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use crate::docker::{DockerRemoveImageCommand, DockerRemoveVolumeCommand};
use crate::pack::PackBuildCommand;
use crate::util::CommandError;
use crate::{BuildConfig, BuildpackReference, PackResult, TestContext, app, build, util};
use std::borrow::Borrow;
use std::env;
use std::path::PathBuf;
use tempfile::tempdir;
/// Runner for libcnb integration tests.
///
/// # Example
/// ```no_run
/// use libcnb_test::{assert_contains, assert_empty, BuildConfig, TestRunner};
///
/// TestRunner::default().build(
/// BuildConfig::new("heroku/builder:22", "tests/fixtures/app"),
/// |context| {
/// assert_empty!(context.pack_stderr);
/// assert_contains!(context.pack_stdout, "Expected build output");
/// },
/// )
/// ```
#[derive(Default)]
pub struct TestRunner {}
impl TestRunner {
/// Starts a new integration test build.
///
/// This function copies the application to a temporary directory (if necessary), cross-compiles the current
/// crate, packages it as a buildpack and then invokes [pack](https://buildpacks.io/docs/tools/pack/)
/// to build a new Docker image with the buildpacks specified by the passed [`BuildConfig`].
///
/// After the passed test function has returned, the Docker image and volumes created by Pack are removed.
///
/// Since this function is supposed to only be used in integration tests, failures are not
/// signalled via [`Result`] values. Instead, this function panics whenever an unexpected error
/// occurred to simplify testing code.
///
/// # Example
/// ```no_run
/// use libcnb_test::{assert_contains, assert_empty, BuildConfig, TestRunner};
///
/// TestRunner::default().build(
/// BuildConfig::new("heroku/builder:22", "tests/fixtures/app"),
/// |context| {
/// assert_empty!(context.pack_stderr);
/// assert_contains!(context.pack_stdout, "Expected build output");
/// },
/// )
/// ```
pub fn build<C: Borrow<BuildConfig>, F: FnOnce(TestContext)>(&self, config: C, f: F) {
let image_name = util::random_docker_identifier();
let docker_resources = TemporaryDockerResources {
build_cache_volume_name: format!("{image_name}.build-cache"),
launch_cache_volume_name: format!("{image_name}.launch-cache"),
image_name,
};
self.build_internal(docker_resources, config, f);
}
pub(crate) fn build_internal<C: Borrow<BuildConfig>, F: FnOnce(TestContext)>(
&self,
docker_resources: TemporaryDockerResources,
config: C,
f: F,
) {
let config = config.borrow();
let cargo_manifest_dir = env::var("CARGO_MANIFEST_DIR").map_or_else(
|error| panic!("Error determining Cargo manifest directory: {error}"),
PathBuf::from,
);
let app_dir = {
let normalized_app_dir_path = if config.app_dir.is_relative() {
cargo_manifest_dir.join(&config.app_dir)
} else {
config.app_dir.clone()
};
assert!(
normalized_app_dir_path.is_dir(),
"App dir is not a valid directory: {}",
normalized_app_dir_path.display()
);
// Copy the app to a temporary directory if an app_dir_preprocessor is specified and run the
// preprocessor. Skip app copying if no changes to the app will be made.
if let Some(app_dir_preprocessor) = &config.app_dir_preprocessor {
let temporary_app_dir = app::copy_app(&normalized_app_dir_path)
.expect("Error copying app fixture to temporary location");
(app_dir_preprocessor)(temporary_app_dir.as_path().to_owned());
temporary_app_dir
} else {
normalized_app_dir_path.into()
}
};
let buildpacks_target_dir =
tempdir().expect("Error creating temporary directory for compiled buildpacks");
let mut pack_command = PackBuildCommand::new(
&config.builder_name,
&app_dir,
&docker_resources.image_name,
&docker_resources.build_cache_volume_name,
&docker_resources.launch_cache_volume_name,
);
config.env.iter().for_each(|(key, value)| {
pack_command.env(key, value);
});
for buildpack in &config.buildpacks {
match buildpack {
BuildpackReference::CurrentCrate => {
let crate_buildpack_dir = build::package_crate_buildpack(
config.cargo_profile,
&config.target_triple,
&cargo_manifest_dir,
buildpacks_target_dir.path(),
)
.unwrap_or_else(|error| {
panic!("Error packaging current crate as buildpack: {error}")
});
pack_command.buildpack(crate_buildpack_dir);
}
BuildpackReference::WorkspaceBuildpack(buildpack_id) => {
let buildpack_dir = build::package_buildpack(
buildpack_id,
config.cargo_profile,
&config.target_triple,
&cargo_manifest_dir,
buildpacks_target_dir.path(),
)
.unwrap_or_else(|error| {
panic!("Error packaging buildpack '{buildpack_id}': {error}")
});
pack_command.buildpack(buildpack_dir);
}
BuildpackReference::Other(id) => {
pack_command.buildpack(id.clone());
}
}
}
let pack_result = util::run_command(pack_command);
let output = match (&config.expected_pack_result, pack_result) {
(PackResult::Success, Ok(output)) => output,
(PackResult::Failure, Err(CommandError::NonZeroExitCode { log_output, .. })) => {
log_output
}
(PackResult::Failure, Ok(log_output)) => {
panic!("The pack build was expected to fail, but did not:\n\n{log_output}");
}
(_, Err(command_err)) => {
panic!("Error performing pack build:\n\n{command_err}");
}
};
let test_context = TestContext {
pack_stdout: output.stdout,
pack_stderr: output.stderr,
docker_resources,
config: config.clone(),
runner: self,
};
f(test_context);
}
}
#[allow(clippy::struct_field_names)]
pub(crate) struct TemporaryDockerResources {
pub(crate) build_cache_volume_name: String,
pub(crate) image_name: String,
pub(crate) launch_cache_volume_name: String,
}
impl Drop for TemporaryDockerResources {
fn drop(&mut self) {
// Ignoring errors here since we don't want to panic inside Drop.
// We don't emit a warning to stderr since that gets too noisy in some common
// cases (such as running a test suite when Docker isn't started) where the tests
// themselves will also report the same error message.
let _ = util::run_command(DockerRemoveImageCommand::new(&self.image_name));
let _ = util::run_command(DockerRemoveVolumeCommand::new([
&self.build_cache_volume_name,
&self.launch_cache_volume_name,
]));
}
}