feat(diffusers): overcome prompt limit (#904)

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

extra/grpc/diffusers/backend_diffusers.py

@@ -14,8 +14,10 @@ import torch
 from torch import autocast
 from diffusers import StableDiffusionXLPipeline, DPMSolverMultistepScheduler, StableDiffusionPipeline, DiffusionPipeline, EulerAncestralDiscreteScheduler
 from diffusers.pipelines.stable_diffusion import safety_checker
+from compel import Compel
 
 _ONE_DAY_IN_SECONDS = 60 * 60 * 24
+COMPEL=os.environ.get("COMPEL", "1") == "1"
 
 # https://github.com/CompVis/stable-diffusion/issues/239#issuecomment-1627615287
 def sc(self, clip_input, images) : return images, [False for i in images]
@@ -99,6 +101,8 @@ class BackendServicer(backend_pb2_grpc.BackendServicer):
                 self.pipe.scheduler = DPMSolverMultistepScheduler.from_config(self.pipe.scheduler.config, algorithm_type="sde-dpmsolver++")
             if request.CUDA:
                 self.pipe.to('cuda')
+
+            self.compel = Compel(tokenizer=self.pipe.tokenizer, text_encoder=self.pipe.text_encoder)
         except Exception as err:
             return backend_pb2.Result(success=False, message=f"Unexpected {err=}, {type(err)=}")
         # Implement your logic here for the LoadModel service
@@ -127,7 +131,15 @@ class BackendServicer(backend_pb2_grpc.BackendServicer):
 
         # create a dictionary of parameters by using the keys from EnableParameters and the values from defaults
         kwargs = {key: options[key] for key in keys}
-
+        image = {}
+        if COMPEL:
+            conditioning = self.compel.build_conditioning_tensor(prompt)
+            kwargs["prompt_embeds"]= conditioning
+            # pass the kwargs dictionary to the self.pipe method
+            image = self.pipe( 
+                **kwargs
+                ).images[0] 
+        else:
             # pass the kwargs dictionary to the self.pipe method
             image = self.pipe(
                 prompt, 

extra/requirements.txt

@@ -4,3 +4,4 @@ google
 protobuf
 six
 omegaconf
+compel