javascript - 无法使用异步 waterfall 运行 parse-csv 函数

Question

我正在尝试请求一个 url，从中获取一个 csv 文件，然后将该 csv 转换为 json。我正在使用 request , async和 csv-parser

我有这个代码:

var fs = require('fs'),
    async = require('async'),
    request = require('request'),
    csv = require('csv-parser'),
    fileUrl = 'http://forever.codeforamerica.org/fellowship-2015-tech-interview/Violations-2012.csv'

var getData = function(cb){
    request(fileUrl, function(err, response, body){
        (err) ? cb(err) : cb(null, body);
    })
};

var parseCsv = function(csvData, cb){
    var violations = [];
    fs.createReadStream(csvData)
        .pipe(csv())
        .on('data', function(violation){
            violations.push(violation)
        })
        .on('end', function(){
            cb(null, violations)
        })
}

// run the functions
async.waterfall([
    getData,
    parseCsv
], function(err, results){
    if (err) return err;

    console.log('this does not log')
})

我得到的文件很好，但每次它都会记录 csv 数据，而不是 json，无论我是什么 console.log

Answer 1

管道处理不正确，您可以将“请求”响应直接传递到管道中。

var fs = require('fs'),
    async = require('async'),
    request = require('request'),
    csv = require('csv-parser'),
    fileUrl = 'http://forever.codeforamerica.org/fellowship-2015-tech-interview/Violations-2012.csv';

var parseCsv = function(cb){
    var violations = [];
    request.get(fileUrl)
    .pipe(csv())
        .on('data', function(violation){
            violations.push(violation);
        })
        .on('end', function(){
            cb(null, violations);
        });
};

// run the functions
async.waterfall([
    parseCsv
], function(err, results){
    console.log(err, results);
});

输出:

{ violation_id: '225880', inspection_id: '289908', violation_category: 'Unsanitary Conditions', violation_date: '2012-10-17 00:00:00', violation_date_closed: '2012-11-08 00:00:00', violation_type: 'Unsanitary Floors or Walls' }, { violation_id: '225905', inspection_id: '289962', violation_category: 'Vegetation', violation_date: '2012-10-26 00:00:00', violation_date_closed: '2013-01-07 00:00:00', violation_type: 'Overgrown Vegetation' }, { violation_id: '224854', inspection_id: '288325'

PS:类似问题here