From ae4920f1baa92e62cdb8aeee093fde97e478af07 Mon Sep 17 00:00:00 2001
From: Landan Seguin <landanjs@gmail.com>
Date: Thu, 20 Jun 2024 16:25:39 -0700
Subject: [PATCH] NoOp Model (#139)

---
 diffusion/models/__init__.py |  2 ++
 diffusion/models/noop.py     | 49 ++++++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 diffusion/models/noop.py

diff --git a/diffusion/models/__init__.py b/diffusion/models/__init__.py
index 67f61ac2..0928c83a 100644
--- a/diffusion/models/__init__.py
+++ b/diffusion/models/__init__.py
@@ -5,6 +5,7 @@
 
 from diffusion.models.models import (build_autoencoder, build_diffusers_autoencoder, continuous_pixel_diffusion,
                                      discrete_pixel_diffusion, stable_diffusion_2, stable_diffusion_xl)
+from diffusion.models.noop import NoOpModel
 from diffusion.models.pixel_diffusion import PixelDiffusion
 from diffusion.models.stable_diffusion import StableDiffusion
 
@@ -13,6 +14,7 @@
     'build_diffusers_autoencoder',
     'continuous_pixel_diffusion',
     'discrete_pixel_diffusion',
+    'NoOpModel',
     'PixelDiffusion',
     'stable_diffusion_2',
     'stable_diffusion_xl',
diff --git a/diffusion/models/noop.py b/diffusion/models/noop.py
new file mode 100644
index 00000000..246be970
--- /dev/null
+++ b/diffusion/models/noop.py
@@ -0,0 +1,49 @@
+# Copyright 2022 MosaicML Diffusion authors
+# SPDX-License-Identifier: Apache-2.0
+
+"""NoOpModel algorithm and class."""
+
+from typing import Any, Dict, Optional, Tuple, Union
+
+import torch
+import torch.nn.functional as F
+from composer.models.base import ComposerModel
+from torchmetrics import Metric
+
+from diffusion.models.text_encoder import MultiTokenizer
+
+
+class NoOpModel(ComposerModel):
+    """No-op model used to measure dataloader throughput.
+
+    Args:
+        tokenizer_names (str, Tuple[str, ...]): HuggingFace name(s) of the tokenizer(s) to load.
+            Default: ``('stabilityai/stable-diffusion-xl-base-1.0/tokenizer',
+            'stabilityai/stable-diffusion-xl-base-1.0/tokenizer_2')``.
+    """
+
+    def __init__(
+        self,
+        tokenizer_names: Union[str, Tuple[str, ...]] = ('stabilityai/stable-diffusion-xl-base-1.0/tokenizer',
+                                                        'stabilityai/stable-diffusion-xl-base-1.0/tokenizer_2'),
+    ):
+        super().__init__()
+        self.weight = torch.nn.Linear(in_features=1, out_features=16)
+        self.tokenizer = MultiTokenizer(tokenizer_names_or_paths=tokenizer_names)
+
+    def loss(self, outputs: torch.Tensor, batch):
+        y = torch.randn_like(self.weight.weight)
+        return F.mse_loss(outputs, y)
+
+    def forward(self, batch):
+        input = torch.randn_like(self.weight.weight).sum().unsqueeze(0)
+        return self.weight(input)
+
+    def get_metrics(self, is_train: bool) -> Dict[str, Metric]:
+        return {}
+
+    def eval_forward(self, batch, outputs: Optional[Any] = None):
+        return self.forward(batch)
+
+    def update_metric(self, batch: Any, outputs: Any, metric: Metric) -> None:
+        pass