podman diff accept two images or containers

First, make podman diff accept optionally a second argument. This allows
the user to specify a second image/container to compare the first with.
If it is not set the parent layer will be used as before.

Second, podman container diff should only use containers and podman
image diff should only use images. Previously, podman container diff
would use the image when both an image and container with this name
exists.

To make this work two new parameters have been added to the api. If they
are not used the previous behaviour is used. The same applies to the
bindings.

Fixes #10649

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

1 files changed, 26 insertions, 1 deletions

diff --git a/pkg/api/handlers/compat/changes.go b/pkg/api/handlers/compat/changes.go
index c442abbf9..dfe656755 100644
--- a/pkg/api/handlers/compat/changes.go
+++ b/pkg/api/handlers/compat/changes.go
@@ -4,14 +4,39 @@ import (
 	"net/http"
 
 	"github.com/containers/podman/v3/libpod"
+	"github.com/containers/podman/v3/libpod/define"
 	"github.com/containers/podman/v3/pkg/api/handlers/utils"
+	"github.com/gorilla/schema"
+	"github.com/pkg/errors"
 )
 
 func Changes(w http.ResponseWriter, r *http.Request) {
+	decoder := r.Context().Value("decoder").(*schema.Decoder)
 	runtime := r.Context().Value("runtime").(*libpod.Runtime)
 
+	query := struct {
+		Parent   string `schema:"parent"`
+		DiffType string `schema:"diffType"`
+	}{}
+	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
+		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
+		return
+	}
+	var diffType define.DiffType
+	switch query.DiffType {
+	case "", "all":
+		diffType = define.DiffAll
+	case "container":
+		diffType = define.DiffContainer
+	case "image":
+		diffType = define.DiffImage
+	default:
+		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Errorf("invalid diffType value %q", query.DiffType))
+		return
+	}
+
 	id := utils.GetName(r)
-	changes, err := runtime.GetDiff("", id)
+	changes, err := runtime.GetDiff(query.Parent, id, diffType)
 	if err != nil {
 		utils.InternalServerError(w, err)
 		return