minor #8742 Add instructions to install dependencies before using them (javiereguiluz)

This PR was merged into the 4.0 branch.

Discussion
----------

Add instructions to install dependencies before using them

The missing ones are being taken care of in other PRs (doctrine, translation, etc.)

Commits
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94fd2e9 Add instructions to install dependencies before using them

Author: weaverryan

email.rst

@@ -12,8 +12,8 @@ own mail servers as well as using popular email providers like `Mandrill`_,
 Installation
 ------------
 
-In applications using :doc:`Symfony Flex </setup/flex>`, execute this command to
-install and enable the mailer:
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the Swift Mailer based mailer before using it:
 
 .. code-block:: terminal
 

forms.rst

@@ -9,6 +9,16 @@ a web developer. Symfony integrates a Form component that makes dealing with
 forms easy. In this article, you'll build a complex form from the ground up,
 learning the most important features of the form library along the way.
 
+Installation
+------------
+
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the form feature before using it:
+
+.. code-block:: terminal
+
+    $ composer require form
+
 .. note::
 
    The Symfony Form component is a standalone library that can be used outside

logging.rst

@@ -1,8 +1,18 @@
 Logging with Monolog
 ====================
 
-Symfony comes with an outside library - called Monolog_ - that allows you to create
-logs that can be stored in a variety of different places.
+Symfony integrates seamlessly with `Monolog`_, the most popular PHP logging
+library, to create and store log messages in a variety of different places.
+
+Installation
+------------
+
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the Monolog based logger before using it:
+
+.. code-block:: terminal
+
+    $ composer require logger
 
 Logging a Message
 -----------------
@@ -19,7 +29,7 @@ your controller::
 
         $logger->info('I just got the logger');
         $logger->error('An error occurred');
-        
+
         $logger->critical('I left the oven on!', array(
             // include extra "context" info in your logs
             'cause' => 'in_hurry',

profiler.rst

@@ -1,6 +1,19 @@
 Profiler
 ========
 
+Symfony provides a powerful profiler to get detailed information about the
+execution of any request.
+
+Installation
+------------
+
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the profiler before using it:
+
+.. code-block:: terminal
+
+    $ composer require profiler
+
 .. toctree::
     :maxdepth: 1
 

security.rst

@@ -14,6 +14,8 @@ is both flexible and (hopefully) fun to work with.
 Since there's a lot to talk about, this article is organized into a few big
 sections:
 
+#. Installing security support;
+
 #. Initial ``security.yml`` setup (*authentication*);
 
 #. Denying access to your app (*authorization*);
@@ -24,6 +26,16 @@ These are followed by a number of small (but still captivating) sections,
 like :ref:`logging out <security-logging-out>` and
 :doc:`encoding user passwords </security/password_encoding>`.
 
+Installation
+------------
+
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the security feature before using it:
+
+.. code-block:: terminal
+
+    $ composer require security
+
 .. _security-firewalls:
 .. _firewalls-authentication:
 

serializer.rst

@@ -11,10 +11,11 @@ its philosophy and the normalizers and encoders terminology.
 
 .. _activating_the_serializer:
 
-Installing the Serializer
--------------------------
+Installation
+------------
 
-Before using the serializer, run this command to install it in your application:
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the serializer before using it:
 
 .. code-block:: terminal
 

validation.rst

@@ -8,9 +8,18 @@ Validation is a very common task in web applications. Data entered in forms
 needs to be validated. Data also needs to be validated before it is written
 into a database or passed to a web service.
 
-Symfony ships with a `Validator`_ component that makes this task easy and
-transparent. This component is based on the
-`JSR303 Bean Validation specification`_.
+Symfony provides a `Validator`_ component that makes this task easy and
+transparent. This component is based on the `JSR303 Bean Validation specification`_.
+
+Installation
+------------
+
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the validator before using it:
+
+.. code-block:: terminal
+
+    $ composer require validator
 
 .. index::
    single: Validation; The basics

workflow/usage.rst

@@ -4,13 +4,19 @@
 How to Create and Use Workflows
 ===============================
 
-Before creating your first workflow, execute this command to install the
-:doc:`Workflow component </components/workflow>` in your application:
+Installation
+------------
+
+In applications using :doc:`Symfony Flex </setup/flex>`, run this command to
+install the workflow feature before using it:
 
 .. code-block:: terminal
 
     $ composer require workflow
 
+Creating a Workflow
+-------------------
+
 A workflow is a process or a lifecycle that your objects go through. Each
 step or stage in the process is called a *place*. You do also define *transitions*
 to that describes the action to get from one place to another.
@@ -163,9 +169,12 @@ like this:
     value ``marking``) attributes of the ``marking_store`` option are optional.
     If omitted, their default values will be used.
 
-With this workflow named ``blog_publishing``, you can now decide what actions
-are allowed on a blog post. For example, inside a controller of an application
-using the :ref:`default services.yaml configuration <service-container-services-load-example>`,
+Using a Workflow
+----------------
+
+Once the ``blog_publishing`` workflow has been created, you can now use it to
+decide what actions are allowed on a blog post. For example, inside a controller
+of an application using the :ref:`default services.yaml configuration <service-container-services-load-example>`,
 you can get the workflow by injecting the Workflow registry service::
 
     // ...