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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:47:55 +0000 |
commit | 2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4 (patch) | |
tree | 033cc839730fda84ff08db877037977be94e5e3a /crates/cargo-test-support/src/containers.rs | |
parent | Initial commit. (diff) | |
download | cargo-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.rs | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/crates/cargo-test-support/src/containers.rs b/crates/cargo-test-support/src/containers.rs new file mode 100644 index 0000000..17040d8 --- /dev/null +++ b/crates/cargo-test-support/src/containers.rs @@ -0,0 +1,285 @@ +//! 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 + } +} |