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Instance Method

asyncStreamFile(at:chunkSize:mediaType:advancedETagComparison:onCompleted:)

Generates a chunked Response for the specified file. This method respects values in the "ETag" header and is capable of responding 304 Not Modified if the file in question has not been modified since last served. If advancedETagComparison is set to true, the response will have its ETag field set to a byte-by-byte hash of the requested file. If set to false, a simple ETag consisting of the last modified date and file size will be used. This method will also set the "Content-Type" header automatically if an appropriate MediaType can be found for the file’s suffix.
func asyncStreamFile(at path: String, chunkSize: Int = NonBlockingFileIO.defaultChunkSize, mediaType: HTTPMediaType? = nil, advancedETagComparison: Bool = false, onCompleted: @escaping @Sendable (Result<Void, Error>) async throws -> () = { _ in }) async throws -> Response

Parameters

path

Path to file on the disk.

chunkSize

Maximum size for the file data chunks.

mediaType

HTTPMediaType, if not specified, will be created from file extension.

advancedETagComparison

The method used when ETags are generated. If true, a byte-by-byte hash is created (and cached), otherwise a simple comparison based on the file’s last modified date and size.

onCompleted

Closure to be run on completion of stream.

Return Value

A 200 OK response containing the file stream and appropriate headers.

Discussion

app.get("file-stream") { req in
    return req.fileio.asyncStreamFile(at: "/path/to/file.txt")
}

Async equivalent of streamFile(at:chunkSize:mediaType:advancedETagComparison:onCompleted:) using Swift Concurrency functions under the hood