lib/execution/starter.js

// Copyright (c) 2019, Compiler Explorer Team
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
//     * Redistributions of source code must retain the above copyright notice,
//       this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in the
//       documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
"use strict";

const
    AWS = require('aws-sdk'),
    uuidv1 = require('uuid/v1'),
    logger = require('../logger').logger,
    path = require('path');

class ExecutionStarter {
    constructor(region, queueName, executableCache) {
        this.sqs = new AWS.SQS({region: region});
        this.execRequestsUrl = false;
        this.execResponseBucket = executableCache;

        this.create(queueName).then(url => {
            this.execRequestsUrl = url;
        });
    }

    getResponse(uniqueId) {
        const initialWaitMs = 75;
        const backOffRatio = 1.5;
        const maxCheckEveryMs = 2000;
        const timeoutAfterSecs = 60;
        const timeoutAt = Date.now() + timeoutAfterSecs * 1000;

        const retry = (resolve, reject, checkAfterMs) => {
            logger.debug("reading from", uniqueId, "after", checkAfterMs);
            setTimeout(() => {
                const resubmit = () => {
                    if (Date.now() > timeoutAt) {
                        return reject("Timed out");
                    }
                    retry(resolve, reject, Math.min(maxCheckEveryMs, checkAfterMs * backOffRatio) | 0);
                };

                this.execResponseBucket.get(uniqueId)
                    .then(result => {
                        if (result.hit) {
                            const resultObj = JSON.parse(result.data);
                            logger.debug("response", JSON.stringify(resultObj));
                            resolve(resultObj);
                        } else {
                            resubmit();
                        }
                    })
                    .catch(() => {
                        logger.debug("unable to get response");
                        resubmit();
                    });
            }, checkAfterMs);
        };

        return new Promise((resolve, reject) => retry(resolve, reject, initialWaitMs));
    }

    static getResponseKey(hashedKey) {
        return hashedKey + '_' + uuidv1();
    }

    execute(hashedKey, buildResult, execParams) {
        const executable = path.relative(buildResult.dirPath, buildResult.executableFilename);
        return new Promise((resolve, reject) => {
            const uniqueId = ExecutionStarter.getResponseKey(hashedKey);

            const params = {
                MessageAttributes: {
                    hashedKey: {
                        DataType: "String",
                        StringValue: hashedKey
                    },
                    executable: {
                        DataType: "String",
                        StringValue: executable
                    },
                    execParams: {
                        DataType: "String",
                        StringValue: JSON.stringify(execParams)
                    }
                },
                MessageBody: uniqueId,
                QueueUrl: this.execRequestsUrl
            };

            this.sqs.sendMessage(params, (err) => {
                if (err) {
                    logger.error(err);
                    reject(err);
                } else {
                    this.getResponse(uniqueId)
                        .then(response => resolve(response))
                        .catch(failure => reject(failure));
                }
            });
        });
    }

    create(name) {
        return new Promise((resolve, reject) => {
            const params = {
                QueueName: name,
                Attributes: {
                    DelaySeconds: '0',
                    MessageRetentionPeriod: '86400'
                }
            };

            this.sqs.createQueue(params, function (err, data) {
                if (err) {
                    reject(err);
                } else {
                    resolve(data.QueueUrl);
                }
            });
        });
    }
}

module.exports = {
    ExecutionStarter
};