Struct NamedFile

pub struct NamedFile { /* private fields */ }

A file with an associated name.

NamedFile can be registered as services:

use actix_web::App;
use actix_files::NamedFile;

let file = NamedFile::open_async("./static/index.html").await?;
let app = App::new().service(file);

They can also be returned from handlers:

use actix_web::{Responder, get};
use actix_files::NamedFile;

#[get("/")]
async fn index() -> impl Responder {
    NamedFile::open_async("./static/index.html").await
}

Implementations

impl NamedFile

pub fn from_file<P: AsRef<Path>>(file: File, path: P) -> Result<NamedFile>

Creates an instance from a previously opened file.

The given path need not exist and is only used to determine the ContentType and ContentDisposition headers.

Examples

use std::{
    io::{self, Write as _},
    env,
    fs::File
};
use actix_files::NamedFile;

let mut file = File::create("foo.txt")?;
file.write_all(b"Hello, world!")?;
let named_file = NamedFile::from_file(file, "bar.txt")?;
Ok(())

pub fn open<P: AsRef<Path>>(path: P) -> Result<NamedFile>

Attempts to open a file in read-only mode.

Examples

use actix_files::NamedFile;
let file = NamedFile::open("foo.txt");

pub async fn open_async<P: AsRef<Path>>(path: P) -> Result<NamedFile>

Attempts to open a file asynchronously in read-only mode.

When the experimental-io-uring crate feature is enabled, this will be async. Otherwise, it will behave just like open.

Examples

use actix_files::NamedFile;
let file = NamedFile::open_async("foo.txt").await.unwrap();

pub fn file(&self) -> &File

Returns reference to the underlying file object.

pub fn path(&self) -> &Path

Returns the filesystem path to this file.

Examples

use actix_files::NamedFile;

let file = NamedFile::open_async("test.txt").await?;
assert_eq!(file.path().as_os_str(), "foo.txt");

pub fn modified(&self) -> Option<SystemTime>

Returns the time the file was last modified.

Returns None only on unsupported platforms; see std::fs::Metadata::modified(). Therefore, it is usually safe to unwrap this.

pub fn metadata(&self) -> &Metadata

Returns the filesystem metadata associated with this file.

pub fn content_type(&self) -> &Mime

Returns the Content-Type header that will be used when serving this file.

pub fn content_disposition(&self) -> &ContentDisposition

Returns the Content-Disposition that will be used when serving this file.

pub fn content_encoding(&self) -> Option<ContentEncoding>

Returns the Content-Encoding that will be used when serving this file.

A return value of None indicates that the content is not already using a compressed representation and may be subject to compression downstream.

pub fn set_status_code(self, status: StatusCode) -> Self

👎Deprecated since 0.7.0: Prefer Responder::customize().

Set response status code.

pub fn set_content_type(self, mime_type: Mime) -> Self

Sets the Content-Type header that will be used when serving this file. By default the Content-Type is inferred from the filename extension.

pub fn set_content_disposition(self, cd: ContentDisposition) -> Self

Set the Content-Disposition for serving this file. This allows changing the inline/attachment disposition as well as the filename sent to the peer.

By default the disposition is inline for text/*, image/*, video/* and application/{javascript, json, wasm} mime types, and attachment otherwise, and the filename is taken from the path provided in the open method after converting it to UTF-8 (using to_string_lossy).

pub fn disable_content_disposition(self) -> Self

Disables Content-Disposition header.

By default, the Content-Disposition header is sent.

pub fn set_content_encoding(self, enc: ContentEncoding) -> Self

Sets content encoding for this file.

This prevents the Compress middleware from modifying the file contents and signals to browsers/clients how to decode it. For example, if serving a compressed HTML file (e.g., index.html.gz) then use .set_content_encoding(ContentEncoding::Gzip).

pub fn read_mode_threshold(self, size: u64) -> Self

Sets the size threshold that determines file read mode (sync/async).

When a file is smaller than the threshold (bytes), the reader will switch from synchronous (blocking) file-reads to async reads to avoid blocking the main-thread when processing large files.

Tweaking this value according to your expected usage may lead to signifiant performance gains (or losses in other handlers, if size is too high).

When the experimental-io-uring crate feature is enabled, file reads are always async.

Default is 0, meaning all files are read asynchronously.

pub fn use_etag(self, value: bool) -> Self

Specifies whether to return ETag header in response.

Default is true.

pub fn use_last_modified(self, value: bool) -> Self

Specifies whether to return Last-Modified header in response.

Default is true.

pub fn prefer_utf8(self, value: bool) -> Self

Specifies whether text responses should signal a UTF-8 encoding.

Default is false (but will default to true in a future version).

pub fn into_response(self, req: &HttpRequest) -> HttpResponse<BoxBody>

Creates an HttpResponse with file as a streaming body.

Methods from Deref<Target = File>

pub fn sync_all(&self) -> Result<(), Error>

Attempts to sync all OS-internal file content and metadata to disk.

This function will attempt to ensure that all in-memory data reaches the filesystem before returning.

This can be used to handle errors that would otherwise only be caught when the File is closed, as dropping a File will ignore all errors. Note, however, that sync_all is generally more expensive than closing a file by dropping it, because the latter is not required to block until the data has been written to the filesystem.

If synchronizing the metadata is not required, use sync_data instead.

Examples

use std::fs::File;
use std::io::prelude::*;

fn main() -> std::io::Result<()> {
    let mut f = File::create("foo.txt")?;
    f.write_all(b"Hello, world!")?;

    f.sync_all()?;
    Ok(())
}

pub fn sync_data(&self) -> Result<(), Error>

This function is similar to sync_all, except that it might not synchronize file metadata to the filesystem.

This is intended for use cases that must synchronize content, but don’t need the metadata on disk. The goal of this method is to reduce disk operations.

Note that some platforms may simply implement this in terms of sync_all.

Examples

use std::fs::File;
use std::io::prelude::*;

fn main() -> std::io::Result<()> {
    let mut f = File::create("foo.txt")?;
    f.write_all(b"Hello, world!")?;

    f.sync_data()?;
    Ok(())
}

pub fn lock(&self) -> Result<(), Error>

Acquire an exclusive lock on the file. Blocks until the lock can be acquired.

This acquires an exclusive lock; no other file handle to this file may acquire another lock.

This lock may be advisory or mandatory. This lock is meant to interact with lock, try_lock, lock_shared, try_lock_shared, and unlock. Its interactions with other methods, such as read and write are platform specific, and it may or may not cause non-lockholders to block.

If this file handle/descriptor, or a clone of it, already holds an lock the exact behavior is unspecified and platform dependent, including the possibility that it will deadlock. However, if this method returns, then an exclusive lock is held.

If the file not open for writing, it is unspecified whether this function returns an error.

The lock will be released when this file (along with any other file descriptors/handles duplicated or inherited from it) is closed, or if the unlock method is called.

Platform-specific behavior

This function currently corresponds to the flock function on Unix with the LOCK_EX flag, and the LockFileEx function on Windows with the LOCKFILE_EXCLUSIVE_LOCK flag. Note that, this may change in the future.

On Windows, locking a file will fail if the file is opened only for append. To lock a file, open it with one of .read(true), .read(true).append(true), or .write(true).

Examples

use std::fs::File;

fn main() -> std::io::Result<()> {
    let f = File::create("foo.txt")?;
    f.lock()?;
    Ok(())
}

pub fn lock_shared(&self) -> Result<(), Error>

Acquire a shared (non-exclusive) lock on the file. Blocks until the lock can be acquired.

This acquires a shared lock; more than one file handle may hold a shared lock, but none may hold an exclusive lock at the same time.

This lock may be advisory or mandatory. This lock is meant to interact with lock, try_lock, lock_shared, try_lock_shared, and unlock. Its interactions with other methods, such as read and write are platform specific, and it may or may not cause non-lockholders to block.

If this file handle/descriptor, or a clone of it, already holds an lock, the exact behavior is unspecified and platform dependent, including the possibility that it will deadlock. However, if this method returns, then a shared lock is held.

The lock will be released when this file (along with any other file descriptors/handles duplicated or inherited from it) is closed, or if the unlock method is called.

Platform-specific behavior

This function currently corresponds to the flock function on Unix with the LOCK_SH flag, and the LockFileEx function on Windows. Note that, this may change in the future.

On Windows, locking a file will fail if the file is opened only for append. To lock a file, open it with one of .read(true), .read(true).append(true), or .write(true).

Examples

use std::fs::File;

fn main() -> std::io::Result<()> {
    let f = File::open("foo.txt")?;
    f.lock_shared()?;
    Ok(())
}

pub fn try_lock(&self) -> Result<(), TryLockError>

Try to acquire an exclusive lock on the file.

Returns Err(TryLockError::WouldBlock) if a different lock is already held on this file (via another handle/descriptor).

This acquires an exclusive lock; no other file handle to this file may acquire another lock.

This lock may be advisory or mandatory. This lock is meant to interact with lock, try_lock, lock_shared, try_lock_shared, and unlock. Its interactions with other methods, such as read and write are platform specific, and it may or may not cause non-lockholders to block.

If this file handle/descriptor, or a clone of it, already holds an lock, the exact behavior is unspecified and platform dependent, including the possibility that it will deadlock. However, if this method returns Ok(true), then it has acquired an exclusive lock.

If the file not open for writing, it is unspecified whether this function returns an error.

The lock will be released when this file (along with any other file descriptors/handles duplicated or inherited from it) is closed, or if the unlock method is called.

Platform-specific behavior

This function currently corresponds to the flock function on Unix with the LOCK_EX and LOCK_NB flags, and the LockFileEx function on Windows with the LOCKFILE_EXCLUSIVE_LOCK and LOCKFILE_FAIL_IMMEDIATELY flags. Note that, this may change in the future.

On Windows, locking a file will fail if the file is opened only for append. To lock a file, open it with one of .read(true), .read(true).append(true), or .write(true).

Examples

use std::fs::{File, TryLockError};

fn main() -> std::io::Result<()> {
    let f = File::create("foo.txt")?;
    // Explicit handling of the WouldBlock error
    match f.try_lock() {
        Ok(_) => (),
        Err(TryLockError::WouldBlock) => (), // Lock not acquired
        Err(TryLockError::Error(err)) => return Err(err),
    }
    // Alternately, propagate the error as an io::Error
    f.try_lock()?;
    Ok(())
}

pub fn try_lock_shared(&self) -> Result<(), TryLockError>

Try to acquire a shared (non-exclusive) lock on the file.

Returns Err(TryLockError::WouldBlock) if a different lock is already held on this file (via another handle/descriptor).

This acquires a shared lock; more than one file handle may hold a shared lock, but none may hold an exclusive lock at the same time.

This lock may be advisory or mandatory. This lock is meant to interact with lock, try_lock, lock_shared, try_lock_shared, and unlock. Its interactions with other methods, such as read and write are platform specific, and it may or may not cause non-lockholders to block.

If this file handle, or a clone of it, already holds an lock, the exact behavior is unspecified and platform dependent, including the possibility that it will deadlock. However, if this method returns Ok(true), then it has acquired a shared lock.

The lock will be released when this file (along with any other file descriptors/handles duplicated or inherited from it) is closed, or if the unlock method is called.

Platform-specific behavior

This function currently corresponds to the flock function on Unix with the LOCK_SH and LOCK_NB flags, and the LockFileEx function on Windows with the LOCKFILE_FAIL_IMMEDIATELY flag. Note that, this may change in the future.

On Windows, locking a file will fail if the file is opened only for append. To lock a file, open it with one of .read(true), .read(true).append(true), or .write(true).

Examples

use std::fs::{File, TryLockError};

fn main() -> std::io::Result<()> {
    let f = File::open("foo.txt")?;
    // Explicit handling of the WouldBlock error
    match f.try_lock_shared() {
        Ok(_) => (),
        Err(TryLockError::WouldBlock) => (), // Lock not acquired
        Err(TryLockError::Error(err)) => return Err(err),
    }
    // Alternately, propagate the error as an io::Error
    f.try_lock_shared()?;

    Ok(())
}

pub fn unlock(&self) -> Result<(), Error>

Release all locks on the file.

All locks are released when the file (along with any other file descriptors/handles duplicated or inherited from it) is closed. This method allows releasing locks without closing the file.

If no lock is currently held via this file descriptor/handle, this method may return an error, or may return successfully without taking any action.

Platform-specific behavior

This function currently corresponds to the flock function on Unix with the LOCK_UN flag, and the UnlockFile function on Windows. Note that, this may change in the future.

On Windows, locking a file will fail if the file is opened only for append. To lock a file, open it with one of .read(true), .read(true).append(true), or .write(true).

Examples

use std::fs::File;

fn main() -> std::io::Result<()> {
    let f = File::open("foo.txt")?;
    f.lock()?;
    f.unlock()?;
    Ok(())
}

pub fn set_len(&self, size: u64) -> Result<(), Error>

Truncates or extends the underlying file, updating the size of this file to become size.

If the size is less than the current file’s size, then the file will be shrunk. If it is greater than the current file’s size, then the file will be extended to size and have all of the intermediate data filled in with 0s.

The file’s cursor isn’t changed. In particular, if the cursor was at the end and the file is shrunk using this operation, the cursor will now be past the end.

Errors

This function will return an error if the file is not opened for writing. Also, std::io::ErrorKind::InvalidInput will be returned if the desired length would cause an overflow due to the implementation specifics.

Examples

use std::fs::File;

fn main() -> std::io::Result<()> {
    let mut f = File::create("foo.txt")?;
    f.set_len(10)?;
    Ok(())
}

Note that this method alters the content of the underlying file, even though it takes &self rather than &mut self.

pub fn metadata(&self) -> Result<Metadata, Error>

Queries metadata about the underlying file.

Examples

use std::fs::File;

fn main() -> std::io::Result<()> {
    let mut f = File::open("foo.txt")?;
    let metadata = f.metadata()?;
    Ok(())
}

pub fn try_clone(&self) -> Result<File, Error>

Creates a new File instance that shares the same underlying file handle as the existing File instance. Reads, writes, and seeks will affect both File instances simultaneously.

Examples

Creates two handles for a file named foo.txt:

use std::fs::File;

fn main() -> std::io::Result<()> {
    let mut file = File::open("foo.txt")?;
    let file_copy = file.try_clone()?;
    Ok(())
}

Assuming there’s a file named foo.txt with contents abcdef\n, create two handles, seek one of them, and read the remaining bytes from the other handle:

use std::fs::File;
use std::io::SeekFrom;
use std::io::prelude::*;

fn main() -> std::io::Result<()> {
    let mut file = File::open("foo.txt")?;
    let mut file_copy = file.try_clone()?;

    file.seek(SeekFrom::Start(3))?;

    let mut contents = vec![];
    file_copy.read_to_end(&mut contents)?;
    assert_eq!(contents, b"def\n");
    Ok(())
}

pub fn set_permissions(&self, perm: Permissions) -> Result<(), Error>

Changes the permissions on the underlying file.

Platform-specific behavior

This function currently corresponds to the fchmod function on Unix and the SetFileInformationByHandle function on Windows. Note that, this may change in the future.

Errors

This function will return an error if the user lacks permission change attributes on the underlying file. It may also return an error in other os-specific unspecified cases.

Examples

fn main() -> std::io::Result<()> {
    use std::fs::File;

    let file = File::open("foo.txt")?;
    let mut perms = file.metadata()?.permissions();
    perms.set_readonly(true);
    file.set_permissions(perms)?;
    Ok(())
}

Note that this method alters the permissions of the underlying file, even though it takes &self rather than &mut self.

pub fn set_times(&self, times: FileTimes) -> Result<(), Error>

Changes the timestamps of the underlying file.

Platform-specific behavior

This function currently corresponds to the futimens function on Unix (falling back to futimes on macOS before 10.13) and the SetFileTime function on Windows. Note that this may change in the future.

Errors

This function will return an error if the user lacks permission to change timestamps on the underlying file. It may also return an error in other os-specific unspecified cases.

This function may return an error if the operating system lacks support to change one or more of the timestamps set in the FileTimes structure.

Examples

fn main() -> std::io::Result<()> {
    use std::fs::{self, File, FileTimes};

    let src = fs::metadata("src")?;
    let dest = File::options().write(true).open("dest")?;
    let times = FileTimes::new()
        .set_accessed(src.accessed()?)
        .set_modified(src.modified()?);
    dest.set_times(times)?;
    Ok(())
}

pub fn set_modified(&self, time: SystemTime) -> Result<(), Error>

Changes the modification time of the underlying file.

This is an alias for set_times(FileTimes::new().set_modified(time)).

Trait Implementations

impl Debug for NamedFile

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Deref for NamedFile

type Target = File

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl DerefMut for NamedFile

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl HttpServiceFactory for NamedFile

fn register(self, config: &mut AppService)

impl Responder for NamedFile

type Body = BoxBody

fn respond_to(self, req: &HttpRequest) -> HttpResponse<Self::Body>

Convert self to HttpResponse.

fn customize(self) -> CustomizeResponder<Self>

where Self: Sized,

Wraps responder to allow alteration of its response.

impl ServiceFactory<ServiceRequest> for NamedFile

type Response = ServiceResponse

Responses given by the created services.

type Error = Error

Errors produced by the created services.

type Config = ()

Service factory configuration.

type Service = NamedFileService

The kind of Service created by this factory.

type InitError = ()

Errors potentially raised while building a service.

type Future = Pin<Box<dyn Future<Output = Result<<NamedFile as ServiceFactory<ServiceRequest>>::Service, <NamedFile as ServiceFactory<ServiceRequest>>::InitError>>>>

The future of the Service instance.g

fn new_service(&self, _: ()) -> Self::Future

Create and return a new service asynchronously.