Struct ReadStdin

pub struct ReadStdin {
    pub output: OutputPort<Bytes>,
    pub buffer_size: ByteSize,
}

A block that reads bytes from standard input (aka stdin).

Block Diagram

block-beta
    columns 4
    ReadStdin space:2 Sink
    ReadStdin-- "output" -->Sink

    classDef block height:48px,padding:8px;
    classDef hidden visibility:none;
    class ReadStdin block
    class Sink hidden

Sequence Diagram

sequenceDiagram
    autonumber
    participant ReadStdin as ReadStdin block
    participant ReadStdin.output as ReadStdin.output port
    participant BlockA as Another block

    ReadStdin-->>BlockA: Connect

    loop ReadStdin process
        ReadStdin->>ReadStdin: Read bytes from standard input
        ReadStdin->>BlockA: Message (Bytes)
    end

    ReadStdin-->>ReadStdin.output: Close
    ReadStdin-->>BlockA: Disconnect

Examples

Using the block in a system

System::build(|s| {
    let stdin = s.read_stdin();
    let stdout = s.write_stdout();
    s.connect(&stdin.output, &stdout.input);
});

Running the block via the CLI

$ protoflow execute ReadStdin < input.txt

$ protoflow execute ReadStdin buffer-size=1024 < input.txt

Fields

output: OutputPort<Bytes>

The output message stream.

buffer_size: ByteSize

The maximum number of bytes to read at a time.

Implementations

impl ReadStdin

pub fn new(output: OutputPort<Bytes>) -> Self

pub fn with_params( output: OutputPort<Bytes>, buffer_size: Option<ByteSize>, ) -> Self

pub fn with_system(system: &System, buffer_size: Option<ByteSize>) -> Self

Trait Implementations

impl Block for ReadStdin

fn execute(&mut self, runtime: &dyn BlockRuntime) -> BlockResult

Executes this block’s computation.

fn prepare(&mut self, _runtime: &dyn BlockRuntime) -> Result<(), BlockError>

Prepares this block for execution.

impl BlockDescriptor for ReadStdin

fn inputs(&self) -> Vec<PortDescriptor>

A description of this block’s input ports.

fn outputs(&self) -> Vec<PortDescriptor>

A description of this block’s output ports.

fn parameters(&self) -> Vec<ParameterDescriptor>

A description of this block’s parameters.

fn ports(&self) -> Vec<PortDescriptor>

A description of this block’s I/O ports.

impl Clone for ReadStdin

fn clone(&self) -> ReadStdin

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl MaybeLabeled for ReadStdin

fn label(&self) -> Option<Cow<'_, str>>

Returns the human-readable label, if any, of the object.

fn is_labeled(&self) -> bool

Checks whether the object has a human-readable label.

impl MaybeNamed for ReadStdin

fn name(&self) -> Option<Cow<'_, str>>

Returns the name, if any, of the object.

fn is_named(&self) -> bool

Checks whether the object has a name.

impl StdioSystem for ReadStdin

fn build_system(config: StdioConfig) -> Result<System, StdioError>