Upgrading Django (to 1.7)

Slides for my talk at DjangoCon 2014.

Transcript

1. ANDREW PINKHAM
   TOPIC
   DATE AUTHOR
   SEPTEMBER 2014
   UPGRADING DJANGO (TO 1.7)
   DJANGOCON 2014
   ORIGINAL ART BY ERIK DEPRINCE
   WALLPAPER CREATED BY BRYAN VELOSO AND CHRISTIAN METTS

   WALLPAPER SITE HOSTED BY JEFF TRIPLETT
   

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2. $ whoami
   Software Engineer
   
   Freelance Consultant
   
   Technical Instructor
   Andrew Pinkham
   Hi, I’m
   

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3. AUTHOR OF DJANGO UNLEASHED
   SET TO PUBLISH BEGINNING OF 2015
   

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4. $ less updj17
   Django Releases
   
   Versioning and Support
   
   Summary of Previous Releases
   
   Django 1.7 (v1.6 vs v1.7)
   
   Migrations
   
   App Loading
   
   Static Systems Check
   

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7. afrg.co/updj17
   

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8. DJANGO VERSIONS
   UNDERSTANDING DJANGO’S RELEASE PROCESS
   

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9. M.m.μ
   

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10. 1.7.0
    

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11. Pre-Releases
    Alpha
    
    Beta
    
    Release Candidate
    

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12. M.m.μ_#
    

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13. 1.7.0a1
    

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14. 1.7b1
    

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15. 1.7c2
    

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16. Version Support
    Two Versions Supported
    
    Deprecations over Two Versions
    

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17. 1.3 㱺 1.5
    1.4 㱺 1.6
    1.5 㱺 1.7
    Deprecations
    

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18. Support Prior to v1.7
    ! 1.6.6
    
    1.6.5
    
    1.6.4
    
    1.6.3
    
    …
    
    1.6

    1.5.9
    
    1.5.8
    
    1.5.7
    
    1.5.6
    
    …
    
    1.5
    

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19. With Arrival of v1.7
    1.7
 1.6.7
    1.6.6
    
    1.6.5
    
    1.6.4
    
    …
    
    1.6

    1.5.10
    1.5.9
    
    1.5.8
    
    1.5.7
    
    …
    
    1.5
    

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20. Long Term Support (LTS)
    Django 1.4
    

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21. With Arrival of v1.7
    1.7
 1.6.7
    1.6.6
    
    1.6.5
    
    1.6.4
    
    …
    
    1.6

    1.4.15
    1.4.14
    
    1.4.13
    
    1.4.12
    
    !
    1.4
    

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22. PREVIOUS DJANGO VERSIONS
    A TRIP DOWN MEMORY LANE
    

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23. 1.7
    1.6
    1.5 (Deprecations)
    1.4 (LTS)
    Relevant (Minor) Versions
    

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24. Django 1.4
    Timezone Support
    
    ORM Additions
    
    Cookie-Based Session Handling
    
    Auth Security
    
    Functional Browser Testing
    
    New Project Creation and Directory Structure
    

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25. Django 1.5
    Python 2.6+ (2.5 Dropped)
    
    Experimental Support for Python 3.2
    
    Custom Django User
    
    Generic Class-Based Views
    
    JSON
    

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26. Django 1.6
    Python 2.6+, Python 3.2
    
    Transactions
    
    Simpler, Smarter Defaults
    
    django-admin.py validate
    

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27. “Django 1.7 is shaping up to be

    the biggest Django release since 1.0.”
    – Russell Keith-Magee
    

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28. Django 1.7
    Migrations
    
    App Loading
    
    Static Systems Check
    
    Custom QuerySet
    
    Custom Lookups
    
    Prefetch
    

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29. 1.7
    DJANGO
    

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30. 2.7
    (AND 3.2+)
    PYTHON
    

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32. DJANGO 1.7
    COMPARING DJANGO 1.7 TO DJANGO 1.6
    CAMELOT!
    

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33. Django 1.7
    Migrations
    
    App Loading
    
    Static Systems Check
    

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36. $ django-admin.py startproject camelot # dj16
    !
    $ django-admin startproject camelot # dj17
    !
    !
    !
    /manage.py
    /camelot/
    __init__.py
    settings.py
    urls.py
    wsgi.py
    

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37. South in Django 1.6
    Best Practice: run syncdb now
    

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38. $ ./manage.py startapp roundtable
    !
    /camelot/roundtable/
    __init__.py
    admin.py
    migrations/
    __init.py__
    models.py
    tests.py
    views.py
    

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39. # roundtable/models.py
    !
    from django.db import models
    !
    !
    !
    !
    class Knight(models.Model):
    name = models.CharField(max_length=63)
    !
    def __str__(self):
    return self.name
    

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40. # roundtable/models.py
    from __future__ import unicode_literals
    from django.db import models
    from django.utils.encoding import
    python_2_unicode_compatible
    !
    @python_2_unicode_compatible
    class Knight(models.Model):
    name = models.CharField(max_length=63)
    !
    def __str__(self):
    return self.name
    

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41. Migrations History
    South
    
    Kickstarter
    

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42. What is a migration?
    Version Control for you database schema
    
    Migrations file are instructions for predictably
    altering the database
    
    Change model

    => create migrations file

    => migrate (alter) database
    

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43. South Migrations in
    Django 1.6
    

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44. Migrations in 1.6
    New Project Recommendations:
    
    Create project
    
    Add ‘south’, to settings.py
    
    Start with call to syncdb
    
    Create app
    

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45. $ ./manage.py schemamigration roundtable --initial
    Creating migrations directory at ‘camelot/
    roundtable/migrations'...
    Creating __init__.py in 'camelot/roundtable/
    migrations'...
    + Added model roundtable.Knight
    Created 0001_initial.py. You can now apply this
    migration with:
    ./manage.py migrate roundtable
    

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46. # roundtable/migrations/0001_initial.py
    # -*- coding: utf-8 -*-
    from south.utils import datetime_utils as datetime
    from south.db import db
    from south.v2 import SchemaMigration
    from django.db import models
    !
    !
    class Migration(SchemaMigration):
    !
    def forwards(self, orm): ...
    def backwards(self, orm): ...
    models = {...}
    complete_apps = ['roundtable']
    

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47. # roundtable/migrations/0001_initial.py
    from south.db import db
    !
    class Migration(SchemaMigration):
    !
    def forwards(self, orm):
    # Adding model 'Knight'
    db.create_table('roundtable_knight', (
    ('id',
    self.gf('django.db.models.fields.AutoField')
    (primary_key=True)),
    ('name',
    self.gf('django.db.models.fields.CharField')
    (max_length=63)),
    ))
    db.send_create_signal('roundtable', ['Knight'])
    

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48. # roundtable/migrations/0001_initial.py
    from south.db import db
    !
    class Migration(SchemaMigration):
    !
    def backwards(self, orm):
    # Deleting model 'Knight'
    db.delete_table('roundtable_knight')
    

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49. # roundtable/migrations/0001_initial.py
    class Migration(SchemaMigration):
    !
    models = {
    'roundtable.knight': {
    'Meta': {'object_name': 'Knight'},
    'id':
    ('django.db.models.fields.AutoField',
    [],
    {'primary_key': 'True'}),
    'name':
    ('django.db.models.fields.CharField',
    [],
    {'max_length': '63'})
    }
    }
    

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50. $ ./manage.py migrate roundtable 0001
    - Soft matched migration 0001 to 0001_initial.
    Running migrations for roundtable:
    - Migrating forwards to 0001_initial.
    > roundtable:0001_initial
    - Loading initial data for roundtable.
    Installed 0 object(s) from 0 fixture(s)
    

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51. >>> Knight.objects.bulk_create([
    ... Knight(name='Bedevere'),
    ... Knight(name='Bors'),
    ... Knight(name='Ector'),
    ... Knight(name='Galahad'),
    ... Knight(name='Gawain'),
    ... Knight(name='Lancelot'),
    ... Knight(name='Robin'),
    ... ])
    [, ,
    , ,
    , ,
    ]
    

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52. $ ./manage.py dumpdata --indent=2 roundtable > \
    > roundtable/fixtures/initial_data.json
    

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53. $ ./manage.py migrate roundtable zero
    

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54. # roundtable/migrations/0001_initial.py
    def backwards(self, orm):
    # Deleting model 'Knight'
    db.delete_table('roundtable_knight')
    

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55. $ ./manage.py migrate roundtable 0001
    - Soft matched migration 0001 to 0001_initial.
    Running migrations for roundtable:
    - Migrating forwards to 0001_initial.
    > roundtable:0001_initial
    - Loading initial data for roundtable.
    Installed 7 object(s) from 1 fixture(s)
    

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56. DAMN IT,
    LANCELOT
    

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57. # roundtable/models.py
    from __future__ import unicode_literals
    from django.db import models
    from django.utils.encoding import
    python_2_unicode_compatible
    !
    @python_2_unicode_compatible
    class Knight(models.Model):
    name = models.CharField(max_length=63)
    traitor = models.BooleanField()
    !
    def __str__(self):
    return self.name
    

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58. $ ./manage.py schemamigration roundtable --auto
    

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59. # roundtable/migrations/0001_initial.py
    models = {
    'roundtable.knight': {
    'Meta': {'object_name': 'Knight'},
    'id':
    ('django.db.models.fields.AutoField',
    [],
    {'primary_key': 'True'}),
    'name':
    ('django.db.models.fields.CharField',
    [],
    {'max_length': '63'})
    }
    }
    

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60. $ ./manage.py schemamigration roundtable --auto
    ? The field 'Knight.traitor' does not have a default
    specified, yet is NOT NULL.
    ? Since you are adding this field, you MUST specify a default
    ? value to use for existing rows. Would you like to:
    ? 1. Quit now, and add a default to the field in models.py
    ? 2. Specify a one-off value to use for existing columns now
    ? Please select a choice: 2
    ? Please enter Python code for your one-off default value.
    ? The datetime module is available, so you can do e.g.
    datetime.date.today()
    >>> False
    + Added field traitor on roundtable.Knight
    Created 0002_auto__add_field_knight_traitor.py.
    You can now apply this migration with:
    

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61. $ ./manage.py migrate roundtable
    

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62. View Slide

63. Step back!
    Delete:

    0002_auto__add_field_knight_traitor.py
    
    Remove:

    traitor = models.BooleanField()
    

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64. $ ./manage.py migrate roundtable zero
    !
    $ mv roundtable/fixtures/initial_data.json \
    roundtable/fixtures/0002_add_knight_data.json
    !
    $ ./manage.py migrate roundtable 0001
    - Soft matched migration 0001 to 0001_initial.
    Running migrations for roundtable:
    - Migrating forwards to 0001_initial.
    > roundtable:0001_initial
    - Loading initial data for roundtable.
    Installed 0 object(s) from 0 fixture(s)
    

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65. $ ./manage.py datamigration roundtable add_knight_data
    Created 0002_add_knight_data.py.
    

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66. # roundtable/migrations/0002_add_knight_data.py
    class Migration(DataMigration):
    !
    def forwards(self, orm):
    "Write your forwards methods here."
    !
    def backwards(self, orm):
    "Write your backwards methods here."
    

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67. # roundtable/migrations/0002_add_knight_data.py
    class Migration(SchemaMigration):
    !
    def forwards(self, orm):
    "Write your forwards methods here."
    from django.core.management import
    call_command
    call_command('loaddata',
    '0002_add_knight_data.json')
    

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68. # roundtable/migrations/0002_add_knight_data.py
    class Migration(SchemaMigration):
    !
    def forwards(self, orm):
    "Write your forwards methods here."
    orm.Knight.objects.bulk_create([
    orm.Knight(name='Bedevere'),
    orm.Knight(name='Bors'),
    orm.Knight(name='Ector'),
    orm.Knight(name='Galahad'),
    orm.Knight(name='Gawain'),
    orm.Knight(name='Lancelot'),
    orm.Knight(name='Robin'),
    ])
    

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69. $ ./manage.py migrate roundtable zero
    $ ./manage.py migrate roundtable
    Running migrations for roundtable:
    - Migrating forwards to 0002_add_knight_data.
    > roundtable:0001_initial
    > roundtable:0002_add_knight_data
    - Migration 'roundtable:0002_add_knight_data' is
    marked for no-dry-run.
    - Loading initial data for roundtable.
    Installed 0 object(s) from 0 fixture(s)
    

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70. # roundtable/migrations/0002_add_knight_data.py
    def backwards(self, orm):
    orm.Knight.objects.all().delete()
    

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71. $ ./manage.py migrate roundtable 0001
    - Soft matched migration 0001 to 0001_initial.
    Running migrations for roundtable:
    - Migrating backwards to just after 0001_initial.
    < roundtable:0002_add_knight_data
    - Migration 'roundtable:0002_add_knight_data' is
    marked for no-dry-run.
    

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72. >>> from roundtable.models import Knight
    >>> Knight.objects.all()
    []
    

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73. # roundtable/models.py
    class Knight(models.Model):
    ...
    traitor = models.BooleanField()
    

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74. $ ./manage.py schemamigration roundtable --auto
    ? The field 'Knight.traitor' does not have a default
    specified, yet is NOT NULL.
    ? Since you are adding this field, you MUST specify a
    default
    ? value to use for existing rows. Would you like to:
    ? 1. Quit now, and add a default to the field in models.py
    ? 2. Specify a one-off value to use for existing columns
    now
    ? Please select a choice: 2
    ? Please enter Python code for your one-off default value.
    ? The datetime module is available, so you can do e.g.
    datetime.date.today()
    >>> False
    + Added field traitor on roundtable.Knight
    Created 0003_auto__add_field_knight_traitor.py.
    You can now apply this migration with:
    ./manage.py migrate roundtable
    

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75. $ ./manage.py migrate roundtable
    Running migrations for roundtable:
    - Migrating forwards to
    0003_auto__add_field_knight_traitor.
    > roundtable:0002_add_knight_data
    - Migration 'roundtable:0002_add_knight_data' is
    marked for no-dry-run.
    > roundtable:0003_auto__add_field_knight_traitor
    - Loading initial data for roundtable.
    Installed 0 object(s) from 0 fixture(s)
    

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76. >>> from roundtable.models import Knight
    >>> Knight.objects.get(name__iexact="Lancelot").traitor
    False
    

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77. $ ./manage.py datamigration roundtable
    label_lancelot_traitor
    Created 0004_label_lancelot_traitor.py.
    

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78. # roundtable/migrations/0004_label_lancelot_traitor.py
    class Migration(DataMigration):
    !
    def forwards(self, orm):
    lancelot = orm.Knight.objects.get(
    name__iexact="Lancelot")
    lancelot.traitor = True
    lancelot.save()
    

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79. # roundtable/migrations/0004_label_lancelot_traitor.py
    class Migration(DataMigration):
    !
    def backwards(self, orm):
    lancelot = orm.Knight.objects.get(
    name__iexact="Lancelot")
    lancelot.traitor = False
    lancelot.save()
    

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80. $ ./manage.py migrate roundtable
    Running migrations for roundtable:
    - Migrating forwards to
    0004_label_lancelot_traitor.
    > roundtable:0004_label_lancelot_traitor
    - Migration 'roundtable:
    0004_label_lancelot_traitor' is marked for no-dry-
    run.
    - Loading initial data for roundtable.
    Installed 0 object(s) from 0 fixture(s)
    

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81. >>> from roundtable.models import Knight
    >>> Knight.objects.get(name__iexact="Lancelot").traitor
    True
    

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82. Django 1.7 Migrations
    

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83. $ django-admin startproject camelot
    $ cd camelot/
    $ ./manage.py startapp roundtable
    

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84. # roundtable/models.py
    from __future__ import unicode_literals
    from django.db import models
    from django.utils.encoding import
    python_2_unicode_compatible
    !
    @python_2_unicode_compatible
    class Knight(models.Model):
    name = models.CharField(max_length=63)
    !
    def __str__(self):
    return self.name
    

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85. $ ./manage.py makemigrations
    Migrations for 'roundtable':
    0001_initial.py:
    - Create model Knight
    

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86. # roundtable/migrations/0001_initial.py
    # -*- coding: utf-8 -*-
    from __future__ import unicode_literals
    from django.db import models, migrations
    !
    !
    class Migration(migrations.Migration):
    !
    dependencies = []
    operations = [...]
    

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87. # roundtable/migrations/0001_initial.py
    class Migration(migrations.Migration):
    !
    operations = [
    migrations.CreateModel(
    name='Knight',
    fields=[
    ('id',
    models.AutoField(
    primary_key=True,
    verbose_name='ID',
    serialize=False,
    auto_created=True)),
    ('name',
    models.CharField(
    max_length=63)),
    ],
    options={},
    bases=(models.Model,),
    ),
    ]
    

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88. $ ./manage.py migrate
    Operations to perform:
    Apply all migrations: auth, admin, contenttypes,
    roundtable, sessions
    Running migrations:
    Applying contenttypes.0001_initial... OK
    Applying auth.0001_initial... OK
    Applying admin.0001_initial... OK
    Applying roundtable.0001_initial... OK
    Applying sessions.0001_initial... OK
    

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89. $ ./manage.py makemigrations --empty roundtable
    Migrations for 'roundtable':
    0002_auto_20140903_1600.py:
    

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90. $ mv roundtable/migrations/0002_auto_20140903_1600.py \
    roundtable/migrations/0002_auto_add_knight_data.py
    

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91. # roundtable/migrations/0002_auto_add_knight_data.py
    !
    !
    !
    !
    !
    !
    !
    !
    !
    class Migration(migrations.Migration):
    ...
    operations = [
    !
    !
    !
    ]
    

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92. # roundtable/migrations/0002_auto_add_knight_data.py
    !
    def add_knight_data(apps, schema_editor):
    pass
    !
    !
    def remove_knight_data(apps, schema_editor):
    pass
    !
    !
    class Migration(migrations.Migration):
    ...
    operations = [
    migrations.RunPython(
    add_knight_data,
    reverse_code=remove_knight_data),
    ]
    

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93. # roundtable/migrations/0002_auto_add_knight_data.py
    from django.core.management import call_command
    !
    !
    def add_knight_data(apps, schema_editor):
    call_command('loaddata', 'knight_data.json')
    

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94. # roundtable/migrations/0002_auto_add_knight_data.py
    def add_knight_data(apps, schema_editor):
    Knight = apps.get_model('roundtable', 'Knight')
    Knight.objects.bulk_create([
    Knight(name='Bedevere'),
    Knight(name='Bors'),
    Knight(name='Ector'),
    Knight(name='Galahad'),
    Knight(name='Gawain'),
    Knight(name='Lancelot'),
    Knight(name='Robin'),
    ])
    

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95. # roundtable/migrations/0002_auto_add_knight_data.py
    def remove_knight_data(apps, schema_editor):
    Knight = apps.get_model('roundtable', 'Knight')
    Knight.objects.all().delete()
    

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96. DAMN IT
    LANCELOT
    (AGAIN)
    

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97. # roundtable/models.py
    from __future__ import unicode_literals
    from django.db import models
    from django.utils.encoding import
    python_2_unicode_compatible
    !
    @python_2_unicode_compatible
    class Knight(models.Model):
    name = models.CharField(max_length=63)
    traitor = models.BooleanField()
    !
    def __str__(self):
    return self.name
    

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98. $ ./manage.py check
    System check identified some issues:
    !
    WARNINGS:
    roundtable.Knight.traitor: (1_6.W002)
    BooleanField does not have a default value.
    HINT: Django 1.6 changed the default value
    of BooleanField from False to None.
    See [DOCS LINK] for more information.
    !
    System check identified 1 issue (0 silenced).
    

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99. $ ./manage.py makemigrations
    System check identified some issues:
    !
    WARNINGS: [Removed from Slides]
    You are trying to add a non-nullable field
    'traitor' to knight without a default;
    we can't do that (the database needs
    something to populate existing rows).
    Please select a fix:
    1) Provide a one-off default now
    (will be set on all existing rows)
    2) Quit, and let me add a default in models.py
    Select an option: 1
    Please enter the default value now, as valid Python
    The datetime module is available,
    so you can do e.g. datetime.date.today()
    

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100. >>> False
     Migrations for 'roundtable':
     0003_knight_traitor.py:
     - Add field traitor to knight
     

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101. $ ./manage.py migrate
     System check identified some issues:
     !
     WARNINGS:
     roundtable.Knight.traitor: (1_6.W002)
     BooleanField does not have a default value.
     HINT: Django 1.6 changed the default value of
     BooleanField from False to None.
     See [DOCS LINK] for more information.
     Operations to perform:
     Apply all migrations: auth, sessions,
     admin, roundtable,
     contenttypes
     Running migrations:
     Applying roundtable.0003_knight_traitor... OK
     

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102. Don’t Do That.
     Listen to check.
     

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103. # roundtable/models.py
     from __future__ import unicode_literals
     from django.db import models
     from django.utils.encoding import
     python_2_unicode_compatible
     !
     @python_2_unicode_compatible
     class Knight(models.Model):
     name = models.CharField(max_length=63)
     traitor = models.BooleanField(default=False)
     !
     def __str__(self):
     return self.name
     

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104. $ ./manage.py makemigrations
     $ ./manage.py migrate
     

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105. >>> from roundtable.models import Knight
     >>> Knight.objects.get(name__iexact="Lancelot").traitor
     False
     

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106. $ ./manage.py makemigrations --empty roundtable
     Migrations for 'roundtable':
     0004_auto_20140903_2045.py:
     

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107. $ mv roundtable/migrations/0004_auto_20140903_2045.py \
     roundtable/migrations/0004_label_lancelot_traitor.py
     

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108. # roundtable/migrations/0004_label_lancelot_traitor.py
     # -*- coding: utf-8 -*-
     from __future__ import unicode_literals
     from django.db import models, migrations
     !
     ...
     !
     class Migration(migrations.Migration):
     !
     dependencies = [
     ('roundtable', '0003_knight_traitor'),
     ]
     !
     operations = [
     migrations.RunPython(
     set_lancelot_traitor,
     reverse_code=unset_lancelot_traitor)
     ]
     

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109. # roundtable/migrations/0004_label_lancelot_traitor.py
     def set_lancelot_traitor(apps, schema_editor):
     Knight = apps.get_model('roundtable', 'Knight')
     lancelot = Knight.objects.get(
     name__iexact='Lancelot')
     lancelot.traitor = True
     lancelot.save()
     

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110. # roundtable/migrations/0004_label_lancelot_traitor.py
     def unset_lancelot_traitor(apps, schema_editor):
     Knight = apps.get_model('roundtable', 'Knight')
     lancelot = Knight.objects.get(
     name__iexact='Lancelot')
     lancelot.traitor = False
     lancelot.save()
     

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111. $ ./manage.py migrate
     

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112. >>> from roundtable.models import Knight
     >>> Knight.objects.get(name__iexact="Lancelot").traitor
     True
     

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113. REVIEW OF EXAMPLE
     

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114. Migrations
     

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115. Migrations in 1.7
     initial_data system deprecated
     
     Fixtures still valid
     
     Frozen Model gone
     

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116. View Slide

117. Migrations in 1.7
     Historical Model built and kept in memory
     
     Integrated with App Loader
     
     Utility of Dependency
     
     Caveat: Python Classes do not serialize!

     ModelA.save() will not be called.
     
     May be slow…
     

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118. Migrations in 1.7
     Workflow Identical
     
     change model
     
     create migration
     
     apply migration
     

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119. South will NOT run in 1.7
     
     Upgrade from South:
     
     Latest Migration
     
     Create Native
     
     Delete South
     
     Settings:
     
     MIGRATION_MODULES and
     SOUTH_MIGRATION_MODULES
     South and 1.7
     

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120. Legacy Behavior:

     rm -R appname/migrations/
     Remove Migrations
     

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121. App Loader
     

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122. App Cache
     Likened to Borg by Andrew Godwin
     
     Shared State
     
     Incompatible with migrations
     

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123. New App Registry
     Allow apps without a models module or package
     
     apps.get_model()
     app/apps.py
     Calls made in AppConfig
     
     admin.autodiscover()
     

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124. Systems Check
     

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125. Systems Check
     check in 1.6 verified settings
     
     response to 1.5 upgrade
     
     now extendable and modular
     
     validate deprecated
     
     (avoid confusion with field and forms
     
     use check
     

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126. from django.core.checks import register
     !
     @register('security')
     def my_check(app_configs, **kwargs):
     # ... perform checks, collect errors
     return errors
     

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127. Other Changes
     

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128. Customized ORM
     Interaction
     QuerySet
     
     objects = KnightQuerySet.as_manager()
     Lookups
     
     Prefetch object for prefetch_related()
     

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129. PREPARING TO UPGRADE
     

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130. View Slide

131. Upgrade Process
     Dependencies
     
     Release Notes
     
     Test Suite
     

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132. Upgrade Schedule
     Schedule Time for Upgrade
     
     Upgrade Early. Upgrade Often.
     
     Start with Release Candidate
     

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133. 1.0 1.1 1.2 1.3 1.4 1.5 1.6
     R² = 0.8733
     190d
     253d
     340d
     366d
     310d
     292d
     329d
     Duration Until Next Release Polynomial Regression (Order 3)
     Expected
     

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134. 1.0 1.1 1.2 1.3 1.4 1.5 1.6
     R² = 0.1971
     300d
     253d
     340d
     366d
     310d
     292d
     329d
     Duration Until Next Release Polynomial Regression (Order 3)
     Actual
     

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135. Practical Knowledge
     Django 1.7 means death of 1.5
     
     Django 1.5 has not been added to LTS support
     
     Django 1.4 has less than a year of support
     
     Migrate to Django 1.6 now
     

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136. Practical Upgrade
     Knowledge
     Iterate Through Versions
     
     Password Gotcha: base36 (1.5) -> base64 (1.6)
     
     syncdb is dead. Long live migrate
     
     Initial data fixtures are dead.

     Long live data migrations.
     
     Fields need deconstruct()
     

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137. The Future?
     LTS Status for 1.8?
     
     Look ahead at deprecations
     
     URL Configurations
     
     lists
     
     no patterns
     
     direct imports
     

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138. Thank you!
     (Dev Documentation)
     

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139. QUESTIONS?
     AFRG.CO/UPDJ17
     @ANDREWSFORGE
     ANDREWSFORGE.COM
     AFRG.CO/UPDJ17
     @ANDREWSFORGE
     ANDREWSFORGE.COM
     QUESTIONS?
     

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