When you assign the page results from the scrape-it npm to a variable, it will return a Promise with the status of "pending."

Question

When you assign the page results from the scrape-it npm to a variable, it will return a Promise with the status of "pending."

I recently downloaded scrape-it from NPM as a dependency and I'm trying to store the results in a variable instead of using a callback function. When I run the code snippet provided in the scrape-it documentation:

var myVar = scrapeIt("http://ionicabizau.net", {
    title: ".header h1"
  , desc: ".header h2"
  , avatar: {
        selector: ".header img"
      , attr: "src"
    }
}).then(page => {
    return page;
});

console.log(myVar);

I receive the output: Promise { <pending> }. I've also attempted to use 'await' before calling the scrapeIt() function, but this resulted in a 'Unexpected identifier' syntax error.

Oddly enough, when I tried this code on the RunKit + npm platform, it worked perfectly fine. However, executing it locally on my machine throws errors. I've double-checked all dependencies and even reinstalled the package, yet I can't figure out what's going wrong. Any help would be greatly appreciated.

While this issue does relate to the asynchronous nature of JavaScript, the main focus is on improving my understanding of working with promises.

javascript npm promise

Answer 1

Answer №1

The method scrapeIt operates asynchronously because of the async nature of the request module.

scrapeIt.scrapeHTML is synchronous, but it requires the HTML to be provided as a string.

Therefore, if you are able to obtain the HTML from any source, you can perform a similar action to what was demonstrated:

var result = scrapeIt.scrapeHTML("<p>Goodbye</p>", {
    message: "p"
});
console.log(result);
// { message: "p" }

An asynchronous task is something that requires waiting (e.g., downloading the HTML content of a page—this process takes time). This is why methods like callbacks and promises exist.

scrapeIt("http://example.com", {
    title: ".header h1"
  , description: ".header h2"
  , image: {
        selector: ".header img"
      , attribute: "src"
    }
}).then(output => {
   // Utilize the output data once it's available
   // Once the webpage has been fetched and parsed,
   // this function will be executed
   console.log(output)

   // Perform actions with the output data here
});

// The webpage has not yet been downloaded at this stage.

Answer 2

The method scrapeIt operates asynchronously because of the async nature of the request module.

scrapeIt.scrapeHTML is synchronous, but it requires the HTML to be provided as a string.

Therefore, if you are able to obtain the HTML from any source, you can perform a similar action to what was demonstrated:

var result = scrapeIt.scrapeHTML("<p>Goodbye</p>", {
    message: "p"
});
console.log(result);
// { message: "p" }

An asynchronous task is something that requires waiting (e.g., downloading the HTML content of a page—this process takes time). This is why methods like callbacks and promises exist.

scrapeIt("http://example.com", {
    title: ".header h1"
  , description: ".header h2"
  , image: {
        selector: ".header img"
      , attribute: "src"
    }
}).then(output => {
   // Utilize the output data once it's available
   // Once the webpage has been fetched and parsed,
   // this function will be executed
   console.log(output)

   // Perform actions with the output data here
});

// The webpage has not yet been downloaded at this stage.

When you assign the page results from the scrape-it npm to a variable, it will return a Promise with the status of "pending."

Answer №1

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