feat: OllamaVlmModel for Granite Vision 3.2 (#1337)

* build: Add ollama sdk dependency

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* feat: Add option plumbing for OllamaVlmOptions in pipeline_options

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* feat: Full implementation of OllamaVlmModel

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* feat: Connect "granite_vision_ollama" pipeline option to CLI

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* Revert "build: Add ollama sdk dependency"

After consideration, we're going to use the generic OpenAI API instead
of the Ollama-specific API to avoid duplicate work.

This reverts commit bc6b366468cdd66b52540aac9c7d8b584ab48ad0.

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* refactor: Move OpenAI API call logic into utils.utils

This will allow reuse of this logic in a generic VLM model

NOTE: There is a subtle change here in the ordering of the text prompt and
the image in the call to the OpenAI API. When run against Ollama, this
ordering makes a big difference. If the prompt comes before the image, the
result is terse and not usable whereas the prompt coming after the image
works as expected and matches the non-OpenAI chat API.

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* refactor: Refactor from Ollama SDK to generic OpenAI API

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* fix: Linting, formatting, and bug fixes

The one bug fix was in the timeout arg to openai_image_request. Otherwise,
this is all style changes to get MyPy and black passing cleanly.

Branch: OllamaVlmModel

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>

* remove model from download enum

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

* generalize input args for other API providers

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

* rename and refactor

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

* add example

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

* require flag for remote services

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

* disable example from CI

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

* add examples to docs

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

---------

Signed-off-by: Gabe Goodhart <ghart@us.ibm.com>
Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>
Co-authored-by: Michele Dolfi <dol@zurich.ibm.com>

docling/datamodel/base_models.py

@@ -262,3 +262,35 @@ class Page(BaseModel):
     @property
     def image(self) -> Optional[Image]:
         return self.get_image(scale=self._default_image_scale)
+
+
+## OpenAI API Request / Response Models ##
+
+
+class OpenAiChatMessage(BaseModel):
+    role: str
+    content: str
+
+
+class OpenAiResponseChoice(BaseModel):
+    index: int
+    message: OpenAiChatMessage
+    finish_reason: str
+
+
+class OpenAiResponseUsage(BaseModel):
+    prompt_tokens: int
+    completion_tokens: int
+    total_tokens: int
+
+
+class OpenAiApiResponse(BaseModel):
+    model_config = ConfigDict(
+        protected_namespaces=(),
+    )
+
+    id: str
+    model: Optional[str] = None  # returned by openai
+    choices: List[OpenAiResponseChoice]
+    created: int
+    usage: OpenAiResponseUsage