import ReadStream from 'atscm/src/lib/server/ReadStream.js'

public class | source

ReadStream

Stream → QueueStream → ReadStream

A stream that reads atvise server nodes for the node-opcua~ReferenceDescriptions passed.

Method Summary

Public Methods
public	processChunk(browseResult: NodeStream.BrowseResult, handleErrors: function(err: Error, status: node-opcua~StatusCodes, success: function)) Returns a ReadStream.ReadResult for the given NodeStream.BrowseResult.
public	processErrorMessage(referenceDescription: node-opcua~ReferenceDescription): string Returns an error message specifically for the given reference description.

From class Stream
private	_keepSessionAlive: Boolean `true` if the stream's atvise server session should be kept alive once the stream ends.
private	_flush(callback: function(err: ?Error, data: Object)) Called just before the stream is closed: Closes the open session.

From class QueueStream
public get	hasPending: boolean `true` if there are queued operations or an operation is running right now.
public get	opsPerSecond: number The number of processed chunks per second.
public get	processed: number The number of chunks already processed.
public get	queueEmpty: boolean `true` if there are no queued operations.
private	_maxParallel: number The maximum of parallel tasks to execute
private	_processed: Number The number of chunks processed so far.
private	_processing: Number The number of running operations.
private	_queued: *[] The queued chunks.
private	_start: Number The timestamp of the date when the stream was created.
public abstract	processChunk(chunk: *, handleErrors: function(err: Error, statusCode: node-opcua~StatusCodes, onSuccess: function)) The function to call when a chunk is ready to be processed.
public abstract	processErrorMessage(chunk: *): string The error message to use when processing a chunk fails.
private	_enqueueChunk(chunk: *) Enqueues the given chunk for processing.
private	_flush(callback: Function) Waits for pending operations to complete.
private	_processChunk(chunk: *) Calls QueueStream#processChunk and handles errors and invalid status codes.
private	_transform(chunk: *, enc: string, callback: Function) Calls QueueStream#_enqueueChunk as soon as the stream's session is opened.

Name	Type	Attribute	Description
browseResult	NodeStream.BrowseResult		The browse result to process: If NodeStream.BrowseResult#nodeClass equals node-opcua~NodeClass.Variable the browse result is passed as-is to piped streams. Otherwise the node's value is read from atvise server.
handleErrors	function(err: Error, status: node-opcua~StatusCodes, success: function)		The error handler to call. See QueueStream#processChunk for details.

Name

Type

Attribute

Description

browseResult

The browse result to process:

If NodeStream.BrowseResult#nodeClass equals node-opcua~NodeClass.Variable the browse result is passed as-is to piped streams.
Otherwise the node's value is read from atvise server.

handleErrors

The error handler to call. See QueueStream#processChunk for details.

Returns an error message specifically for the given reference description.

Name	Type	Attribute	Description
referenceDescription	node-opcua~ReferenceDescription		The reference description to get the error message for.

The specific error message.