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 > ChunkTransformerPackage
@google-cloud/bigtableConstructors
(constructor)(options)
constructor(options?: TransformOptions);
Constructs a new instance of the ChunkTransformer
class
Parameter | |
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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 | |
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Name | Description |
cb |
Function
callback will be called with error if there is any uncommitted row |
Returns | |
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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 | |
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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 | |
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Type | Description |
void |
commit()
commit(): void;
sets lastRowkey and calls reset when row is committed.
Returns | |
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Type | Description |
void |
destroy(err)
destroy(err?: Error): this;
called when stream is destroyed.
Parameter | |
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Name | Description |
err |
Error
error if any |
Returns | |
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Type | Description |
this |
moveToNextState(chunk)
moveToNextState(chunk: Chunk): void;
Moves to next state in processing.
Parameter | |
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Name | Description |
chunk |
Chunk
chunk in process |
Returns | |
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Type | Description |
void |
processCellInProgress(chunk)
processCellInProgress(chunk: Chunk): void;
Process chunk when in CELl_IN_PROGRESS state.
Parameter | |
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Name | Description |
chunk |
Chunk
chunk to process |
Returns | |
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Type | Description |
void |
processNewRow(chunk)
processNewRow(chunk: Chunk): void;
Process chunk when in NEW_ROW state.
Parameter | |
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Name | Description |
chunk |
Chunk
chunk to process |
Returns | |
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Type | Description |
void |
processRowInProgress(chunk)
processRowInProgress(chunk: Chunk): void;
Process chunk when in ROW_IN_PROGRESS state.
Parameter | |
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Name | Description |
chunk |
Chunk
chunk to process |
Returns | |
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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 | |
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Name | Description |
chunk |
Chunk
chunk to validate |
Returns | |
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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 | |
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Type | Description |
void |
validateResetRow(chunk)
validateResetRow(chunk: Chunk): void;
Validates resetRow condition for chunk
Parameter | |
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Name | Description |
chunk |
Chunk
chunk to validate for resetrow |
Returns | |
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Type | Description |
void |
validateRowInProgress(chunk)
validateRowInProgress(chunk: Chunk): void;
Validates state for rowInProgress
Parameter | |
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Name | Description |
chunk |
Chunk
chunk to validate |
Returns | |
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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 | |
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Type | Description |
void |