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Made the foreword less defensive.

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Armin Ronacher 2011-08-26 21:42:17 +02:00
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docs/foreword.rst
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@ -9,27 +9,30 @@ What does "micro" mean?
-----------------------
To me, the "micro" in microframework refers not only to the simplicity and
small size of the framework, but also to the typically limited complexity
and size of applications that are written with the framework. Also the
fact that you can have an entire application in a single Python file. To
be approachable and concise, a microframework sacrifices a few features
that may be necessary in larger or more complex applications.
small size of the framework, but also the fact that it does not make much
decisions for you. While Flask does pick a templating engine for you, we
won't make such decisions for your datastore or other parts.
For example, Flask uses thread-local objects internally so that you don't
have to pass objects around from function to function within a request in
order to stay threadsafe. While this is a really easy approach and saves
you a lot of time, it might also cause some troubles for very large
applications because changes on these thread-local objects can happen
anywhere in the same thread.
For us however the term “micro” does not mean that the whole implementation
has to fit into a single Python file.
Flask provides some tools to deal with the downsides of this approach but
it might be an issue for larger applications because in theory
modifications on these objects might happen anywhere in the same thread.
One of the design decisions with Flask was that simple tasks should be
simple and not take up a lot of code and yet not limit yourself. Because
of that we took a few design choices that some people might find
surprising or unorthodox. For example, Flask uses thread-local objects
internally so that you don't have to pass objects around from function to
function within a request in order to stay threadsafe. While this is a
really easy approach and saves you a lot of time, it might also cause some
troubles for very large applications because changes on these thread-local
objects can happen anywhere in the same thread. In order to solve these
problems we don't hide the thread locals for you but instead embrace them
and provide you with a lot of tools to make it as pleasant as possible to
work with them.
Flask is also based on convention over configuration, which means that
many things are preconfigured. For example, by convention, templates and
static files are in subdirectories within the Python source tree of the
application.
application. While this can be changed you usually don't have to.
The main reason however why Flask is called a "microframework" is the idea
to keep the core simple but extensible. There is no database abstraction
@ -40,22 +43,15 @@ was implemented in Flask itself. There are currently extensions for
object relational mappers, form validation, upload handling, various open
authentication technologies and more.
However Flask is not much code and it is built on a very solid foundation
and with that it is very easy to adapt for large applications. If you are
interested in that, check out the :ref:`becomingbig` chapter.
Since Flask is based on a very solid foundation there is not a lot of code
in Flask itself. As such it's easy to adapt even for lage applications
and we are making sure that you can either configure it as much as
possible by subclassing things or by forking the entire codebase. If you
are interested in that, check out the :ref:`becomingbig` chapter.
If you are curious about the Flask design principles, head over to the
section about :ref:`design`.
A Framework and an Example
--------------------------
Flask is not only a microframework; it is also an example. Based on
Flask, there will be a series of blog posts that explain how to create a
framework. Flask itself is just one way to implement a framework on top
of existing libraries. Unlike many other microframeworks, Flask does not
try to implement everything on its own; it reuses existing code.
Web Development is Dangerous
----------------------------