fix(ai-proxy): analytics missing when model is cjson.null

changelog/unreleased/kong/ai-proxy-azure-streaming copy.yml

@@ -0,0 +1,5 @@
+message: |
+  **AI-proxy-plugin**: Fix a bug where setting OpenAI SDK model parameter "null" caused analytics 
+  to not be written to the logging plugin(s).
+scope: Plugin
+type: bugfix

kong/plugins/ai-proxy/handler.lua

@@ -334,7 +334,9 @@ function _M:access(conf)
 
   -- copy from the user request if present
   if (not multipart) and (not conf_m.model.name) and (request_table.model) then
-    conf_m.model.name = request_table.model
+    if request_table.model ~= cjson.null then
+      conf_m.model.name = request_table.model
+    end
   elseif multipart then
     conf_m.model.name = "NOT_SPECIFIED"
   end
@@ -351,7 +353,6 @@ function _M:access(conf)
     return bad_request("model parameter not found in request, nor in gateway configuration")
   end
 
-  -- stash for analytics later
   kong_ctx_plugin.llm_model_requested = conf_m.model.name
 
   -- check the incoming format is the same as the configured LLM format

spec/03-plugins/38-ai-proxy/02-openai_integration_spec.lua

@@ -841,6 +841,37 @@ for _, strategy in helpers.all_strategies() do if strategy ~= "cassandra" then
         }, json.choices[1].message)
       end)
 
+      it("good request, parses model of cjson.null", function()
+        local body = pl_file.read("spec/fixtures/ai-proxy/openai/llm-v1-chat/requests/good.json")
+        body = cjson.decode(body)
+        body.model = cjson.null
+        body = cjson.encode(body)
+
+        local r = client:get("/openai/llm/v1/chat/good", {
+          headers = {
+            ["content-type"] = "application/json",
+            ["accept"] = "application/json",
+          },
+          body = body,
+        })
+
+        -- validate that the request succeeded, response status 200
+        local body = assert.res_status(200 , r)
+        local json = cjson.decode(body)
+
+        -- check this is in the 'kong' response format
+        assert.equals(json.id, "chatcmpl-8T6YwgvjQVVnGbJ2w8hpOA17SeNy2")
+        assert.equals(json.model, "gpt-3.5-turbo-0613")
+        assert.equals(json.object, "chat.completion")
+
+        assert.is_table(json.choices)
+        assert.is_table(json.choices[1].message)
+        assert.same({
+          content = "The sum of 1 + 1 is 2.",
+          role = "assistant",
+        }, json.choices[1].message)
+      end)
+
       it("tries to override configured model", function()
         local r = client:get("/openai/llm/v1/chat/good", {
           headers = {