webcrawlerapi-js/README.md

JS client for WebcrawlerAPI

# JS client for WebcrawlerAPI

Official client for [WebcrawlerAPI](https://webcrawlerapi.com/). This SDK provides a robust and type-safe way to interact with WebcrawlerAPI's powerful web scraping capabilities, making it easy to extract structured data from any website.

WebcrawlerAPI allows you to extract data from any website with just a simple API call. The service handles all the complexities of web scraping, including JavaScript rendering, proxy rotation, and rate limiting, so you can focus on using the data.

## Preparation
1. Register to [dashboard|https://dash.webcrawlerapi.com/].
2. Get an [Access Key](https://dash.webcrawlerapi.com/access).

Our dashboard provides comprehensive analytics and monitoring tools to help you track your API usage and optimize your scraping operations.

## Installation
Install WebcrawlerAPI js package:

`npm i webcrawlerapi-js`

The package is regularly updated with new features and improvements to ensure the best possible scraping experience.

## JavaScript Examples

### Synchronous Job
In this mode, the promise will be resolved when all data is ready. Synchronous jobs are perfect for quick scraping tasks where you need immediate results and don't want to handle polling logic. However, for long running jobs we recommend to use async crawling or the webhook.

```javascript
import webcrawlerapi from "webcrawlerapi-js"

async function main() {
    const client = new WebcrawlerClient("YOUR API ACCESS KEY HERE")

    try {
        const crawlJob = await client.crawl({
            "items_limit": 10,
            "url": "https://books.toscrape.com/",
            "scrape_type": "markdown"
        })
        
        // Get job details
        const job = await client.getJob(crawlJob.id);
        console.log("Job status:", job.status);

        // Output item content
        for (const item of job.job_items) {
            const content = await item.getContent()
            console.log("---- Title: " + item.title + "----")
            console.log(content.slice(0, 100))
        }
    } catch (error) {
        if (error instanceof webcrawlerapi.WebcrawlerApiError) {
            console.error("Webcrawler error:", error.message)
        }
        console.error(error)
    }
}

main().catch(console.error)
```

### Asynchronous Job
In this mode, you get a job ID immediately and can poll for results. Asynchronous jobs are ideal for large-scale scraping operations where you want to process data in batches or handle long-running tasks efficiently.

```javascript
import webcrawlerapi from "webcrawlerapi-js"

async function main() {
    const client = new WebcrawlerClient("YOUR API ACCESS KEY HERE")

    try {
        try {
        const jobWithId = await client.crawlAsync({
            "items_limit": 10,
            "url": "https://books.toscrape.com/",
            "scrape_type": "markdown"
        })

        // Poll for job completion
        const jobId = jobWithId.id
        let asyncJob = await client.getJob(jobId)

        // Check job status
        console.log("Job id:", asyncJob.id)
        console.log("Dashboard link:", `https://dash.webcrawlerapi.com/jobs/job/${asyncJob.id}`)

        //wait until job is done
        while (asyncJob.status !== "done") {
            await new Promise(resolve => setTimeout(resolve, 1000));
            asyncJob = await client.getJob(jobId)
        }

        // Once complete, access results
        if (asyncJob.status === "done") {
            for (const item of asyncJob.job_items) {
                const content = await item.getContent()
                console.log(content.slice(0, 100))
            }
        }
    } catch (error) {
        if (error instanceof webcrawlerapi.WebcrawlerApiError) {
            console.error("Webcrawler error:", error.message)
        }
        console.error(error)
        return
    }
}

main().catch(console.error)
```

## TypeScript Usage

The SDK provides full TypeScript support with type safety and error handling. Our TypeScript integration ensures you catch potential issues at compile-time and provides excellent IDE support with autocompletion and inline documentation.

```typescript
import {WebcrawlerClient, WebcrawlerApiError} from "webcrawlerapi-js";

async function main() {
    const client = new WebcrawlerClient("YOUR_API_KEY")

    try {
        // Basic crawl with markdown
        const syncJob = await client.crawl({
            "items_limit": 10,
            "url": "https://books.toscrape.com/",
            "scrape_type": "markdown",
        }
    )
        // Type-safe status check
        for (const item of syncJob.job_items) {
            const content = await item.getContent()
            console.log(content.slice(0,100))
        }
    } catch (error) {
        if (error instanceof WebcrawlerApiError) {
            console.error("API Error:", error.errorCode, error.message)
        }
        console.log(error)
    }
}

main().catch(console.error)
```

## Response Structure

Example of a job response. The response structure is carefully designed to provide comprehensive information about your scraping job, including detailed status updates, timing information, and resource usage metrics.

```js
{
  id: '49c4942b-b7d9-4d62-94b5-b54a3016ac51',
  url: 'https://stripe.com/',
  scrape_type: 'markdown',
  whitelist_regexp: '',
  blacklist_regexp: '',
  allow_subdomains: false,
  items_limit: 10,
  created_at: '2024-12-28T21:36:04.417Z',
  finished_at: null,
  updated_at: '2024-12-28T21:36:04.383Z',
  webhook_url: '',
  status: 'in_progress',
  job_items: [
    {
      id: 'f26cefe1-09d1-4d4c-8b74-b65e075e230d',
      job_id: '49c4942a-b7d9-4d62-94b5-b54a3016ac51',
      original_url: 'https://stripe.com/',
      page_status_code: 0,
      status: 'new',
      title: '',
      last_error: '',
      error_code: '',
      created_at: '2024-12-28T21:36:04.468Z',
      updated_at: '2024-12-28T21:36:04.435Z',
      cost: 0,
      referred_url: ''
    }
  ],
  recommended_pull_delay_ms: 5000
}
```