Product search using PA-API v5

paapi5search.js

// paapi5search.js - Product search using PA-API v5
//   by takehikom

// npm install paapi5-nodejs-sdk
// npm install optparse
// npm install bitly

// node search.js 'Harry Potter'
// node search.js 9784791628889
// node search.js -t 9784393376034 -j
// node search.js -t 9784623071326 -j
// node search.js -j -t 978-4-7741-5394-0
// node search.js -j -b -t 978-4-7741-5394-0

// 4.0から大きく変わった「PA-API v5.0（Amazon API）」の使い方！ | HPcode
// https://haniwaman.com/pa-api-5/
// JavascriptでオプションのパースをするOptparse-js
// https://ota42y.com/blog/2014/08/26/optparse/

// ~/.amazonrcを読み出してaccessKey, secretKey, PartnerTagを獲得する
const find_keys = () => {
    var hash = {};
    const path = require('path');
    const userHome = process.env['HOME'];
    const rcFile = path.join(userHome, '.amazonrc');

    try {
        const fs = require('fs');
        const text = fs.readFileSync(rcFile, 'utf8');
        const lines = text.toString().split('\n');
        for (var line0 of lines) {
            const line = line0.replace(/ /g, '');
            if (line.match(/^#/)) continue;
            var m;
            if ((m = line.match(/^secret_key_id=(.+)/)) != null) {
                const v = m[1].replace(/^['"]|['"]$/g, '')
                // console.log('secretKey = ' + v);
                hash['secretKey'] = v
            } else if ((m = line.match(/^key_id=(.+)/)) != null) {
                const v = m[1].replace(/^['"]|['"]$/g, '')
                // console.log('accessKey = ' + v);
                hash['accessKey'] = v;
            } else if ((m = line.match(/^associate=(.+)/)) != null) {
                const v = m[1].replace(/^['"]|['"]$/g, '')
                // console.log('PartnerTag = ' + v);
                hash['PartnerTag'] = v
            } else if ((m = line.match(/^bitly[^=]*=(.+)/)) != null) {
                // https://bitly.comにサインアップまたはログインし，
                // 右上のv，Profile Settings，Generic Access Token，
                // パスワード認証でアクセストークンが生成されるので，
                // ~/.amazonrcに「bitly = 'アクセストークン'」を書く
                const v = m[1].replace(/^['"]|['"]$/g, '')
                // console.log('Bitly Access Token = ' + v);
                hash['Bitly'] = v
            }
        }
    } catch (ex) {
        return hash;
    }

    return hash;
};

const keys = find_keys();
// 読み出せなければ終了する
if (!keys['accessKey'] || !keys['secretKey'] || !keys['PartnerTag']) {
    console.log('Please prepare ~/.amazonrc');
    process.exit(0);
}

// Bitlyにアクセスして短縮URLを作成する
const shortenURL = async (uri) => {
    const { BitlyClient } = require('bitly');
    const bitly = new BitlyClient(keys['Bitly'], {});
    let result;
    try {
        result = await bitly.shorten(uri);
        return result.link;
    } catch(e) {
        return null;
    }
}

// コマンドライン解析
const optSwitches = [
    ['-t', '--term TERM', 'Search term (product name or ISBN/ASIN)'],
    ['-m', '--max NUMBER', 'Max number of items'],
    ['-j', '--json', 'Print query result'],
    ['-S', '--no-summary', 'Suppress summary'],
    ['-b', '--bitly', 'URL shortening'],
    ['-d', '--debug', 'Debug mode']
];
const optparse = require('optparse');
var parameter = {};
var parser = new optparse.OptionParser(optSwitches);
parser.on('term', (opt, value) => { parameter['term'] = value; });
parser.on('max', (opt, value) => { parameter['max'] = value; });
parser.on('json', () => { parameter['json'] = true; });
parser.on('no-summary', () => { parameter['nosum'] = true; });
parser.on('bitly', () => { parameter['bitly'] = true; });
parser.on('debug', () => { parameter['debug'] = true; });
const parserResult = parser.parse(process.argv);
const debug = parameter['debug'];
if (debug) {
    console.log('Parameter:');
    console.log(parameter);
    console.log('Non-parsed Parameter:');
    console.log(parserResult);
    // console.log('Original Parameter:');
    // console.log(process.argv);
    // process.exit(0);
}

// 引数がなければ使用法を出力して終了する
if (!parameter['term']) {
    if (parserResult.length <= 2) {
        console.log('Usage: search.js [...]');
        console.log(optSwitches.map((a) => {
            return '    ' + [a[0],
                             (a[1] + ' '.repeat(12)).slice(0, 12),
                             a[2]].join('  ');
        }).join("\n"))
        process.exit(0);
    }
    parameter['term'] = parserResult[2];
}

const PAAPIv1 = require('paapi5-nodejs-sdk');
var defaultClient = PAAPIv1.ApiClient.instance;

// Specify your credentials here. These are used to create and sign the request.
defaultClient.accessKey = keys['accessKey'];
defaultClient.secretKey = keys['secretKey'];

/**
 * Specify Host and Region to which you want to send the request to.
 * For more details refer:
 * https://webservices.amazon.com/paapi5/documentation/common-request-parameters.html#host-and-region
 */
defaultClient.host = 'webservices.amazon.co.jp';
defaultClient.region = 'us-west-2';

var api = new PAAPIv1.DefaultApi();

/**
 * The following is a sample request for SearchItems operation.
 * For more information on Product Advertising API 5.0 Operations,
 * refer: https://webservices.amazon.com/paapi5/documentation/operations.html
 */
var siReq = new PAAPIv1.SearchItemsRequest();

/** Enter your partner tag (store/tracking id) and partner type */
siReq['PartnerTag'] = keys['PartnerTag'];
siReq['PartnerType'] = 'Associates';

// Specify search keywords
siReq['Keywords'] = parameter['term'];
// ISBNと推測される場合にはハイフンなどを取り除く
if (parameter['term'].match(/^[-_ \d]+[\dxX]/)) {
    siReq['Keywords'] = parameter['term'].replace(/[-_ ]/g, '');
}

/**
 * Specify the category in which search request is to be made.
 * For more details, refer:
 * https://webservices.amazon.com/paapi5/documentation/use-cases/organization-of-items-on-amazon/search-index.html
 */
siReq['SearchIndex'] = 'All';

// Specify the number of items to be returned in search result
siReq['ItemCount'] = parameter['max'] || 1;

/**
 * Choose resources you want from SearchItemsResource enum
 * For more details, refer: https://webservices.amazon.com/paapi5/documentation/search-items.html#resources-parameter
 */
siReq['Resources'] = [
    'ItemInfo.ContentInfo',
    'ItemInfo.ByLineInfo',
    'ItemInfo.Classifications',
    'ItemInfo.ExternalIds',
    'ItemInfo.Title',
    'Offers.Listings.Price'
];

// オブジェクトobjとプロパティ（任意個のドットを含む）propについて
// obj.propがあればその値を，なければundefinedを返す
const o = (obj, prop) => {
    const props = prop.split('.');
    var obj2 = obj;
    for (var i = 0; i < props.length; i++) {
        if (typeof (obj2) == 'object' && props[i] in obj2) {
            obj2 = obj2[props[i]];
        } else if (typeof (obj2) == 'object'
                   && props[i].match(/^\d+$/)
                   && props[Number(i)] in obj2) {
            obj2 = obj2[props[Number(i)]];
        } else {
            return undefined;
        }
    }
    return obj2;
};

// 呼び出し時のエラーの出力（キーワードに合致する商品がない場合など）
const printErrorByCalling = (error) => {
    console.log('Error calling PA-API 5.0!');
    const jerror = JSON.stringify(error, null, 1);
    console.log('Printing Full Error Object:\n' + jerror);
    console.log('Status Code: ' + error['status']);
    if (error['response'] !== undefined
        && error['response']['text'] !== undefined) {
        const jerror = JSON.stringify(error['response']['text'], null, 1);
        console.log('Error Object: ' + jerror);
    }
};

// SearchItemsResponse関連のエラーの出力
const printErrorWithSearchItemsResponse = (searchItemsResponseErrors) => {
    console.log('Errors:');
    const jerror = JSON.stringify(searchItemsResponseErrors, null, 1);
    console.log('Complete Error Response: ' + jerror);
    console.log('Printing 1st Error:');
    var error_0 = searchItemsResponseErrors[0];
    console.log('Error Code: ' + error_0['Code']);
    console.log('Error Message: ' + error_0['Message']);
};

// 1件の商品情報の出力
const print_item_summary = async (item) => {
    if (!item) return;

    /*
      item['ASIN']: ASIN(文字列)
      item['ItemInfo']['ByLineInfo']['Contributors']: 著者など(配列)
      item['ItemInfo']['ByLineInfo']['Manufacturer']['DisplayValue']: 出版社名(文字列)
      item['ItemInfo']['Classifications']['Binding']['DisplayValue']: 形態(文字列)
      item['ItemInfo']['ExternalIds']['EANs']['DisplayValues']: EAN(配列)
      item['ItemInfo']['ExternalIds']['ISBNs']['DisplayValues']: 10桁ISBN(配列)
      item['ItemInfo']['ContentInfo']['PublicationDate']['DisplayValue']: 出版年月日(文字列)
      item['Offers']['Listings'][0]['Price']['DisplayAmount']: 価格(文字列)
    */
    const asin = o(item, 'ASIN');
    const isbn = o(item, 'ItemInfo.ExternalIds.EANs.DisplayValues.0');
    const url1 = o(item, 'DetailPageURL');
    const url2 = url1 ? url1.replace(/\?.*$/, '') : undefined;
    const title = o(item, 'ItemInfo.Title.DisplayValue');
    const price = o(item, 'Offers.Listings.0.Price.DisplayAmount');
    const manu = o(item, 'ItemInfo.ByLineInfo.Manufacturer.DisplayValue');
    const dateString = o(item, 'ItemInfo.ContentInfo.PublicationDate.DisplayValue');
    const dateObj = dateString ? new Date(dateString) : undefined;
    const year = dateObj ? dateObj.getFullYear() : undefined;
    const contribs = o(item, 'ItemInfo.ByLineInfo.Contributors');
    const author = Array.isArray(contribs) ?
          contribs.map(x => {
              var name = x['Name'];
              const role = x['Role'];
              if (x['Locale'] == 'ja_JP') name = name.replace(/ /g, '');
              return name + (role !== undefined && role != '著' ? `(${x['Role']})` : '');
          }).join(', ') : undefined;
    const hn = isbn ? `[isbn:${isbn}]` : `[asin:${asin}]`;
    const biblio = `${author}: ${title}, ${manu} (${year}). ${hn}`;

    if (asin) console.log('<ASIN> ' + asin);
    if (isbn) console.log('<ISBN> ' + isbn);
    if (url1) console.log('<Detail Page URL> ' + url1);
    if (url2) console.log('<Simple URL> ' + url2);

    if (parameter['bitly'] && keys['Bitly'] && url2) {
        const url3 = await shortenURL(url2);
        console.log('<Shortened URL> ' + url3);
    }

    if (title) console.log('<Title> ' + title);
    if (author) console.log('<Author> ' + author);
    if (manu) console.log('<Manufacturer> ' + manu);
    if (dateString) console.log('<Publication Date> ' + dateString);
    if (price) console.log('<Buying Price> ' + price);
    console.log(biblio);
};

// api.searchItemsのコールバック関数
const callback = function (error, data, response) {
    if (error) {
        printErrorByCalling(error);
        return;
    }

    if (debug) console.log('API called successfully.');
    var siResp = PAAPIv1.SearchItemsResponse.constructFromObject(data);
    if (parameter['json']) {
        const jresp = JSON.stringify(siResp, null, 1);
        if (debug) console.log('Complete Response:');
        console.log(jresp);
    }

    if (!parameter['nosum']
        && siResp['SearchResult'] !== undefined) {
        // const count = o(siResp, 'SearchResult.TotalResultCount') || 0;
        const items = siResp['SearchResult']['Items'];
        const count = items.length;
        if (debug) console.log('count = ' + count);
        for (var i = 0; i < count; i++) {
            if (debug) console.log(`Printing Information in SearchResult (${i + 1}):`);
            var item = items[i];
            print_item_summary(item);
            if (i < count - 1) console.log('');
        }
    }

    if (siResp['Errors'] !== undefined) {
        printErrorWithSearchItemsResponse(siResp['Errors']);
    }
};

try {
    api.searchItems(siReq, callback);
} catch (ex) {
    console.log('Exception: ' + ex);
}