feat(nodes): add dynamic prompt node

invokeai/app/invocations/prompt.py

@@ -1,9 +1,11 @@
-from typing import Literal
+import os
+from typing import Literal, Optional
 
 from pydantic.fields import Field
+from pyparsing import ParseException
 
-from .baseinvocation import BaseInvocationOutput
-
+from .baseinvocation import BaseInvocation, BaseInvocationOutput, InvocationContext
+from dynamicprompts import RandomPromptGenerator, CombinatorialPromptGenerator
 
 class PromptOutput(BaseInvocationOutput):
     """Base class for invocations that output a prompt"""
@@ -20,3 +22,45 @@ class PromptOutput(BaseInvocationOutput):
                 'prompt',
             ]
         }
+
+
+class PromptListOutput(BaseInvocationOutput):
+    """Base class for invocations that output a list of prompts"""
+
+    # fmt: off
+    type: Literal["prompt_list"] = "prompt_list"
+
+    prompts: list[str] = Field(description="The output prompts")
+    count: int = Field(description="The size of the prompts list")
+    # fmt: on
+
+    class Config:
+        schema_extra = {"required": ["type", "prompts", "count"]}
+
+
+class DynamicPromptInvocation(BaseInvocation):
+    """Parses a prompt using adieyal/dynamicprompts' random or combinatorial generator"""
+
+    type: Literal["dynamic_prompt"] = "dynamic_prompt"
+    prompt: str = Field(
+        default=None, description="The prompt to parse with dynamicprompts"
+    )
+    max_prompts: int = Field(default=1, description="The number of prompts to generate")
+    combinatorial: bool = Field(
+        default=False, description="Whether to use the combinatorial generator"
+    )
+
+    def invoke(self, context: InvocationContext) -> PromptListOutput:
+        try:
+            if self.combinatorial:
+                generator = CombinatorialPromptGenerator()
+                prompts = generator.generate(self.prompt, max_prompts=self.max_prompts)
+            else:
+                generator = RandomPromptGenerator()
+                prompts = generator.generate(self.prompt, num_images=self.max_prompts)
+        except ParseException as e:
+            warning = f"Invalid dynamic prompt: {e}"
+            context.services.logger.warn(warning)
+            return PromptListOutput(prompts=[self.prompt], count=1)
+
+        return PromptListOutput(prompts=prompts, count=len(prompts))