Scraper process callback examples

README.md

Run each script and kill it (control + c). When scraper is required, we cannot hook into process.on callbacks

test-process-no-scraperjs.js

/**
 * If scraper is not included, callback gets called
 */
process.on('SIGINT', function(){
    console.log('Hello I get called');
    process.exit(1);
});

setTimeout(function(){}, 19000); // keep alive

test-process-with-scraperjs.js

/**
 * If scraper is included before process.on calls, the callbacks never get called
 */
var scraperjs = require('scraperjs');

process.on('SIGINT', function(){
    console.log('Hello I never get called');
    process.exit(1);
});

setTimeout(function(){}, 19000); // keep alive

test-timeouts-no-scraperjs.js

/**
 * If scraper is not included, callbacks are all called
 */

function close() {
    console.log('Received SIGINT...emitting cleanup\n');
    process.emit('cleanup');

    setTimeout(function() {
        console.log('>>>>>>>>>> Exiting \n');
        process.exit(1);
    }, 1000);
}
process.on('SIGINT', close);

process.on('cleanup', function(){
    console.log("<<< CLEANING >>>");
    setTimeout(function(){
        console.log('<<< TIMEOUT CALLED >>>');
    }, 100);
});

setTimeout(function(){}, 19000); // keep alive

test-timeouts-with-scraperjs.js

/**
 * If scraperjs is included after everything is set up, the timeout in process.on('cleanup')
 * is never called.
 */

function close() {
    console.log('Received SIGINT...emitting cleanup\n');
    process.emit('cleanup');

    setTimeout(function() {
        console.log('>>>>>>>>>> Exiting \n');
        process.exit(1);
    }, 1000);
}
process.on('SIGINT', close);

process.on('cleanup', function(){
    console.log("<<< CLEANING >>>");
    setTimeout(function(){
        console.log('<<< THIS IS NEVER CALLED >>>');
    }, 100);
});

setTimeout(function(){}, 19000); // keep alive

// If we import it down here, the initial process signal is caught, but timeout
// callbacks never get called
var scraperjs = require('scraperjs');