export: Add progress flag

This is a very slow operation and it'd be really
nice to have progress.

Unfortunately we don't have a sane way to propagate status from
`skopeo copy`, so add an option to just output to stdout,
which is usable now in bootc.

Signed-off-by: Colin Walters <[email protected]>

lib/src/container/encapsulate.rs

@@ -330,6 +330,7 @@ async fn build_impl(
             dest,
             authfile.as_deref(),
             Some((std::sync::Arc::new(tempdir.try_clone()?.into()), target_fd)),
+            false,
         )
         .await?;
         Some(digest)

lib/src/container/skopeo.rs

@@ -67,10 +67,14 @@ pub(crate) async fn copy(
     dest: &ImageReference,
     authfile: Option<&Path>,
     add_fd: Option<(std::sync::Arc<OwnedFd>, i32)>,
+    progress: bool,
 ) -> Result<String> {
     let digestfile = tempfile::NamedTempFile::new()?;
     let mut cmd = new_cmd();
-    cmd.stdout(std::process::Stdio::null()).arg("copy");
+    cmd.arg("copy");
+    if !progress {
+        cmd.stdout(std::process::Stdio::null());
+    }
     cmd.arg("--digestfile");
     cmd.arg(digestfile.path());
     if let Some((add_fd, n)) = add_fd {

lib/src/container/store.rs

@@ -1221,6 +1221,8 @@ pub struct ExportToOCIOpts {
     pub skip_compression: bool,
     /// Path to Docker-formatted authentication file.
     pub authfile: Option<std::path::PathBuf>,
+    /// Output progress to stdout
+    pub progress_to_stdout: bool,
 }
 
 /// The way we store "chunk" layers in ostree is by writing a commit
@@ -1358,19 +1360,20 @@ pub async fn export(
     dest_imgref: &ImageReference,
     opts: Option<ExportToOCIOpts>,
 ) -> Result<String> {
+    let opts = opts.unwrap_or_default();
     let target_oci = dest_imgref.transport == Transport::OciDir;
     let tempdir = if !target_oci {
         let vartmp = cap_std::fs::Dir::open_ambient_dir("/var/tmp", cap_std::ambient_authority())?;
         let td = cap_std_ext::cap_tempfile::TempDir::new_in(&vartmp)?;
         // Always skip compression when making a temporary copy
         let opts = ExportToOCIOpts {
             skip_compression: true,
+            progress_to_stdout: opts.progress_to_stdout,
             ..Default::default()
         };
         export_to_oci(repo, src_imgref, &td, None, opts)?;
         td
     } else {
-        let opts = opts.unwrap_or_default();
         let (path, tag) = parse_oci_path_and_tag(dest_imgref.name.as_str());
         tracing::debug!("using OCI path={path} tag={tag:?}");
         let path = Dir::open_ambient_dir(path, cap_std::ambient_authority())
@@ -1384,12 +1387,13 @@ pub async fn export(
         transport: Transport::OciDir,
         name: format!("/proc/self/fd/{target_fd}"),
     };
-    let authfile = opts.as_ref().and_then(|o| o.authfile.as_deref());
+    let authfile = opts.authfile.as_deref();
     skopeo::copy(
         &tempoci,
         dest_imgref,
         authfile,
         Some((std::sync::Arc::new(tempdir.try_clone()?.into()), target_fd)),
+        opts.progress_to_stdout,
     )
     .await
 }

lib/src/container/update_detachedmeta.rs

@@ -29,7 +29,7 @@ pub async fn update_detached_metadata(
     };
 
     // Full copy of the source image
-    let pulled_digest: String = skopeo::copy(src, &tempsrc_ref, None, None)
+    let pulled_digest: String = skopeo::copy(src, &tempsrc_ref, None, None, false)
         .await
         .context("Creating temporary copy to OCI dir")?;
 
@@ -124,7 +124,7 @@ pub async fn update_detached_metadata(
 
     // Finally, copy the mutated image back to the target.  For chunked images,
     // because we only changed one layer, skopeo should know not to re-upload shared blobs.
-    crate::container::skopeo::copy(&tempsrc_ref, dest, None, None)
+    crate::container::skopeo::copy(&tempsrc_ref, dest, None, None, false)
         .await
         .context("Copying to destination")
 }