Merge pull request #20369 from cgiradkar/Issue-16759-docs

Define better error message for container name conflicts with external storage

cmd/podman/root.go

@@ -21,6 +21,7 @@ import (
 	"github.com/containers/podman/v4/pkg/domain/entities"
 	"github.com/containers/podman/v4/pkg/parallel"
 	"github.com/containers/podman/v4/version"
+	"github.com/containers/storage"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
@@ -632,7 +633,8 @@ func rootFlags(cmd *cobra.Command, podmanConfig *entities.PodmanConfig) {
 
 func formatError(err error) string {
 	var message string
-	if errors.Is(err, define.ErrOCIRuntime) {
+	switch {
+	case errors.Is(err, define.ErrOCIRuntime):
 		// OCIRuntimeErrors include the reason for the failure in the
 		// second to last message in the error chain.
 		message = fmt.Sprintf(
@@ -640,7 +642,9 @@ func formatError(err error) string {
 			define.ErrOCIRuntime.Error(),
 			strings.TrimSuffix(err.Error(), ": "+define.ErrOCIRuntime.Error()),
 		)
-	} else {
+	case errors.Is(err, storage.ErrDuplicateName):
+		message = fmt.Sprintf("Error: %s, or use --replace to instruct Podman to do so.", err.Error())
+	default:
 		if logrus.IsLevelEnabled(logrus.TraceLevel) {
 			message = fmt.Sprintf("Error: %+v", err)
 		} else {

libpod/container_internal.go

@@ -510,6 +510,11 @@ func (c *Container) setupStorage(ctx context.Context) error {
 		}
 	}
 	if containerInfoErr != nil {
+		if errors.Is(containerInfoErr, storage.ErrDuplicateName) {
+			if _, err := c.runtime.LookupContainer(c.config.Name); errors.Is(err, define.ErrNoSuchCtr) {
+				return fmt.Errorf("creating container storage: %w by an external entity", containerInfoErr)
+			}
+		}
 		return fmt.Errorf("creating container storage: %w", containerInfoErr)
 	}
 

test/system/030-run.bats

@@ -1311,4 +1311,29 @@ search               | $IMAGE           |
     run_podman rm -f -t0 $cid
 }
 
+@test "podman create container with conflicting name" {
+    local cname="$(random_string 10 | tr A-Z a-z)"
+    local output_msg_ext="^Error: .*: the container name \"$cname\" is already in use by .* You have to remove that container to be able to reuse that name: that name is already in use by an external entity, or use --replace to instruct Podman to do so."
+    local output_msg="^Error: .*: the container name \"$cname\" is already in use by .* You have to remove that container to be able to reuse that name: that name is already in use, or use --replace to instruct Podman to do so."
+    if is_remote; then
+        output_msg_ext="^Error: .*: the container name \"$cname\" is already in use by .* You have to remove that container to be able to reuse that name: that name is already in use by an external entity"
+        output_msg="^Error: .*: the container name \"$cname\" is already in use by .* You have to remove that container to be able to reuse that name: that name is already in use"
+    fi
+
+    # external container
+    buildah from --name $cname scratch
+
+    run_podman 125 create --name $cname $IMAGE
+    assert "$output" =~ "$output_msg_ext" "Trying to create two containers with same name"
+
+    run_podman container rm $cname
+
+    run_podman --noout create --name $cname $IMAGE
+
+    run_podman 125 create --name $cname $IMAGE
+    assert "$output" =~ "$output_msg" "Trying to create two containers with same name"
+
+    run_podman container rm $cname
+}
+
 # vim: filetype=sh