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<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Diggernaut: Documentation for Meta-Language | Other Commands | Headers</title>
<meta name="description" content="How to get and use data from server response headers.">
<meta name="keywords" content="Diggernaut, scraping, web scraping, scraper, web scraper, meta-language, make scraper, scraper for websites, learning to scrape, data acquisition, create scraper, online scraper, content scraper, scraper for shop, scraper for classifieds, coding scraper, headers">
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<h1>Other Commands</h1>
<div>
<h2>Headers</h2>
<p class="flow-text">
Sometimes the server returns important information with the response headers. For example, it can be a special token, code or service information
which should be used in subsequent requests or scraping logic. The <span class = "hlt2">header_get</span> command is used to read the headers.
As an operand, it takes the name of the header and reads the contents of the header to the register, so this command can only be used in a block context.
</p>
<p class="flow-text">
Usage example:
</p>
<pre class="language-yaml">
<code class="language-yaml"># READ HEADER WITH NAME `RateLimit-Remaining` and check if we exceed limit for number of connections
- find:
path: html
do:
- header_get: RateLimit-Remaining
- if:
lt: 5
type: int
do:
- sleep: 86400
</code></pre>
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