Class UploadSource

The content of a file to upload in chunks (see UploadAsync<TResult>(InterpolatedApiPathHandler, UploadSource, ReadOnlySpan<(string Name, object? Value)>, object?, UploadOptions?, CancellationToken) and UploadStreamingAsync<TItem>(InterpolatedApiPathHandler, UploadSource, ReadOnlySpan<(string Name, object? Value)>, object?, UploadOptions?, CancellationToken)), with its name, length and content type. It reads any byte range of the content, so that each chunk is read from where it starts.

Inheritance

object

UploadSource

Namespace: Singulink.Net.Http.Api.Client

Assembly: Singulink.Net.Http.Api.Client.dll

Syntax

public abstract class UploadSource

Remarks

An upload reads one range at a time, in order, each into the buffer of a chunk, and sends a chunk whose request fails again from that buffer. It reads a range again only for a chunk that the service still lacks when the upload completes.

FromFile(string, string?, string?), FromStream(Stream, string, string?), FromStreamFactory(string, long, Func<CancellationToken, Task<Stream>>, string?) and Create(string, long, Func<long, Memory<byte>, CancellationToken, ValueTask<int>>, string?) create sources. A derived class implements ReadAsync(long, Memory<byte>, CancellationToken), and ReleaseAsync() if it keeps something open between reads.

Constructors

Name	Description
UploadSource(string, long, string?)	Initializes a new instance of the UploadSource class with the specified file name, length and content type.

Properties

Name	Description
ContentType	Gets the content type of the file, such as image/png, which the service receives, or null if it has none.
FileName	Gets the name of the file, which the service receives.
Length	Gets the length of the content in bytes.

Methods

Name	Description
Create(string, long, Func<long, Memory<byte>, CancellationToken, ValueTask<int>>, string?)	Creates a source whose reads call the specified function.
FromFile(string, string?, string?)	Creates a source that reads a file. Each read opens the file and checks that its length and last write time are still the ones it had when the source was created, so that a file that changes fails the read with an IOException instead of being uploaded with other content. Other processes can read, write and delete the file while a read has it open.
FromStream(Stream, string, string?)	Creates a source that reads a seekable stream by setting its position, one read at a time. The content is the whole stream, whose length is read now. A read of a stream whose length has changed since throws an IOException. The stream is not disposed.
FromStreamFactory(string, long, Func<CancellationToken, Task<Stream>>, string?)	Creates a source that reads streams that a function opens, one read at a time. It keeps a stream open between reads and reads it forward, setting its position if it is seekable. It opens a new stream to go back in one that is not seekable, after a read fails, and after ReleaseAsync(). A stream whose length differs from length fails the read with an IOException.
ReadAsync(long, Memory<byte>, CancellationToken)	Reads bytes of the content, starting at the specified offset, into the buffer.
ReleaseAsync()	Releases what the source keeps open between reads, such as a stream. An upload calls it when it stops reading the source: once its chunks are sent, and when it fails or is cancelled. A later read opens what it needs again. An exception that it throws does not change how the upload goes on, and is traced as a warning (see Trace). Does nothing by default.