container: Add manifest/config to image query, add image history CLI

Extend our image state struct to include the manifest and image
configuration (if available, only in v1).

Add a `container image history` CLI verb which prints it.

lib/Cargo.toml

@@ -39,6 +39,7 @@ serde_json = "1.0.64"
 structopt = "0.3.21"
 tar = "0.4.38"
 tempfile = "3.2.0"
+term_size = "0.3.2"
 tokio = { features = ["full"], version = "1" }
 tokio-util = { features = ["io-util"], version = "0.6.9" }
 tokio-stream = { features = ["sync"], version = "0.1.8" }

lib/src/cli.rs

@@ -188,6 +188,17 @@ enum ContainerImageOpts {
  proxyopts: ContainerProxyOpts,
  },
 
+ /// Pull (or update) a container image.
+ History {
+ /// Path to the repository
+ #[structopt(long, parse(try_from_str = parse_repo))]
+ repo: ostree::Repo,
+
+ /// Image reference, e.g. ostree-remote-image:someremote:registry:quay.io/exampleos/exampleos:latest
+ #[structopt(parse(try_from_str = parse_imgref))]
+ imgref: OstreeImageReference,
+ },
+
  /// Copy a pulled container image from one repo to another.
  Copy {
  /// Path to the source repository
@@ -467,6 +478,63 @@ async fn container_store(
  Ok(())
 }
 
+fn print_column(s: &str, clen: usize, remaining: &mut usize) {
+ let l = s.len().min(*remaining);
+ print!("{}", &s[0..l]);
+ if clen > 0 {
+ // We always want two trailing spaces
+ let pad = clen.saturating_sub(l) + 2;
+ for _ in 0..pad {
+ print!(" ");
+ }
+ *remaining = remaining.checked_sub(l + pad).unwrap();
+ }
+}
+
+/// Output the container image history
+async fn container_history(repo: &ostree::Repo, imgref: &OstreeImageReference) -> Result<()> {
+ let img = crate::container::store::query_image(repo, imgref)?
+ .ok_or_else(|| anyhow::anyhow!("No such image: {}", imgref))?;
+ let columns = [("ID", 20), ("SIZE", 10), ("CREATED BY", 0usize)];
+ let width = term_size::dimensions().map(|x| x.0).unwrap_or(80);
+ if let Some(config) = img.configuration.as_ref() {
+ let mut history = config.history().iter();
+ let mut layers = img.manifest.layers().iter();
+
+ {
+ let mut remaining = width;
+ for (name, width) in columns.iter() {
+ print_column(name, *width as usize, &mut remaining);
+ }
+ println!();
+ }
+
+ while let Some(v) = layers.next() {
+ let histent = history.next();
+ let created_by = histent
+ .map(|s| s.created_by().as_deref())
+ .flatten()
+ .unwrap_or("");
+
+ let mut remaining = width;
+
+ let digest = v.digest().as_str();
+ // Verify it's OK to slice, this should all be ASCII
+ assert!(digest.chars().all(|c| c.is_ascii()));
+ let digest_max = columns[0].1;
+ let digest = &digest[0..digest_max];
+ print_column(digest, digest_max, &mut remaining);
+ let size = glib::format_size(v.size() as u64);
+ print_column(size.as_str(), columns[1].1, &mut remaining);
+ print_column(created_by, columns[2].1, &mut remaining);
+ println!();
+ }
+ Ok(())
+ } else {
+ anyhow::bail!("v0 image does not have fetched configuration");
+ }
+}
+
 /// Add IMA signatures to an ostree commit, generating a new commit.
 fn ima_sign(cmdopts: &ImaSignOpts) -> Result<()> {
  let signopts = crate::ima::ImaOpts {
@@ -550,6 +618,9 @@ where
  imgref,
  proxyopts,
  } => container_store(&repo, &imgref, proxyopts).await,
+ ContainerImageOpts::History { repo, imgref } => {
+ container_history(&repo, &imgref).await
+ }
  ContainerImageOpts::Copy {
  src_repo,
  dest_repo,

lib/src/container/store.rs

@@ -65,6 +65,10 @@ pub struct LayeredImageState {
  pub is_layered: bool,
  /// The digest of the original manifest
  pub manifest_digest: String,
+ /// The image manfiest
+ pub manifest: ImageManifest,
+ /// The image configuration; for v0 images, may not be available.
+ pub configuration: Option<ImageConfiguration>,
 }
 
 impl LayeredImageState {
@@ -208,6 +212,16 @@ fn manifest_data_from_commitmeta(
  Ok((r, digest))
 }
 
+fn image_config_from_commitmeta(
+ commit_meta: &glib::VariantDict,
+) -> Result<Option<ImageConfiguration>> {
+ commit_meta
+ .lookup::<String>(META_CONFIG)?
+ .filter(|v| v != "null") // Format v0 apparently old versions injected `null` here sadly...
+ .map(|v| serde_json::from_str(&v).map_err(anyhow::Error::msg))
+ .transpose()
+}
+
 /// Return the original digest of the manifest stored in the commit metadata.
 /// This will be a string of the form e.g. `sha256:<digest>`.
 ///
@@ -293,15 +307,13 @@ impl ImageImporter {
  // Query for previous stored state
 
  let (previous_manifest_digest, previous_imageid) =
- if let Some((previous_manifest, previous_state)) =
- query_image_impl(&self.repo, &self.imgref)?
- {
+ if let Some(previous_state) = query_image(&self.repo, &self.imgref)? {
  // If the manifest digests match, we're done.
  if previous_state.manifest_digest == manifest_digest {
  return Ok(PrepareResult::AlreadyPresent(previous_state));
  }
  // Failing that, if they have the same imageID, we're also done.
- let previous_imageid = previous_manifest.config().digest().as_str();
+ let previous_imageid = previous_state.manifest.config().digest().as_str();
  if previous_imageid == new_imageid {
  return Ok(PrepareResult::AlreadyPresent(previous_state));
  }
@@ -598,10 +610,11 @@ pub fn list_images(repo: &ostree::Repo) -> Result<Vec<String>> {
  .collect()
 }
 
-fn query_image_impl(
+/// Query metadata for a pulled image.
+pub fn query_image(
  repo: &ostree::Repo,
  imgref: &OstreeImageReference,
-) -> Result<Option<(ImageManifest, LayeredImageState)>> {
+) -> Result<Option<LayeredImageState>> {
  let ostree_ref = &ref_for_image(&imgref.imgref)?;
  let merge_rev = repo.resolve_rev(ostree_ref, true)?;
  let (merge_commit, merge_commit_obj) = if let Some(r) = merge_rev {
@@ -612,6 +625,7 @@ fn query_image_impl(
  let commit_meta = &merge_commit_obj.child_value(0);
  let commit_meta = &ostree::glib::VariantDict::new(Some(commit_meta));
  let (manifest, manifest_digest) = manifest_data_from_commitmeta(commit_meta)?;
+ let configuration = image_config_from_commitmeta(commit_meta)?;
  let mut layers = manifest.layers().iter().cloned();
  // We require a base layer.
  let base_layer = layers.next().ok_or_else(|| anyhow!("No layers found"))?;
@@ -626,17 +640,11 @@ fn query_image_impl(
  merge_commit,
  is_layered,
  manifest_digest,
+ manifest,
+ configuration,
  };
  tracing::debug!(state = ?state);
- Ok(Some((manifest, state)))
-}
-
-/// Query metadata for a pulled image.
-pub fn query_image(
- repo: &ostree::Repo,
- imgref: &OstreeImageReference,
-) -> Result<Option<LayeredImageState>> {
- Ok(query_image_impl(repo, imgref)?.map(|v| v.1))
+ Ok(Some(state))
 }
 
 /// Copy a downloaded image from one repository to another.