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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:47:55 +0000
commit2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4 (patch)
tree033cc839730fda84ff08db877037977be94e5e3a /crates/cargo-test-support/src/containers.rs
parentInitial commit. (diff)
downloadcargo-2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4.tar.xz
cargo-2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4.zip
Adding upstream version 0.70.1+ds1.upstream/0.70.1+ds1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'crates/cargo-test-support/src/containers.rs')
-rw-r--r--crates/cargo-test-support/src/containers.rs285
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diff --git a/crates/cargo-test-support/src/containers.rs b/crates/cargo-test-support/src/containers.rs
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+//! Support for testing using Docker containers.
+//!
+//! The [`Container`] type is a builder for configuring a container to run.
+//! After you call `launch`, you can use the [`ContainerHandle`] to interact
+//! with the running container.
+//!
+//! Tests using containers must use `#[cargo_test(container_test)]` to disable
+//! them unless the CARGO_CONTAINER_TESTS environment variable is set.
+
+use cargo_util::ProcessBuilder;
+use std::collections::HashMap;
+use std::io::Read;
+use std::path::PathBuf;
+use std::process::Command;
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::Mutex;
+use tar::Header;
+
+/// A builder for configuring a container to run.
+pub struct Container {
+ /// The host directory that forms the basis of the Docker image.
+ build_context: PathBuf,
+ /// Files to copy over to the image.
+ files: Vec<MkFile>,
+}
+
+/// A handle to a running container.
+///
+/// You can use this to interact with the container.
+pub struct ContainerHandle {
+ /// The name of the container.
+ name: String,
+ /// The IP address of the container.
+ ///
+ /// NOTE: This is currently unused, but may be useful so I left it in.
+ /// This can only be used on Linux. macOS and Windows docker doesn't allow
+ /// direct connection to the container.
+ pub ip_address: String,
+ /// Port mappings of container_port to host_port for ports exposed via EXPOSE.
+ pub port_mappings: HashMap<u16, u16>,
+}
+
+impl Container {
+ pub fn new(context_dir: &str) -> Container {
+ assert!(std::env::var_os("CARGO_CONTAINER_TESTS").is_some());
+ let mut build_context = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
+ build_context.push("containers");
+ build_context.push(context_dir);
+ Container {
+ build_context,
+ files: Vec::new(),
+ }
+ }
+
+ /// Adds a file to be copied into the container.
+ pub fn file(mut self, file: MkFile) -> Self {
+ self.files.push(file);
+ self
+ }
+
+ /// Starts the container.
+ pub fn launch(mut self) -> ContainerHandle {
+ static NEXT_ID: AtomicUsize = AtomicUsize::new(0);
+
+ let id = NEXT_ID.fetch_add(1, Ordering::SeqCst);
+ let name = format!("cargo_test_{id}");
+ remove_if_exists(&name);
+ self.create_container(&name);
+ self.copy_files(&name);
+ self.start_container(&name);
+ let info = self.container_inspect(&name);
+ let ip_address = if cfg!(target_os = "linux") {
+ info[0]["NetworkSettings"]["IPAddress"]
+ .as_str()
+ .unwrap()
+ .to_string()
+ } else {
+ // macOS and Windows can't make direct connections to the
+ // container. It only works through exposed ports or mapped ports.
+ "127.0.0.1".to_string()
+ };
+ let port_mappings = self.port_mappings(&info);
+ self.wait_till_ready(&port_mappings);
+
+ ContainerHandle {
+ name,
+ ip_address,
+ port_mappings,
+ }
+ }
+
+ fn create_container(&self, name: &str) {
+ static BUILD_LOCK: Mutex<()> = Mutex::new(());
+
+ let image_base = self.build_context.file_name().unwrap();
+ let image_name = format!("cargo-test-{}", image_base.to_str().unwrap());
+ let _lock = BUILD_LOCK.lock().unwrap();
+ ProcessBuilder::new("docker")
+ .args(&["build", "--tag", image_name.as_str()])
+ .arg(&self.build_context)
+ .exec_with_output()
+ .unwrap();
+
+ ProcessBuilder::new("docker")
+ .args(&[
+ "container",
+ "create",
+ "--publish-all",
+ "--rm",
+ "--name",
+ name,
+ ])
+ .arg(image_name)
+ .exec_with_output()
+ .unwrap();
+ }
+
+ fn copy_files(&mut self, name: &str) {
+ if self.files.is_empty() {
+ return;
+ }
+ let mut ar = tar::Builder::new(Vec::new());
+ let files = std::mem::replace(&mut self.files, Vec::new());
+ for mut file in files {
+ ar.append_data(&mut file.header, &file.path, file.contents.as_slice())
+ .unwrap();
+ }
+ let ar = ar.into_inner().unwrap();
+ ProcessBuilder::new("docker")
+ .args(&["cp", "-"])
+ .arg(format!("{name}:/"))
+ .stdin(ar)
+ .exec_with_output()
+ .unwrap();
+ }
+
+ fn start_container(&self, name: &str) {
+ ProcessBuilder::new("docker")
+ .args(&["container", "start"])
+ .arg(name)
+ .exec_with_output()
+ .unwrap();
+ }
+
+ fn container_inspect(&self, name: &str) -> serde_json::Value {
+ let output = ProcessBuilder::new("docker")
+ .args(&["inspect", name])
+ .exec_with_output()
+ .unwrap();
+ serde_json::from_slice(&output.stdout).unwrap()
+ }
+
+ /// Returns the mapping of container_port->host_port for ports that were
+ /// exposed with EXPOSE.
+ fn port_mappings(&self, info: &serde_json::Value) -> HashMap<u16, u16> {
+ info[0]["NetworkSettings"]["Ports"]
+ .as_object()
+ .unwrap()
+ .iter()
+ .map(|(key, value)| {
+ let key = key
+ .strip_suffix("/tcp")
+ .expect("expected TCP only ports")
+ .parse()
+ .unwrap();
+ let values = value.as_array().unwrap();
+ let value = values
+ .iter()
+ .find(|value| value["HostIp"].as_str().unwrap() == "0.0.0.0")
+ .expect("expected localhost IP");
+ let host_port = value["HostPort"].as_str().unwrap().parse().unwrap();
+ (key, host_port)
+ })
+ .collect()
+ }
+
+ fn wait_till_ready(&self, port_mappings: &HashMap<u16, u16>) {
+ for port in port_mappings.values() {
+ let mut ok = false;
+ for _ in 0..30 {
+ match std::net::TcpStream::connect(format!("127.0.0.1:{port}")) {
+ Ok(_) => {
+ ok = true;
+ break;
+ }
+ Err(e) => {
+ if e.kind() != std::io::ErrorKind::ConnectionRefused {
+ panic!("unexpected localhost connection error: {e:?}");
+ }
+ std::thread::sleep(std::time::Duration::new(1, 0));
+ }
+ }
+ }
+ if !ok {
+ panic!("no listener on localhost port {port}");
+ }
+ }
+ }
+}
+
+impl ContainerHandle {
+ /// Executes a program inside a running container.
+ pub fn exec(&self, args: &[&str]) -> std::process::Output {
+ ProcessBuilder::new("docker")
+ .args(&["container", "exec", &self.name])
+ .args(args)
+ .exec_with_output()
+ .unwrap()
+ }
+
+ /// Returns the contents of a file inside the container.
+ pub fn read_file(&self, path: &str) -> String {
+ let output = ProcessBuilder::new("docker")
+ .args(&["cp", &format!("{}:{}", self.name, path), "-"])
+ .exec_with_output()
+ .unwrap();
+ let mut ar = tar::Archive::new(output.stdout.as_slice());
+ let mut entry = ar.entries().unwrap().next().unwrap().unwrap();
+ let mut contents = String::new();
+ entry.read_to_string(&mut contents).unwrap();
+ contents
+ }
+}
+
+impl Drop for ContainerHandle {
+ fn drop(&mut self) {
+ // To help with debugging, this will keep the container alive.
+ if std::env::var_os("CARGO_CONTAINER_TEST_KEEP").is_some() {
+ return;
+ }
+ remove_if_exists(&self.name);
+ }
+}
+
+fn remove_if_exists(name: &str) {
+ if let Err(e) = Command::new("docker")
+ .args(&["container", "rm", "--force", name])
+ .output()
+ {
+ panic!("failed to run docker: {e}");
+ }
+}
+
+/// Builder for configuring a file to copy into a container.
+pub struct MkFile {
+ path: String,
+ contents: Vec<u8>,
+ header: Header,
+}
+
+impl MkFile {
+ /// Defines a file to add to the container.
+ ///
+ /// This should be passed to `Container::file`.
+ ///
+ /// The path is the path inside the container to create the file.
+ pub fn path(path: &str) -> MkFile {
+ MkFile {
+ path: path.to_string(),
+ contents: Vec::new(),
+ header: Header::new_gnu(),
+ }
+ }
+
+ pub fn contents(mut self, contents: impl Into<Vec<u8>>) -> Self {
+ self.contents = contents.into();
+ self.header.set_size(self.contents.len() as u64);
+ self
+ }
+
+ pub fn mode(mut self, mode: u32) -> Self {
+ self.header.set_mode(mode);
+ self
+ }
+
+ pub fn uid(mut self, uid: u64) -> Self {
+ self.header.set_uid(uid);
+ self
+ }
+
+ pub fn gid(mut self, gid: u64) -> Self {
+ self.header.set_gid(gid);
+ self
+ }
+}