llmgw/internal/router/adapter_test.go

package router

import (
	"encoding/json"
	"net/http"
	"testing"

	"gitea.mynodes.xyz/ilker/llmgw/internal/auth"
	"gitea.mynodes.xyz/ilker/llmgw/internal/config"
	"gitea.mynodes.xyz/ilker/llmgw/internal/control/catalog"
	"gitea.mynodes.xyz/ilker/llmgw/internal/store"
)

func adapterModel() catalog.Model {
	m := catModel("coder", nil)
	m.Profiles = []catalog.Profile{{Name: "cpu", Engine: "llamacpp", MinMemoryGB: 4}}
	m.Adapters = []catalog.Adapter{
		{Name: "coder-sql", Source: "http://mirror/sql.gguf"},
		{Name: "coder-docs", Source: "http://mirror/docs.gguf", Scale: 0.5},
	}
	return m
}

func TestAnAdapterIsAskedForByNameAndAppliedOnItsModel(t *testing.T) {
	e := newFakeEngine(t, "coder")
	cfg := baseConfig(config.Endpoint{ID: "a", URL: e.srv.URL, Models: []string{"coder"}})
	cfg.Models = []catalog.Model{adapterModel()}
	rt := newTestRouter(t, cfg)

	sent := func(model string) map[string]any {
		t.Helper()
		rec := post(t, rt.Handler(), map[string]any{"model": model, "messages": []any{}}, nil)
		if rec.Code != http.StatusOK {
			t.Fatalf("%s: status %d: %s", model, rec.Code, rec.Body.String())
		}
		var body map[string]any
		_ = json.Unmarshal(e.last.Load().([]byte), &body)
		return body
	}
	body := sent("coder-docs")
	if body["model"] != "coder" {
		t.Errorf("the engine was asked for %v, not the model the adapter runs on", body["model"])
	}
	lora, _ := json.Marshal(body["lora"])
	if string(lora) != `[{"id":1,"scale":0.5}]` {
		t.Errorf("lora %s, expected the second adapter at its scale", lora)
	}
	if body := sent("coder-sql"); func() string { b, _ := json.Marshal(body["lora"]); return string(b) }() != `[{"id":0,"scale":1}]` {
		t.Errorf("the first adapter, at the default scale: %v", body["lora"])
	}
	if body := sent("coder"); body["lora"] != nil {
		t.Errorf("the base model was sent an adapter: %v", body["lora"])
	}
}

func TestAKeyAllowedAnAdapterReachesThatAdapterOnly(t *testing.T) {
	cfg := baseConfig()
	cfg.Models = []catalog.Model{adapterModel()}
	rt := newTestRouter(t, cfg)
	key := func(allowed ...string) auth.Principal {
		return auth.Principal{Limits: store.Effective{AllowedModels: allowed}}
	}
	for _, c := range []struct {
		allowed   []string
		requested string
		want      bool
	}{
		{[]string{"coder-sql"}, "coder-sql", true},
		{[]string{"coder-sql"}, "coder", false},
		{[]string{"coder-sql"}, "coder-docs", false},
		{[]string{"coder"}, "coder-sql", true}, // the model allows its adapters
		{[]string{"coder"}, "coder", true},
	} {
		if got := rt.permits(key(c.allowed...), c.requested); got != c.want {
			t.Errorf("allowed %v, asked for %s: %v", c.allowed, c.requested, got)
		}
	}
}

func TestAdaptersShareTheNamespaceOfModels(t *testing.T) {
	a := adapterModel()
	b := catModel("coder-sql", nil)
	if _, err := catalog.New([]catalog.Model{a, b}); err == nil {
		t.Error("an adapter named like another model was accepted")
	}
	bad := adapterModel()
	bad.Profiles = []catalog.Profile{{Name: "gpu", Engine: "vllm", GPUClass: "h100-80g", TP: 1}}
	if _, err := catalog.New([]catalog.Model{bad}); err == nil {
		t.Error("adapters on a vLLM profile were accepted")
	}
	c, err := catalog.New([]catalog.Model{adapterModel()})
	if err != nil {
		t.Fatal(err)
	}
	if m, ad, i, ok := c.ResolveAdapter("coder-docs"); !ok || m.Name != "coder" || i != 1 || ad.EffectiveScale() != 0.5 {
		t.Errorf("resolve: %v %+v %d %v", m.Name, ad, i, ok)
	}
}