The first run may take a few minutes to build the image. When the container starts, it will open
+# the page in your browser.
+
+
+@stub.local_entrypoint()
+def main(no_browser: bool = False):
+    start_web_ui.spawn()
+    url = stub.urls.get()
+    if not no_browser:
+        webbrowser.open(url)
+    while True:  # TODO: FunctionCall.get() doesn't support generators.
+        time.sleep(1)