self_update

self_update provides updaters for updating rust executables in-place from various release distribution backends.

Supported backends: GitHub, GitLab, Gitea, Gitee, S3 (Amazon S3, Google GCS, DigitalOcean Spaces, or any S3-compatible endpoint), and Manifest (any static file server). The forge and S3 backends each expose a ReleaseList builder alongside the Update (configure -> build -> update) API; the manifest backend exposes Update only.

Quick start

use self_update::cargo_crate_version;

fn update() -> Result<(), Box<dyn std::error::Error>> {
    let status = self_update::backends::github::Update::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .bin_name("github")
        .show_download_progress(true)
        .current_version(cargo_crate_version!())
        .build()?
        .update()?;
    println!("Update status: `{}`!", status.version());
    Ok(())
}

Upgrading from 0.x? 1.0 makes a focused set of breaking changes to clean up the public API. See the 1.0 migration guide for a step-by-step walkthrough, or the agent-oriented guide for automated migration tooling.

Running unattended (daemon / CI / service)? The defaults are interactive: show_output is true and no_confirm is false, so update() prints a release-status block to stdout and then blocks on an interactive yes/no prompt waiting on stdin. With no terminal attached this stalls (or aborts). For any non-interactive caller set .no_confirm(true) to skip the prompt, and usually .show_output(false) to silence the status block. These are settings only -- the defaults are unchanged. Note the status block is printed before the confirmation prompt, so suppressing one does not suppress the other.

Usage

Features

At least one HTTP client must be selected. A build with no client -- for example default-features = false with only a TLS feature such as features = ["rustls"] -- fails to compile with no HTTP client selected - enable at least one of the reqwest (default) or ureq features. Add a client explicitly, e.g. default-features = false, features = ["ureq", "rustls", "github"]. Multiple clients and multiple TLS backends may coexist (reqwest is preferred when both are present):

• reqwest (default): use the reqwest HTTP client;
• ureq: use the ureq HTTP client, either alongside reqwest or as a drop-in replacement (set default-features = false to drop reqwest);
• rustls (default): pure-Rust TLS; does not support 32-bit macOS;
• native-tls: opt-in native/OpenSSL TLS for the selected client;
• native-tls-vendored: build OpenSSL from source and link it statically (for targets where a usable system OpenSSL is awkward, e.g. musl or some cross-compiles); implies native-tls, applies to the reqwest client;

Note that enabling a client with neither TLS feature compiles (plain-http release hosts remain reachable) but any https URL then fails at request time with a transport error; enable rustls or native-tls for https.

The following cargo features are enabled by default:

• github: the GitHub Releases backend;
• progress-bar: terminal download progress bar;

The following are opt-in; activate the one(s) your release files need:

• gitlab: the GitLab Releases backend;
• gitea: the Gitea Releases backend;
• gitee: the Gitee Releases backend;
• s3: the S3-compatible backend (Amazon S3, GCS, DigitalOcean Spaces, etc.);
• s3-auth: sign S3 requests (AWS SigV4) for private buckets; implies s3;
• manifest: the static-file manifest backend; fetches releases from a manifest.json served by any HTTP endpoint; no new dependencies;
• archive-tar: support for tar archive format;
• archive-zip: support for zip archive format;
• compression-tar-gz: support for gzip compression (.tar.gz, .tgz, plain .gz);
• compression-tar-xz: support for xz compression (.tar.xz, .txz, plain .xz); pure-Rust, no C liblzma dependency;
• compression-zip-deflate: support for zip's deflate compression format;
• compression-zip-bzip2: support for zip's bzip2 compression format;
• signatures: use zipsign to verify .zip and .tar.gz artifacts. Artifacts are assumed to have been signed using zipsign;
• checksums: verify a downloaded artifact against a SHA-256/SHA-512 checksum before installing it -- automatically against the digest github publishes per release asset, and/or against a known checksum you pass in (e.g. from a SHA256SUMS file); see Checksum verification below;
• async: add async (*_async) update methods alongside the unchanged blocking API; tokio-only, requires reqwest (ureq and reqwest can coexist -- reqwest serves the async path, and the sync API prefers reqwest when both are present); see Async below.

github is the only backend in the default feature set. The S3 backend requires the s3 feature; s3-auth implies s3. gitlab, gitea, gitee, and manifest each require their own feature.

Example

Run the following example to see self_update in action:

cargo run --example github --features "signatures archive-tar compression-tar-gz".

There are equivalent examples for the other backends (gitlab, gitea, gitee, s3), e.g.:

cargo run --example gitlab --features "gitlab archive-tar compression-tar-gz".

Amazon S3, Google GCS, and DigitalOcean Spaces, as well as any S3 compatible server are also supported through the S3 backend to check for new releases. Provided a bucket_name and asset_prefix string, self_update will look up all matching files using the following format as a convention for the filenames: [directory/]<asset name>-<semver>-<platform/target>.<extension>. Leading directories will be stripped from the file name allowing the use of subdirectories in the S3 bucket, and any file not matching the format, or not matching the provided prefix string, will be ignored.

use self_update::cargo_crate_version;

fn update() -> Result<(), Box<dyn ::std::error::Error>> {
    let status = self_update::backends::s3::Update::configure()
        // .endpoint(self_update::backends::s3::Endpoint::GCS)
        // .endpoint("https://s3.example.com")
        .bucket_name("self_update_releases")
        .asset_prefix("something/self_update")
        .region("eu-west-2")
        .bin_name("self_update_example")
        // To authenticate (requires the `s3-auth` feature), read the credentials at
        // runtime rather than baking them into the binary with `env!`:
        // .access_key((std::env::var("AWS_ACCESS_KEY_ID")?, std::env::var("AWS_SECRET_ACCESS_KEY")?))
        .show_download_progress(true)
        .current_version(cargo_crate_version!())
        .build()?
        .update()?;
    println!("S3 Update status: `{}`!", status.version());
    Ok(())
}

The manifest backend (manifest feature) serves releases from a manifest.json file hosted on any static file server. The tool author publishes the manifest at a stable URL; assets may be absolute URLs or relative paths resolved against that URL. Asset digest fields (sha256:<hex>) plug into the existing checksum verification path when the checksums feature is on. See specs/ref-manifest-backend.md for the full schema.

use self_update::cargo_crate_version;

fn update() -> Result<(), Box<dyn std::error::Error>> {
    let status = self_update::backends::manifest::Update::configure()
        .manifest_url("https://example.net/releases/manifest.json")
        .bin_name("app")
        .current_version(cargo_crate_version!())
        .build()?
        .update()?;
    println!("Manifest update status: `{}`!", status.version());
    Ok(())
}

Separate utilities are also exposed (NOTE: the following example extracts a .tar.gz, which requires both the archive-tar and compression-tar-gz features -- archive-tar reads the tar archive and compression-tar-gz decodes the gzip layer; see the features section above). It downloads, extracts, and replaces the running binary by hand; the staging directory and the in-place replacement use the tempfile and self_replace crates, which you add as your own dependencies (they are no longer re-exported from self_update):

fn update() -> Result<(), Box<dyn std::error::Error>> {
    let releases = self_update::backends::github::ReleaseList::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .build()?
        .fetch()?;
    println!("found releases:");
    println!("{:#?}\n", releases);

    // get the first available release (`fetch` returns a `Releases`; `latest()` is the first entry)
    let latest = releases.latest().unwrap();
    let asset = latest
        .asset_for(&self_update::get_target(), None)
        .unwrap();

    let tmp_dir = tempfile::Builder::new()
            .prefix("self_update")
            .tempdir_in(::std::env::current_dir()?)?;
    let tmp_tarball_path = tmp_dir.path().join(asset.name());
    let tmp_tarball = ::std::fs::File::create(&tmp_tarball_path)?;

    self_update::Download::from_url(asset.download_url())
        .request_header(self_update::http::header::ACCEPT, "application/octet-stream")
        .download_to(&tmp_tarball)?;

    let bin_name = std::path::PathBuf::from("self_update_bin");
    self_update::Extract::from_source(&tmp_tarball_path)
        .archive(self_update::ArchiveKind::Tar(Some(self_update::Compression::Gz)))
        .extract_file(&tmp_dir.path(), &bin_name)?;

    let new_exe = tmp_dir.path().join(bin_name);
    self_replace::self_replace(new_exe)?;

    Ok(())
}

Multi-file / non-executable install

The high-level update() flow replaces a single executable. To update a tool that ships more than one file (a binary plus sidecar libraries/resources), or to install files that aren't the running executable, download and extract the whole archive yourself and then install the files with MoveAll, which applies a set of (source -> dest) moves transactionally: either every move succeeds, or — on the first failure — all already-applied moves are rolled back, so a failed update can't leave a half-installed tool. Because it uses rename (which can't cross filesystems), the source files, every destination, and the temp dir must all be on the same filesystem.

NOTE: this example extracts a .tar.gz, which requires both the archive-tar and compression-tar-gz features.

fn update() -> Result<(), Box<dyn std::error::Error>> {
    let tmp_dir = tempfile::TempDir::new()?;
    let tarball_path = tmp_dir.path().join("release.tar.gz");
    // ... download the archive to `tarball_path` (see the example above) ...

    // The extracted files are renamed into place, so the staging dir (the move sources) and the
    // stash dir must be on the same filesystem as the destinations — create both next to them
    // rather than in $TMPDIR. The `/usr/local` paths below are illustrative; use destinations
    // and temp dirs you have write access to (these may require elevated privileges).
    let staging = tempfile::TempDir::new_in("/usr/local")?;
    self_update::Extract::from_source(&tarball_path)
        .archive(self_update::ArchiveKind::Tar(Some(self_update::Compression::Gz)))
        .extract_into(staging.path())?;

    // Install several files atomically (all-or-nothing).
    let stash = tempfile::TempDir::new_in("/usr/local")?;
    self_update::MoveAll::from_temp(stash.path())
        .add(staging.path().join("app"), "/usr/local/bin/app")
        .add(staging.path().join("libapp.so"), "/usr/local/lib/libapp.so")
        .commit()?;
    Ok(())
}

Checksum verification

With the checksums feature, the crate verifies the downloaded artifact against a digest before installing — a mismatch aborts the update. Two sources of digests, independently applied (when both apply, both must pass):

• Release-published digests, automatic. GitHub publishes a sha256:<hex> digest per release asset; the updater verifies the download against it whenever the selected asset carries one. This is on by default with the checksums feature — no configuration needed — and can be disabled with verify_release_digest(false). The other backends' APIs publish no digest, so the check is a no-op there (a custom ReleaseSource can supply one via ReleaseAsset::with_digest). Note this is an integrity check only — the forge recomputes the digest if an asset is replaced — so it is not a substitute for the signatures feature.
• A known digest you pass explicitly (e.g. one published in a SHA256SUMS file alongside the release) via verify_checksum. The algorithm is chosen by the Checksum variant (Sha256 / Sha512).

Both complement the signatures feature (zipsign), which verifies authenticity rather than a published digest.

fn update() -> Result<(), Box<dyn std::error::Error>> {
    self_update::backends::github::Update::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .bin_name("github")
        .current_version(self_update::cargo_crate_version!())
        // hex digest, obtained out of band (e.g. parsed from the release's SHA256SUMS)
        .verify_checksum(self_update::Checksum::Sha256("9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08".into()))
        .build()?
        .update()?;
    Ok(())
}

Checking for an update without installing

To check whether a newer release exists without downloading or installing anything, call is_update_available() on the built updater. It fetches the release listing and returns the newest strictly-newer Release (or None when up to date):

fn check() -> Result<(), Box<dyn std::error::Error>> {
    let update = self_update::backends::github::Update::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .bin_name("github")
        .current_version(self_update::cargo_crate_version!())
        .build()?;

    match update.is_update_available()? {
        Some(release) => println!("update available: {}", release.version()),
        None => println!("already up to date"),
    }
    Ok(())
}

Restarting after an update

After update() returns VersionStatus::Updated the on-disk executable has been replaced, but the running process keeps executing the old code until it exits. To relaunch into the new binary immediately, use the restart module: restart::restart() re-runs with the current arguments, and restart::restart_with(args) re-runs with a fresh argument list (e.g. to drop an --upgrade flag so the new process does not update again). On unix the process image is replaced with exec (the PID is preserved); on windows the new binary is spawned and the current process exits. See the module docs for the platform details.

Permissions

The crate never escalates privileges. There is no sudo re-exec, no polkit interaction, and no UAC prompt. Privilege escalation is always the caller's choice.

An install into an unwritable location fails with Error::InstallPathNotWritable naming the path (the configured bin_install_path). Any other IO failure at the install step surfaces as Error::Io with a message naming the install path, so the path is visible in the error regardless of the kind.

Setting check_install_path_writable(true) on the builder opts into a preflight probe that runs immediately before the download. Only a definite PermissionDenied refusal errors early; indeterminate results (a missing parent directory, an unusual filesystem) are treated as "proceed" and let the real install step surface the outcome. The default is false.

fn update() -> Result<(), Box<dyn std::error::Error>> {
    match self_update::backends::github::Update::configure()
        .repo_owner("owner")
        .repo_name("repo")
        .bin_name("app")
        .current_version(self_update::cargo_crate_version!())
        .check_install_path_writable(true)
        .build()?
        .update()
    {
        Ok(status) => println!("updated: {}", status.version()),
        Err(self_update::Error::InstallPathNotWritable { .. }) => {
            // The install path is not writable by this process. Elevation is the
            // application's choice: re-run under sudo, spawn a UAC-elevated child, etc.
            // Use the `restart` module for the exec/spawn mechanics when relaunching
            // with a modified argument list.
            eprintln!("install path not writable; re-run with elevated privileges");
        }
        Err(e) => return Err(e.into()),
    }
    Ok(())
}

Periodic update checks

Every update() / is_update_available() call makes a network request. To avoid checking on every run, gate the check behind UpdateCheckGuard, a small stamp-file guard: should_check() reports whether the configured interval has elapsed since the last recorded check, and record_check() stamps the current time. The caller owns the stamp-file path. It is a guard, not a scheduler -- no threads or timers, and no extra dependencies. See the check_interval module for the semantics.

GitHub rate limits

Requests to the GitHub REST API are rate limited by GitHub itself, not by this crate:

• Unauthenticated requests are limited to 60 per hour per source IP; authenticated requests (set any personal access token via auth_token) get 5000 per hour. A token needs no scopes to raise the limit for a public repository.
• An update check costs one API request (the latest-release lookup, or one request per page of a paginated listing). The asset download itself is a CDN redirect and does not count against the core API limit.
• When you are rate limited, GitHub responds with HTTP 403 (and an x-ratelimit-remaining: 0 header), which this crate surfaces as Error::Unauthorized { status: 403, .. } -- the same variant as a genuine auth failure, so recognize it by the symptom (a 403 that appears only under frequent checking).
• To avoid it: set an auth_token (5000/hour), and check less often -- the UpdateCheckGuard above throttles how often you check. The retry/backoff setters do not help here; retrying a rate-limited request only consumes more quota.

Listing releases (ReleaseList)

Each built-in backend exposes a ReleaseList builder for fetching the list of available releases without performing an update. There is no single unifying self_update::ReleaseList type: every backend has its own, distinct ReleaseList (the fields and request shape differ per host), so they are reached through their backend modules rather than re-exported at the crate root:

• backends::github::ReleaseList
• backends::gitlab::ReleaseList
• backends::gitea::ReleaseList
• backends::gitee::ReleaseList
• backends::s3::ReleaseList

The manifest backend has no separate ReleaseList struct. Its ManifestSource is a ReleaseSource implementation that can be used directly, or listing can be driven through the inherent verbs (get_latest_release, get_newer_releases, is_update_available) on a built manifest::Update.

The custom backend has no ReleaseList by design: listing is performed entirely by your ReleaseSource (or AsyncReleaseSource) implementation, which already returns Release values directly.

Custom backends

To update from a host the built-in backends (github, gitlab, gitea, gitee, s3, manifest) don't cover — another forge, a private artifact registry, a plain HTTP directory — implement the ReleaseSource trait and drive a full update through the backends::custom backend, which reuses the crate's compare → select-asset → download → verify → extract → install flow. Only get_releases (the fetch that says where releases come from) is required; get_latest_release / get_release_version are derived from it by default and can be overridden when the host has cheaper dedicated endpoints. You build Releases with Release::builder and ReleaseAsset::new; the ReleaseUpdate trait stays sealed.

ReleaseSource is synchronous. For a natively-async source, implement AsyncReleaseSource (the same fetches as async fn) and drive it through backends::custom::AsyncUpdate + build_async(); to reuse a Clone sync source from the async API, wrap it in backends::custom::Blocking.

use self_update::{Release, ReleaseAsset, ReleaseSource, cargo_crate_version};

struct MyHost;
impl ReleaseSource for MyHost {
    fn get_releases(&self) -> self_update::Result<Vec<Release>> {
        Ok(vec![Release::builder()
            .version("1.2.3")
            .asset(ReleaseAsset::new("app-x86_64-unknown-linux-gnu.tar.gz", "https://host/app.tar.gz"))
            .build()?])
    }
}

fn update() -> Result<(), Box<dyn std::error::Error>> {
    let status = self_update::backends::custom::Update::configure()
        .source(MyHost)
        .bin_name("app")
        .current_version(cargo_crate_version!())
        .build()?
        .update()?;
    println!("custom backend update status: `{}`!", status.version());
    Ok(())
}

Async

With the async feature, every built-in backend's Update builder gains a build_async() that returns a distinct AsyncUpdate wrapper (one per backend). Its async (*_async) verbs — update_async(), update_extended_async(), get_latest_release_async(), get_newer_releases_async(), get_release_version_async(), and is_update_available_async() — are inherent methods on that wrapper, so a tokio application can update without wrapping the blocking calls in spawn_blocking and without importing any trait. Crucially, the AsyncUpdate wrapper does not expose the blocking verbs: calling .update() on an async-built updater is a compile error, so the old footgun of accidentally running a blocking update from an async context is gone. The blocking API is unchanged; the async path is purely additive. It is tokio-only and requires reqwest -- ureq and reqwest can coexist (reqwest serves the async path, and the sync API prefers reqwest when both are present); the only invalid configuration is async without reqwest. Network IO becomes async, and the extract/replace tail runs on tokio::task::spawn_blocking so it does not block the executor.

async fn update() -> Result<(), Box<dyn std::error::Error>> {
    let status = self_update::backends::github::Update::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .bin_name("github")
        .current_version(self_update::cargo_crate_version!())
        .build_async()?
        .update_async()
        .await?;
    println!("Update status: `{}`!", status.version());
    Ok(())
}

The AsyncUpdate wrapper exposes only the *_async verbs; the blocking update() is not a method on it, so accidentally calling it from async code does not compile. The following block is compile_fail for exactly that reason — update is not a method on the async wrapper (this block is intentionally not feature-gated: gating it behind cfg(feature = "async") would make it an empty, successfully-compiling doctest in the crate's no-async test lanes, which a compile_fail block must never do):

fn wont_compile() -> Result<(), Box<dyn std::error::Error>> {
    let updater = self_update::backends::github::Update::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .bin_name("github")
        .current_version(self_update::cargo_crate_version!())
        .build_async()?;
    // `update()` is the BLOCKING verb; it is not exposed on the async `AsyncUpdate` wrapper.
    updater.update()?;
    Ok(())
}

Custom HTTP client

The .timeout() / .request_header() / .retries() builder knobs cover most transport needs, but for full control — custom TLS roots / mTLS, connection pooling, redirect policy, proxy-with-auth, or simply reusing your application's existing client — you can hand the crate a pre-built client. It is used for both the release listing and the download. The client-specific convenience setters are reqwest_client (a blocking reqwest::blocking::Client, used by the blocking API), reqwest_async_client (an async reqwest::Client, used by the *_async verbs), and ureq_agent (a ureq::Agent); each wraps your client behind the crate's object-safe HTTP transport trait. The compiled client crate(s) are re-exported (self_update::reqwest / self_update::ureq) so you don't need a separate dependency to name the type. (Since the transport is a runtime trait seam, reqwest and ureq are no longer mutually exclusive — both can be enabled, and the sync API prefers reqwest when both are present.) For test doubles or fully custom transport, inject any type that implements the object-safe trait directly via .http_client(Arc<dyn HttpClient>) (sync) or .http_client_async(Arc<dyn AsyncHttpClient>) (async); see the http_client module for the trait definitions.

When you inject a client, .request_header() still applies, and .retries() still applies to the release-listing requests and to the download's request-establishment phase (a mid-stream failure is not retried, as that would corrupt the partially-written destination), and for reqwest the per-request .timeout() is layered on too; but HTTP(S)_PROXY env and the crate's TLS feature are left entirely to your client (and a ureq::Agent owns its own timeout, so .timeout() does not apply to an injected agent — configure it on the agent). reqwest_client feeds the sync verbs and reqwest_async_client the async ones — injecting only one and calling the other half just uses the crate's per-call client for that half.

fn update() -> Result<(), Box<dyn std::error::Error>> {
    let client = self_update::reqwest::blocking::Client::builder()
        // .add_root_certificate(...) / .proxy(...) / .danger_accept_invalid_certs(...) etc.
        .build()?;
    self_update::backends::github::Update::configure()
        .repo_owner("jaemk")
        .repo_name("self_update")
        .bin_name("github")
        .current_version(self_update::cargo_crate_version!())
        .reqwest_client(client)
        .build()?
        .update()?;
    Ok(())
}

Troubleshooting

Cross-compilation (cross / cargo-cross). rustls is the default TLS backend, so no additional configuration is needed for cross-compilation: a build on default features already uses rustls. If you have explicitly switched to native-tls and want to revert, remove the native-tls feature; rustls is active by default.

TLS certificate errors on Linux (native-tls / OpenSSL). With the native-TLS backend, OpenSSL finds the system CA bundle on its own on most distributions. In a minimal environment where it can't (some containers, musl static builds, or a non-standard cert layout) a request may fail with a certificate-verification error. Point OpenSSL at the bundle by exporting SSL_CERT_FILE (and, if needed, SSL_CERT_DIR) before running your program — the paths vary by distribution, e.g. on a Debian/Ubuntu base:

export SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt
export SSL_CERT_DIR=/etc/ssl/certs

Alternatively build with the rustls feature, which uses a bundled root store and does not depend on the system OpenSSL cert layout.

License: MIT