class Google::Cloud::Bigtable::RowFilter::ChainFilter

# ChainFilter

A RowFilter that sends rows through several RowFilters in sequence.

The elements of “filters” are chained together to process the input row:

in row -> f(0) -> intermediate row -> f(1) -> ... -> f(N) -> out row

The full chain is executed atomically.

@example

require "google/cloud/bigtable"

chain = Google::Cloud::Bigtable::RowFilter.chain
# Add filters to chain filter
chain.key("user-*").label "users"

Public Class Methods

new() click to toggle source

@private Creates an instance of a chain filter.

# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 43
def initialize
  @filters = []
end

Public Instance Methods

block() click to toggle source

Adds a block-all filter.

Does not match any cells, regardless of input. Useful for temporarily disabling just part of a filter.

@return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.block
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 202
def block
  add RowFilter.block
end
cells_per_column(limit) click to toggle source

Adds a cells-per-column filter.

Matches only the most recent N cells within each column. For example, if N=2, this filter would match column `foo:bar` at timestamps 10 and 9, skip all earlier cells in `foo:bar`, and then begin matching again in column `foo:bar2`. If duplicate cells are present, as is possible when using an Interleave, each copy of the cell is counted separately.

@param limit [String] Max cell match per column limit. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.cells_per_column 5
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 452
def cells_per_column limit
  add RowFilter.cells_per_column(limit)
end
cells_per_row(limit) click to toggle source

Adds a cells-per-row-limit filter.

Matches only the first N cells of each row. If duplicate cells are present, as is possible when using an Interleave, each copy of the cell is counted separately.

@param limit [String] Max cell match per row limit. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.cells_per_row 5
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 429
def cells_per_row limit
  add RowFilter.cells_per_row(limit)
end
cells_per_row_offset(offset) click to toggle source

Adds a cell-per-row-offset filter instance to skip the first N cells.

Skips the first N cells of each row, matching all subsequent cells. If duplicate cells are present, as is possible when using an Interleave, each copy of the cell is counted separately.

@param offset [Integer] Offset value. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.cells_per_row_offset 3
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 409
def cells_per_row_offset offset
  add RowFilter.cells_per_row_offset(offset)
end
chain(filter) click to toggle source

Adds a chain filter.

A Chain RowFilter that sends rows through several RowFilters in sequence.

The elements of “filters” are chained together to process the input row:

in row -> f(0) -> intermediate row -> f(1) -> ... -> f(N) -> out row

The full chain is executed atomically.

@param filter [SimpleFilter, ChainFilter, InterleaveFilter, ConditionFilter] @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example Create a chain filter and add a chain filter.

require "google/cloud/bigtable"

chain_1 = Google::Cloud::Bigtable::RowFilter.chain

# Add filters to chain filter
chain_1.key("user-*").cells_per_row 5

filter = Google::Cloud::Bigtable::RowFilter.chain
filter.chain chain_1

# OR
filter = Google::Cloud::Bigtable::RowFilter.chain.chain chain_1
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 76
def chain filter
  raise RowFilterError, "Filter type must be ChainFilter" unless filter.instance_of? ChainFilter
  add filter
end
column_range(range) click to toggle source

Adds a column-range filter.

Matches only cells from columns within the given range.

@param range [Google::Cloud::Bigtable::ColumnRange] @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

range = Google::Cloud::Bigtable::ColumnRange.new("cf").from("field0").to("field5")

filter = Google::Cloud::Bigtable::RowFilter.chain.column_range range
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 536
def column_range range
  add RowFilter.column_range(range)
end
condition(filter) click to toggle source

Adds a condition filter.

A RowFilter that evaluates one of two possible RowFilters, depending on whether or not a predicate RowFilter outputs any cells from the input row.

IMPORTANT NOTE: The predicate filter does not execute atomically with the true and false filters, which may lead to inconsistent or unexpected results. Additionally, condition filters have poor performance, especially when filters are set for the false condition.

Cannot be used within the `predicate_filter`, `true_filter`, or `false_filter`.

@param filter [Google::Cloud::Bigtable::RowFilter::ConditionFilter] @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

predicate = Google::Cloud::Bigtable::RowFilter.key "user-*"

label = Google::Cloud::Bigtable::RowFilter.label "user"
strip_value = Google::Cloud::Bigtable::RowFilter.strip_value

condition_filter = Google::Cloud::Bigtable::RowFilter.condition(predicate)
                                                     .on_match(label)
                                                     .otherwise(strip_value)

filter = Google::Cloud::Bigtable::RowFilter.chain.condition condition_filter
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 165
def condition filter
  raise RowFilterError, "Filter type must be ConditionFilter" unless filter.instance_of? ConditionFilter
  add filter
end
family(regex) click to toggle source

Adds a family-name-match filter using a regular expression.

Matches only cells from columns whose families satisfy the given RE2 regex. For technical reasons, the regex must not contain the `:` character, even if it is not being used as a literal. Note that, since column families cannot contain the new line character `n`, it is sufficient to use `.` as a full wildcard when matching column family names.

For Regex syntax: @see github.com/google/re2/wiki/Syntax

@param regex [String] Regex to match family name. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.family "cf-*"
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 309
def family regex
  add RowFilter.family(regex)
end
filters() click to toggle source

Returns a frozen copy of the filters array.

@return [Array<SimpleFilter|ChainFilter|InterleaveFilter|ConditionFilter>]

# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 560
def filters
  @filters.dup.freeze
end
interleave(filter) click to toggle source

Adds an interleave filter.

A RowFilter that sends each row to each of several component RowFilters and interleaves the results.

The elements of “filters” all process a copy of the input row, and the results are pooled, sorted, and combined into a single output row. If multiple cells are produced with the same column and timestamp, they will all appear in the output row in an unspecified mutual order. Consider the following example, with three filters:

                             input row
                                 |
       -----------------------------------------------------
       |                         |                         |
      f(0)                      f(1)                      f(2)
       |                         |                         |
1: foo,bar,10,x             foo,bar,10,z              far,bar,7,a
2: foo,blah,11,z            far,blah,5,x              far,blah,5,x
       |                         |                         |
       -----------------------------------------------------
                                 |
1:                      foo,bar,10,z   # could have switched with #2
2:                      foo,bar,10,x   # could have switched with #1
3:                      foo,blah,11,z
4:                      far,bar,7,a
5:                      far,blah,5,x   # identical to #6
6:                      far,blah,5,x   # identical to #5

All interleaved filters are executed atomically.

See {Google::Cloud::Bigtable::RowFilter::InterleaveFilter}

@param filter [SimpleFilter, ChainFilter, InterleaveFilter, ConditionFilter] @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example Add an interleave filter to the chain filter.

require "google/cloud/bigtable"

interleave = Google::Cloud::Bigtable::RowFilter.interleave

# Add filters to interleave filter
interleave.key("user-*").cells_per_column(3)

chain = Google::Cloud::Bigtable::RowFilter.chain.interleave interleave
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 129
def interleave filter
  raise RowFilterError, "Filter type must be InterleaveFilter" unless filter.instance_of? InterleaveFilter
  add filter
end
key(regex) click to toggle source

Adds a key-filter instance to match keys using a regular expression.

Matches only cells from rows whose keys satisfy the given RE2 regex. In other words, passes through the entire row when the key matches, and otherwise produces an empty row. Note that, since row keys can contain arbitrary bytes, the `C` escape sequence must be used if a true wildcard is desired. The `.` character will not match the new line character `n`, which may be present in a binary key.

For Regex syntax: @see github.com/google/re2/wiki/Syntax

@param regex [String] Regex to match row keys. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.key "user-*"
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 263
def key regex
  add RowFilter.key(regex)
end
label(value) click to toggle source

Adds a label filter instance to apply a label based on the result of read rows.

Applies the given label to all cells in the output row. This allows the client to determine which results were produced from which part of the filter.

Values must be at most 15 characters and match the RE2 pattern `[a-z0-9\-]+`

Due to a technical limitation, it is not possible to apply multiple labels to a cell. As a result, a chain may have no more than one sub-filter that contains an `apply_label_transformer`. It is okay for an Interleave to contain multiple `apply_label_transformers`, as they will be applied to separate copies of the input.

@param value [String] Label name @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.label "user-detail"
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 389
def label value
  add RowFilter.label(value)
end
length() click to toggle source

Gets the number of filters in the chain.

@return [Integer]

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.key("user-1*").label("user")
filter.length # 2
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 551
def length
  @filters.length
end
pass() click to toggle source

Adds a pass filter.

Matches all cells, regardless of input. Functionally equivalent to leaving `filter` unset, but included for completeness.

@return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.pass
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 184
def pass
  add RowFilter.pass
end
qualifier(regex) click to toggle source

Adds a column-qualifier-match filter using a regular expression.

Matches only cells from columns whose qualifiers satisfy the given RE2 regex. Note that, since column qualifiers can contain arbitrary bytes, the `C` escape sequence must be used if a true wildcard is desired. The `.` character will not match the new line character `n`, which may be present in a binary qualifier.

For Regex syntax: @see github.com/google/re2/wiki/Syntax

@param regex [String] Regex to match column qualifier name. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.qualifier "user-name*"
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 335
def qualifier regex
  add RowFilter.qualifier(regex)
end
sample(probability) click to toggle source

Adds a sample-probability filter.

Matches all cells from a row with probability p, and matches no cells from the row with probability 1-p.

@param probability [Float] Probability value.

Probability must be greater than 0 and less than 1.0.

@return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.sample 0.5
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 283
def sample probability
  add RowFilter.sample(probability)
end
sink() click to toggle source

Adds a sink filter.

Outputs all cells directly to the output of the read rather than to any parent filter.

@return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.sink
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 219
def sink
  add RowFilter.sink
end
strip_value() click to toggle source

Adds a strip-value filter.

Replaces each cell's value with an empty string.

@return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.strip_value
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 236
def strip_value
  add RowFilter.strip_value
end
timestamp_range(from: nil, to: nil) click to toggle source

Adds a timestamp-range filter.

Matches only cells with timestamps within the given range. Specifies a contiguous range of timestamps.

@param from [Integer] Inclusive lower bound.

If left empty, interpreted as 0.

@param to [Integer] Exclusive upper bound.

If left empty, interpreted as infinity.

@return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

timestamp_micros = (Time.now.to_f * 1_000_000).round(-3)
from = timestamp_micros - 300_000_000
to = timestamp_micros

filter = Google::Cloud::Bigtable::RowFilter.chain.timestamp_range from: from, to: to
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 478
def timestamp_range from: nil, to: nil
  add RowFilter.timestamp_range(from: from, to: to)
end
to_grpc() click to toggle source

@private

Gets a gRPC object of RowFilter with a chain filter.

@return [Google::Cloud::Bigtable::V2::RowFilter]

# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 570
def to_grpc
  Google::Cloud::Bigtable::V2::RowFilter.new(
    chain: Google::Cloud::Bigtable::V2::RowFilter::Chain.new(filters: @filters.map(&:to_grpc))
  )
end
value(regex) click to toggle source

Adds a value-match filter using a regular expression.

Matches only cells with values that satisfy the given regular expression. Note that, since cell values can contain arbitrary bytes, the `C` escape sequence must be used if a true wildcard is desired. The `.` character will not match the new line character `n`, which may be present in a binary value.

For Regex syntax: @see github.com/google/re2/wiki/Syntax

@param regex [String] Regex to match cell value. @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example

require "google/cloud/bigtable"

filter = Google::Cloud::Bigtable::RowFilter.chain.value "abc*"
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 360
def value regex
  add RowFilter.value(regex)
end
value_range(range) click to toggle source

Adds a value-range filter.

Matches only cells with values that fall within the given range.

See {Google::Cloud::Bigtable::ValueRange#from} and { Google::Cloud::Bigtable::ValueRange#to} for range option inclusive/exclusive options.

  • The value at which to start the range. If neither field is set, interpreted as an empty string, inclusive.

  • The value at which to end the range. If neither field is set, interpreted as the infinite string, exclusive.

@param range [Google::Cloud::Bigtable::ValueRange] @return [Google::Cloud::Bigtable::RowFilter::ChainFilter]

`self` instance of chain filter.

@example Start to end range.

require "google/cloud/bigtable"

bigtable = Google::Cloud::Bigtable.new
table = bigtable.table "my-instance", "my-table"

range = table.new_value_range.from("value-001").to("value-005")
filter = Google::Cloud::Bigtable::RowFilter.chain.value_range range

@example Start exclusive to infinite end range.

require "google/cloud/bigtable"

bigtable = Google::Cloud::Bigtable.new
table = bigtable.table "my-instance", "my-table"

range = table.new_value_range.from "value-001", inclusive: false
filter = Google::Cloud::Bigtable::RowFilter.chain.value_range range
# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 516
def value_range range
  add RowFilter.value_range(range)
end

Private Instance Methods

add(filter) click to toggle source

@private Adds a filter to a chain.

@param filter [SimpleFilter, ChainFilter, InterleaveFilter, ConditionFilter]

# File lib/google/cloud/bigtable/row_filter/chain_filter.rb, line 583
def add filter
  @filters << filter
  self
end