fix(dst): correct error messages

test/dst/model.go

@@ -1,6 +1,7 @@
 package dst
 
 import (
+	"errors"
 	"fmt"
 	"regexp"
 	"strings"
@@ -73,15 +74,17 @@ func (m *Model) addCursor(next *t_api.Request) {
 
 func (m *Model) Step(req *t_api.Request, res *t_api.Response, err error) error {
 	if err != nil {
-		switch err.Error() {
-		case "api submission queue full":
-			return nil
-		case "subsystem:store:sqlite submission queue full":
+		var resErr *t_api.ResonateError
+		if !errors.As(err, &resErr) {
+			return fmt.Errorf("unexpected non-resonate error '%v'", err)
+		}
+		switch resErr.Code() {
+		case t_api.ErrAPISubmissionQueueFull:
 			return nil
-		case "subsystem:network:dst submission queue full":
+		case t_api.ErrAIOSubmissionQueueFull:
 			return nil
 		default:
-			return fmt.Errorf("unexpected error '%v'", err)
+			return fmt.Errorf("unexpected resonate error '%v'", resErr)
 		}
 	}
 

test/dst/model_test.go

@@ -0,0 +1,64 @@
+package dst
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/resonatehq/resonate/internal/kernel/t_api"
+	"github.com/stretchr/testify/require"
+)
+
+func TestModelStep(t *testing.T) {
+	tcs := []struct {
+		name    string
+		m       *Model
+		req     *t_api.Request
+		res     *t_api.Response
+		err     error
+		wantErr bool
+	}{
+		{
+			name:    "api submission queue full error",
+			m:       &Model{},
+			req:     &t_api.Request{},
+			res:     &t_api.Response{},
+			err:     t_api.NewResonateError(t_api.ErrAPISubmissionQueueFull, "", nil),
+			wantErr: false,
+		},
+		{
+			name:    "aio submission queue full error",
+			m:       &Model{},
+			req:     &t_api.Request{},
+			res:     &t_api.Response{},
+			err:     t_api.NewResonateError(t_api.ErrAIOSubmissionQueueFull, "", nil),
+			wantErr: false,
+		},
+		{
+			name:    "unexpected resonate error",
+			m:       &Model{},
+			req:     &t_api.Request{},
+			res:     &t_api.Response{},
+			err:     t_api.NewResonateError(-1, "", nil),
+			wantErr: true,
+		},
+		{
+			name:    "unexpected non-resonate error",
+			m:       &Model{},
+			req:     &t_api.Request{},
+			res:     &t_api.Response{},
+			err:     errors.New("unexpected non-resonate error"),
+			wantErr: true,
+		},
+	}
+
+	for _, tc := range tcs {
+		t.Run(tc.name, func(t *testing.T) {
+			err := tc.m.Step(tc.req, tc.res, tc.err)
+			if tc.wantErr {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}