Add and document backup-related commands

docs/backup.md

@@ -0,0 +1,44 @@
+# Backups
+
+There are two important places where your data are located,
+in your database and in your media folder. The following `umap` commands
+might help you to backup these data:
+
+## `backup`
+
+The `backup` command requires a `path` as a parameter where two archives
+will be generated:
+
+* `<path>/database.<isodate>.tar.gz` contains a JSON dump of the database
+  ready to be passed to a `loaddata` command.
+* `<path>/media.<isodate>.tar.gz` contains the content of your media
+  folder as declared in your `MEDIA_ROOT` setting.
+
+### Examples
+
+```
+umap backup /tmp/test_backup
+```
+
+will generate (if run on May, 4th 2017!):
+
+```
+/tmp/test_backup/database.2017-05-04.tar.gz
+/tmp/test_backup/media.2017-05-04.tar.gz
+```
+
+## `sync_backup`
+
+The `sync_backup` command requires a `path` as a parameter and
+a `destination` to synchronize to.
+
+It will take both database and media archives files for the current day
+and `rsync` these to the destination.
+
+### Examples
+
+```
+umap sync_backup /tmp/test_backup root@ip:/backups
+```
+
+will sync generated files from the `backup` command to your distant server.

mkdocs.yml

@@ -5,4 +5,5 @@ pages:
 - Contributing: contributing.md
 - how-tos:
   - Ubuntu from scratch: ubuntu.md
+  - Backups and sync: backup.md
 theme: readthedocs

umap/management/commands/backup.py

@@ -0,0 +1,39 @@
+import os
+import tarfile
+from datetime import date
+from pathlib import Path
+
+from django.conf import settings
+from django.core.management import call_command
+from django.core.management.base import BaseCommand
+
+
+class Command(BaseCommand):
+    help = 'Backup database (postgresql) and geojsons.'
+
+    def add_arguments(self, parser):
+        parser.add_argument('path', help='Location of the backups.')
+
+    def archive(self, source, destination):
+        try:
+            archive = tarfile.open(str(destination), mode='w:gz')
+            archive.add(str(source), arcname='./', recursive=True,
+                        exclude=os.path.islink)
+        except:  # NOQA
+            raise
+        finally:
+            archive.close()
+
+    def handle(self, *args, **options):
+        today = date.today().isoformat()
+        root = Path(options['path'])
+        if not root.exists():
+            root.mkdir()
+        database_tmp = root.joinpath('database.{}.json'.format(today))
+        with database_tmp.open('w') as out:
+            call_command('dumpdata', format='json', stdout=out)
+        self.archive(database_tmp,
+                     root.joinpath('database.{}.tar.gz'.format(today)))
+        self.archive(settings.MEDIA_ROOT,
+                     root.joinpath('media.{}.tar.gz'.format(today)))
+        os.unlink(str(database_tmp))

umap/management/commands/sync_backup.py

@@ -0,0 +1,20 @@
+import subprocess
+from datetime import date
+from pathlib import Path
+
+from django.core.management.base import BaseCommand
+
+
+class Command(BaseCommand):
+    help = "Synchronize today's backup with whatever rsync-able."
+
+    def add_arguments(self, parser):
+        parser.add_argument('path', help='Location of the backups.')
+        parser.add_argument('destination', help='Destination of the backups.')
+
+    def handle(self, *args, **options):
+        today = date.today().isoformat()
+        root = Path(options['path'])
+        subprocess.call(
+            ['rsync', '-rv', str(root), '--include', '*{}*'.format(today),
+             options['destination']])