httptransport: return Accepted when not ready

This has the HTTP layer return Accepted (202) when the underlying
service reports it's not initialized.

Signed-off-by: Hank Donnay <hdonnay@redhat.com>

httptransport/vulnerabilityreporthandler.go

@@ -51,6 +51,20 @@ func VulnerabilityReportHandler(service matcher.Service, indexer indexer.Service
 			return
 		}
 
+		initd, err := service.Initialized(ctx)
+		if err != nil {
+			resp := &je.Response{
+				Code:    "internal-server-error",
+				Message: err.Error(),
+			}
+			je.Error(w, resp, http.StatusInternalServerError)
+			return
+		}
+		if !initd {
+			w.WriteHeader(http.StatusAccepted)
+			return
+		}
+
 		indexReport, ok, err := indexer.IndexReport(ctx, manifest)
 		// check err first
 		if err != nil {

httptransport/vulnerabilityreporthandler_test.go

@@ -0,0 +1,58 @@
+package httptransport
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/quay/claircore"
+
+	"github.com/quay/clair/v4/indexer"
+	"github.com/quay/clair/v4/matcher"
+)
+
+func TestInitialized(t *testing.T) {
+	var initd bool
+	digest := claircore.MustParseDigest("sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")
+	h := VulnerabilityReportHandler(
+		&matcher.Mock{
+			Initialized_: func(_ context.Context) (bool, error) {
+				return initd, nil
+			},
+		},
+		&indexer.Mock{
+			IndexReport_: func(ctx context.Context, d claircore.Digest) (*claircore.IndexReport, bool, error) {
+				if got, want := d.String(), digest.String(); got != want {
+					return nil, false, fmt.Errorf("unexpected digest: %v", got)
+				}
+				return nil, false, nil
+			},
+		},
+	)
+	srv := httptest.NewServer(h)
+	defer srv.Close()
+	c := srv.Client()
+
+	res, err := c.Get(srv.URL + "/" + digest.String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer res.Body.Close()
+	t.Log(res.Status)
+	if res.StatusCode != http.StatusAccepted {
+		t.Errorf("unexpected response")
+	}
+
+	initd = true
+	res, err = c.Get(srv.URL + "/" + digest.String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer res.Body.Close()
+	t.Log(res.Status)
+	if res.StatusCode != http.StatusNotFound {
+		t.Errorf("unexpected response")
+	}
+}