Using Smartproxy API in TypeScript

smartproxy.ts

export interface SerpScrapingResult {
  query: string;
  title: string;
  position: number;
  url: string;
}

function createRequestParams(apiKey: string, query: string): RequestInit {
  return {
    method: 'POST',
    body: JSON.stringify({
      target: 'google_search',
      query: query,
      parse: true,
      domain: 'co.jp',
      locale: 'ja',
      google_results_language: 'ja',
      geo: 'Japan',
      device_type: 'mobile',
      page_from: 1,
      num_pages: 20,
      google_nfpr: true,
      google_safe_search: false,
    }),
    headers: {
      'Content-Type': 'application/json',
      Authorization: `Basic ${apiKey}`,
    },
  };
}

function createUrl(url: string): string {
  const baseUrl = 'https://google.co.jp';

  if (url.startsWith('http://') || url.startsWith('https://')) {
    return url;
  }

  if (url.startsWith('/')) {
    return `${baseUrl}${url}`;
  } else {
    return `${baseUrl}/${url}`;
  }
}

function parseData(query: string, json: any): SerpScrapingResult[] {
  const results = json.results[0].content.results;
  const organics = results.organic;

  return organics?.map((organic: any) => {
    const pos = parseInt(organic.pos, 10);

    return {
      query,
      title: organic.title || '',
      position: isNaN(pos) ? null : pos,
      url: createUrl(organic.url),
    } as SerpScrapingResult;
  }) || [];
}

export async function fetchSerp(apiKey: string, query: string): Promise<SerpScrapingResult[]> {
  try {
    const url = 'https://scrape.smartproxy.com/v1/tasks';
    const params = createRequestParams(apiKey, query);
    const response = await fetch(url, params).then((response) => {
      if (!response.ok) {
        throw new Error(`Error on fetch ${url}: ${response.statusText}`);
      }

      return response as Response;
    });
    const json = await response.json();

    return parseData(query, json);
  } catch (error) {
    throw error;
  }
}