Module: ClickHouse::Client::Redactor

Defined in:
lib/click_house/client/redactor.rb

Class Method Summary collapse

Class Method Details

.redact(query_builder, bind_manager = ClickHouse::Client::BindIndexManager.new) ⇒ String

Redacts the SQL query represented by the query builder.

Example:

query_builder = ClickHouse::QueryBuilder.new('users').where(name: 'John Doe')
redacted_query = ClickHouse::Redactor.redact(query_builder)
# The redacted_query will contain the SQL query with values replaced by placeholders.
output: "SELECT * FROM \"users\" WHERE \"users\".\"name\" = $1"

Parameters:

  • query_builder (::ClickHouse::Querybuilder) —

    The query builder object to be redacted.

Returns:

  • (String) —

    The redacted SQL query as a string.

Raises:

  • (ArgumentError) —

    when the condition in the query is of an unsupported type.



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# File 'lib/click_house/client/redactor.rb', line 17

def self.redact(query_builder, bind_manager = ClickHouse::Client::BindIndexManager.new)
  cloned_query_builder = query_builder.clone

  cloned_query_builder.conditions = cloned_query_builder.conditions.map do |condition|
    redact_condition(condition, bind_manager)
  end

  cloned_query_builder.manager.constraints.clear
  cloned_query_builder.conditions.each do |condition|
    cloned_query_builder.manager.where(condition)
  end

  visitor = Arel::Visitors::ToSql.new(ClickHouse::Client::ArelEngine.new)
  visitor.accept(cloned_query_builder.manager.ast, Arel::Collectors::SQLString.new).value
end

.redact_condition(condition, bind_manager) ⇒ Object 



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# File 'lib/click_house/client/redactor.rb', line 33

def self.redact_condition(condition, bind_manager)
  case condition
  when Arel::Nodes::In
    condition.left.in(Array.new(condition.right.size) { Arel.sql(bind_manager.next_bind_str) })
  when Arel::Nodes::Equality
    condition.left.eq(Arel.sql(bind_manager.next_bind_str))
  when Arel::Nodes::LessThan
    condition.left.lt(Arel.sql(bind_manager.next_bind_str))
  when Arel::Nodes::LessThanOrEqual
    condition.left.lteq(Arel.sql(bind_manager.next_bind_str))
  when Arel::Nodes::GreaterThan
    condition.left.gt(Arel.sql(bind_manager.next_bind_str))
  when Arel::Nodes::GreaterThanOrEqual
    condition.left.gteq(Arel.sql(bind_manager.next_bind_str))
  when Arel::Nodes::NamedFunction
    redact_named_function(condition, bind_manager)
  else
    raise ArgumentError, "Unsupported Arel node type for Redactor: #{condition.class}"
  end
end

.redact_named_function(condition, bind_manager) ⇒ Object 



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# File 'lib/click_house/client/redactor.rb', line 54

def self.redact_named_function(condition, bind_manager)
  redacted_condition =
    Arel::Nodes::NamedFunction.new(condition.name, condition.expressions.dup)

  case redacted_condition.name
  when 'startsWith'
    redacted_condition.expressions[1] = Arel.sql(bind_manager.next_bind_str)
  else
    redacted_condition.expressions = redacted_condition.expressions.map { Arel.sql(bind_manager.next_bind_str) }
  end

  redacted_condition
end