s202226701001/sever-test/node_modules/firebase-admin/lib/remote-config/condition-evaluator-internal.js

/*! firebase-admin v12.1.1 */
/*!
 * Copyright 2024 Google Inc.
 *
 * 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.
 */
'use strict';
Object.defineProperty(exports, "__esModule", { value: true });
exports.ConditionEvaluator = void 0;
const remote_config_api_1 = require("./remote-config-api");
const farmhash = require("farmhash");
const long = require("long");
/**
 * Encapsulates condition evaluation logic to simplify organization and
 * facilitate testing.
 *
 * @internal
 */
class ConditionEvaluator {
    evaluateConditions(namedConditions, context) {
        // The order of the conditions is significant.
        // A JS Map preserves the order of insertion ("Iteration happens in insertion order"
        // - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#description).
        const evaluatedConditions = new Map();
        for (const namedCondition of namedConditions) {
            evaluatedConditions.set(namedCondition.name, this.evaluateCondition(namedCondition.condition, context));
        }
        return evaluatedConditions;
    }
    evaluateCondition(condition, context, nestingLevel = 0) {
        if (nestingLevel >= ConditionEvaluator.MAX_CONDITION_RECURSION_DEPTH) {
            // TODO: add logging once we have a wrapped logger.
            return false;
        }
        if (condition.orCondition) {
            return this.evaluateOrCondition(condition.orCondition, context, nestingLevel + 1);
        }
        if (condition.andCondition) {
            return this.evaluateAndCondition(condition.andCondition, context, nestingLevel + 1);
        }
        if (condition.true) {
            return true;
        }
        if (condition.false) {
            return false;
        }
        if (condition.percent) {
            return this.evaluatePercentCondition(condition.percent, context);
        }
        // TODO: add logging once we have a wrapped logger.
        return false;
    }
    evaluateOrCondition(orCondition, context, nestingLevel) {
        const subConditions = orCondition.conditions || [];
        for (const subCondition of subConditions) {
            // Recursive call.
            const result = this.evaluateCondition(subCondition, context, nestingLevel + 1);
            // Short-circuit the evaluation result for true.
            if (result) {
                return result;
            }
        }
        return false;
    }
    evaluateAndCondition(andCondition, context, nestingLevel) {
        const subConditions = andCondition.conditions || [];
        for (const subCondition of subConditions) {
            // Recursive call.
            const result = this.evaluateCondition(subCondition, context, nestingLevel + 1);
            // Short-circuit the evaluation result for false.
            if (!result) {
                return result;
            }
        }
        return true;
    }
    evaluatePercentCondition(percentCondition, context) {
        if (!context.randomizationId) {
            // TODO: add logging once we have a wrapped logger.
            return false;
        }
        // This is the entry point for processing percent condition data from the response.
        // We're not using a proto library, so we can't assume undefined fields have
        // default values.
        const { seed, percentOperator, microPercent, microPercentRange } = percentCondition;
        if (!percentOperator) {
            // TODO: add logging once we have a wrapped logger.
            return false;
        }
        const normalizedMicroPercent = microPercent || 0;
        const normalizedMicroPercentUpperBound = microPercentRange?.microPercentUpperBound || 0;
        const normalizedMicroPercentLowerBound = microPercentRange?.microPercentLowerBound || 0;
        const seedPrefix = seed && seed.length > 0 ? `${seed}.` : '';
        const stringToHash = `${seedPrefix}${context.randomizationId}`;
        // Using a 64-bit long for consistency with the Remote Config fetch endpoint.
        let hash64 = long.fromString(farmhash.fingerprint64(stringToHash));
        // Negate the hash if its value is less than 0. We handle this manually because the
        // Long library doesn't provided an absolute value method.
        if (hash64.lt(0)) {
            hash64 = hash64.negate();
        }
        const instanceMicroPercentile = hash64.mod(100 * 1000000);
        switch (percentOperator) {
            case remote_config_api_1.PercentConditionOperator.LESS_OR_EQUAL:
                return instanceMicroPercentile.lte(normalizedMicroPercent);
            case remote_config_api_1.PercentConditionOperator.GREATER_THAN:
                return instanceMicroPercentile.gt(normalizedMicroPercent);
            case remote_config_api_1.PercentConditionOperator.BETWEEN:
                return instanceMicroPercentile.gt(normalizedMicroPercentLowerBound)
                    && instanceMicroPercentile.lte(normalizedMicroPercentUpperBound);
            case remote_config_api_1.PercentConditionOperator.UNKNOWN:
            default:
                break;
        }
        // TODO: add logging once we have a wrapped logger.
        return false;
    }
}
exports.ConditionEvaluator = ConditionEvaluator;
ConditionEvaluator.MAX_CONDITION_RECURSION_DEPTH = 10;