Merge 4405f15 into debd86f

AUTHORS

@@ -0,0 +1,13 @@
+The following people have contributed to django-postgres-copy
+
+Ben Welsh (palewire)
+Chaim Kirby (ckirby)
+James Gordon (gordonje)
+Ryan Murphy (rdmurphy)
+Magnum Leno (magnunleno)
+Yury Paykov (ojomio)
+Douglas Denhartog (denhartog)
+Michael Corey (mikejcorey)
+Jonathan Barratt (reduxionist)
+Daniel Cloud (dcloud)
+Jonathan Sundqvist (jonathan-s)

docs/index.rst

@@ -46,10 +46,22 @@ And here's how it exports a database table to a CSV.
 
     from myapp.models import MyModel
 
-
     MyModel.objects.to_csv("./data.csv")
 
 
+You can also use these methods standalone if you so need.
+
+.. code-block: python
+
+    from postgres_copy import from_csv
+    from myapp.models import MyModel
+
+    from_csv(MyModel, './data.csv', dict(name='NAME', number='NUMBER'))
+
+    query = MyModel.objects.all()
+    to_csv('./export.csv', query, db='default')
+
+
 Installation
 ============
 

postgres_copy/__init__.py

@@ -2,7 +2,7 @@
 # -*- coding: utf-8 -*-
 from .copy_from import CopyMapping
 from .copy_to import SQLCopyToCompiler, CopyToQuery
-from .managers import CopyManager, CopyQuerySet
+from .managers import CopyManager, CopyQuerySet, from_csv, to_csv
 __version__ = '2.3.0'
 
 
@@ -11,5 +11,7 @@
     'CopyMapping',
     'CopyQuerySet',
     'CopyToQuery',
-    'SQLCopyToCompiler'
+    'SQLCopyToCompiler',
+    'from_csv',
+    'to_csv'
 )

postgres_copy/copy_from.py

@@ -153,6 +153,7 @@ def validate_mapping(self):
 
         Raises errors if something goes wrong. Returns nothing if everything is kosher.
         """
+
         # Make sure all of the CSV headers in the mapping actually exist
         for map_header in self.mapping.values():
             if map_header not in self.headers:

postgres_copy/managers.py

@@ -131,6 +131,23 @@ def from_csv(self, csv_path, mapping=None, drop_constraints=True, drop_indexes=T
         """
         Copy CSV file from the provided path to the current model using the provided mapping.
         """
+        command = CopyCommand(self.model)
+        return command.from_csv(csv_path, mapping, drop_constraints, drop_indexes, silent, **kwargs)
+
+    def to_csv(self, csv_path, *fields, **kwargs):
+        """
+        Copy current QuerySet to CSV at provided path.
+        """
+        command = CopyCommand(self.model)
+        command.to_csv(csv_path, self.query, self.db, *fields, **kwargs)
+
+
+class CopyCommand(ConstraintQuerySet):
+
+    def __init__(self, model):
+        self.model = model
+
+    def from_csv(self, csv_path, mapping=None, drop_constraints=True, drop_indexes=True, silent=True, **kwargs):
         mapping = CopyMapping(self.model, csv_path, mapping, **kwargs)
 
         if drop_constraints:
@@ -147,16 +164,16 @@ def from_csv(self, csv_path, mapping=None, drop_constraints=True, drop_indexes=T
 
         return insert_count
 
-    def to_csv(self, csv_path, *fields, **kwargs):
+    def to_csv(self, csv_path, query, db, *fields, **kwargs):
         """
         Copy current QuerySet to CSV at provided path.
         """
         try:
             # For Django 2.0 forward
-            query = self.query.chain(CopyToQuery)
+            query = query.chain(CopyToQuery)
         except AttributeError:
             # For Django 1.11 backward
-            query = self.query.clone(CopyToQuery)
+            query = query.clone(CopyToQuery)
 
         # Get fields
         query.copy_to_fields = fields
@@ -173,8 +190,18 @@ def to_csv(self, csv_path, *fields, **kwargs):
         query.copy_to_null_string = "" if null_string is None else "NULL '{}'".format(null_string)
 
         # Run the query
-        compiler = query.get_compiler(self.db, connection=connection)
+        compiler = query.get_compiler(db, connection=connection)
         compiler.execute_sql(csv_path)
 
 
+def from_csv(model, csv_path, mapping=None, drop_constraints=True, drop_indexes=True, silent=True, **kwargs):
+    command = CopyCommand(model)
+    return command.from_csv(csv_path, mapping, drop_constraints, drop_indexes, silent, **kwargs)
+
+
+def to_csv(csv_path, query, db, *fields, **kwargs):
+    command = CopyCommand(query.model)
+    command.to_csv(csv_path, query.query, db, *fields, **kwargs)
+
+
 CopyManager = models.Manager.from_queryset(CopyQuerySet)

tests/tests.py

@@ -1,6 +1,10 @@
 import os
 import csv
 from datetime import date
+from django.test import TestCase
+from django.db.models import Count
+from django.core.exceptions import FieldDoesNotExist
+from django.conf import settings
 from .models import (
     MockObject,
     MockFKObject,
@@ -11,10 +15,8 @@
     HookedCopyMapping,
     SecondaryMockObject
 )
-from django.test import TestCase
-from django.db.models import Count
 from postgres_copy import CopyMapping
-from django.core.exceptions import FieldDoesNotExist
+from postgres_copy import from_csv, to_csv
 
 
 class BaseTest(TestCase):
@@ -186,6 +188,32 @@ def test_export_multi_db(self):
             items
         )
 
+class StandAloneTest(PostgresCopyToTest):
+
+    def setUp(self):
+        super(StandAloneTest, self).setUp()
+        self.export_path = os.path.join(os.path.dirname(__file__), 'export.csv')
+
+    def test_standalone_from_csv(self):
+        from_csv(MockObject, self.name_path, dict(name='NAME', number='NUMBER', dt='DATE'))
+
+        self.assertEqual(MockObject.objects.count(), 3)
+        self.assertEqual(MockObject.objects.get(name='BEN').number, 1)
+        self.assertEqual(
+            MockObject.objects.get(name='BEN').dt,
+            date(2012, 1, 1)
+        )
+
+    def test_standalone_to_csv(self):
+        self._load_objects(self.name_path)
+        to_csv(self.export_path, MockObject.objects.all(), 'default')
+        self.assertTrue(os.path.exists(self.export_path))
+        reader = csv.DictReader(open(self.export_path, 'r'))
+        self.assertTrue(
+            ['BEN', 'JOE', 'JANE'],
+            [i['name'] for i in reader]
+        )
+
 
 class PostgresCopyFromTest(BaseTest):