Unify image inspection

Doesn't make sense to fork skopeo for this.

Signed-off-by: Colin Walters <walters@verbum.org>

Author: cgwalters

Cargo.lock

@@ -46,6 +46,7 @@ camino = "1.1.12"
 comfy-table = "7.1"
 strum = { version = "0.26", features = ["derive"] }
 quick-xml = "0.36"
+oci-spec = "0.8.2"
 
 [dev-dependencies]
 similar-asserts = "1.5"

crates/kit/Cargo.toml

@@ -106,6 +106,9 @@ pub struct ImageInspect {
     /// SHA256 image identifier
     pub id: String,
 
+    /// Image digest
+    pub digest: oci_spec::image::Digest,
+
     /// Image size in bytes
     pub size: u64,
 
@@ -232,35 +235,6 @@ pub fn get_image_size(name: &str) -> Result<u64> {
     Ok(info.size)
 }
 
-/// Get container image digest (sha256) for caching purposes.
-/// Returns the digest in the format "sha256:abc123..."
-pub fn get_image_digest(name: &str) -> Result<String> {
-    tracing::debug!("Getting digest for image: {}", name);
-
-    // Use skopeo inspect to get the manifest digest, which is more reliable than podman
-    // for getting the actual @sha256 digest that can be used for caching
-    let output = hostexec::command("skopeo", None)?
-        .args(["inspect", &format!("containers-storage:{}", name)])
-        .run_and_parse_json::<serde_json::Value>()
-        .map_err(|e| eyre!("Failed to inspect image with skopeo: {}", e))?;
-
-    // Extract the digest from the skopeo output
-    if let Some(digest) = output.get("Digest").and_then(|d| d.as_str()) {
-        tracing::debug!("Found image digest: {}", digest);
-        Ok(digest.to_string())
-    } else {
-        // Fall back to podman image inspect
-        tracing::debug!("No digest in skopeo output, falling back to podman inspect");
-        let info = inspect(name)?;
-        // Podman ID is already in sha256:xxx format
-        if info.id.starts_with("sha256:") {
-            Ok(info.id)
-        } else {
-            Ok(format!("sha256:{}", info.id))
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;

crates/kit/src/images.rs

@@ -200,7 +200,8 @@ impl LibvirtCreateOpts {
         }
 
         // It's a container image, check for cached volume
-        let image_digest = images::get_image_digest(&self.volume_name_or_image)?;
+        let image = images::inspect(&self.volume_name_or_image)?;
+        let image_digest = image.digest.to_string();
 
         if let Some(cached_volume) = self.find_cached_volume(global_opts, &image_digest)? {
             debug!("Using cached volume: {}", cached_volume);

crates/kit/src/libvirt/create.rs

@@ -188,7 +188,8 @@ pub fn run(global_opts: &crate::libvirt::LibvirtOptions, opts: LibvirtUploadOpts
     );
 
     // Phase 1: Extract image digest for caching
-    let image_digest = images::get_image_digest(&opts.source_image)?;
+    let inspect = images::inspect(&opts.source_image)?;
+    let image_digest = &inspect.digest.to_string();
     debug!("Container image digest: {}", image_digest);
 
     // Phase 2: Calculate disk size to use