Add cargo xtask and packaging infrastructure

First, this adds `cargo xtask` following
https://github.com/matklad/cargo-xtask/

We use this to write "external glue scripts" in Rust, not bash.
Specifically we now have e.g. `cargo xtask vendor` which just
wraps running `cargo vendor-filterer`.

Then build on that and add `cargo xtask package-srpm` which generates
a `.src.rpm`.

And build on that by adding the requisite glue to have Fedora's COPR
be able to understand it, so that we can get auto-built and shipped
packages there.

This will make trying out bootc a bit easier.

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

.cargo/config.toml

@@ -0,0 +1,2 @@
+[alias]
+xtask = "run --package xtask --"

.copr/Makefile

@@ -0,0 +1,7 @@
+srpm:
+	dnf -y install cargo git openssl-devel
+	# similar to https://github.com/actions/checkout/issues/760, but for COPR
+	git config --global --add safe.directory '*'
+	cargo install cargo-vendor-filterer
+	cargo xtask package-srpm
+	mv target/*.src.rpm $$outdir

.github/workflows/packaging.yml

@@ -0,0 +1,36 @@
+# This is an unused WIP.  Maybe we'll use it in the future
+# name: Packaging
+
+# permissions:
+#   actions: read
+
+# on:
+#   push:
+#     branches: [main]
+#   pull_request:
+#     branches: [main]
+#     types: [labeled, opened, synchronize, reopened]
+#   workflow_dispatch: {}
+
+# jobs:
+#   srpm:
+#     if: ${{ contains(github.event.pull_request.labels.*.name, 'ci/full') }}
+#     runs-on: ubuntu-latest
+#     container: quay.io/coreos-assembler/fcos-buildroot:testing-devel
+#     steps:
+#       - uses: actions/checkout@v3
+#       - name: Mark git checkout as safe
+#         run: git config --global --add safe.directory "$GITHUB_WORKSPACE"
+#       - name: Cache Dependencies
+#         uses: Swatinem/rust-cache@v2
+#         with:
+#           key: "srpm"
+#       - name: Install vendor tool
+#         run: cargo install cargo-vendor-filterer
+#       - name: Build
+#         run: cargo xtask package-srpm
+#       - name: Upload
+#         uses: actions/upload-artifact@v2
+#         with:
+#           name: bootc-srpm
+#           path: target/*.src.rpm

Cargo.toml

@@ -1,8 +1,21 @@
 [workspace]
-members = ["cli", "lib"]
+members = ["cli", "lib", "xtask"]
 
 [profile.dev]
 opt-level = 1 # No optimizations are too slow for us.
 
 [profile.release]
-lto = "thin"
+# RPMs/debs/etc want debuginfo by default
+debug = true
+
+# See https://github.com/coreos/cargo-vendor-filterer
+[workspace.metadata.vendor-filter]
+platforms = ["x86_64-unknown-linux-gnu", "aarch64-unknown-linux-gnu", "s390x-unknown-linux-gnu"]
+all-features = true
+exclude-crate-paths = [ { name = "libz-sys", exclude = "src/zlib" },
+                        { name = "libz-sys", exclude = "src/zlib-ng" },
+                        # rustix includes pre-generated assembly for linux_raw, which we don't use
+                        { name = "rustix", exclude = "src/imp/linux_raw" },
+                        # Test files that include binaries
+                        { name = "system-deps", exclude = "src/tests" },
+                      ]

Makefile

@@ -11,3 +11,11 @@ bin-archive: all
 
 install-kola-tests:
 	install -D -t $(DESTDIR)$(prefix)/lib/coreos-assembler/tests/kola/bootc tests/kolainst/basic
+
+vendor:
+	cargo xtask $@
+.PHONY: vendor
+
+package-rpm:
+	cargo xtask $@
+.PHONY: package-rpm

cli/Cargo.toml

@@ -7,6 +7,7 @@ repository = "https://github.com/cgwalters/bootc"
 readme = "README.md"
 publish = false
 rust-version = "1.63.0"
+default-run = "bootc"
 
 # See https://github.com/coreos/cargo-vendor-filterer
 [package.metadata.vendor-filter]
@@ -17,7 +18,7 @@ platforms = ["x86_64-unknown-linux-gnu", "aarch64-unknown-linux-gnu", "powerpc64
 
 [dependencies]
 anyhow = "1.0"
-bootc-lib = { path = "../lib" }
+bootc-lib = { version = "0.1", path = "../lib" }
 clap = "3.2"
 libc = "0.2.92"
 tokio = { version = "1", features = ["macros"] }

contrib/packaging/bootc.spec

@@ -0,0 +1,53 @@
+%bcond_without check
+
+Name:           bootc
+Version:        0.1
+Release:        1%{?dist}
+Summary:        Boot containers
+
+License:        ASL 2.0
+URL:            https://github.com/containers/bootc
+Source0:        https://github.com/containers/bootc/releases/download/v%{version}/bootc-%{version}.tar.zstd
+Source1:        https://github.com/containers/bootc/releases/download/v%{version}/bootc-%{version}-vendor.tar.zstd
+
+BuildRequires: make
+BuildRequires: openssl-devel
+BuildRequires: cargo
+BuildRequires: systemd
+# For autosetup -Sgit
+BuildRequires: git
+BuildRequires: zlib-devel
+BuildRequires: ostree-devel
+BuildRequires: openssl-devel
+BuildRequires: systemd-devel
+
+%description
+%{summary}
+
+%files
+%license LICENSE-APACHE LICENSE-MIT
+%doc README.md
+%{_bindir}/bootc
+
+%prep
+%autosetup -p1 -Sgit
+tar -xv -f %{SOURCE1}
+mkdir -p .cargo
+cat >>.cargo/config.toml << EOF
+[source.crates-io]
+replace-with = "vendored-sources"
+
+[source.vendored-sources]
+directory = "vendor"
+EOF
+
+%build
+make
+
+%install
+%make_install INSTALL="install -p -c"
+
+%changelog
+* Tue Oct 18 2022 Colin Walters <walters@verbum.org>
+- Dummy changelog
+

xtask/Cargo.toml

@@ -0,0 +1,19 @@
+# See https://github.com/matklad/cargo-xtask
+# This is an implementation detail of bootc
+[package]
+name = "xtask"
+version = "0.1.0"
+license = "MIT OR Apache-2.0"
+edition = "2021"
+publish = false
+
+[[bin]]
+name = "xtask"
+path = "src/xtask.rs"
+
+[dependencies]
+anyhow = "1.0.68"
+camino = "1.0"
+fn-error-context = "0.2.0"
+tempfile = "3.3"
+xshell = { version = "0.2" }

xtask/src/xtask.rs

@@ -0,0 +1,176 @@
+use std::fs::File;
+use std::io::{BufRead, BufReader, BufWriter, Write};
+use std::process::{Command, Stdio};
+
+use anyhow::{Context, Result};
+use camino::{Utf8Path, Utf8PathBuf};
+use fn_error_context::context;
+use xshell::{cmd, Shell};
+
+const NAME: &str = "bootc";
+const VENDORPATH: &str = "target/vendor.tar.zstd";
+
+fn main() {
+    if let Err(e) = try_main() {
+        eprintln!("{e:?}");
+        std::process::exit(1);
+    }
+}
+
+fn try_main() -> Result<()> {
+    let task = std::env::args().nth(1);
+    let sh = xshell::Shell::new()?;
+    if let Some(cmd) = task.as_deref() {
+        let f = match cmd {
+            "vendor" => vendor,
+            "package" => package,
+            "package-srpm" => package_srpm,
+            _ => print_help,
+        };
+        f(&sh)?;
+    } else {
+        print_help(&sh)?;
+    }
+    Ok(())
+}
+
+fn vendor(sh: &Shell) -> Result<()> {
+    let target = VENDORPATH;
+    cmd!(
+        sh,
+        "cargo vendor-filterer --prefix=vendor --format=tar.zstd {target}"
+    )
+    .run()?;
+    Ok(())
+}
+
+fn gitrev_to_version(v: &str) -> String {
+    let v = v.trim().trim_start_matches('v');
+    v.replace('-', ".")
+}
+
+#[context("Finding gitrev")]
+fn gitrev(sh: &Shell) -> Result<String> {
+    if let Ok(rev) = cmd!(sh, "git describe --tags").ignore_stderr().read() {
+        Ok(gitrev_to_version(&rev))
+    } else {
+        let mut desc = cmd!(sh, "git describe --tags --always").read()?;
+        desc.insert_str(0, "0.");
+        Ok(desc)
+    }
+}
+
+struct Package {
+    version: String,
+    srcpath: Utf8PathBuf,
+}
+
+#[context("Packaging")]
+fn impl_package(sh: &Shell) -> Result<Package> {
+    let v = gitrev(sh)?;
+    let namev = format!("{NAME}-{v}");
+    let p = Utf8Path::new("target").join(format!("{namev}.tar.zstd"));
+    let o = File::create(&p)?;
+    let prefix = format!("{namev}/");
+    let st = Command::new("git")
+        .args([
+            "archive",
+            "--format=tar",
+            "--prefix",
+            prefix.as_str(),
+            "HEAD",
+        ])
+        .stdout(Stdio::from(o))
+        .status()?;
+    if !st.success() {
+        anyhow::bail!("Failed to run {st:?}");
+    }
+    Ok(Package {
+        version: v,
+        srcpath: p,
+    })
+}
+
+fn package(sh: &Shell) -> Result<()> {
+    let p = impl_package(sh)?.srcpath;
+    println!("Generated: {p}");
+    Ok(())
+}
+
+fn impl_srpm(sh: &Shell) -> Result<Utf8PathBuf> {
+    let pkg = impl_package(sh)?;
+    vendor(sh)?;
+    let td = tempfile::tempdir_in("target").context("Allocating tmpdir")?;
+    let td = td.into_path();
+    let td: &Utf8Path = td.as_path().try_into().unwrap();
+    let srcpath = td.join(pkg.srcpath.file_name().unwrap());
+    std::fs::rename(pkg.srcpath, srcpath)?;
+    let v = pkg.version;
+    let vendorpath = td.join(format!("{NAME}-{v}-vendor.tar.zstd"));
+    std::fs::rename(VENDORPATH, vendorpath)?;
+    {
+        let specin = File::open(format!("contrib/packaging/{NAME}.spec"))
+            .map(BufReader::new)
+            .context("Opening spec")?;
+        let mut o = File::create(td.join(format!("{NAME}.spec"))).map(BufWriter::new)?;
+        for line in specin.lines() {
+            let line = line?;
+            if line.starts_with("Version:") {
+                writeln!(o, "# Replaced by cargo xtask package-srpm")?;
+                writeln!(o, "Version: {v}")?;
+            } else {
+                writeln!(o, "{}", line)?;
+            }
+        }
+    }
+    let d = sh.push_dir(td);
+    let mut cmd = cmd!(sh, "rpmbuild");
+    for k in [
+        "_sourcedir",
+        "_specdir",
+        "_builddir",
+        "_srcrpmdir",
+        "_rpmdir",
+    ] {
+        cmd = cmd.arg("--define");
+        cmd = cmd.arg(format!("{k} {td}"));
+    }
+    cmd.arg("--define")
+        .arg(format!("_buildrootdir {td}/.build"))
+        .args(["-bs", "bootc.spec"])
+        .run()?;
+    drop(d);
+    let mut srpm = None;
+    for e in std::fs::read_dir(td)? {
+        let e = e?;
+        let n = e.file_name();
+        let n = if let Some(n) = n.to_str() {
+            n
+        } else {
+            continue;
+        };
+        if n.ends_with(".src.rpm") {
+            srpm = Some(td.join(n));
+            break;
+        }
+    }
+    let srpm = srpm.ok_or_else(|| anyhow::anyhow!("Failed to find generated .src.rpm"))?;
+    let dest = Utf8Path::new("target").join(srpm.file_name().unwrap());
+    std::fs::rename(&srpm, &dest)?;
+    Ok(dest)
+}
+
+fn package_srpm(sh: &Shell) -> Result<()> {
+    let srpm = impl_srpm(sh)?;
+    println!("Generated: {srpm}");
+    Ok(())
+}
+
+fn print_help(_sh: &Shell) -> Result<()> {
+    eprintln!(
+        "Tasks:
+  - vendor
+"
+    );
+    Ok(())
+}