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[](https://requests-cache.readthedocs.io)
[](https://github.com/requests-cache/requests-cache/actions)
[](https://codecov.io/gh/requests-cache/requests-cache)
[](https://requests-cache.readthedocs.io/en/stable/)
[](https://www.codeshelter.co/)
[](https://pypi.org/project/requests-cache)
[](https://anaconda.org/conda-forge/requests-cache)
[](https://pypi.org/project/requests-cache)
[](https://pypi.org/project/requests-cache)
## Summary
**requests-cache** is a persistent HTTP cache that provides an easy way to get better
performance with the python [requests](https://requests.readthedocs.io/) library.
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Complete project documentation can be found at [requests-cache.readthedocs.io](https://requests-cache.readthedocs.io).
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## Features
* 🍰 **Ease of use:** Keep using the `requests` library you're already familiar with. Add caching
with a [drop-in replacement](https://requests-cache.readthedocs.io/en/stable/user_guide/general.html#sessions)
for `requests.Session`, or
[install globally](https://requests-cache.readthedocs.io/en/stable/user_guide/general.html#patching)
to add transparent caching to all `requests` functions.
* 🚀 **Performance:** Get sub-millisecond response times for cached responses. When they expire, you
still save time with
[conditional requests](https://requests-cache.readthedocs.io/en/stable/user_guide/headers.html#conditional-requests).
* 💾 **Persistence:** Works with several
[storage backends](https://requests-cache.readthedocs.io/en/stable/user_guide/backends.html)
including SQLite, Redis, MongoDB, and DynamoDB; or save responses as plain JSON files, YAML,
and more
* 🕗 **Expiration:** Use
[Cache-Control](https://requests-cache.readthedocs.io/en/stable/user_guide/headers.html#cache-control)
and other standard HTTP headers, define your own expiration schedule, keep your cache clutter-free
with backends that natively support TTL, or any combination of strategies
* ⚙️ **Customization:** Works out of the box with zero config, but with a robust set of features for
configuring and extending the library to suit your needs
* 🧩 **Compatibility:** Can be combined with other
[popular libraries based on requests](https://requests-cache.readthedocs.io/en/stable/user_guide/compatibility.html)
## Quickstart
First, install with pip:
```bash
pip install requests-cache
```
Then, use [requests_cache.CachedSession](https://requests-cache.readthedocs.io/en/stable/modules/requests_cache.session.html)
to make your requests. It behaves like a normal
[requests.Session](https://requests.readthedocs.io/en/latest/user/advanced/#session-objects),
but with caching behavior.
To illustrate, we'll call an endpoint that adds a delay of 1 second, simulating a slow or
rate-limited website.
**This takes 1 minute:**
```python
import requests
session = requests.Session()
for i in range(60):
session.get('https://httpbin.org/delay/1')
```
**This takes 1 second:**
```python
import requests_cache
session = requests_cache.CachedSession('demo_cache')
for i in range(60):
session.get('https://httpbin.org/delay/1')
```
With caching, the response will be fetched once, saved to `demo_cache.sqlite`, and subsequent
requests will return the cached response near-instantly.
### Patching
If you don't want to manage a session object, or just want to quickly test it out in your
application without modifying any code, requests-cache can also be installed globally, and all
requests will be transparently cached:
```python
import requests
import requests_cache
requests_cache.install_cache('demo_cache')
requests.get('https://httpbin.org/delay/1')
```
### Headers and Expiration
By default, requests-cache will keep cached responses indefinitely. In most cases, you will want to
use one of the two following strategies to balance cache freshness and performance:
**Define exactly how long to keep responses:**
Use the `expire_after` parameter to set a fixed expiration time for all new responses:
```python
from requests_cache import CachedSession
from datetime import timedelta
# Keep responses for 360 seconds
session = CachedSession('demo_cache', expire_after=360)
# Or use timedelta objects to specify other units of time
session = CachedSession('demo_cache', expire_after=timedelta(hours=1))
```
See [Expiration](https://requests-cache.readthedocs.io/en/stable/user_guide/expiration.html) for
more features and settings.
**Use Cache-Control headers:**
Use the `cache_control` parameter to enable automatic expiration based on `Cache-Control` and other
standard HTTP headers sent by the server:
```python
from requests_cache import CachedSession
session = CachedSession('demo_cache', cache_control=True)
```
See [Cache Headers](https://requests-cache.readthedocs.io/en/stable/user_guide/headers.html)
for more details.
### Settings
The default settings work well for most use cases, but there are plenty of ways to customize
caching behavior when needed. Here is a quick example of some of the options available:
```python
from datetime import timedelta
from requests_cache import CachedSession
session = CachedSession(
'demo_cache',
use_cache_dir=True, # Save files in the default user cache dir
cache_control=True, # Use Cache-Control response headers for expiration, if available
expire_after=timedelta(days=1), # Otherwise expire responses after one day
allowable_codes=[200, 400], # Cache 400 responses as a solemn reminder of your failures
allowable_methods=['GET', 'POST'], # Cache whatever HTTP methods you want
ignored_parameters=['api_key'], # Don't match this request param, and redact if from the cache
match_headers=['Accept-Language'], # Cache a different response per language
stale_if_error=True, # In case of request errors, use stale cache data if possible
)
```
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## Next Steps
To find out more about what you can do with requests-cache, see:
* [User Guide](https://requests-cache.readthedocs.io/en/stable/user_guide.html)
* [Examples](https://requests-cache.readthedocs.io/en/stable/examples.html)
* [API Reference](https://requests-cache.readthedocs.io/en/stable/reference.html)
* [Project Info](https://requests-cache.readthedocs.io/en/stable/project_info.html)
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