@optimizely/optimizely-sdk/lib/core/optimizely_config/index.js

JavaScript SDK for Optimizely X Full Stack

/**
 * Copyright 2019-2020, Optimizely
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import { isFeatureExperiment } from '../project_config';

// Get Experiment Ids which are part of rollouts
function getRolloutExperimentIds(rollouts) {
  return (rollouts || []).reduce(function(experimentIds, rollout) {
    rollout.experiments.forEach(function(e) {
      experimentIds[e.id] = true;
    });
    return experimentIds;
  }, {});
}

// Gets Map of all experiments except rollouts
function getExperimentsMap(configObj) {
  var rolloutExperimentIds = getRolloutExperimentIds(configObj.rollouts);
  var featureVariablesMap = (configObj.featureFlags || []).reduce(function(resultMap, feature) {
    resultMap[feature.id] = feature.variables;
    return resultMap;
  }, {});
  return (configObj.experiments || []).reduce(function(experiments, experiment) {
    // skip experiments that are part of a rollout
    if (!rolloutExperimentIds[experiment.id]) {
      experiments[experiment.key] = {
        id: experiment.id,
        key: experiment.key,
        variationsMap: (experiment.variations || []).reduce(function(variations, variation) {
          variations[variation.key] = {
            id: variation.id,
            key: variation.key,
            variablesMap: getMergedVariablesMap(configObj, variation, experiment.id, featureVariablesMap),
          };
          if (isFeatureExperiment(configObj, experiment.id)) {
            variations[variation.key].featureEnabled = variation.featureEnabled;
          }
          return variations;
        }, {}),
      };
    }
    return experiments;
  }, {});
}

// Merges feature key and type from feature variables to variation variables.
function getMergedVariablesMap(configObj, variation, experimentId, featureVariablesMap) {
  var featureId = configObj.experimentFeatureMap[experimentId];
  var variablesObject = {};
  if (featureId) {
    var experimentFeatureVariables = featureVariablesMap[featureId];
    // Temporary variation variables map to get values to merge.
    var tempVariablesIdMap = (variation.variables || []).reduce(function(variablesMap, variable) {
      variablesMap[variable.id] = {
        id: variable.id,
        value: variable.value,
      };
      return variablesMap;
    }, {});
    variablesObject = (experimentFeatureVariables || []).reduce(function(variablesMap, featureVariable) {
      var variationVariable = tempVariablesIdMap[featureVariable.id];
      var variableValue =
        variation.featureEnabled && variationVariable ? variationVariable.value : featureVariable.defaultValue;
      variablesMap[featureVariable.key] = {
        id: featureVariable.id,
        key: featureVariable.key,
        type: featureVariable.type,
        value: variableValue,
      };
      return variablesMap;
    }, {});
  }
  return variablesObject;
}

// Gets map of all experiments
function getFeaturesMap(configObj, allExperiments) {
  return (configObj.featureFlags || []).reduce(function(features, feature) {
    features[feature.key] = {
      id: feature.id,
      key: feature.key,
      experimentsMap: (feature.experimentIds || []).reduce(function(experiments, experimentId) {
        var experimentKey = configObj.experimentIdMap[experimentId].key;
        experiments[experimentKey] = allExperiments[experimentKey];
        return experiments;
      }, {}),
      variablesMap: (feature.variables || []).reduce(function(variables, variable) {
        variables[variable.key] = {
          id: variable.id,
          key: variable.key,
          type: variable.type,
          value: variable.defaultValue,
        };
        return variables;
      }, {}),
    };
    return features;
  }, {});
}

/**
 * The OptimizelyConfig class
 * @param {Object} configObj
 * @param {string} datafile
 */
export function OptimizelyConfig(configObj, datafile) {
  this.experimentsMap = getExperimentsMap(configObj);
  this.featuresMap = getFeaturesMap(configObj, this.experimentsMap);
  this.revision = configObj.revision;
  this.__datafile = datafile;
}

/**
 * Get the datafile
 * @returns {string} JSON string representation of the datafile that was used to create the current config object
 */
OptimizelyConfig.prototype.getDatafile = function() {
  return this.__datafile;
}

export default {
  OptimizelyConfig: OptimizelyConfig
}