youtube-comment-scraper/README.md

Scraping comments from Youtube.

# Youtube comment scraper
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Scraping comments from Youtube.

## Installation
To install `youtube-comment-scraper` in your global environment,
```sh
$ npm install -g youtube-comment-scraper
```
after that, you can use `scraper` command.


## Usage
```
Usage: scraper url [options]

        url
                URL for a Youtube video page or video ID.

        --help, -h
                Displays help information about this script

        --version
                Displays version info
```

Output is a JSON format text.
Its schema looks like

```json
{
  "id": "the video ID.",
  "channel":{
    "id": "ID of the channel the video belongs to.",
    "name" : "the channel name."
  },
  "comments": [
    {
      "root": "root (parent) comment body.",
      "author": "author of the root comment.",
      "author_id": "ID of the author",
      "like": "like score (summation of +1 for like and -1 for dislike).",
      "children": [
        {
          "comment": "reply comment.",
          "author": "author of the reply comment.",
          "author_id": "author ID",
          "like": "like score."
        },
        ...
      ]
    },
    ...
  ]
}
```


Method
---------
```js
var scraper = require("youtube-comment-scraper");
```

### `scraper.comments(url)`
Scraping a given Youtube page and return a set of comments.

- Args:
  - url: URL of the target page or video ID.
- Returns:
 Promise object. Use "then" to receive results.

### `scraper.channel(url)`
Scraping a Youtube channel page and return a description of the channel.

- Args:
  - id: channel ID.
- Returns:
  Promise object. Use "then" method to receive results.

### `scraper.close()`
Cleanup this module. After all scrapings have done, this method should be called.
Otherwise, some instances of PhantomJS will keep running and it prevents
finishing main process.

### example
```js
scraper.comments(some_url).then(function(res) {
  // Printing the result.
  console.log(JSON.stringify({
    url: some_url,
    comments: res
  }));

  // Close scraper.
  scraper.close();
});
```

For developers
-----------------

### Build
Run the following two command.

```sh
$ npm install
$ npm run build
```

### Run

```sh
$ ./bin/cli.js <url>
```

`<url>` is a Youtube url.

License
--------
This software is released under the MIT License, see [LICENSE](LICENSE).