How do I save scraped data in Scrapy?

Scraped data in Scrapy can be saved in various formats like JSON, XML, and CSV. After extracting the data, the Scrapy framework provides built-in functionality to export the data into a file.

Here is how to do it:

Using Command Line

After creating your Scrapy spider, you can save the scraped data via the command line. For example, if you want to save the data in JSON format, use the following command:

scrapy crawl myspider -o output.json

The -o option tells Scrapy to export the scraped data into a file. The file will be named output.json. If you want to save it in another format, just change the file extension to .xml or .csv.

Using Pipelines

Another way to save scraped data in Scrapy is by using pipelines. Pipelines are a series of processing units that process the data once it has been scraped.

First, define your item pipeline. An item pipeline is a Python class where you define how to process and where to store the scraped data.

import json

class JsonWriterPipeline(object):

    def open_spider(self, spider):
        self.file = open('output.jl', 'w')

    def close_spider(self, spider):
        self.file.close()

    def process_item(self, item, spider):
        line = json.dumps(dict(item)) + "\n"
        self.file.write(line)
        return item

Then, in your settings.py file, add your item pipeline:

ITEM_PIPELINES = {'myspider.pipelines.JsonWriterPipeline': 1}

The ITEM_PIPELINES setting is a dictionary where keys are the pipeline classes and the values are integers that determine the order of processing (lower values have higher priority).

With this setup, Scrapy will use the JsonWriterPipeline to process and store the scraped items.

In Summary

Scrapy provides two main ways to save scraped data: via the command line and using pipelines. The command line method is straightforward and requires little setup, but it doesn't offer much control or flexibility. On the other hand, pipelines require more setup but give you complete control over how the scraped data is processed and stored.