Raspado de un sitio web de películas en línea

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Empecemos con otro ejemplo de un sitio web del mundo real. Vamos a elegir para raspar un sitio web de películas.

Añadamos una nueva clase y llamémosla "MovieScraper":

Ahora vamos a echar un vistazo en el sitio que vamos a raspar:

Esto forma parte del HTML de la página de inicio que vemos en el sitio web:

<div id="movie-featured" class="movies-list movies-list-full tab-pane in fade active">
    <div data-movie-id="20746" class="ml-item">
        <a href="https://website.com/film/king-arthur-legend-of-the-sword-20746/">
            <span class="mli-quality">CAM</span>
            <img data-original="https://img.gocdn.online/2017/05/16/poster/2116d6719c710eabe83b377463230fbe-king-arthur-legend-of-the-sword.jpg" 
                 class="lazy thumb mli-thumb" alt="King Arthur: Legend of the Sword"
                  src="https://img.gocdn.online/2017/05/16/poster/2116d6719c710eabe83b377463230fbe-king-arthur-legend-of-the-sword.jpg" 
                 style="display: inline-block;">
            <span class="mli-info"><h2>King Arthur: Legend of the Sword</h2></span>
        </a>
    </div>
    <div data-movie-id="20724" class="ml-item">
        <a href="https://website.com/film/snatched-20724/" >
            <span class="mli-quality">CAM</span>
            <img data-original="https://img.gocdn.online/2017/05/16/poster/5ef66403dc331009bdb5aa37cfe819ba-snatched.jpg" 
                 class="lazy thumb mli-thumb" alt="Snatched" 
                 src="https://img.gocdn.online/2017/05/16/poster/5ef66403dc331009bdb5aa37cfe819ba-snatched.jpg" 
                 style="display: inline-block;">
            <span class="mli-info"><h2>Snatched</h2></span>
        </a>
    </div>
</div>
<div id="movie-featured" class="movies-list movies-list-full tab-pane in fade active">
    <div data-movie-id="20746" class="ml-item">
        <a href="https://website.com/film/king-arthur-legend-of-the-sword-20746/">
            <span class="mli-quality">CAM</span>
            <img data-original="https://img.gocdn.online/2017/05/16/poster/2116d6719c710eabe83b377463230fbe-king-arthur-legend-of-the-sword.jpg" 
                 class="lazy thumb mli-thumb" alt="King Arthur: Legend of the Sword"
                  src="https://img.gocdn.online/2017/05/16/poster/2116d6719c710eabe83b377463230fbe-king-arthur-legend-of-the-sword.jpg" 
                 style="display: inline-block;">
            <span class="mli-info"><h2>King Arthur: Legend of the Sword</h2></span>
        </a>
    </div>
    <div data-movie-id="20724" class="ml-item">
        <a href="https://website.com/film/snatched-20724/" >
            <span class="mli-quality">CAM</span>
            <img data-original="https://img.gocdn.online/2017/05/16/poster/5ef66403dc331009bdb5aa37cfe819ba-snatched.jpg" 
                 class="lazy thumb mli-thumb" alt="Snatched" 
                 src="https://img.gocdn.online/2017/05/16/poster/5ef66403dc331009bdb5aa37cfe819ba-snatched.jpg" 
                 style="display: inline-block;">
            <span class="mli-info"><h2>Snatched</h2></span>
        </a>
    </div>
</div>
HTML

Como podemos ver, tenemos el ID de la película, el Título y el Enlace a la página detallada.

Empecemos a raspar este conjunto de datos:

public class MovieScraper : WebScraper
{
    public override void Init()
    {
        License.LicenseKey = "LicenseKey";
        this.LoggingLevel = WebScraper.LogLevel.All;
        this.WorkingDirectory = AppSetting.GetAppRoot() + @"\MovieSample\Output\";
        this.Request("www.website.com", Parse);
    }
    public override void Parse(Response response)
    {
        foreach (var Divs in response.Css("#movie-featured > div"))
        {
            if (Divs.Attributes ["class"] != "clearfix")
            {
                var MovieId = Divs.GetAttribute("data-movie-id");
                var link = Divs.Css("a")[0];
                var MovieTitle = link.TextContentClean;
                Scrape(new ScrapedData() { { "MovieId", MovieId }, { "MovieTitle", MovieTitle } }, "Movie.Jsonl");
            }
        }           
    }
}
public class MovieScraper : WebScraper
{
    public override void Init()
    {
        License.LicenseKey = "LicenseKey";
        this.LoggingLevel = WebScraper.LogLevel.All;
        this.WorkingDirectory = AppSetting.GetAppRoot() + @"\MovieSample\Output\";
        this.Request("www.website.com", Parse);
    }
    public override void Parse(Response response)
    {
        foreach (var Divs in response.Css("#movie-featured > div"))
        {
            if (Divs.Attributes ["class"] != "clearfix")
            {
                var MovieId = Divs.GetAttribute("data-movie-id");
                var link = Divs.Css("a")[0];
                var MovieTitle = link.TextContentClean;
                Scrape(new ScrapedData() { { "MovieId", MovieId }, { "MovieTitle", MovieTitle } }, "Movie.Jsonl");
            }
        }           
    }
}
Public Class MovieScraper
	Inherits WebScraper

	Public Overrides Sub Init()
		License.LicenseKey = "LicenseKey"
		Me.LoggingLevel = WebScraper.LogLevel.All
		Me.WorkingDirectory = AppSetting.GetAppRoot() & "\MovieSample\Output\"
		Me.Request("www.website.com", AddressOf Parse)
	End Sub
	Public Overrides Sub Parse(ByVal response As Response)
		For Each Divs In response.Css("#movie-featured > div")
			If Divs.Attributes ("class") <> "clearfix" Then
				Dim MovieId = Divs.GetAttribute("data-movie-id")
				Dim link = Divs.Css("a")(0)
				Dim MovieTitle = link.TextContentClean
				Scrape(New ScrapedData() From {
					{ "MovieId", MovieId },
					{ "MovieTitle", MovieTitle }
				},
				"Movie.Jsonl")
			End If
		Next Divs
	End Sub
End Class
VB   C#

¿Qué hay de nuevo en este código?

La propiedad Directorio de trabajo se utiliza para establecer el directorio de trabajo principal para todos los datos raspados y sus archivos relacionados.

Hagamos más.

¿Y si necesitamos construir objetos tipados que contengan datos raspados en objetos formateados?

Vamos a implementar una clase de película que contendrá nuestros datos formateados:

public class Movie
{
    public int Id { get; set; }
    public string Title { get; set; }
    public string URL { get; set; }
}
public class Movie
{
    public int Id { get; set; }
    public string Title { get; set; }
    public string URL { get; set; }
}
IRON VB CONVERTER ERROR developers@ironsoftware.com
VB   C#

Ahora actualizaremos nuestro código:

public class MovieScraper : WebScraper
{
    public override void Init()
    {
        License.LicenseKey = "LicenseKey";
        this.LoggingLevel = WebScraper.LogLevel.All;
        this.WorkingDirectory = AppSetting.GetAppRoot() + @"\MovieSample\Output\";
        this.Request("https://website.com/", Parse);
    }
    public override void Parse(Response response)
    {
        foreach (var Divs in response.Css("#movie-featured > div"))
        {
            if (Divs.Attributes ["class"] != "clearfix")
            {
                var movie = new Movie();
                movie.Id = Convert.ToInt32( Divs.GetAttribute("data-movie-id"));
                var link = Divs.Css("a")[0];
                movie.Title = link.TextContentClean;
                movie.URL = link.Attributes ["href"];
                Scrape(movie, "Movie.Jsonl");
            }
        }
    }
}
public class MovieScraper : WebScraper
{
    public override void Init()
    {
        License.LicenseKey = "LicenseKey";
        this.LoggingLevel = WebScraper.LogLevel.All;
        this.WorkingDirectory = AppSetting.GetAppRoot() + @"\MovieSample\Output\";
        this.Request("https://website.com/", Parse);
    }
    public override void Parse(Response response)
    {
        foreach (var Divs in response.Css("#movie-featured > div"))
        {
            if (Divs.Attributes ["class"] != "clearfix")
            {
                var movie = new Movie();
                movie.Id = Convert.ToInt32( Divs.GetAttribute("data-movie-id"));
                var link = Divs.Css("a")[0];
                movie.Title = link.TextContentClean;
                movie.URL = link.Attributes ["href"];
                Scrape(movie, "Movie.Jsonl");
            }
        }
    }
}
Public Class MovieScraper
	Inherits WebScraper

	Public Overrides Sub Init()
		License.LicenseKey = "LicenseKey"
		Me.LoggingLevel = WebScraper.LogLevel.All
		Me.WorkingDirectory = AppSetting.GetAppRoot() & "\MovieSample\Output\"
		Me.Request("https://website.com/", AddressOf Parse)
	End Sub
	Public Overrides Sub Parse(ByVal response As Response)
		For Each Divs In response.Css("#movie-featured > div")
			If Divs.Attributes ("class") <> "clearfix" Then
				Dim movie As New Movie()
				movie.Id = Convert.ToInt32(Divs.GetAttribute("data-movie-id"))
				Dim link = Divs.Css("a")(0)
				movie.Title = link.TextContentClean
				movie.URL = link.Attributes ("href")
				Scrape(movie, "Movie.Jsonl")
			End If
		Next Divs
	End Sub
End Class
VB   C#

¿Qué hay de nuevo?

  1. Implementamos Movie Class para mantener nuestros datos raspados
  2. Pasamos objetos de película al método Scrape y este entiende nuestro formato y guarda en un formato definido como podemos ver aquí:

    Empecemos a raspar una página más detallada.

La página de películas tiene este aspecto:

<div class="mvi-content">
    <div class="thumb mvic-thumb"
         style="background-image: url(https://img.gocdn.online/2017/04/28/poster/5a08e94ba02118f22dc30f298c603210-guardians-of-the-galaxy-vol-2.jpg);"></div>
    <div class="mvic-desc">
        <h3>Guardians of the Galaxy Vol. 2</h3>        
        <div class="desc">
            Set to the backdrop of Awesome Mixtape #2, Marvel's Guardians of the Galaxy Vol. 2 continues the team's adventures as they travel throughout the cosmos to help Peter Quill learn more about his true parentage.
        </div>
        <div class="mvic-info">
            <div class="mvici-left">
                <p>
                    <strong>Genre: </strong>
                    <a href="https://Domain/genre/action/" title="Action">Action</a>,
                    <a href="https://Domain/genre/adventure/" title="Adventure">Adventure</a>,
                    <a href="https://Domain/genre/sci-fi/" title="Sci-Fi">Sci-Fi</a>
                </p>
                <p>
                    <strong>Actor: </strong>
                    <a target="_blank" href="https://Domain/actor/chris-pratt" title="Chris Pratt">Chris Pratt</a>,
                    <a target="_blank" href="https://Domain/actor/-zoe-saldana" title="Zoe Saldana">Zoe Saldana</a>,
                    <a target="_blank" href="https://Domain/actor/-dave-bautista-" title="Dave Bautista">Dave Bautista</a>
                </p>
                <p>
                    <strong>Director: </strong>
                    <a href="#" title="James Gunn">James Gunn</a>
                </p>
                <p>
                    <strong>Country: </strong>
                    <a href="https://Domain/country/us" title="United States">United States</a>
                </p>
            </div>
            <div class="mvici-right">
                <p><strong>Duration:</strong> 136 min</p>
                <p><strong>Quality:</strong> <span class="quality">CAM</span></p>
                <p><strong>Release:</strong> 2017</p>
                <p><strong>IMDb:</strong> 8.3</p>
            </div>
            <div class="clearfix"></div>
        </div>
        <div class="clearfix"></div>
    </div>
    <div class="clearfix"></div>
</div>
<div class="mvi-content">
    <div class="thumb mvic-thumb"
         style="background-image: url(https://img.gocdn.online/2017/04/28/poster/5a08e94ba02118f22dc30f298c603210-guardians-of-the-galaxy-vol-2.jpg);"></div>
    <div class="mvic-desc">
        <h3>Guardians of the Galaxy Vol. 2</h3>        
        <div class="desc">
            Set to the backdrop of Awesome Mixtape #2, Marvel's Guardians of the Galaxy Vol. 2 continues the team's adventures as they travel throughout the cosmos to help Peter Quill learn more about his true parentage.
        </div>
        <div class="mvic-info">
            <div class="mvici-left">
                <p>
                    <strong>Genre: </strong>
                    <a href="https://Domain/genre/action/" title="Action">Action</a>,
                    <a href="https://Domain/genre/adventure/" title="Adventure">Adventure</a>,
                    <a href="https://Domain/genre/sci-fi/" title="Sci-Fi">Sci-Fi</a>
                </p>
                <p>
                    <strong>Actor: </strong>
                    <a target="_blank" href="https://Domain/actor/chris-pratt" title="Chris Pratt">Chris Pratt</a>,
                    <a target="_blank" href="https://Domain/actor/-zoe-saldana" title="Zoe Saldana">Zoe Saldana</a>,
                    <a target="_blank" href="https://Domain/actor/-dave-bautista-" title="Dave Bautista">Dave Bautista</a>
                </p>
                <p>
                    <strong>Director: </strong>
                    <a href="#" title="James Gunn">James Gunn</a>
                </p>
                <p>
                    <strong>Country: </strong>
                    <a href="https://Domain/country/us" title="United States">United States</a>
                </p>
            </div>
            <div class="mvici-right">
                <p><strong>Duration:</strong> 136 min</p>
                <p><strong>Quality:</strong> <span class="quality">CAM</span></p>
                <p><strong>Release:</strong> 2017</p>
                <p><strong>IMDb:</strong> 8.3</p>
            </div>
            <div class="clearfix"></div>
        </div>
        <div class="clearfix"></div>
    </div>
    <div class="clearfix"></div>
</div>
HTML

Podemos ampliar nuestra clase movie con nuevas propiedades (Descripción, Género, Actor, Director, País, Duración, Puntuación IMDB) pero usaremos (Descripción, Género, Actor) sólo para nuestra muestra.

public class Movie
{
    public int Id { get; set; }
    public string Title { get; set; }
    public string URL { get; set; }
    public string Description { get; set; }
    public List<string> Genre { get; set; }
    public List<string> Actor { get; set; }
}
public class Movie
{
    public int Id { get; set; }
    public string Title { get; set; }
    public string URL { get; set; }
    public string Description { get; set; }
    public List<string> Genre { get; set; }
    public List<string> Actor { get; set; }
}
IRON VB CONVERTER ERROR developers@ironsoftware.com
VB   C#

Ahora navegaremos a la página Detallada para rasparla.

IronWebScraper le permite añadir más a la función de raspado para raspar diferentes tipos de formatos de página

Como podemos ver aquí:

public class MovieScraper : WebScraper
{
    public override void Init()
    {
        License.LicenseKey = "LicenseKey";
        this.LoggingLevel = WebScraper.LogLevel.All;
        this.WorkingDirectory = AppSetting.GetAppRoot() + @"\MovieSample\Output\";
        this.Request("https://domain/", Parse);
    }
    public override void Parse(Response response)
    {
        foreach (var Divs in response.Css("#movie-featured > div"))
        {
            if (Divs.Attributes ["class"] != "clearfix")
            {
                var movie = new Movie();
                movie.Id = Convert.ToInt32( Divs.GetAttribute("data-movie-id"));
                var link = Divs.Css("a")[0];
                movie.Title = link.TextContentClean;
                movie.URL = link.Attributes ["href"];
                this.Request(movie.URL, ParseDetails, new MetaData() { { "movie", movie } });// to scrap Detailed Page
            }
        }           
    }
    public void ParseDetails(Response response)
    {
        var movie = response.MetaData.Get<Movie>("movie");
        var Div = response.Css("div.mvic-desc")[0];
        movie.Description = Div.Css("div.desc")[0].TextContentClean;
        foreach(var Genre in Div.Css("div > p > a"))
        {
            movie.Genre.Add(Genre.TextContentClean);
        }
        foreach (var Actor in Div.Css("div > p:nth-child(2) > a"))
        {
            movie.Actor.Add(Actor.TextContentClean);
        }
        Scrape(movie, "Movie.Jsonl");
    }
}
public class MovieScraper : WebScraper
{
    public override void Init()
    {
        License.LicenseKey = "LicenseKey";
        this.LoggingLevel = WebScraper.LogLevel.All;
        this.WorkingDirectory = AppSetting.GetAppRoot() + @"\MovieSample\Output\";
        this.Request("https://domain/", Parse);
    }
    public override void Parse(Response response)
    {
        foreach (var Divs in response.Css("#movie-featured > div"))
        {
            if (Divs.Attributes ["class"] != "clearfix")
            {
                var movie = new Movie();
                movie.Id = Convert.ToInt32( Divs.GetAttribute("data-movie-id"));
                var link = Divs.Css("a")[0];
                movie.Title = link.TextContentClean;
                movie.URL = link.Attributes ["href"];
                this.Request(movie.URL, ParseDetails, new MetaData() { { "movie", movie } });// to scrap Detailed Page
            }
        }           
    }
    public void ParseDetails(Response response)
    {
        var movie = response.MetaData.Get<Movie>("movie");
        var Div = response.Css("div.mvic-desc")[0];
        movie.Description = Div.Css("div.desc")[0].TextContentClean;
        foreach(var Genre in Div.Css("div > p > a"))
        {
            movie.Genre.Add(Genre.TextContentClean);
        }
        foreach (var Actor in Div.Css("div > p:nth-child(2) > a"))
        {
            movie.Actor.Add(Actor.TextContentClean);
        }
        Scrape(movie, "Movie.Jsonl");
    }
}
Public Class MovieScraper
	Inherits WebScraper

	Public Overrides Sub Init()
		License.LicenseKey = "LicenseKey"
		Me.LoggingLevel = WebScraper.LogLevel.All
		Me.WorkingDirectory = AppSetting.GetAppRoot() & "\MovieSample\Output\"
		Me.Request("https://domain/", AddressOf Parse)
	End Sub
	Public Overrides Sub Parse(ByVal response As Response)
		For Each Divs In response.Css("#movie-featured > div")
			If Divs.Attributes ("class") <> "clearfix" Then
				Dim movie As New Movie()
				movie.Id = Convert.ToInt32(Divs.GetAttribute("data-movie-id"))
				Dim link = Divs.Css("a")(0)
				movie.Title = link.TextContentClean
				movie.URL = link.Attributes ("href")
				Me.Request(movie.URL, AddressOf ParseDetails, New MetaData() From {
					{ "movie", movie }
				}) ' to scrap Detailed Page
			End If
		Next Divs
	End Sub
	Public Sub ParseDetails(ByVal response As Response)
		Dim movie = response.MetaData.Get(Of Movie)("movie")
		Dim Div = response.Css("div.mvic-desc")(0)
		movie.Description = Div.Css("div.desc")(0).TextContentClean
		For Each Genre In Div.Css("div > p > a")
			movie.Genre.Add(Genre.TextContentClean)
		Next Genre
		For Each Actor In Div.Css("div > p:nth-child(2) > a")
			movie.Actor.Add(Actor.TextContentClean)
		Next Actor
		Scrape(movie, "Movie.Jsonl")
	End Sub
End Class
VB   C#

¿Qué hay de nuevo?

  1. Podemos añadir funciones de raspado (ParseDetails) para raspar páginas detalladas
  2. Trasladamos la función Scrape que genera nuestro fichero a la nueva función
  3. Utilizamos la función IronWebScraper (MetaDatos) para pasar nuestro objeto de película a la nueva función scrape
  4. Raspamos la página y guardamos los datos de nuestros objetos de película en un archivo