feat(adapters): support extra fields in OpenAI adapter

Author: Davidyz

doc/configuration/adapters.md

@@ -380,3 +380,40 @@ require("codecompanion").setup({
 }),
 ```
 
+## Setup: OpenRouter with Reasoning Output
+
+```lua 
+require("codecompanion").setup({
+  adapters = {
+    http = {
+      openrouter = function()
+        return require("codecompanion.adapters").extend("openai_compatible", {
+          env = {
+            url = "https://openrouter.ai/api",
+            api_key = "OPENROUTER_API_KEY",
+            chat_url = "/v1/chat/completions",
+          },
+          handlers = {
+            parse_extra = function(self, data)
+              local extra = data.extra
+              if extra and extra.reasoning then
+                data.output.reasoning = { content = extra.reasoning }
+                data.output.content = nil
+              end
+              return data
+            end,
+          },
+        })
+      end,
+    },
+  },
+  strategies = {
+    chat = {
+      adapter = "openrouter",
+    },
+    inline = {
+      adapter = "openrouter",
+    },
+  },
+})
+```

lua/codecompanion/adapters/http/init.lua

@@ -50,6 +50,7 @@ local function get_handler(adapter, name)
     parse_chat = "chat_output",
     parse_inline = "inline_output",
     parse_tokens = "tokens",
+    parse_extra = "parse_extra",
 
     -- tools
     format_calls = "format_tool_calls",

lua/codecompanion/adapters/http/openai.lua

@@ -1,5 +1,34 @@
 local adapter_utils = require("codecompanion.utils.adapters")
 local log = require("codecompanion.utils.log")
+local CONSTANTS = {
+  STANDARD_MESSAGE_FIELDS = {
+    -- fields that are defined in the standard openai chat-completion API (inc. streaming and non-streaming)
+    "content",
+    "function_call",
+    "refusal",
+    "role",
+    "tool_calls",
+    "annotations",
+    "audio",
+  },
+}
+
+---@param obj table?
+---@return table?
+local function find_extra_fields(obj)
+  if obj == nil then
+    return nil
+  end
+  local extra = {}
+  vim.iter(obj):each(function(k, v)
+    if not vim.list_contains(CONSTANTS.STANDARD_MESSAGE_FIELDS, k) then
+      extra[k] = v
+    end
+  end)
+  if not vim.tbl_isempty(extra) then
+    return extra
+  end
+end
 
 ---@class CodeCompanion.HTTPAdapter.OpenAI: CodeCompanion.HTTPAdapter
 return {
@@ -257,6 +286,7 @@ return {
           role = delta.role,
           content = delta.content,
         },
+        extra = find_extra_fields(delta),
       }
     end,
 

lua/codecompanion/strategies/chat/init.lua

@@ -1009,6 +1009,12 @@ function Chat:_submit_http(payload)
     end
 
     local result = adapters.call_handler(adapter, "parse_chat", data, tools)
+
+    local parse_extra = adapters.get_handler(adapter, "parse_extra")
+    if result and result.extra and type(parse_extra) == "function" then
+      result = parse_extra(adapter, result)
+    end
+
     if result and result.status then
       self.status = result.status
       if self.status == CONSTANTS.STATUS_SUCCESS then