mediagoblin/db/indexes.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011 Free Software Foundation, Inc
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 """
  18 Indexes for the local database.
  19
  20 To add new indexes
  21 ------------------
  22
  23 Indexes are recorded in the following format:
  24
  25 ACTIVE_INDEXES = {
  26     'collection_name': {
  27         'identifier': {  # key identifier used for possibly deprecating later
  28             'index': [index_foo_goes_here]}}
  29
  30 ... and anything else being parameters to the create_index function
  31 (including unique=True, etc)
  32
  33 Current indexes must be registered in ACTIVE_INDEXES... deprecated
  34 indexes should be marked in DEPRECATED_INDEXES.
  35
  36 Remember, ordering of compound indexes MATTERS.  Read below for more.
  37
  38 REQUIRED READING:
  39  - http://kylebanker.com/blog/2010/09/21/the-joy-of-mongodb-indexes/
  40
  41  - http://www.mongodb.org/display/DOCS/Indexes
  42  - http://www.mongodb.org/display/DOCS/Indexing+Advice+and+FAQ
  43
  44
  45 To remove deprecated indexes
  46 ----------------------------
  47
  48 Removing deprecated indexes is the same, just move the index into the
  49 deprecated indexes mapping.
  50
  51 DEPRECATED_INDEXES = {
  52     'collection_name': {
  53         'deprecated_index_identifier1': {
  54             'index': [index_foo_goes_here]}}
  55
  56 ... etc.
  57
  58 If an index has been deprecated that identifier should NEVER BE USED
  59 AGAIN.  Eg, if you previously had 'awesomepants_unique', you shouldn't
  60 use 'awesomepants_unique' again, you should create a totally new name
  61 or at worst use 'awesomepants_unique2'.
  62 """
  63
  64 from pymongo import ASCENDING, DESCENDING
  65
  66
  67 ################
  68 # Active indexes
  69 ################
  70 ACTIVE_INDEXES = {}
  71
  72 # MediaEntry indexes
  73 # ------------------
  74
  75 MEDIAENTRY_INDEXES = {
  76     'uploader_slug_unique': {
  77         # Matching an object to an uploader + slug.
  78         # MediaEntries are unique on these two combined, eg:
  79         #   /u/${myuser}/m/${myslugname}/
  80         'index': [('uploader', ASCENDING),
  81                   ('slug', ASCENDING)],
  82         'unique': True},
  83
  84     'created': {
  85         # A global index for all media entries created, in descending
  86         # order.  This is used for the site's frontpage.
  87         'index': [('created', DESCENDING)]},
  88
  89     'uploader_created': {
  90         # Indexing on uploaders and when media entries are created.
  91         # Used for showing a user gallery, etc.
  92         'index': [('uploader', ASCENDING),
  93                   ('created', DESCENDING)]},
  94
  95     'state_uploader_tags_created': {
  96         # Indexing on processed?, media uploader, associated tags, and timestamp
  97         # Used for showing media items matching a tag search, most recent first.
  98         'index': [('state', ASCENDING),
  99                   ('uploader', ASCENDING),
 100                   ('tags.slug', DESCENDING),
 101                   ('created', DESCENDING)]},
 102
 103     'state_tags_created': {
 104         # Indexing on processed?, media tags, and timestamp (across all users)
 105         # This is used for a front page tag search.
 106         'index': [('state', ASCENDING),
 107                   ('tags.slug', DESCENDING),
 108                   ('created', DESCENDING)]}}
 109
 110
 111 ACTIVE_INDEXES['media_entries'] = MEDIAENTRY_INDEXES
 112
 113
 114 # User indexes
 115 # ------------
 116
 117 USER_INDEXES = {
 118     'username_unique': {
 119         # Index usernames, and make sure they're unique.
 120         # ... I guess we might need to adjust this once we're federated :)
 121         'index': 'username',
 122         'unique': True},
 123     'created': {
 124         # All most recently created users
 125         'index': 'created'}}
 126
 127
 128 ACTIVE_INDEXES['users'] = USER_INDEXES
 129
 130
 131 # MediaComment indexes
 132
 133 MEDIA_COMMENT_INDEXES = {
 134    'mediaentry_created': {
 135         'index': [('media_entry', ASCENDING),
 136                   ('created', DESCENDING)]}}
 137
 138 ACTIVE_INDEXES['media_comments'] = MEDIA_COMMENT_INDEXES
 139
 140
 141 ####################
 142 # Deprecated indexes
 143 ####################
 144
 145 DEPRECATED_INDEXES = {}