first draft

src/banks/env.py

@@ -4,7 +4,7 @@
 from jinja2 import Environment, PackageLoader, select_autoescape
 
 from .config import config
-from .filters import cache_control, lemmatize, tool
+from .filters import cache_control, image, lemmatize, tool
 
 
 def _add_extensions(_env):
@@ -38,7 +38,9 @@ def _add_extensions(_env):
 
 
 # Setup custom filters and defaults
-env.filters["lemmatize"] = lemmatize
 env.filters["cache_control"] = cache_control
+env.filters["image"] = image
+env.filters["lemmatize"] = lemmatize
 env.filters["tool"] = tool
+
 _add_extensions(env)

src/banks/extensions/chat.py

@@ -33,12 +33,12 @@ def content(self) -> ChatMessageContent:
 
         return self._content_blocks
 
-    def handle_starttag(self, tag, _):
-        if tag == "content_block_txt":
+    def handle_starttag(self, tag, attrs):  # noqa
+        if tag == "content_block":
             self._parse_block_content = True
 
     def handle_endtag(self, tag):
-        if tag == "content_block_txt":
+        if tag == "content_block":
             self._parse_block_content = False
 
     def handle_data(self, data):

src/banks/filters/__init__.py

@@ -2,11 +2,13 @@
 #
 # SPDX-License-Identifier: MIT
 from .cache_control import cache_control
+from .image import image
 from .lemmatize import lemmatize
 from .tool import tool
 
 __all__ = (
     "cache_control",
+    "image",
     "lemmatize",
     "tool",
 )

src/banks/filters/cache_control.py

@@ -17,8 +17,8 @@ def cache_control(value: str, cache_type: str = "ephemeral") -> str:
         ```
 
     Important:
-        this filter marks the content to cache by surrounding it with `<content_block_txt>` and
-        `</content_block_txt>`, so it's only useful when used within a `{% chat %}` block.
+        this filter marks the content to cache by surrounding it with `<content_block>` and
+        `</content_block>`, so it's only useful when used within a `{% chat %}` block.
     """
     block = ContentBlock.model_validate({"type": "text", "text": value, "cache_control": {"type": cache_type}})
-    return f"<content_block_txt>{block.model_dump_json()}</content_block_txt>"
+    return f"<content_block>{block.model_dump_json()}</content_block>"

src/banks/filters/image.py

@@ -0,0 +1,40 @@
+# SPDX-FileCopyrightText: 2023-present Massimiliano Pippi <[email protected]>
+#
+# SPDX-License-Identifier: MIT
+from pathlib import Path
+from urllib.parse import urlparse
+
+from banks.types import ContentBlock, ImageUrl
+
+
+def _is_url(string: str) -> bool:
+    try:
+        result = urlparse(string)
+        return all([result.scheme, result.netloc])
+    except ValueError:
+        return False
+
+
+def image(value: str) -> str:
+    """Wrap the filtered value into a ContentBlock with the proper cache_control field set.
+
+    The resulting ChatMessage will have the field `content` populated with a list of ContentBlock objects.
+
+    Example:
+        ```jinja
+        Describe what you see
+
+        {{ "path/to/image/file" | image }}
+        ```
+
+    Important:
+        this filter marks the content to cache by surrounding it with `<content_block>` and
+        `</content_block>`, so it's only useful when used within a `{% chat %}` block.
+    """
+    if _is_url(value):
+        image_url = ImageUrl(url=value)
+    else:
+        image_url = ImageUrl.from_path(Path(value))
+
+    block = ContentBlock.model_validate({"type": "image_url", "image_url": image_url})
+    return f"<content_block>{block.model_dump_json()}</content_block>"

src/banks/types.py

@@ -1,8 +1,10 @@
 # SPDX-FileCopyrightText: 2023-present Massimiliano Pippi <[email protected]>
 #
 # SPDX-License-Identifier: MIT
+import base64
 from enum import Enum
 from inspect import Parameter, getdoc, signature
+from pathlib import Path
 from typing import Callable
 
 from pydantic import BaseModel
@@ -26,9 +28,14 @@ class ImageUrl(BaseModel):
     url: str
 
     @classmethod
-    def from_base64(cls, media_type: str, base64_str: str):
+    def from_base64(cls, media_type: str, base64_str: str) -> Self:
         return cls(url=f"data:{media_type};base64,{base64_str}")
 
+    @classmethod
+    def from_path(cls, file_path: Path) -> Self:
+        with open(file_path, "rb") as image_file:
+            return cls.from_base64("image/jpeg", base64.b64encode(image_file.read()).decode("utf-8"))
+
 
 class ContentBlock(BaseModel):
     type: ContentBlockType

tests/test_cache_control.py

@@ -3,6 +3,6 @@
 
 def test_cache_control():
     res = cache_control("foo", "ephemeral")
-    res = res.replace("<content_block_txt>", "")
-    res = res.replace("</content_block_txt>", "")
+    res = res.replace("<content_block>", "")
+    res = res.replace("</content_block>", "")
     assert res == '{"type":"text","cache_control":{"type":"ephemeral"},"text":"foo","image_url":null}'

tests/test_chat.py

@@ -30,7 +30,7 @@ def test_content_block_parser_init():
 def test_content_block_parser_single_with_cache_control():
     p = _ContentBlockParser()
     p.feed(
-        '<content_block_txt>{"type":"text","cache_control":{"type":"ephemeral"},"text":"foo","source":null}</content_block_txt>'
+        '<content_block>{"type":"text","cache_control":{"type":"ephemeral"},"text":"foo","source":null}</content_block>'
     )
     assert p.content == [
         ContentBlock(type=ContentBlockType.text, cache_control=CacheControl(type="ephemeral"), text="foo", source=None)
@@ -39,15 +39,15 @@ def test_content_block_parser_single_with_cache_control():
 
 def test_content_block_parser_single_no_cache_control():
     p = _ContentBlockParser()
-    p.feed('<content_block_txt>{"type":"text","cache_control":null,"text":"foo","source":null}</content_block_txt>')
+    p.feed('<content_block>{"type":"text","cache_control":null,"text":"foo","source":null}</content_block>')
     assert p.content == "foo"
 
 
 def test_content_block_parser_multiple():
     p = _ContentBlockParser()
     p.feed(
-        '<content_block_txt>{"type":"text","cache_control":null,"text":"foo","source":null}</content_block_txt>'
-        '<content_block_txt>{"type":"text","cache_control":null,"text":"bar","source":null}</content_block_txt>'
+        '<content_block>{"type":"text","cache_control":null,"text":"foo","source":null}</content_block>'
+        '<content_block>{"type":"text","cache_control":null,"text":"bar","source":null}</content_block>'
     )
     assert p.content == [
         ContentBlock(type=ContentBlockType.text, cache_control=None, text="foo", source=None),