def add_column(args, output):
" <app> <model> <column> [<column2> ...]: Add one or more columns"
if len(args) < 3:
raise CommandError(
'./manage.py migration addcolumn <app> <model> <column> '
'[<column2> ...]'
)
app_label, model, columns = args[0], args[1], args[2:]
actual_model = models.get_model(app_label, model)
style = no_style()
sql, references = connection.creation.sql_create_model(
actual_model, style, set()
)
col_specs = []
for column in columns:
is_foreign_key = isinstance(
actual_model._meta.get_field_by_name(column)[0], models.ForeignKey
)
col_specs.append((
column,
extract_column_spec(sql[0], column, is_foreign_key),
is_foreign_key
))
migration_defs = [
add_column_mtemplate % (app_label, model, column, col_spec)
for (column, col_spec, is_foreign_key) in col_specs
if not is_foreign_key
]
migration_fk_defs = [
add_column_foreignkey_mtemplate % (
app_label, model, column, col_spec,
actual_model._meta.get_field_by_name(column)[0].rel.to._meta.db_table
)
for (column, col_spec, is_foreign_key) in col_specs
if is_foreign_key
]
if migration_fk_defs:
print >>sys.stderr, """Warning!
You have added columns that are foreign keys (%s).
These will be added as nullable. If you need them to be NOT NULL, then you
have to write another migration to do that, after you've populated them
with data.""" % ','.join([column for (column, x, fk) in col_specs if fk])
migration_defs += migration_fk_defs
migration_output = migration_code(*migration_defs)
if len(columns) == 1:
migration_name = 'add_column_%s_to_%s_%s' % (
columns[0], app_label, model
)
else:
migration_name = 'add_columns_%s_to_%s_%s' % (
"_and_".join(columns), app_label, model
)
save_migration(output, migration_output, migration_name)
def add_new(args, output):
" <description>: Create empty migration (uses description in filename)"
if not args:
raise CommandError('./manage.py migration new <description>')
save_migration(
output, skeleton_template, '_'.join(args).lower()
)
def add_new(args, output):
" <description>: Create empty migration (uses description in filename)"
if not args:
raise CommandError('./manage.py migration new <description>')
db_engine = getattr(settings, 'DMIGRATIONS_DATABASE_BACKEND', 'mysql')
description = '_'.join(args).lower().replace('.', '_')
save_migration(
output, skeleton_template % db_engine, description
)
def add_insert(args, output):
" <app> <model>: Create insert migration for data in table"
if len(args) != 2:
raise CommandError('./manage.py migration insert <app> <model>')
app_label, model = args
table_name = '%s_%s' % (app_label, model)
def get_columns(table_name):
"Returns columns for table"
cursor = connection.cursor()
cursor.execute('describe %s' % table_name)
rows = cursor.fetchall()
cursor.close()
# Sanity check that first column is called 'id' and is primary key
first = rows[0]
assert first[0] == u'id', 'First column must be id'
assert first[3] == u'PRI', 'First column must be primary key'
return [r[0] for r in rows]
def get_dump(table_name):
"Returns {'table_name':..., 'columns':..., 'rows':...}"
columns = get_columns(table_name)
# Escape column names with `backticks` - so columns with names that
# match MySQL reserved words (e.g. "order") don't break things
escaped_columns = ['`%s`' % column for column in columns]
sql = 'SELECT %s FROM %s' % (', '.join(escaped_columns), table_name)
cursor = connection.cursor()
cursor.execute(sql)
rows = cursor.fetchall()
cursor.close()
return {
'table_name': table_name,
'columns': columns,
'rows': rows,
}
dump = get_dump(table_name)
migration_output = insert_mtemplate % {
'table_name': dump['table_name'],
'columns': repr(dump['columns']),
'insert_rows': pprint.pformat(dump['rows']),
'delete_ids': ', '.join(map(str, [r[0] for r in dump['rows']])),
}
migration_output = migration_code(migration_output)
save_migration(output, migration_output, 'insert_into_%s_%s' % (
app_label, model
))
def rename_table(args, output):
" <oldname> <newname>: Rename table"
if len(args) != 2:
raise CommandError('./manage.py dmigration renametable <oldname> <newname>')
oldname, newname = args
migration_output = 'm.RenameTable(%r, %r)' % (oldname, newname)
migration_output = migration_code(migration_output)
save_migration(output, migration_output, 'rename_table_%s_%s' % (
oldname, newname
))
def add_index(args, output):
" <app> <model> <column>: Add an index"
if len(args) != 3:
raise CommandError(
'./manage.py migration addindex <app> <model> <column>'
)
app_label, model, column = args
migration_output = add_index_mtemplate % (app_label, model, column)
migration_output = migration_code(migration_output)
save_migration(output, migration_output, 'add_index_%s_%s_%s' % (
app_label, model, column
))
def add_app(args, output):
" <app>: Add tables for a new application"
if len(args) != 1:
raise CommandError('./manage.py migration app <name-of-app>')
app_label = args[0]
app = models.get_app(app_label)
from django.core.management.sql import sql_create
up_sql = sql_create(app, no_style(), connections[DEFAULT_DB_ALIAS])
down_sql = sql_delete(app, no_style())
app_name = app.__name__.replace('.', '_')
migration_output = app_mtemplate % (
clean_up_create_sql(up_sql), clean_up_create_sql(down_sql)
)
migration_output = migration_code(migration_output)
save_migration(output, migration_output, app_name)
def add_table(args, output):
" <app> <model>: Add tables for a new model"
if len(args) != 2:
raise CommandError('./manage.py migration app <name-of-app>')
app_label, model = args
app = models.get_app(app_label)
app_name = app.__name__.replace('.', '_')
model_to_add = models.get_model(app_label, model)
if not model_to_add:
raise Exception("Model %s in app %s not found" % (model, app_label))
# The following code is a bit of a mess. I copied it from
# django.core.management.sql.sql_create without a full understanding of
# how it all works. Ideally this needs to refactored in Django itself to
# make it easier for libraries such as this one to reuse the table
# creation logic.
style = no_style()
app_models = models.get_models(app)
up_sql = []
tables = connection.introspection.table_names()
known_models = set([
model for model in connection.introspection.installed_models(tables)
])
pending_references = {}
sql_output, references = connection.creation.sql_create_model(
model_to_add, style, known_models
)
up_sql.extend(sql_output)
for refto, refs in references.items():
pending_references.setdefault(refto, []).extend(refs)
if refto not in known_models:
logging.warning('FK to %s, a model not backed by a db table.' % refto)
up_sql.extend(
connection.creation.sql_for_pending_references(
refto, style, pending_references
)
)
up_sql.extend(
connection.creation.sql_for_pending_references(
model, style, pending_references
)
)
# Keep track of the fact that we've created the table for this model.
known_models.add(model_to_add)
# Create the many-to-many join tables.
for field in model_to_add._meta.fields:
try:
table, deferred = connection.creation.sql_for_inline_many_to_many_references(model_to_add, field, style)
assert False, "It's not clear that this is working"
up_sql.extend(table)
except AttributeError:
pass
if not up_sql:
raise Exception("Model %s in app %s not found" % (model, app_label))
# Down sql just drops any tables we have created
down_sql = []
for sql in up_sql:
if sql.startswith('CREATE TABLE'):
down_sql.append('DROP TABLE %s;' % sql.split()[2])
# Reverse the order of down_sql
down_sql = down_sql[::-1]
migration_output = app_mtemplate % (
clean_up_create_sql(up_sql), clean_up_create_sql(down_sql)
)
migration_output = migration_code(migration_output)
save_migration(output, migration_output, app_name)
def add_column(args, output):
" <app> <model> <column> [<column2> ...]: Add one or more columns"
if len(args) < 3:
raise CommandError(
'./manage.py migration addcolumn <app> <model> <column> '
'[<column2> ...]'
)
app_label, model, columns = args[0], args[1], args[2:]
actual_model = models.get_model(app_label, model)
table_name = actual_model._meta.db_table
if actual_model is None:
raise CommandError(
'No such model %r, or it is not a concrete model.' % model
)
if table_name.startswith(app_label+'_'):
table_name = table_name[len(app_label)+1:]
style = no_style()
sql, references = connection.creation.sql_create_model(
actual_model, style, set()
)
col_specs = []
for column in columns:
is_foreign_key = isinstance(
actual_model._meta.get_field_by_name(column)[0], models.ForeignKey
)
col_specs.append((
column,
extract_column_spec(sql[0], column, is_foreign_key),
is_foreign_key
))
migration_defs = [
add_column_mtemplate % (app_label, table_name, column, col_spec)
for (column, col_spec, is_foreign_key) in col_specs
if not is_foreign_key
]
migration_fk_defs = [
add_column_foreignkey_mtemplate % (
app_label, model, column, col_spec,
actual_model._meta.get_field_by_name(column)[0].rel.to._meta.db_table
)
for (column, col_spec, is_foreign_key) in col_specs
if is_foreign_key
]
if migration_fk_defs:
print >>sys.stderr, """Warning!
You have added columns that are foreign keys (%s).
These will be added as nullable. If you need them to be NOT NULL, then you
have to write another migration to do that, after you've populated them
with data.""" % ','.join([column for (column, x, fk) in col_specs if fk])
migration_defs += migration_fk_defs
migration_output = migration_code(*migration_defs)
if len(columns) == 1:
migration_name = 'add_column_%s_to_%s_%s' % (
columns[0], app_label, model
)
else:
migration_name = 'add_columns_%s_to_%s_%s' % (
"_and_".join(columns), app_label, model
)
save_migration(output, migration_output, migration_name)