Create different documents from the same sources via Jinja (object method)

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With Jinja, you can define objects (audience, platform, version, etc.) and include or exclude text blocks according to their attributes.

Create the following conditional-text.rst file:

Using conditional text
=================================

{% if public.elec %}

.. admonition:: Danger for electricians

Risk of electrocution

Do not touch electrical wires.

{% else %}

.. admonition:: Danger for plumbers

Risk of drowning

Do not dive into the pool.

{% endif %}

Define an Audience class with two attributes for plumbers and electricians:

class Audience:
    def __init__(self,electrician,plumber):
        self.elec=electrician
        self.plum=plumber

Create an instance of the Audience class whose value is true for electricians and false for plumbers:
```
user=Audience(True,False)
```

Create and run the following script:

#!/usr/bin/python
class Audience:
    def __init__(self,electrician,plumber):
        self.elec=electrician
        self.plum=plumber

import jinja2
import sys
reload(sys)
sys.setdefaultencoding('utf8')

user=Audience(True,False)
env = jinja2.Environment(loader=jinja2.FileSystemLoader('./'))
template = env.get_template('texte-conditionnel.rst')
string=template.render(public=user)

print(string)

The contents of the conditional-text.rst file are overwritten and contain only the information intended for electricians.

Create a condition for audiences other than electricians or plumbers:

Using conditional text
=================================

{% if public.elec %}

.. admonition:: Danger for electricians

Risk of electrocution

Do not touch electrical wires.

{% elif public.plum %}

.. admonition:: Danger for plumbers

Risk of drowning

Do not dive into the pool.

{% else %}

.. admonition:: No danger

If you're not a plumber or an electrician, you're not in any
no danger.

{% endif %}

Create a new class for seasons:

class Season:
    def __init__(self,winter,spring,summer,autumn):
        self.win=winter
        self.spr=spring
        self.sum=summer
        self.aut=autumn

Create more complex conditions:

Using conditional text
=================================

{% if public.elec %}

.. admonition:: Danger for electricians

Risk of electrocution

Do not touch electrical wires.

{% elif public.plum and seas.wint %}

.. admonition:: Danger for plumbers

Risk of fracture

Do not dive into the frozen pool.

{% elif public.plum and seas.summ %}

.. admonition:: Danger for plumbers

Risk of hydrocution

Do not dive into cold water when it is hot.

{% elif public.plum and seas.spri or seas.autu %}

.. admonition:: Danger for plumbers

Risk of something

Don't dive into the pool, you never know.

{% else %}

.. admonition:: No danger

If you're not a plumber or an electrician, you're not in any
no danger.

{% endif %}

Vary the values of the Audience and Season class instances to filter the content of the conditional-text.rst file.

#!/usr/bin/python
class Audience:
    def __init__(self,electrician,plumber):
        self.elec=electrician
        self.plum=plumber

class Season:
    def __init__(self,winter,spring,summer,autumn):
        self.wint=winter
        self.spri=spring
        self.summ=summer
        self.autu=autumn

import jinja2
import sys
reload(sys)
sys.setdefaultencoding('utf8')

user=Audience(False,True)
when=Season(False,False,False,True)
env = jinja2.Environment(loader=jinja2.FileSystemLoader('./'))
template = env.get_template('conditional-text.rst')
string=template.render(public=user,seas=when)

print(string)

Use a more readable variant in the content file:

It may be more intuitive to specify a user-friendly string value in the content file, especially if editors are unfamiliar with object-oriented programming, as the == equality test is more meaningful to most people.

Using conditional text
=================================

{% if public.personae == "electrician" %}

.. admonition:: Danger for electricians

   Risk of electrocution

   Do not touch electrical wires.

{% elif public.personae == "plumber" and public.season == "winter" %}

.. admonition:: Danger for plumbers

   Risk of fracture

   Do not dive into the frozen pool.

{% elif public.personae == "plumber" and public.season == "summer" %}

.. admonition:: Danger for plumbers

   Risk of hydrocution

   Do not dive into cold water when it is hot.

{% elif public.personae == "plumber" and public.season == "spring" or public.season == "autumn" %}

.. admonition:: Danger for plumbers

   Risk of something

   Don't dive into the pool, you never know.

{% else %}

.. admonition:: No danger

   If you're not a plumber or an electrician, you're not in any
   no danger.

{% endif %}

It’s more economical to use a single object class, even if it does mix cabbages and carrots (as much in this far-fetched example as in real life, where you’d mix audiences, versions, platforms, etc.).

#!/usr/bin/python
class Audience:
    def __init__(self,pers,seas):
        self.personae=pers
        self.season=seas

import jinja2
import sys
reload(sys)
sys.setdefaultencoding('utf8')

user=Audience("plumber", "winter")
env = jinja2.Environment(loader=jinja2.FileSystemLoader('./'))
template = env.get_template('conditional-text.rst')
string=template.render(public=user)

print(string)

Modify your script to indicate the public and the season as parameters:

Usage:

./profiling.py plumber autumn

If you’ve been paying close attention, you’ll have noticed that this script renders the else condition in the content file useless, since the parameter values are tested before execution.

To allow the passage of unexpected values and display the contents of the else block, the code must be modified as follows:

#!/usr/bin/python
# coding: utf8
class Audience:
    def __init__(self,pers,seas):
        self.personae=pers
        self.season=seas

import jinja2
import sys
reload(sys)
sys.setdefaultencoding('utf8')

if len(sys.argv) == 3:
    pubparam=str(sys.argv[1])
seasparam=str(sys.argv[2])
user=Audience(pubparam,seasparam)
env = jinja2.Environment(loader=jinja2.FileSystemLoader('./'))
template = env.get_template('texte-conditionnel.rst')
string=template.render(public=user)
print(string)
else:
    print('Please indicate public and season')