Augment IsOfflineError(err) so that it detects if the hishtory server is down, and will then treat all API errors as offline errors

backend/server/internal/server/api_handlers.go

@@ -308,3 +308,7 @@ func (s *Server) feedbackHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Length", "0")
 	w.WriteHeader(http.StatusOK)
 }
+
+func (s *Server) pingHandler(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte("OK"))
+}

backend/server/internal/server/srv.go

@@ -107,6 +107,7 @@ func (s *Server) Run(ctx context.Context, addr string) error {
 	mux.Handle("/api/v1/add-deletion-request", loggerMiddleware(s.addDeletionRequestHandler))
 	mux.Handle("/api/v1/slsa-status", loggerMiddleware(s.slsaStatusHandler))
 	mux.Handle("/api/v1/feedback", loggerMiddleware(s.feedbackHandler))
+	mux.Handle("/api/v1/ping", loggerMiddleware(s.pingHandler))
 	mux.Handle("/healthcheck", loggerMiddleware(s.healthCheckHandler))
 	mux.Handle("/internal/api/v1/usage-stats", loggerMiddleware(s.usageStatsHandler))
 	mux.Handle("/internal/api/v1/stats", loggerMiddleware(s.statsHandler))

client/lib/lib.go

@@ -496,7 +496,7 @@ func IsOfflineError(err error) bool {
 	if err == nil {
 		return false
 	}
-	return strings.Contains(err.Error(), "dial tcp: lookup api.hishtory.dev") ||
+	if strings.Contains(err.Error(), "dial tcp: lookup api.hishtory.dev") ||
 		strings.Contains(err.Error(), "connect: network is unreachable") ||
 		strings.Contains(err.Error(), "read: connection reset by peer") ||
 		strings.Contains(err.Error(), ": EOF") ||
@@ -505,7 +505,20 @@ func IsOfflineError(err error) bool {
 		strings.Contains(err.Error(), ": i/o timeout") ||
 		strings.Contains(err.Error(), "connect: operation timed out") ||
 		strings.Contains(err.Error(), "net/http: TLS handshake timeout") ||
-		strings.Contains(err.Error(), "connect: connection refused")
+		strings.Contains(err.Error(), "connect: connection refused") {
+		return true
+	}
+	if !isHishtoryServerUp() {
+		// If the backend server is down, then treat all errors as offline errors
+		return true
+	}
+	// A truly unexpected error, bubble this up
+	return false
+}
+
+func isHishtoryServerUp() bool {
+	_, err := ApiGet("/api/v1/ping")
+	return err == nil
 }
 
 func normalizeEntryTimezone(entry data.HistoryEntry) data.HistoryEntry {

client/lib/lib_test.go

@@ -1,6 +1,7 @@
 package lib
 
 import (
+	"fmt"
 	"os"
 	"path"
 	"reflect"
@@ -11,6 +12,7 @@ import (
 	"github.com/ddworken/hishtory/client/hctx"
 	"github.com/ddworken/hishtory/shared"
 	"github.com/ddworken/hishtory/shared/testutils"
+	"github.com/stretchr/testify/require"
 )
 
 func TestSetup(t *testing.T) {
@@ -355,3 +357,16 @@ func TestSplitEscaped(t *testing.T) {
 		}
 	}
 }
+
+func TestAugmentedIsOfflineError(t *testing.T) {
+	defer testutils.BackupAndRestoreEnv("HISHTORY_SIMULATE_NETWORK_ERROR")()
+
+	// By default, when the hishtory server is up, then IsOfflineError checks the error msg
+	require.True(t, isHishtoryServerUp())
+	require.False(t, IsOfflineError(fmt.Errorf("unchecked error type")))
+
+	// When the hishtory server is down, then all error messages are treated as being due to offline errors
+	os.Setenv("HISHTORY_SIMULATE_NETWORK_ERROR", "1")
+	require.False(t, isHishtoryServerUp())
+	require.True(t, IsOfflineError(fmt.Errorf("unchecked error type")))
+}