Add REST create method that errors if a multi already exists.

r2/r2/controllers/multi.py

@@ -93,23 +93,21 @@ class MultiApiController(RedditController, OAuth2ResourceController):
         """Fetch a multi's data and subreddit list by name."""
         return self._format_multi(multi)
 
-    @require_oauth2_scope("subscribe")
-    @api_doc(api_section.multis, extends=GET_multi)
-    @validate(
-        VUser(),
-        VModhash(),
-        info=VMultiPath("multipath"),
-        data=VJSON("model"),
-    )
-    def PUT_multi(self, info, data):
-        """Create or update a multi."""
-        if info['username'].lower() != c.user.name.lower():
+    def _write_multi_data(self, path_info, data, fail_if_exists=False):
+        if path_info['username'].lower() != c.user.name.lower():
             raise RedditError('BAD_MULTI_NAME', code=400, fields="multipath")
 
         try:
-            multi = LabeledMulti._byID(info['path'])
+            multi = LabeledMulti._byID(path_info['path'])
         except tdb_cassandra.NotFound:
-            multi = LabeledMulti.create(info['path'], c.user)
+            multi = None
+
+        if multi:
+            if fail_if_exists:
+                raise RedditError('MULTI_EXISTS', code=409, fields="multipath")
+        else:
+            multi = LabeledMulti.create(path_info['path'], c.user)
+
 
         if 'visibility' in data:
             if data['visibility'] not in ('private', 'public'):
@@ -143,6 +141,32 @@ class MultiApiController(RedditController, OAuth2ResourceController):
                 raise RedditError('MULTI_TOO_MANY_SUBREDDITS', code=409)
 
         multi._commit()
+        return multi
+
+    @require_oauth2_scope("subscribe")
+    @api_doc(api_section.multis, extends=GET_multi)
+    @validate(
+        VUser(),
+        VModhash(),
+        path_info=VMultiPath("multipath"),
+        data=VJSON("model"),
+    )
+    def POST_multi(self, path_info, data):
+        """Create a multi. Responds with 409 Conflict if it already exists."""
+        multi = self._write_multi_data(path_info, data, fail_if_exists=True)
+        return self._format_multi(multi)
+
+    @require_oauth2_scope("subscribe")
+    @api_doc(api_section.multis, extends=GET_multi)
+    @validate(
+        VUser(),
+        VModhash(),
+        path_info=VMultiPath("multipath"),
+        data=VJSON("model"),
+    )
+    def PUT_multi(self, path_info, data):
+        """Create or update a multi."""
+        multi = self._write_multi_data(path_info, data)
         return self._format_multi(multi)
 
     @require_oauth2_scope("subscribe")

r2/r2/lib/errors.py

@@ -124,6 +124,7 @@ error_list = dict((
         ('BAD_MULTI_PATH', _('invalid multi path')),
         ('BAD_MULTI_NAME', _('%(reason)s')),
         ('MULTI_NOT_FOUND', _('that multireddit doesn\'t exist')),
+        ('MULTI_EXISTS', _('that multireddit already exists')),
         ('MULTI_CANNOT_EDIT', _('you can\'t change that multireddit')),
         ('MULTI_TOO_MANY_SUBREDDITS', _('no more space for subreddits in that multireddit')),
         ('MULTI_SPECIAL_SUBREDDIT', _("can't add special subreddit %(path)s")),

r2/r2/lib/strings.py

@@ -216,7 +216,6 @@ Note: there are a couple of places outside of your subreddit where someone can c
     create_multi = _('create a new multi'),
     awesomeness_goes_here = _('awesomeness goes here'),
     add_multi_sr = _('add a subreddit to your multi.'),
-    multi_already_exists = _('that multi already exists'),
 )
 
 class StringHandler(object):

r2/r2/public/static/js/multi.js

@@ -56,7 +56,8 @@ r.multi.MultiReddit = Backbone.Model.extend({
         return r.utils.joinURLs('/api/multi', this.id)
     },
 
-    initialize: function() {
+    initialize: function(attributes, options) {
+        this.uncreated = options && !!options.isNew
         this.subreddits = new r.multi.MultiRedditList(this.get('subreddits'))
         this.subreddits.url = this.url() + '/r/'
         this.on('change:subreddits', function(model, value) {
@@ -77,6 +78,21 @@ r.multi.MultiReddit = Backbone.Model.extend({
         return data
     },
 
+    isNew: function() {
+        return this.uncreated
+    },
+
+    sync: function(method, model, options) {
+        var res = Backbone.sync.apply(this, arguments)
+        if (method == 'create') {
+            res.done(_.bind(function() {
+                // upon successful creation, unset new flag
+                this.uncreated = false
+            }, this))
+        }
+        return res
+    },
+
     addSubreddit: function(name, options) {
         this.subreddits.create({name: name}, options)
     },
@@ -101,14 +117,6 @@ r.multi.MyMultiCollection = Backbone.Collection.extend({
         return model.get('path').toLowerCase()
     },
 
-    create: function(attributes, options) {
-        if ('name' in attributes) {
-            attributes['path'] = this.pathByName(attributes['name'])
-            delete attributes['name']
-        }
-        Backbone.Collection.prototype.create.call(this, attributes, options)
-    },
-
     parse: function(data) {
         return _.map(data, function(multiData) {
             return r.multi.multis.reify(multiData)
@@ -117,10 +125,6 @@ r.multi.MyMultiCollection = Backbone.Collection.extend({
 
     pathByName: function(name) {
         return '/user/' + r.config.logged + '/m/' + name
-    },
-
-    touchByName: function(name) {
-        return r.multi.multis.touch(this.pathByName(name))
     }
 })
 
@@ -306,7 +310,9 @@ r.multi.MultiDetails = Backbone.View.extend({
             el: $copyForm,
             navOnCreate: true,
             createMulti: _.bind(function(name) {
-                var newMulti = r.multi.mine.touchByName(name)
+                var newMulti = new r.multi.MultiReddit({
+                    path: r.multi.mine.pathByName(name)
+                }, {isNew: true})
                 this.model.copyTo(newMulti)
                 return newMulti
             }, this)
@@ -431,30 +437,25 @@ r.multi.MultiCreateForm = Backbone.View.extend({
         if (this.options.createMulti) {
             newMulti = this.options.createMulti(name)
         } else {
-            newMulti = r.multi.mine.touchByName(name)
+            var newMulti = new r.multi.MultiReddit({
+                path: r.multi.mine.pathByName(name)
+            }, {isNew: true})
         }
 
-        // check if the multi already exists
-        newMulti.fetch({beforeSend: this.showWorkingDeferred})
-            .done(_.bind(function() {
-                this.showError(r.strings('multi_already_exists'))
-            }, this))
-            .fail(_.bind(function() {
-                r.multi.mine.create(newMulti, {
-                    wait: true,
-                    beforeSend: this.showWorkingDeferred,
-                    success: _.bind(function(multi) {
-                        this.trigger('create', multi)
-                        if (this.options.navOnCreate) {
-                            window.location = multi.get('path') + '#created'
-                        }
-                    }, this),
-                    error: _.bind(function(multi, xhr) {
-                        var resp = JSON.parse(xhr.responseText)
-                        this.showError(resp.explanation)
-                    }, this)
-                })
-            }, this))
+        r.multi.mine.create(newMulti, {
+            wait: true,
+            beforeSend: this.showWorkingDeferred,
+            success: _.bind(function(multi) {
+                this.trigger('create', multi)
+                if (this.options.navOnCreate) {
+                    window.location = multi.get('path') + '#created'
+                }
+            }, this),
+            error: _.bind(function(multi, xhr) {
+                var resp = JSON.parse(xhr.responseText)
+                this.showError(resp.explanation)
+            }, this)
+        })
     },
 
     showError: function(error) {