install: Add print-configuration

.github/workflows/ci.yml

@@ -106,7 +106,7 @@ jobs:
     name: "Container testing"
     needs: build-fedora
     runs-on: ubuntu-latest
-    container: quay.io/fedora/fedora-coreos:testing-devel
+    container: quay.io/centos-bootc/fedora-bootc:eln
     steps:
       - name: Download
         uses: actions/download-artifact@v3

lib/src/cli.rs

@@ -118,6 +118,13 @@ pub(crate) enum InstallOpts {
     ToDisk(crate::install::InstallToDiskOpts),
     /// Install to the target filesystem
     ToFilesystem(crate::install::InstallToFilesystemOpts),
+    /// Output JSON to stdout that contains the merged installation configuration
+    /// as it may be relevant to calling processes using `install to-filesystem`
+    /// that want to honor e.g. `root-fs-type`.
+    ///
+    /// At the current time, the only output key is `root-fs-type` which is a string-valued
+    /// filesystem name suitable for passing to `mkfs.$type`.
+    PrintConfiguration,
 }
 
 /// Options for man page generation
@@ -522,6 +529,7 @@ async fn run_from_opt(opt: Opt) -> Result<()> {
         Opt::Install(opts) => match opts {
             InstallOpts::ToDisk(opts) => crate::install::install_to_disk(opts).await,
             InstallOpts::ToFilesystem(opts) => crate::install::install_to_filesystem(opts).await,
+            InstallOpts::PrintConfiguration => crate::install::print_configuration(),
         },
         #[cfg(feature = "install")]
         Opt::ExecInHostMountNamespace { args } => {

lib/src/install.rs

@@ -6,7 +6,7 @@
 
 // This sub-module is the "basic" installer that handles creating basic block device
 // and filesystem setup.
-mod baseline;
+pub(crate) mod baseline;
 
 use std::io::BufWriter;
 use std::io::Write;
@@ -429,6 +429,13 @@ impl SourceInfo {
     }
 }
 
+pub(crate) fn print_configuration() -> Result<()> {
+    let mut install_config = config::load_config()?;
+    install_config.filter_to_external();
+    let stdout = std::io::stdout().lock();
+    serde_json::to_writer(stdout, &install_config).map_err(Into::into)
+}
+
 pub(crate) mod config {
     use super::*;
 
@@ -447,6 +454,7 @@ pub(crate) mod config {
         /// Root filesystem type
         pub(crate) root_fs_type: Option<super::baseline::Filesystem>,
         /// Kernel arguments, applied at installation time
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub(crate) kargs: Option<Vec<String>>,
     }
 
@@ -465,6 +473,11 @@ pub(crate) mod config {
                     .extend(other_kargs)
             }
         }
+
+        // Remove all configuration which is handled by `install to-filesystem`.
+        pub(crate) fn filter_to_external(&mut self) {
+            self.kargs.take();
+        }
     }
 
     #[context("Loading configuration")]

lib/src/privtests.rs

@@ -1,12 +1,13 @@
 use std::process::Command;
 
-use anyhow::Result;
+use anyhow::{Context, Result};
 use camino::Utf8Path;
 use fn_error_context::context;
 use rustix::fd::AsFd;
 use xshell::{cmd, Shell};
 
 use crate::blockdev::LoopbackDevice;
+use crate::install::config::InstallConfiguration;
 
 use super::cli::TestingOpts;
 use super::spec::Host;
@@ -98,6 +99,14 @@ pub(crate) fn impl_run_container() -> Result<()> {
     let stderr = String::from_utf8(o.stderr)?;
     assert!(stderr.contains("requires root privileges"));
 
+    let config = cmd!(sh, "bootc install print-configuration").read()?;
+    let config: InstallConfiguration =
+        serde_json::from_str(&config).context("Parsing install config")?;
+    assert_eq!(
+        config.root_fs_type.unwrap(),
+        crate::install::baseline::Filesystem::Xfs
+    );
+
     println!("ok container integration testing");
     Ok(())
 }

manpages-md/bootc-install-print-configuration.md

@@ -0,0 +1,34 @@
+# NAME
+
+bootc-install-print-configuration - Output JSON to stdout that contains
+the merged installation configuration as it may be relevant to calling
+processes using \`install to-filesystem\` that want to honor e.g.
+\`root-fs-type\`
+
+# SYNOPSIS
+
+**bootc-install-print-configuration** \[**-h**\|**\--help**\]
+\[**-V**\|**\--version**\]
+
+# DESCRIPTION
+
+Output JSON to stdout that contains the merged installation
+configuration as it may be relevant to calling processes using \`install
+to-filesystem\` that want to honor e.g. \`root-fs-type\`.
+
+At the current time, the only output key is \`root-fs-type\` which is a
+string-valued filesystem name suitable for passing to \`mkfs.\$type\`.
+
+# OPTIONS
+
+**-h**, **\--help**
+
+:   Print help (see a summary with -h)
+
+**-V**, **\--version**
+
+:   Print version
+
+# VERSION
+
+v0.1.0

manpages-md/bootc-install-to-disk.md

@@ -5,11 +5,12 @@ bootc-install-to-disk - Install to the target block device
 # SYNOPSIS
 
 **bootc-install-to-disk** \[**\--wipe**\] \[**\--block-setup**\]
-\[**\--filesystem**\] \[**\--root-size**\] \[**\--target-transport**\]
-\[**\--target-imgref**\] \[**\--enforce-container-sigpolicy**\]
-\[**\--target-ostree-remote**\] \[**\--skip-fetch-check**\]
-\[**\--disable-selinux**\] \[**\--karg**\] \[**\--generic-image**\]
-\[**-h**\|**\--help**\] \[**-V**\|**\--version**\] \<*DEVICE*\>
+\[**\--filesystem**\] \[**\--root-size**\] \[**\--source-imgref**\]
+\[**\--target-transport**\] \[**\--target-imgref**\]
+\[**\--enforce-container-sigpolicy**\] \[**\--target-ostree-remote**\]
+\[**\--skip-fetch-check**\] \[**\--disable-selinux**\] \[**\--karg**\]
+\[**\--generic-image**\] \[**\--via-loopback**\] \[**-h**\|**\--help**\]
+\[**-V**\|**\--version**\] \<*DEVICE*\>
 
 # DESCRIPTION
 
@@ -45,6 +46,16 @@ unlock of filesystem to presence of the default tpm2 device.\
 
 By default, all remaining space on the disk will be used.
 
+**\--source-imgref**=*SOURCE_IMGREF*
+
+:   Install the system from an explicitly given source.
+
+By default, bootc install and install-to-filesystem assumes that it runs
+in a podman container, and it takes the container image to install from
+the podmans container registry. If \--source-imgref is given, bootc uses
+it as the installation source, instead of the behaviour explained in the
+previous paragraph. See skopeo(1) for accepted formats.
+
 **\--target-transport**=*TARGET_TRANSPORT* \[default: registry\]
 
 :   The transport; e.g. oci, oci-archive. Defaults to \`registry\`
@@ -94,6 +105,10 @@ disabled but where the target does have SELinux enabled.
 \- All bootloader types will be installed - Changes to the system
 firmware will be skipped
 
+**\--via-loopback**
+
+:   Instead of targeting a block device, write to a file via loopback
+
 **-h**, **\--help**
 
 :   Print help (see a summary with -h)

manpages-md/bootc-install-to-filesystem.md

@@ -6,11 +6,11 @@ bootc-install-to-filesystem - Install to the target filesystem
 
 **bootc-install-to-filesystem** \[**\--root-mount-spec**\]
 \[**\--root-options**\] \[**\--boot-mount-spec**\] \[**\--replace**\]
-\[**\--target-transport**\] \[**\--target-imgref**\]
-\[**\--enforce-container-sigpolicy**\] \[**\--target-ostree-remote**\]
-\[**\--skip-fetch-check**\] \[**\--disable-selinux**\] \[**\--karg**\]
-\[**\--generic-image**\] \[**-h**\|**\--help**\]
-\[**-V**\|**\--version**\] \<*ROOT_PATH*\>
+\[**\--source-imgref**\] \[**\--target-transport**\]
+\[**\--target-imgref**\] \[**\--enforce-container-sigpolicy**\]
+\[**\--target-ostree-remote**\] \[**\--skip-fetch-check**\]
+\[**\--disable-selinux**\] \[**\--karg**\] \[**\--generic-image**\]
+\[**-h**\|**\--help**\] \[**-V**\|**\--version**\] \<*ROOT_PATH*\>
 
 # DESCRIPTION
 
@@ -54,6 +54,16 @@ be used.
 >     However, the running system (and all files) will remain in place
 >     until reboot
 
+**\--source-imgref**=*SOURCE_IMGREF*
+
+:   Install the system from an explicitly given source.
+
+By default, bootc install and install-to-filesystem assumes that it runs
+in a podman container, and it takes the container image to install from
+the podmans container registry. If \--source-imgref is given, bootc uses
+it as the installation source, instead of the behaviour explained in the
+previous paragraph. See skopeo(1) for accepted formats.
+
 **\--target-transport**=*TARGET_TRANSPORT* \[default: registry\]
 
 :   The transport; e.g. oci, oci-archive. Defaults to \`registry\`

manpages-md/bootc-install.md

@@ -35,6 +35,12 @@ bootc-install-to-filesystem(8)
 
 :   Install to the target filesystem
 
+bootc-install-print-configuration(8)
+
+:   Output JSON to stdout that contains the merged installation
+    configuration as it may be relevant to calling processes using
+    \`install to-filesystem\` that want to honor e.g. \`root-fs-type\`
+
 bootc-install-help(8)
 
 :   Print this message or the help of the given subcommand(s)