From 26109ee821cf355d7668d7e8905c27645483ae48 Mon Sep 17 00:00:00 2001
From: frekw <fredrik@warnsberg.se>
Date: Tue, 7 May 2024 16:52:55 +0200
Subject: [PATCH] Add `--reproducible` flag to `flux push artifact`

This makes the pushed artifact have the exact same hash if the contents
are the same.

E.g
```
flux push artifact oci://repo/image:tag1 --source deploy --revision="test" --path=deploy --reproducible
flux push artifact oci://repo/image:tag2 --source deploy --revision="test" --path=deploy --reproducible
```

will both result in the same sha hash, tagged with `tag1` and `tag2`.

This is useful when producing flux artifacts in a monorepo setup where
you don't want to unnecessarily push new artifacts unless something has
actually changed.

Signed-off-by: frekw <fredrik@warnsberg.se>
---
 cmd/flux/push_artifact.go | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/cmd/flux/push_artifact.go b/cmd/flux/push_artifact.go
index 228a826e..735b78d5 100644
--- a/cmd/flux/push_artifact.go
+++ b/cmd/flux/push_artifact.go
@@ -105,15 +105,16 @@ The command can read the credentials from '~/.docker/config.json' but they can a
 }
 
 type pushArtifactFlags struct {
-	path        string
-	source      string
-	revision    string
-	creds       string
-	provider    flags.SourceOCIProvider
-	ignorePaths []string
-	annotations []string
-	output      string
-	debug       bool
+	path         string
+	source       string
+	revision     string
+	creds        string
+	provider     flags.SourceOCIProvider
+	ignorePaths  []string
+	annotations  []string
+	output       string
+	debug        bool
+	reproducible bool
 }
 
 var pushArtifactArgs = newPushArtifactFlags()
@@ -135,6 +136,7 @@ func init() {
 	pushArtifactCmd.Flags().StringVarP(&pushArtifactArgs.output, "output", "o", "",
 		"the format in which the artifact digest should be printed, can be 'json' or 'yaml'")
 	pushArtifactCmd.Flags().BoolVarP(&pushArtifactArgs.debug, "debug", "", false, "display logs from underlying library")
+	pushArtifactCmd.Flags().BoolVar(&pushArtifactArgs.reproducible, "reproducible", false, "ensure reproducible image digests by setting the created timestamp to '1970-01-01T00:00:00Z'")
 
 	pushCmd.AddCommand(pushArtifactCmd)
 }
@@ -202,6 +204,11 @@ func pushArtifactCmdRun(cmd *cobra.Command, args []string) error {
 		Annotations: annotations,
 	}
 
+	if pushArtifactArgs.reproducible {
+		zeroTime := time.Unix(0, 0)
+		meta.Created = zeroTime.Format(time.RFC3339)
+	}
+
 	ctx, cancel := context.WithTimeout(context.Background(), rootArgs.timeout)
 	defer cancel()