Support local buildpacks and meta-buildpacks in libcnb-test

.gitignore

@@ -5,3 +5,4 @@
 Cargo.lock
 **/fixtures/*/target/
 **/fixtures/*/packaged/
+**/test-fixtures/buildpacks/*/target/

libcnb-test/Cargo.toml

@@ -12,9 +12,9 @@ readme = "README.md"
 include = ["src/**/*", "LICENSE", "README.md"]
 
 [dependencies]
-cargo_metadata = "0.17.0"
 fastrand = "2.0.0"
 fs_extra = "1.3.0"
+libcnb-common.workspace = true
 libcnb-data.workspace = true
 libcnb-package.workspace = true
 tempfile = "3.7.1"

libcnb-test/src/build.rs

@@ -1,62 +1,138 @@
-use cargo_metadata::MetadataCommand;
-use libcnb_package::build::{build_buildpack_binaries, BuildBinariesError};
+use libcnb_common::toml_file::{read_toml_file, TomlFileError};
+use libcnb_data::buildpack::{BuildpackDescriptor, BuildpackId};
+use libcnb_package::buildpack_dependency_graph::{
+    build_libcnb_buildpacks_dependency_graph, BuildBuildpackDependencyGraphError,
+};
 use libcnb_package::cross_compile::{cross_compile_assistance, CrossCompileAssistance};
-use libcnb_package::{assemble_buildpack_directory, CargoProfile};
+use libcnb_package::dependency_graph::{get_dependencies, GetDependenciesError};
+use libcnb_package::output::create_packaged_buildpack_dir_resolver;
+use libcnb_package::package::PackageBuildpackError;
+use libcnb_package::{find_cargo_workspace_root_dir, CargoProfile, FindCargoWorkspaceRootError};
+use std::collections::BTreeMap;
+use std::fs;
 use std::path::PathBuf;
 use tempfile::{tempdir, TempDir};
 
 /// Packages the current crate as a buildpack into a temporary directory.
 pub(crate) fn package_crate_buildpack(
     cargo_profile: CargoProfile,
     target_triple: impl AsRef<str>,
-) -> Result<TempDir, PackageCrateBuildpackError> {
+) -> Result<PackagedBuildpackDir, PackageTestBuildpackError> {
     let cargo_manifest_dir = std::env::var("CARGO_MANIFEST_DIR")
         .map(PathBuf::from)
-        .map_err(PackageCrateBuildpackError::CannotDetermineCrateDirectory)?;
+        .map_err(PackageTestBuildpackError::CannotDetermineCrateDirectory)?;
 
-    let cargo_metadata = MetadataCommand::new()
-        .manifest_path(&cargo_manifest_dir.join("Cargo.toml"))
-        .exec()
-        .map_err(PackageCrateBuildpackError::CargoMetadataError)?;
+    let buildpack_toml = cargo_manifest_dir.join("buildpack.toml");
 
-    let cargo_env = match cross_compile_assistance(target_triple.as_ref()) {
+    assert!(
+        buildpack_toml.exists(),
+        "Could not package directory as buildpack! No `buildpack.toml` file exists at {}",
+        cargo_manifest_dir.display()
+    );
+
+    let buildpack_descriptor: BuildpackDescriptor =
+        read_toml_file(buildpack_toml).map_err(PackageTestBuildpackError::CannotReadBuildpack)?;
+
+    package_buildpack(
+        &buildpack_descriptor.buildpack().id,
+        cargo_profile,
+        target_triple,
+    )
+}
+
+pub(crate) fn package_buildpack(
+    buildpack_id: &BuildpackId,
+    cargo_profile: CargoProfile,
+    target_triple: impl AsRef<str>,
+) -> Result<PackagedBuildpackDir, PackageTestBuildpackError> {
+    let cargo_manifest_dir = std::env::var("CARGO_MANIFEST_DIR")
+        .map(PathBuf::from)
+        .map_err(PackageTestBuildpackError::CannotDetermineCrateDirectory)?;
+
+    let cargo_build_env = match cross_compile_assistance(target_triple.as_ref()) {
         CrossCompileAssistance::HelpText(help_text) => {
-            return Err(PackageCrateBuildpackError::CrossCompileConfigurationError(
+            return Err(PackageTestBuildpackError::CrossCompileConfigurationError(
                 help_text,
             ));
         }
         CrossCompileAssistance::NoAssistance => Vec::new(),
         CrossCompileAssistance::Configuration { cargo_env } => cargo_env,
     };
 
-    let buildpack_dir =
-        tempdir().map_err(PackageCrateBuildpackError::CannotCreateBuildpackTempDirectory)?;
+    let workspace_root_path = find_cargo_workspace_root_dir(&cargo_manifest_dir)
+        .map_err(PackageTestBuildpackError::FindCargoWorkspace)?;
 
-    let buildpack_binaries = build_buildpack_binaries(
-        &cargo_manifest_dir,
-        &cargo_metadata,
+    let package_dir =
+        tempdir().map_err(PackageTestBuildpackError::CannotCreateBuildpackTempDirectory)?;
+
+    let buildpack_dir_resolver = create_packaged_buildpack_dir_resolver(
+        package_dir.as_ref(),
         cargo_profile,
-        &cargo_env,
         target_triple.as_ref(),
-    )
-    .map_err(PackageCrateBuildpackError::BuildBinariesError)?;
+    );
+
+    // TODO: this could accidentally detect a packaged meta-buildpack twice. how should we ignore directories
+    //       containing packaged buildpacks that might get detected now that the user controls --package-dir?
+    //       - support .gitignore or some other persistent configuration?
+    //       - during packaging should we create some type of file that indicates the output is a packaged buildpack?
+    let buildpack_dependency_graph =
+        build_libcnb_buildpacks_dependency_graph(&workspace_root_path, &[])
+            .map_err(PackageTestBuildpackError::CreateBuildpackDependencyGraph)?;
 
-    assemble_buildpack_directory(
-        buildpack_dir.path(),
-        cargo_manifest_dir.join("buildpack.toml"),
-        &buildpack_binaries,
+    let root_node = buildpack_dependency_graph
+        .node_weights()
+        .find(|node| node.buildpack_id == buildpack_id.clone());
+
+    assert!(
+        root_node.is_some(),
+        "Could not package directory as buildpack! No buildpack with id `{buildpack_id}` exists in the workspace at {}",
+        workspace_root_path.display()
+    );
+
+    let build_order = get_dependencies(
+        &buildpack_dependency_graph,
+        &[root_node.expect("The root node should exist")],
     )
-    .map_err(PackageCrateBuildpackError::CannotAssembleBuildpackDirectory)?;
+    .map_err(PackageTestBuildpackError::GetDependencies)?;
+
+    let mut packaged_buildpack_dirs = BTreeMap::new();
+    for node in &build_order {
+        let buildpack_destination_dir = buildpack_dir_resolver(&node.buildpack_id);
+
+        fs::create_dir_all(&buildpack_destination_dir).unwrap();
+
+        libcnb_package::package::package_buildpack(
+            &node.path,
+            cargo_profile,
+            target_triple.as_ref(),
+            &cargo_build_env,
+            &buildpack_destination_dir,
+            &packaged_buildpack_dirs,
+        )
+        .map_err(PackageTestBuildpackError::PackageBuildpack)?;
+
+        packaged_buildpack_dirs.insert(node.buildpack_id.clone(), buildpack_destination_dir);
+    }
+
+    Ok(PackagedBuildpackDir {
+        _root: package_dir,
+        path: buildpack_dir_resolver(buildpack_id),
+    })
+}
 
-    Ok(buildpack_dir)
+pub(crate) struct PackagedBuildpackDir {
+    _root: TempDir,
+    pub(crate) path: PathBuf,
 }
 
 #[derive(Debug)]
-pub(crate) enum PackageCrateBuildpackError {
-    BuildBinariesError(BuildBinariesError),
-    CannotAssembleBuildpackDirectory(std::io::Error),
+pub(crate) enum PackageTestBuildpackError {
     CannotCreateBuildpackTempDirectory(std::io::Error),
     CannotDetermineCrateDirectory(std::env::VarError),
-    CargoMetadataError(cargo_metadata::Error),
+    CannotReadBuildpack(TomlFileError),
+    CreateBuildpackDependencyGraph(BuildBuildpackDependencyGraphError),
     CrossCompileConfigurationError(String),
+    FindCargoWorkspace(FindCargoWorkspaceRootError),
+    GetDependencies(GetDependenciesError<BuildpackId>),
+    PackageBuildpack(PackageBuildpackError),
 }

libcnb-test/src/build_config.rs

@@ -1,3 +1,4 @@
+use libcnb_data::buildpack::BuildpackId;
 use std::collections::HashMap;
 use std::path::{Path, PathBuf};
 use std::rc::Rc;
@@ -251,6 +252,8 @@ impl BuildConfig {
 pub enum BuildpackReference {
     /// References the buildpack in the Rust Crate currently being tested.
     Crate,
+    /// References a libcnb.rs buildpack within the Rust Workspace that needs to be packaged into a buildpack
+    LibCnbRs(BuildpackId),
     /// References another buildpack by id, local directory or tarball.
     Other(String),
 }

libcnb-test/src/pack.rs

@@ -162,6 +162,17 @@ impl From<PackSbomDownloadCommand> for Command {
     }
 }
 
+#[derive(Clone, Debug)]
+pub(crate) struct PackVersionCommand;
+
+impl From<PackVersionCommand> for Command {
+    fn from(_: PackVersionCommand) -> Self {
+        let mut command = Self::new("pack");
+        command.arg("--version");
+        command
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

libcnb-test/src/test_runner.rs

@@ -1,5 +1,5 @@
 use crate::docker::DockerRemoveImageCommand;
-use crate::pack::PackBuildCommand;
+use crate::pack::{PackBuildCommand, PackVersionCommand};
 use crate::util::CommandError;
 use crate::{app, build, util, BuildConfig, BuildpackReference, PackResult, TestContext};
 use std::borrow::Borrow;
@@ -56,6 +56,8 @@ impl TestRunner {
         config: C,
         f: F,
     ) {
+        check_required_pack_version();
+
         let config = config.borrow();
 
         let app_dir = {
@@ -88,14 +90,7 @@ impl TestRunner {
             }
         };
 
-        let temp_crate_buildpack_dir =
-            config
-                .buildpacks
-                .contains(&BuildpackReference::Crate)
-                .then(|| {
-                    build::package_crate_buildpack(config.cargo_profile, &config.target_triple)
-                        .expect("Could not package current crate as buildpack")
-                });
+        let mut buildpack_dirs = vec![];
 
         let mut pack_command = PackBuildCommand::new(&config.builder_name, &app_dir, &image_name);
 
@@ -106,10 +101,22 @@ impl TestRunner {
         for buildpack in &config.buildpacks {
             match buildpack {
                 BuildpackReference::Crate => {
-                    pack_command.buildpack(temp_crate_buildpack_dir.as_ref()
-                        .expect("Test references crate buildpack, but crate wasn't packaged as a buildpack. This is an internal libcnb-test error, please report any occurrences."))
+                    let crate_buildpack_dir = build::package_crate_buildpack(config.cargo_profile, &config.target_triple)
+                        .expect("Test references crate buildpack, but crate wasn't packaged as a buildpack. This is an internal libcnb-test error, please report any occurrences");
+                    pack_command.buildpack(crate_buildpack_dir.path.clone());
+                    buildpack_dirs.push(crate_buildpack_dir);
+                }
+
+                BuildpackReference::LibCnbRs(builpack_id) => {
+                    let buildpack_dir = build::package_buildpack(builpack_id, config.cargo_profile, &config.target_triple)
+                        .unwrap_or_else(|_| panic!("Test references buildpack `{builpack_id}`, but this directory wasn't packaged as a buildpack. This is an internal libcnb-test error, please report any occurrences"));
+                    pack_command.buildpack(buildpack_dir.path.clone());
+                    buildpack_dirs.push(buildpack_dir);
+                }
+
+                BuildpackReference::Other(id) => {
+                    pack_command.buildpack(id.clone());
                 }
-                BuildpackReference::Other(id) => pack_command.buildpack(id.clone()),
             };
         }
 
@@ -146,3 +153,33 @@ impl TestRunner {
         f(test_context);
     }
 }
+
+fn check_required_pack_version() {
+    match util::run_command(PackVersionCommand) {
+        Ok(output) => {
+            let version = output.stdout.trim();
+            let mut split = version.split('.');
+            let major: u32 = split
+                .next()
+                .map(|value| {
+                    value
+                        .parse::<u32>()
+                        .expect("Major coordinate should be a number")
+                })
+                .expect("Major coordinate should be present in pack --version output");
+            let minor: u32 = split
+                .next()
+                .map(|value| {
+                    value
+                        .parse::<u32>()
+                        .expect("Minor coordinate should be a number")
+                })
+                .expect("Minor coordinate should be present in pack --version output");
+            let is_min_version = major == 0 && minor >= 30 || major >= 1;
+            assert!(is_min_version, "Pack version 0.30+ is required but {version} is installed. Please upgrade your pack CLI.");
+        }
+        Err(error) => {
+            panic!("Error determinging pack version:\n\n{error}");
+        }
+    }
+}

libcnb-test/test-fixtures/buildpacks/libcnb-test-a/Cargo.toml

@@ -0,0 +1,5 @@
+[package]
+name = "one"
+version = "0.0.0"
+
+[workspace]

libcnb-test/test-fixtures/buildpacks/libcnb-test-a/buildpack.toml

@@ -0,0 +1,8 @@
+api = "0.8"
+
+[buildpack]
+id = "libcnb-test/a"
+version = "0.0.0"
+
+[[stacks]]
+id = "*"

libcnb-test/test-fixtures/buildpacks/libcnb-test-a/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Buildpack A");
+}

libcnb-test/test-fixtures/buildpacks/libcnb-test-b/Cargo.toml

@@ -0,0 +1,5 @@
+[package]
+name = "two"
+version = "0.0.0"
+
+[workspace]

libcnb-test/test-fixtures/buildpacks/libcnb-test-b/buildpack.toml

@@ -0,0 +1,8 @@
+api = "0.8"
+
+[buildpack]
+id = "libcnb-test/b"
+version = "0.0.0"
+
+[[stacks]]
+id = "*"

libcnb-test/test-fixtures/buildpacks/libcnb-test-b/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Buildpack B");
+}

libcnb-test/test-fixtures/buildpacks/libcnb-test-meta/buildpack.toml

@@ -0,0 +1,22 @@
+api = "0.8"
+
+[buildpack]
+id = "libcnb-test/meta"
+name = "Meta-buildpack Test"
+version = "0.0.0"
+homepage = "https://example.com"
+description = "Official test example"
+keywords = ["test"]
+
+[[buildpack.licenses]]
+type = "BSD-3-Clause"
+
+[[order]]
+
+[[order.group]]
+id = "libcnb-test/a"
+version = "0.0.0"
+
+[[order.group]]
+id = "libcnb-test/b"
+version = "0.0.0"

libcnb-test/test-fixtures/buildpacks/libcnb-test-meta/package.toml

@@ -0,0 +1,9 @@
+[buildpack]
+uri = "."
+
+[[dependencies]]
+uri = "libcnb:libcnb-test/a"
+
+[[dependencies]]
+uri = "libcnb:libcnb-test/b"
+