mirror of
https://github.com/facebook/Haxl.git
synced 2024-12-25 01:31:31 +03:00
48 lines
2.1 KiB
Markdown
48 lines
2.1 KiB
Markdown
|
|
|
|
# Haxl
|
|
|
|
Haxl is a Haskell library that simplifies access to remote data, such
|
|
as databases or web-based services. Haxl can automatically
|
|
|
|
* batch multiple requests to the same data source,
|
|
* request data from multiple data sources concurrently,
|
|
* cache previous requests.
|
|
|
|
Having all this handled for you behind the scenes means that your
|
|
data-fetching code can be much cleaner and clearer than it would
|
|
otherwise be if it had to worry about optimizing data-fetching. We'll
|
|
give some examples of how this works in the pages linked below.
|
|
|
|
There are two Haskell packages here:
|
|
|
|
* `haxl`: The core Haxl framework
|
|
* `haxl-facebook` (in [example/facebook](example/facebook)): An (incomplete) example data source for accessing the Facebook Graph API
|
|
|
|
To use Haxl in your own application, you will likely need to build one or more
|
|
*data sources*: the thin layer between Haxl and the data that you want
|
|
to fetch, be it a database, a web API, a cloud service, or whatever.
|
|
The `haxl-facebook` package shows how we might build a Haxl data
|
|
source based on the existing `fb` package for talking to the Facebook
|
|
Graph API.
|
|
|
|
## Where to go next?
|
|
|
|
* [The Story of Haxl](https://code.facebook.com/posts/302060973291128/open-sourcing-haxl-a-library-for-haskell/)
|
|
explains how Haxl came about at Facebook, and discusses our
|
|
particular use case.
|
|
|
|
* [An example Facebook data source](example/facebook/readme.md) walks
|
|
through building an example data source that queries the Facebook
|
|
Graph API concurrently.
|
|
|
|
* [The N+1 Selects Problem](example/sql/readme.md) explains how Haxl
|
|
can address a common performance problem with SQL queries by
|
|
automatically batching multiple queries into a single query,
|
|
completely invisibly to the programmer.
|
|
|
|
* [Haxl Documentation](http://hackage.haskell.org/package/haxl) on
|
|
Hackage.
|
|
|
|
* [There is no Fork: An Abstraction for Efficient, Concurrent, and Concise Data Access](http://community.haskell.org/~simonmar/papers/haxl-icfp14.pdf), our paper on Haxl, accepted for publication at ICFP'14.
|