like-gold•4y ago

custom CheerioCrawler User-Agent?

hi, could anyone show me an example of CheerioCrawler User-Agent? I had tried preNavigationHooks but got a stranger error

  preNavigationHooks: [
    function customUserAgent(_ctx, opts = {}) {
      opts.headers = opts.headers || {};
      opts.useHeaderGenerator = true;
      opts.headerGeneratorOptions = {
        browsers: [ 'chrome', 'safari' ],
        devices: [ 'mobile' ],
        operatingSystems: [ 'android', 'ios' ],
      };
    },
  ]

  preNavigationHooks: [
    function customUserAgent(_ctx, opts = {}) {
      opts.headers = opts.headers || {};
      opts.useHeaderGenerator = true;
      opts.headerGeneratorOptions = {
        browsers: [ 'chrome', 'safari' ],
        devices: [ 'mobile' ],
        operatingSystems: [ 'android', 'ios' ],
      };
    },
  ]

but got error: RequestError: No headers based on this input can be generated. I had tried use this options with header-generator then it works, but don't work with CheerioCrawler hooks

7 Replies

rival-black•4y ago

How about using the search function in the forum? https://discord.com/channels/801163717915574323/1022116407053394011

Alexey Udovydchenko•4y ago

Like this:

        preNavigationHooks: [
            (crawlingContext) => {
                const { request } = crawlingContext;
                    request.headers = webClientHeaders;
            },
        ],

        preNavigationHooks: [
            (crawlingContext) => {
                const { request } = crawlingContext;
                    request.headers = webClientHeaders;
            },
        ],

like-goldOP•4y ago

thanks, I had searched before. My Question is a little differnce.
1. I want to use useHeaderGenerator so the user-agent will change each crawle to avoid block 2. it seems that is a bug of headerGeneratorOptions ?

absent-sapphire•4y ago

You can do this with fingerprint-suite (https://github.com/apify/fingerprint-suite/). Like this

    // https://crawlee.dev/api/cheerio-crawler/interface/CheerioCrawlerOptions#preNavigationHooks
    preNavigationHooks: [
        async (_, gotOptions) => {
            // https://github.com/apify/fingerprint-suite/blob/master/docs/guides/fingerprint-generator.md
            let fingerprintGenerator = new FingerprintGenerator({
                browsers: ['chrome', 'edge', 'firefox', 'safari'],
                devices: [ 'desktop' ],
                operatingSystems: [ 'windows' ]
            });
            let { headers } = fingerprintGenerator.getFingerprint();
            gotOptions.headers = headers
        },
    ]

    // https://crawlee.dev/api/cheerio-crawler/interface/CheerioCrawlerOptions#preNavigationHooks
    preNavigationHooks: [
        async (_, gotOptions) => {
            // https://github.com/apify/fingerprint-suite/blob/master/docs/guides/fingerprint-generator.md
            let fingerprintGenerator = new FingerprintGenerator({
                browsers: ['chrome', 'edge', 'firefox', 'safari'],
                devices: [ 'desktop' ],
                operatingSystems: [ 'windows' ]
            });
            let { headers } = fingerprintGenerator.getFingerprint();
            gotOptions.headers = headers
        },
    ]

Attached POC: cheerio_crawler with this.

cheerio_crawler.ts

MEE6•4y ago

@LeMoussel just advanced to level 2! Thanks for your contributions! 🎉

like-goldOP•4y ago

@LeMoussel thanks, I had use header-generator and it works. But my question is why built-in headerGeneratorOptions fail, did I miss something?

Lukas Krivka•4y ago

@petrpatek. Pls check here why the header generator fails to generate

custom CheerioCrawler User-Agent?

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