Class ChunkTransformer (3.6.0)

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;
Property Value
Type Description
boolean

family

family?: Family;
Property Value
Type Description
Family

lastRowKey

lastRowKey?: Value;
Property Value
Type Description
Value

options

options: TransformOptions;
Property Value
Type Description
TransformOptions

qualifier

qualifier?: Qualifier;
Property Value
Type Description
Qualifier

qualifiers

qualifiers?: Qualifier[];
Property Value
Type Description
Qualifier[]

row

row?: Row;
Property Value
Type Description
Row

state

state?: number;
Property Value
Type Description
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, enc, next)

_transform(data: Data, enc: 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.
enc 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): void;

called when stream is destroyed.

Parameter
Name Description
err Error

error if any
Returns
Type Description
void

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

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