Add user avatars

app/models/user.rb

@@ -5,6 +5,12 @@ class User < ApplicationRecord
 
   serialize :preferences, UserPreferences
 
+  #
+  # File attachments
+  #
+
+  has_one_attached :avatar
+
   # Relations
   has_many :invitations, dependent: :destroy
   has_one  :invitation, inverse_of: :invitee, foreign_key: 'invited_user_id'
@@ -40,6 +46,7 @@ class User < ApplicationRecord
 
   validates_uniqueness_of :nostr_pubkey, allow_blank: true
 
+  validate :acceptable_avatar
   scope :confirmed,  -> { where.not(confirmed_at: nil) }
   scope :pending,    -> { where(confirmed_at: nil) }
   scope :all_except, -> (user) { where.not(id: user) }
@@ -140,6 +147,14 @@ class User < ApplicationRecord
     @display_name ||= ldap_entry[:display_name]
   end
 
+  def avatar_64px
+    avatar.variant(resize_to_fill: [64, 64])
+  end
+
+  def avatar_256px
+    avatar.variant(resize_to_fill: [256, 256])
+  end
+
   def services_enabled
     ldap_entry[:service] || []
   end
@@ -168,4 +183,17 @@ class User < ApplicationRecord
       return @ldap_service if defined?(@ldap_service)
       @ldap_service = LdapService.new
     end
+
+    def acceptable_avatar
+      return unless avatar.attached?
+
+      if avatar.blob.byte_size > 1.megabyte
+        errors.add(:avatar, "file size is too large")
+      end
+
+      acceptable_types = ["image/jpeg", "image/png"]
+      unless acceptable_types.include?(avatar.content_type)
+        errors.add(:avatar, "must be a JPEG or PNG file")
+      end
+    end
 end