reinstall: Pull podman image early

This splits the `podman pull <image>` and the
`podman ... bootc install to-existing` command to prepare for
future features that will require inspecting the image before
constructing the bootc install command.

Signed-off-by: ckyrouac <[email protected]>

Author: ckyrouac

system-reinstall-bootc/src/main.rs

@@ -20,6 +20,16 @@ fn run() -> Result<()> {
 
     let config = config::ReinstallConfig::load().context("loading config")?;
 
+    podman::ensure_podman_installed()?;
+
+    //pull image early so it can be inspected, e.g. to check for cloud-init
+    let mut pull_image_command = podman::pull_image_command(&config.bootc_image);
+    pull_image_command
+        .run_with_cmd_context()
+        .context(format!("pulling image {}", &config.bootc_image))?;
+
+    println!();
+
     let ssh_key_file = tempfile::NamedTempFile::new()?;
     let ssh_key_file_path = ssh_key_file
         .path()
@@ -30,18 +40,14 @@ fn run() -> Result<()> {
 
     prompt::get_ssh_keys(ssh_key_file_path)?;
 
-    let mut reinstall_podman_command = podman::command(&config.bootc_image, ssh_key_file_path);
+    let mut reinstall_podman_command =
+        podman::reinstall_command(&config.bootc_image, ssh_key_file_path);
 
     println!();
-
     println!("Going to run command {:?}", reinstall_podman_command);
 
     prompt::temporary_developer_protection_prompt()?;
 
-    // At this poihnt, the user has already given us permission to reinstall their system, so we
-    // feel confident with just installing podman without any further user interaction.
-    podman::ensure_podman_installed()?;
-
     reinstall_podman_command
         .run_with_cmd_context()
         .context("running reinstall command")?;

system-reinstall-bootc/src/podman.rs

@@ -4,7 +4,7 @@ use bootc_utils::CommandRunExt;
 use std::process::Command;
 use which::which;
 
-pub(crate) fn command(image: &str, ssh_key_file: &str) -> Command {
+pub(crate) fn reinstall_command(image: &str, ssh_key_file: &str) -> Command {
     let mut podman_command_and_args = [
         // We use podman to run the bootc container. This might change in the future to remove the
         // podman dependency.
@@ -62,6 +62,12 @@ pub(crate) fn command(image: &str, ssh_key_file: &str) -> Command {
     command
 }
 
+pub(crate) fn pull_image_command(image: &str) -> Command {
+    let mut command = Command::new("podman");
+    command.args(["pull", image]);
+    command
+}
+
 /// Path to the podman installation script. Can be influenced by the build
 /// SYSTEM_REINSTALL_BOOTC_INSTALL_PODMAN_PATH parameter to override. Defaults
 /// to /usr/lib/system-reinstall-bootc/install-podman