Class ChunkTransformer (6.0.0)

ChunkTransformer formats all incoming chunks in to row keeps all intermediate state until end of stream. Should use new instance for each request.

Inheritance

Transform > ChunkTransformer

Package

@google-cloud/bigtable

Constructors

(constructor)(options)

constructor(options?: TransformOptions);

Constructs a new instance of the ChunkTransformer class

Parameter
Name Description
options TransformOptions

Properties

_destroyed

_destroyed: boolean;

family

family?: Family;

lastRowKey

lastRowKey?: Value;

options

options: TransformOptions;

qualifier

qualifier?: Qualifier;

qualifiers

qualifiers?: Qualifier[];

row

row?: Row;

state

state?: number;

Methods

_flush(cb)

_flush(cb: Function): void;

called at end of the stream.

Parameter
Name Description
cb Function

callback will be called with error if there is any uncommitted row
Returns
Type Description
void

_transform(data, _encoding, next)

_transform(data: Data, _encoding: string, next: Function): void;

transform the readrowsresponse chunks into friendly format. Chunks contain 3 properties:

rowContents The row contents, this essentially is all data pertaining to a single family.

commitRow This is a boolean telling us the all previous chunks for this row are ok to consume.

resetRow This is a boolean telling us that all the previous chunks are to be discarded.

Parameters
Name Description
data Data

readrows response containing array of chunks.
_encoding string

encoding options.
next Function

callback will be called once data is processed, with error if any error in processing
Returns
Type Description
void

commit()

commit(): void;

sets lastRowkey and calls reset when row is committed.

Returns
Type Description
void

destroy(err)

destroy(err?: Error): this;

called when stream is destroyed.

Parameter
Name Description
err Error

error if any
Returns
Type Description
this

moveToNextState(chunk)

moveToNextState(chunk: Chunk): void;

Moves to next state in processing.

Parameter
Name Description
chunk Chunk

chunk in process
Returns
Type Description
void

processCellInProgress(chunk)

processCellInProgress(chunk: Chunk): void;

Process chunk when in CELl_IN_PROGRESS state.

Parameter
Name Description
chunk Chunk

chunk to process
Returns
Type Description
void

processNewRow(chunk)

processNewRow(chunk: Chunk): void;

Process chunk when in NEW_ROW state.

Parameter
Name Description
chunk Chunk

chunk to process
Returns
Type Description
void

processRowInProgress(chunk)

processRowInProgress(chunk: Chunk): void;

Process chunk when in ROW_IN_PROGRESS state.

Parameter
Name Description
chunk Chunk

chunk to process
Returns
Type Description
void

reset()

reset(): void;

Resets state of formatter

Returns
Type Description
void

validateCellInProgress(chunk)

validateCellInProgress(chunk: Chunk): void;

Validates chunk for cellInProgress state.

Parameter
Name Description
chunk Chunk

chunk to validate
Returns
Type Description
void

validateNewRow(chunk, newRowKey)

validateNewRow(chunk: Chunk, newRowKey: string | Buffer): void;

Validates state for new row.

Parameters
Name Description
chunk Chunk

chunk to validate
newRowKey string | "\"buffer\"".__global.Buffer

newRowKey of the new row
Returns
Type Description
void

validateResetRow(chunk)

validateResetRow(chunk: Chunk): void;

Validates resetRow condition for chunk

Parameter
Name Description
chunk Chunk

chunk to validate for resetrow
Returns
Type Description
void

validateRowInProgress(chunk)

validateRowInProgress(chunk: Chunk): void;

Validates state for rowInProgress

Parameter
Name Description
chunk Chunk

chunk to validate
Returns
Type Description
void

validateValueSizeAndCommitRow(chunk)

validateValueSizeAndCommitRow(chunk: Chunk): void;

Validates valuesize and commitrow in a chunk

Parameter
Name Description
chunk Chunk

chunk to validate for valuesize and commitRow
Returns
Type Description
void