feat: Add DevChat workflow extension API docs

- Implemented inline documentation for foundation module functions
- Included docstrings with detailed descriptions and return types
- Functions documented include context retrieval and user input handling

Author: yangbobo2021

libs/foundation/__init__.py

@@ -0,0 +1,17 @@
+from .foundation import (
+	get_context_contents,
+	get_devchat_site_packages_path,
+	get_llm_model,
+	get_parent_hash,
+	get_user_input_files,
+	get_user_input_text
+)
+
+__all__ = [
+	"get_context_contents",
+	"get_devchat_site_packages_path",
+	"get_llm_model",
+	"get_parent_hash",
+	"get_user_input_files",
+	"get_user_input_text"
+]

libs/foundation/foundation.py

@@ -0,0 +1,107 @@
+import os
+import json
+
+
+def get_devchat_site_packages_path():
+    """@DevChatApi
+    Retrieve the DevChat site packages path from the environment variable.
+
+    Returns:
+        str: The path stored in DEVCHAT_PYTHONPATH environment variable, 
+             or an empty string if the variable isn't set.
+    """
+    return os.environ.get("DEVCHAT_PYTHONPATH", "")
+
+
+def get_llm_model():
+    """@DevChatApi
+    Retrieve the DevChat LLM model from the environment variable.
+
+    Returns:
+        str: The LLM model stored in LLM_MODEL environment variable, 
+             or an empty string if the variable isn't set.
+    """
+    return os.environ.get("LLM_MODEL", "gpt-3.5-turbo-1106")
+
+
+def get_parent_hash():
+    """@DevChatApi
+    Retrieves the parent hash value from the environment variable.
+
+    This function is designed to obtain the hash value of the parent message in a sequence of chat interactions,
+    where each pair of question and response is associated with respective hash values. It helps in reconstructing
+    the order of conversation threads by providing the parent hash for the current message.
+
+    Returns:
+        str: The parent hash value stored in the PARENT_HASH environment variable,
+             or an empty string if the variable isn't set.
+    """
+    return os.environ.get("PARENT_HASH", "")
+
+
+def get_context_contents():
+    """@DevChatApi
+    Retrieve the chat context history from an environment variable.
+
+    This function looks up the `CONTEXT_CONTENTS` environment variable, parses it as JSON, and returns the result.
+    It's used to obtain the historical content of the chat, which is stored in a JSON array format.
+    Each item in the array represents a message with a sender role and content, for example:
+    [{"role": "user", "content": "User's message"}, {"role": "assistant", "content": "Assistant's reply"}].
+
+    Returns:
+        list: A list of dictionaries representing the chat history. Each dictionary contains the keys 'role' and
+              'content', corresponding to who sent the message and what the message was, respectively.
+              If the `CONTEXT_CONTENTS` variable is not set, an empty list is returned.
+    """
+    return json.loads(os.environ.get("CONTEXT_CONTENTS", "[]"))
+
+
+def get_user_input_text():
+    """@DevChatApi
+    Fetch the most recent user input from the chat context.
+
+    This function retrieves the current chat context by calling the
+    `get_context_contents` function, which returns a list of message
+    dictionaries. It then extracts the content of the last message in the
+    context, assuming it's from the user, returning it as a string. If the
+    context is empty, an empty string is returned. This function is typically
+    used to get the last input provided by the user in the chat interface.
+    
+    Returns:
+        str: The content of the most recent user input message if it exists,
+             otherwise an empty string.
+    """
+    contexts = get_context_contents()
+    user_index = 0
+    for index, context in enumerate(contexts):
+        if context["role"] == "user":
+            user_index = index
+    return contexts[user_index]["content"] if len(contexts) > 0 else ""
+
+
+# 获取用户输入的相关文件内容。这些相关文件一般通过Add to DevChat右键菜单添加到聊天上下文中。
+def get_user_input_files():
+    """@DevChatApi
+    Retrieve a list of file contents that were input by the user.
+
+    This function scans through the chat context (which contains all messages and interactions
+    within a chat session) to identify any files that were added by the user, typically via the
+    'Add to DevChat' right-click context menu option. Files added by the user are delineated in the
+    chat context as having a 'role' other than 'assistant'. This function finds the last occurrence
+    of a message where the 'assistant' role is responsible and then returns the content of all
+    subsequent messages until the penultimate one, assuming these are the user's input files.
+
+    Returns:
+        list[str]: A list of the content from all files that were input by the user. Each item
+                   in the list is the contents of one file.
+    """
+    contexts = get_context_contents()
+    last_index = 0
+    for index, item in enumerate(contexts):
+        if item["role"] == "user":
+            last_index = index + 1
+    if last_index == len(contexts):
+        return []
+    return [item["content"] for item in contexts[last_index:]]
+
+