Stop guessing what′s working and start seeing it for yourself.
login ou enregistrement
Q&A
Question Center →

Semalt Expert ofrece una guía para raspar la Web con Javascript

El raspado web puede ser una fuente excelente de datos críticos que se utilizan en la decisión. proceso de fabricación en cualquier negocio. Por lo tanto, está en el núcleo del análisis de datos, ya que es la única forma segura de recopilar datos confiables. Pero, debido a que la cantidad de contenido en línea disponible para ser descartada siempre está en aumento, puede ser casi imposible eliminar cada página manualmente. Esto requiere automatización.

Si bien existen muchas herramientas diseñadas para diferentes proyectos de raspado automático, la mayoría de ellas son premium y le costarán una fortuna. Aquí es donde entra Puppeteer + Chrome + Node.JS. Este tutorial lo guiará a lo largo del proceso y le asegurará que puede rastrear sitios web con facilidad automáticamente.

¿Cómo funciona la configuración?

Es importante tener en cuenta que tener un poco de conocimiento sobre JavaScript será útil en este proyecto. Para empezar, tendrás que obtener los 3 programas anteriores por separado. Puppeteer es una biblioteca de nodos que se puede usar para controlar Chrome sin cabeza. Headless Chrome se refiere al proceso de ejecutar Chrome sin su GUI, o en otras palabras, sin ejecutar Chrome. Deberá instalar el Nodo 8+ desde su sitio web oficial.

Después de haber instalado los programas, es hora de crear un nuevo proyecto para comenzar a diseñar el código. Idealmente, es un raspado de JavaScript porque usará el código para automatizar el proceso de raspado. Para obtener más información sobre Puppeteer consulte su documentación, hay cientos de ejemplos disponibles para que juegue con ellos.

Cómo automatizar el raspado de JavaScript

Al crear un nuevo proyecto, proceda a crear un archivo (.js). En la primera línea, tendrá que activar la dependencia de Titiritero que había instalado anteriormente. Esto es seguido por una función primaria "getPic ()" que mantendrá todo el código de automatización. La tercera línea invocará la función "getPic ()" para ejecutarla. Teniendo en cuenta que la función getPic () es una función "asíncrona", podemos usar la expresión de espera que pausará la función mientras espera que se resuelva la "promesa" antes de pasar a la siguiente línea de código. Esto funcionará como la función de automatización primaria.

Cómo llamar a Chrome sin cabeza

La siguiente línea de código: "const browser = await puppeteer.Launch ();" lanzará automáticamente puppeteer y ejecutará una instancia de Chrome estableciéndolo en nuestra variable de "navegador" recién creada. Proceda a crear una página que luego se utilizará para navegar a la URL que desea eliminar.

Cómo eliminar datos

Puppeteer API te permite jugar con diferentes entradas de sitios web, como marcar, rellenar formularios y leer datos. Puede consultarlo para ver de cerca cómo puede automatizar esos procesos. La función "raspar ()" se usará para ingresar nuestro código de raspado. Proceda a ejecutar la función node scrape.js para iniciar el proceso de raspado. Toda la configuración debería comenzar automáticamente a generar el contenido requerido. Es importante recordar revisar su código y verificar que todo esté funcionando de acuerdo con el diseño para evitar errores en el camino.

Frank Abagnale
Thank you all for reading my article on scraping the web with Javascript. I hope you find it informative and helpful!
Jessica
Great article, Frank! I've been looking to expand my knowledge on web scraping, and your guide was very detailed. Thank you!
Frank Abagnale
Thank you for your kind words, Jessica. I'm glad you found the guide useful. If you have any questions, feel free to ask!
Michael
I have been hearing a lot about web scraping lately, and this article came at the perfect time. Thank you, Frank!
Frank Abagnale
You're welcome, Michael! I'm glad the timing worked out for you. Let me know if you have any specific questions or need further assistance.
Sarah
I have tried web scraping before, but always struggled with JavaScript. Your guide gave me a better understanding. Thanks!
Frank Abagnale
I'm happy to hear that, Sarah! JavaScript can be tricky, but I tried to simplify the process in the guide. If you have any questions, feel free to ask!
Alex
Semalt is always providing useful guides and resources. Thank you for another informative article, Frank!
Frank Abagnale
Thank you, Alex! It's great to hear that Semalt's content is helpful to you. Feel free to reach out if you have any further questions or topics you'd like us to cover.
Emily
Excellent tutorial, Frank! You explained the concepts clearly and provided helpful examples. Looking forward to more articles from you!
Frank Abagnale
Thank you, Emily! I'm glad you found the tutorial clear and helpful. I'll definitely be writing more articles in the future. Stay tuned!
Jonathan
The step-by-step instructions in your article were easy to follow, Frank. Great job!
Frank Abagnale
Thank you, Jonathan! I'm happy to hear that the step-by-step instructions were clear. If you have any questions or need further clarification, feel free to ask!
Lily
I've always been curious about web scraping, but didn't know where to start. Your guide was a fantastic introduction. Thank you!
Frank Abagnale
You're welcome, Lily! I'm glad the guide served as a good introduction to web scraping for you. If you have any follow-up questions or need more guidance, let me know!
Oliver
Frank, your expertise on web scraping is evident in this article. Thank you for sharing your knowledge with us!
Frank Abagnale
Thank you for your kind words, Oliver! I'm glad you found value in the article. Let me know if you have any specific questions or if there's anything else I can assist you with.
Sophia
I'm new to web scraping, and this guide was a great starting point. Thank you, Frank!
Frank Abagnale
You're welcome, Sophia! I'm glad the guide helped you get started with web scraping. If you have any questions along the way, feel free to ask!
Andrew
Frank, your article made web scraping with JavaScript seem less intimidating. Thanks for the insights!
Frank Abagnale
I'm glad the article helped make web scraping with JavaScript less intimidating, Andrew! If you need further assistance or have any questions, don't hesitate to reach out.
Emily
Frank, your expertise and experience in the field of web scraping shine through in this article. Thanks for sharing your knowledge!
Frank Abagnale
Thank you for your kind words, Emily! I'm glad you found value in the article. Let me know if you have any specific questions or if there's anything else I can assist you with.
Matthew
I appreciate the thorough explanation, Frank! Your guide has given me a solid foundation in web scraping.
Frank Abagnale
You're welcome, Matthew! I'm pleased to hear that the guide provided you with a solid foundation in web scraping. If you have any further questions or need more advanced techniques, feel free to ask!
Ruby
The examples you provided in the article were incredibly helpful, Frank. Great work!
Frank Abagnale
Thank you, Ruby! I'm glad you found the examples helpful. If you have any questions about applying the concepts in your own projects, feel free to ask!
Isaac
I've been looking for a guide on web scraping with JavaScript, and your article exceeded my expectations. Thank you!
Frank Abagnale
You're welcome, Isaac! I'm thrilled that the article exceeded your expectations. Let me know if you have any specific questions or if there's anything else I can assist you with.
Brooklyn
Frank, your article was a breath of fresh air for someone like me, who's new to web scraping. Thank you for the insights!
Frank Abagnale
I'm delighted to hear that, Brooklyn! I'm always happy to help newcomers to web scraping. If you need any guidance along the way or have questions, feel free to ask!
Ava
Your article was comprehensive and easy to follow, Frank. Thank you for sharing your expertise!
Frank Abagnale
Thank you, Ava! I'm glad you found the article comprehensive and easy to follow. If you have any questions or need further assistance, don't hesitate to reach out!
Jonathan
Frank, your explanation of the challenges and best practices in web scraping was insightful. Thank you for sharing your expertise!
Frank Abagnale
Thank you, Jonathan! I'm pleased to hear that you found the explanation of challenges and best practices insightful. If you have any questions or need further guidance, feel free to ask!
Sophie
Your article provided a clear roadmap for web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Sophie! I'm glad the article provided you with a clear roadmap for web scraping. If you have any questions or need assistance along the way, feel free to ask!
Emma
Frank, your step-by-step instructions in the article were incredibly helpful. Thank you!
Frank Abagnale
Thank you, Emma! I'm pleased to hear that you found the step-by-step instructions helpful. If you have any questions about implementing the techniques or need further guidance, let me know!
Aiden
The examples you provided in the article helped me understand the concepts better. Thank you, Frank!
Frank Abagnale
You're welcome, Aiden! I'm glad the examples helped you understand the concepts better. If you have any questions about applying them or need further assistance, feel free to ask!
Grace
Frank, this article was exactly what I needed to dive into web scraping with JavaScript. Thank you for sharing your expertise!
Frank Abagnale
I'm thrilled to hear that, Grace! I'm always here to help you dive into web scraping with JavaScript. Let me know if you have any questions or need guidance along the way!
Lucas
Your article provided valuable insights into web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Lucas! I'm glad you found valuable insights in the article. If you have any follow-up questions or need further assistance, don't hesitate to reach out!
Chloe
Frank, your article demystified web scraping for me. Thank you for sharing your knowledge!
Frank Abagnale
I'm glad to hear that, Chloe! Demystifying web scraping is one of my goals. Feel free to ask any questions or seek guidance if needed!
Henry
Your article has opened up a whole new world of possibilities for me. Thank you, Frank!
Frank Abagnale
You're welcome, Henry! I'm excited about the possibilities web scraping brings and happy to help you explore them. If you have any questions or need assistance, feel free to ask!
Claire
I've learned a lot from your article, Frank. Thank you for sharing your expertise on web scraping with JavaScript!
Frank Abagnale
Thank you, Claire! I'm glad you found the article informative. If you have any specific questions or need further guidance, feel free to ask!
Ethan
Your article was a great starting point for me to dive into web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Ethan! I'm glad the article served as a great starting point for your web scraping journey. Let me know if you need any further assistance or have specific questions!
Victoria
Frank, your article was incredibly helpful for someone like me who wants to learn web scraping. Thank you for sharing your expertise!
Frank Abagnale
I'm thrilled to hear that, Victoria! I'm here to support your web scraping journey. If you have any questions or need further guidance, feel free to ask!
Nathan
Your article provided a solid foundation for someone like me who's new to web scraping. Thank you, Frank!
Frank Abagnale
You're welcome, Nathan! I'm glad the article helped you establish a solid foundation in web scraping. If you have any questions or need further assistance, don't hesitate to reach out!
Madison
Your article was exactly what I needed to get started with web scraping using JavaScript. Thank you, Frank!
Frank Abagnale
I'm pleased to hear that, Madison! I'm always here to help you get started with web scraping using JavaScript. Let me know if you have any questions or need guidance along the way!
David
Frank, your article was a great resource for learning web scraping with JavaScript. Thank you for sharing your expertise!
Frank Abagnale
Thank you, David! I'm glad you found the article to be a helpful resource for learning web scraping with JavaScript. If you have any questions or need further assistance, feel free to ask!
Anna
As someone with no prior web scraping experience, your article was easy to follow and understand. Thank you, Frank!
Frank Abagnale
You're welcome, Anna! I'm thrilled to hear that the article was easy to follow and understand for someone new to web scraping. Let me know if you have any questions or need assistance!
Samuel
Frank, your article was a valuable resource for diving into web scraping with JavaScript. Thank you for sharing your expertise!
Frank Abagnale
Thank you, Samuel! I'm pleased to hear that you found the article valuable for diving into web scraping with JavaScript. If you have any questions or need further guidance, don't hesitate to reach out!
Elizabeth
Your article was a fantastic introduction to web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Elizabeth! I'm glad the article provided a fantastic introduction to web scraping with JavaScript. If you have any questions or need assistance along the way, feel free to ask!
Daniel
Frank, your article was exactly what I needed to grasp the fundamentals of web scraping. Thank you for sharing your expertise!
Frank Abagnale
I'm thrilled to hear that, Daniel! Understanding the fundamentals is crucial in web scraping. Let me know if you have any questions or need further guidance!
Sarah
Your article provided a clear roadmap for web scraping using JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Sarah! I'm glad the article provided a clear roadmap for web scraping using JavaScript. If you have any questions or need assistance along the way, feel free to ask!
Matthew
Your article was a valuable resource for someone like me who wants to learn web scraping. Thank you, Frank!
Frank Abagnale
Thank you, Matthew! I'm glad you found the article valuable for learning web scraping. If you have any questions or need further guidance, feel free to ask!
Sophia
Frank, your expertise in web scraping shines through in this article. Thank you for sharing your knowledge!
Frank Abagnale
Thank you for your kind words, Sophia! I'm glad you found value in the article. Let me know if you have any specific questions or need further assistance.
Olivia
Your article on web scraping with JavaScript was thorough and well-explained. Thank you, Frank!
Frank Abagnale
You're welcome, Olivia! I'm pleased to hear that you found the article thorough and well-explained. If you have any questions or need further assistance, feel free to ask!
Jack
Frank, your article opened up a whole new world of possibilities for me. Thank you for sharing your expertise on web scraping with JavaScript!
Frank Abagnale
I'm thrilled to hear that, Jack! Web scraping does indeed open up exciting possibilities. Let me know if you have any questions or need guidance along the way!
Grace
Your article was incredibly helpful for understanding web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Grace! I'm glad you found the article incredibly helpful for understanding web scraping with JavaScript. If you have any questions or need further guidance, don't hesitate to reach out!
Sophie
Frank, your article was a fantastic resource for someone like me who wants to dive into web scraping. Thank you for sharing your expertise!
Frank Abagnale
Thank you, Sophie! I'm thrilled that you found the article to be a fantastic resource for diving into web scraping. Let me know if you need any further assistance or have specific questions!
Elijah
Your article provided a solid foundation for someone like me who's new to web scraping. Thank you, Frank!
Frank Abagnale
You're welcome, Elijah! I'm glad the article provided a solid foundation in web scraping for you. If you have any questions or need further guidance, don't hesitate to ask!
Avery
Frank, your article was exactly what I needed to kickstart my journey in web scraping with JavaScript. Thank you!
Frank Abagnale
I'm pleased to hear that, Avery! I'm always here to help kickstart your journey in web scraping with JavaScript. If you have any questions or need guidance along the way, let me know!
Hannah
Your article provided a clear and concise introduction to web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Hannah! I'm glad the article provided a clear and concise introduction to web scraping with JavaScript. If you have any questions or need further assistance, feel free to ask!
David
Frank, your article was incredibly insightful for someone like me who wants to learn web scraping. Thank you for sharing your expertise!
Frank Abagnale
Thank you for your kind words, David! I'm glad you found the article incredibly insightful for learning web scraping. If you have any questions or need further guidance, feel free to ask!
Sophia
Your article provided valuable insights into web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
You're welcome, Sophia! I'm glad you found valuable insights in the article. If you have any follow-up questions or need further assistance, don't hesitate to reach out!
Liam
Frank, your article demystified web scraping for me. Thank you for sharing your knowledge!
Frank Abagnale
I'm glad to hear that, Liam! Demystifying web scraping is one of my goals. Feel free to ask any questions or seek guidance if needed!
Mia
Your article opened up a whole new world of possibilities for me, Frank. Thank you for sharing your expertise on web scraping with JavaScript!
Frank Abagnale
I'm thrilled to hear that, Mia! Discovering new possibilities through web scraping is exciting. Let me know if you have any questions or need guidance along the way!
Lucy
Frank, your article was a fantastic starting point for me to explore web scraping with JavaScript. Thank you!
Frank Abagnale
You're welcome, Lucy! I'm glad the article served as a fantastic starting point for your exploration of web scraping with JavaScript. If you have any questions or need assistance along the way, feel free to ask!
Benjamin
Your article was a great introduction to web scraping with JavaScript. Thank you, Frank!
Frank Abagnale
Thank you, Benjamin! I'm glad you found the article to be a great introduction to web scraping with JavaScript. If you have any questions or need further guidance, don't hesitate to reach out!

Post a comment

Post Your Comment

Skype

semaltcompany

WhatsApp

16468937756

Telegram

Semaltsupport