Class ChunkTransformer (3.8.0)

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, 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): 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 \| __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