feat(ai-proxy): support automatic protocol translation from Claude to OpenAI

apisix/plugins/ai-drivers/openai-base.lua

@@ -16,6 +16,8 @@
 --
 local _M = {}
 
+local claude_converter = require("apisix.plugins.ai-proxy.converter.claude_to_openai")
+
 local mt = {
     __index = _M
 }
@@ -62,6 +64,14 @@ function _M.validate_request(ctx)
             return nil, err
         end
 
+        if ctx.ai_client_protocol == "claude" then
+            local converted, err = claude_converter.convert_request(request_table)
+            if not converted then
+                return nil, err
+            end
+            request_table = converted
+        end
+
         return request_table, nil
 end
 
@@ -147,7 +157,16 @@ local function read_response(conf, ctx, res, response_filter)
                 ::CONTINUE::
             end
 
+            if ctx.ai_client_protocol == "claude" then
+                local converted = claude_converter.convert_sse_events(ctx, chunk)
+                if converted then
+                    chunk = converted
+                else
+                    goto NEXT_CHUNK
+                end
+            end
             plugin.lua_response_filter(ctx, res.headers, chunk)
+            ::NEXT_CHUNK::
         end
     end
 
@@ -208,6 +227,14 @@ local function read_response(conf, ctx, res, response_filter)
             ctx.var.llm_response_text = content_to_check
         end
     end
+    if ctx.ai_client_protocol == "claude" and res_body then
+        if res.status == 200 then
+            raw_res_body = core.json.encode(claude_converter.convert_response(res_body))
+        else
+            raw_res_body = core.json.encode(
+                claude_converter.convert_error_response(res.status, res_body))
+        end
+    end
     plugin.lua_response_filter(ctx, headers, raw_res_body)
 end
 

apisix/plugins/ai-proxy/base.lua

@@ -53,6 +53,11 @@ function _M.before_proxy(conf, ctx, on_error)
         local ai_instance = ctx.picked_ai_instance
         local ai_driver = require("apisix.plugins.ai-drivers." .. ai_instance.provider)
 
+        local is_claude = core.string.has_suffix(ctx.var.uri, "/v1/messages")
+        if is_claude then
+            ctx.ai_client_protocol = "claude"
+        end
+
         local request_body, err = ai_driver.validate_request(ctx)
         if not request_body then
             return 400, err