# Exceptions

## Built-in Exceptions reference

Here’s a list of all exceptions included in Scrapy and their usage.

### CloseSpider

exception scrapy.exceptions.CloseSpider(reason='cancelled')

  This exception can be raised from a spider callback to request the spider to be closed/stopped. Supported arguments:

  Parameters:

    reason (str) – the reason for closing

For example:

    def parse_page(self, response):
        if "Bandwidth exceeded" in response.body:
            raise CloseSpider("bandwidth_exceeded")

### DontCloseSpider

exception scrapy.exceptions.DontCloseSpider

This exception can be raised in a `spider_idle` signal handler to prevent the spider from being closed.

### DropItem

exception scrapy.exceptions.DropItem

The exception that must be raised by item pipeline stages to stop processing an Item. For more information see Item Pipeline.

### IgnoreRequest

exception scrapy.exceptions.IgnoreRequest

This exception can be raised by the Scheduler or any downloader middleware to indicate that the request should be ignored.

### NotConfigured

exception scrapy.exceptions.NotConfigured

This exception can be raised by some components to indicate that they will remain disabled. Those components include:

- Extensions

- Item pipelines

- Downloader middlewares

- Spider middlewares

The exception must be raised in the component’s `__init__` method.

### NotSupported

exception scrapy.exceptions.NotSupported

This exception is raised to indicate an unsupported feature.

### StopDownload

exception scrapy.exceptions.StopDownload(fail=True)

Raised from a `bytes_received` or `headers_received` signal handler to indicate that no further bytes should be downloaded for a response.

The `fail` boolean parameter controls which method will handle the resulting response:

- If `fail=True` (default), the request errback is called. The response object is available as the `response` attribute of the `StopDownload` exception, which is in turn stored as the `value` attribute of the received `Failure` object. This means that in an errback defined as `def errback(self, failure)`, the response can be accessed though `failure.value.response`.

- If `fail=False`, the request callback is called instead.

In both cases, the response could have its body truncated: the body contains all bytes received up until the exception is raised, including the bytes received in the signal handler that raises the exception. Also, the response object is marked with `"download_stopped"` in its `flags` attribute.

Note

`fail` is a keyword-only parameter, i.e. raising `StopDownload(False)` or `StopDownload(True)` will raise a `TypeError`.

See the documentation for the `bytes_received` and `headers_received` signals and the Stopping the download of a Response topic for additional information and examples.