From 16bd07623231fa120bdbbc46531e66ad7f011905 Mon Sep 17 00:00:00 2001
From: Ryan Bottriell <ryan@bottriell.ca>
Date: Fri, 1 Mar 2024 09:58:33 -0800
Subject: [PATCH] Add flag to follow refs in info command

This is something that I regularly bump into, where I have a layer
digest, but want to see the contents of the manifest. Rather than
needing to copy and paste the digest into the info command again, this
will follow each child reference down to the manifest and print them
all.

Signed-off-by: Ryan Bottriell <ryan@bottriell.ca>
---
 crates/spfs-cli/main/src/cmd_info.rs | 47 +++++++++++++++-------------
 1 file changed, 26 insertions(+), 21 deletions(-)

diff --git a/crates/spfs-cli/main/src/cmd_info.rs b/crates/spfs-cli/main/src/cmd_info.rs
index 7fc6af3a05..549eac00f9 100644
--- a/crates/spfs-cli/main/src/cmd_info.rs
+++ b/crates/spfs-cli/main/src/cmd_info.rs
@@ -2,6 +2,8 @@
 // SPDX-License-Identifier: Apache-2.0
 // https://github.com/imageworks/spk
 
+use std::collections::VecDeque;
+
 use clap::Args;
 use colored::*;
 use miette::Result;
@@ -40,31 +42,36 @@ pub struct CmdInfo {
     /// Use shortened digests in the output (nicer, but slower)
     #[clap(long)]
     short: bool,
+
+    /// Follow and show child objects, depth-first
+    #[clap(long)]
+    follow: bool,
+
+    /// Remaining refs to process, used to handle recursive
+    /// --follow behavior at runtime
+    #[clap(skip)]
+    to_process: VecDeque<String>,
 }
 
 impl CmdInfo {
     pub async fn run(&mut self, config: &spfs::Config) -> Result<i32> {
         let repo = spfs::config::open_repository_from_string(config, self.remote.as_ref()).await?;
 
-        if self.refs.is_empty() {
+        self.to_process.extend(self.refs.iter().cloned());
+
+        if self.to_process.is_empty() {
             self.print_global_info(&repo).await?;
         } else {
-            let number_refs = self.refs.len();
-            for (index, reference) in self.refs.iter().enumerate() {
+            while let Some(reference) = self.to_process.pop_front() {
                 if reference.starts_with(spfs::env::SPFS_DIR) {
-                    self.pretty_print_file(
-                        reference,
-                        &repo,
-                        self.logging.verbose as usize,
-                        number_refs,
-                    )
-                    .await?;
+                    self.pretty_print_file(&reference, &repo, self.logging.verbose as usize)
+                        .await?;
                 } else {
                     let item = repo.read_ref(reference.as_str()).await?;
                     self.pretty_print_ref(item, &repo, self.logging.verbose as usize)
                         .await?;
                 }
-                if index + 1 < number_refs {
+                if !self.to_process.is_empty() {
                     println!();
                 }
             }
@@ -92,7 +99,7 @@ impl CmdInfo {
 
     /// Display the spfs object locations that provide the given file
     async fn pretty_print_ref(
-        &self,
+        &mut self,
         obj: spfs::graph::Object,
         repo: &spfs::storage::RepositoryHandle,
         verbosity: usize,
@@ -112,6 +119,9 @@ impl CmdInfo {
                 println!("{}:", "stack (top-down)".bright_blue());
                 for reference in obj.stack.to_top_down() {
                     println!("  - {}", self.format_digest(reference, repo).await?);
+                    if self.follow {
+                        self.to_process.push_back(reference.to_string());
+                    }
                 }
             }
 
@@ -131,6 +141,9 @@ impl CmdInfo {
                     "manifest:".bright_blue(),
                     self.format_digest(obj.manifest, repo).await?
                 );
+                if self.follow {
+                    self.to_process.push_back(obj.manifest.to_string());
+                }
             }
 
             Object::Manifest(obj) => {
@@ -224,7 +237,6 @@ impl CmdInfo {
         filepath: &str,
         repo: &spfs::storage::RepositoryHandle,
         verbosity: usize,
-        number_refs: usize,
     ) -> Result<()> {
         let mut in_a_runtime = true;
         let found = match spfs::find_path::find_path_providers_in_spfs_runtime(filepath, repo).await
@@ -251,16 +263,9 @@ impl CmdInfo {
             if let Some(first_path) = found.first() {
                 if let Some(ObjectPathEntry::FilePath(file_entry)) = first_path.last() {
                     let number = found.len();
-                    let query = if number_refs > 1 {
-                        format!("{filepath}: ")
-                    } else {
-                        "".to_string()
-                    };
                     println!(
-                        "{}{} (in {} {}{})",
-                        query,
+                        "{} (in {number} {}{})",
                         file_entry.kind.to_string().green(),
-                        number,
                         "layer".pluralize(number),
                         if verbosity < 1 && number > 1 {
                             ", topmost 1 shown, use -v to see all"