diff options
Diffstat (limited to 'app/services/prometheus/proxy_variable_substitution_service.rb')
| -rw-r--r-- | app/services/prometheus/proxy_variable_substitution_service.rb | 155 |
1 files changed, 0 insertions, 155 deletions
diff --git a/app/services/prometheus/proxy_variable_substitution_service.rb b/app/services/prometheus/proxy_variable_substitution_service.rb deleted file mode 100644 index 846dfeb33ce..00000000000 --- a/app/services/prometheus/proxy_variable_substitution_service.rb +++ /dev/null @@ -1,155 +0,0 @@ -# frozen_string_literal: true - -module Prometheus - class ProxyVariableSubstitutionService < BaseService - include Stepable - - VARIABLE_INTERPOLATION_REGEX = / - {{ # Variable needs to be wrapped in these chars. - \s* # Allow whitespace before and after the variable name. - (?<variable> # Named capture. - \w+ # Match one or more word characters. - ) - \s* - }} - /x.freeze - - steps :validate_variables, - :add_params_to_result, - :substitute_params, - :substitute_variables - - # @param environment [Environment] - # @param params [Hash<Symbol,Any>] - # @param params - query [String] The Prometheus query string. - # @param params - start [String] (optional) A time string in the rfc3339 format. - # @param params - start_time [String] (optional) A time string in the rfc3339 format. - # @param params - end [String] (optional) A time string in the rfc3339 format. - # @param params - end_time [String] (optional) A time string in the rfc3339 format. - # @param params - variables [ActionController::Parameters] (optional) Variables with their values. - # The keys in the Hash should be the name of the variable. The value should be the value of the - # variable. Ex: `ActionController::Parameters.new(variable1: 'value 1', variable2: 'value 2').permit!` - # @return [Prometheus::ProxyVariableSubstitutionService] - # - # Example: - # Prometheus::ProxyVariableSubstitutionService.new(environment, { - # params: { - # start_time: '2020-07-03T06:08:36Z', - # end_time: '2020-07-03T14:08:52Z', - # query: 'up{instance="{{instance}}"}', - # variables: { instance: 'srv1' } - # } - # }) - def initialize(environment, params = {}) - @environment = environment - @params = params.deep_dup - end - - # @return - params [Hash<Symbol,Any>] Returns a Hash containing a params key which is - # similar to the `params` that is passed to the initialize method with 2 differences: - # 1. Variables in the query string are substituted with their values. - # If a variable present in the query string has no known value (values - # are obtained from the `variables` Hash in `params` or from - # `Gitlab::Prometheus::QueryVariables.call`), it will not be substituted. - # 2. `start` and `end` keys are added, with their values copied from `start_time` - # and `end_time`. - # - # Example output: - # - # { - # params: { - # start_time: '2020-07-03T06:08:36Z', - # start: '2020-07-03T06:08:36Z', - # end_time: '2020-07-03T14:08:52Z', - # end: '2020-07-03T14:08:52Z', - # query: 'up{instance="srv1"}', - # variables: { instance: 'srv1' } - # } - # } - def execute - execute_steps - end - - private - - def validate_variables(_result) - return success unless variables - - unless variables.is_a?(ActionController::Parameters) - return error(_('Optional parameter "variables" must be a Hash. Ex: variables[key1]=value1')) - end - - success - end - - def add_params_to_result(result) - result[:params] = params - - success(result) - end - - def substitute_params(result) - start_time = result[:params][:start_time] - end_time = result[:params][:end_time] - - result[:params][:start] = start_time if start_time - result[:params][:end] = end_time if end_time - - success(result) - end - - def substitute_variables(result) - return success(result) unless query(result) - - result[:params][:query] = gsub(query(result), full_context(result)) - - success(result) - end - - def gsub(string, context) - # Search for variables of the form `{{variable}}` in the string and replace - # them with their value. - string.gsub(VARIABLE_INTERPOLATION_REGEX) do |match| - # Replace with the value of the variable, or if there is no such variable, - # replace the invalid variable with itself. So, - # `up{instance="{{invalid_variable}}"}` will remain - # `up{instance="{{invalid_variable}}"}` after substitution. - context.fetch($~[:variable], match) - end - end - - def predefined_context(result) - Gitlab::Prometheus::QueryVariables.call( - @environment, - start_time: start_timestamp(result), - end_time: end_timestamp(result) - ).stringify_keys - end - - def full_context(result) - @full_context ||= predefined_context(result).reverse_merge(variables_hash) - end - - def variables - params[:variables] - end - - def variables_hash - variables.to_h - end - - def start_timestamp(result) - Time.rfc3339(result[:params][:start]) - rescue ArgumentError - end - - def end_timestamp(result) - Time.rfc3339(result[:params][:end]) - rescue ArgumentError - end - - def query(result) - result[:params][:query] - end - end -end |