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Grammatical fixes in Foreword and Tutorial

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Kevin Yap 2014-12-12 22:52:36 -08:00
parent 475d7076f0
commit 23fc2e56a8
12 changed files with 98 additions and 96 deletions
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docs/tutorial/dbcon.rst
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@ -4,29 +4,29 @@ Step 3: Database Connections
----------------------------
We have created a function for establishing a database connection with
`connect_db` but by itself that's not particularly useful. Creating and
`connect_db`, but by itself, that's not particularly useful. Creating and
closing database connections all the time is very inefficient, so we want
to keep it around for longer. Because database connections encapsulate a
transaction we also need to make sure that only one request at the time
uses the connection. So how can we elegantly do that with Flask?
transaction, we also need to make sure that only one request at the time
uses the connection. How can we elegantly do that with Flask?
This is where the application context comes into play. So let's start
This is where the application context comes into play, so let's start
there.
Flask provides us with two contexts: the application context and the
request context. For the time being all you have to know is that there
are special variables that use these. For instance the
request context. For the time being, all you have to know is that there
are special variables that use these. For instance, the
:data:`~flask.request` variable is the request object associated with
the current request, whereas :data:`~flask.g` is a general purpose
variable associated with the current application context. We will go into
the details of this a bit later.
For the time being all you have to know is that you can store information
For the time being, all you have to know is that you can store information
safely on the :data:`~flask.g` object.
So when do you put it on there? To do that you can make a helper
function. The first time the function is called it will create a database
connection for the current context and successive calls will return the
function. The first time the function is called, it will create a database
connection for the current context, and successive calls will return the
already established connection::
def get_db():
@ -39,7 +39,7 @@ already established connection::
So now we know how to connect, but how do we properly disconnect? For
that flask provides us with the :meth:`~flask.Flask.teardown_appcontext`
that, Flask provides us with the :meth:`~flask.Flask.teardown_appcontext`
decorator. It's executed every time the application context tears down::
@app.teardown_appcontext
@ -49,11 +49,11 @@ decorator. It's executed every time the application context tears down::
g.sqlite_db.close()
Functions marked with :meth:`~flask.Flask.teardown_appcontext` are called
every time the app context tears down. So what does this mean?
Essentially the app context is created before the request comes in and is
every time the app context tears down. What does this mean?
Essentially, the app context is created before the request comes in and is
destroyed (torn down) whenever the request finishes. A teardown can
happen because of two reasons: either everything went well (the error
parameter will be ``None``) or an exception happened in which case the error
parameter will be ``None``) or an exception happened, in which case the error
is passed to the teardown function.
Curious about what these contexts mean? Have a look at the