Add canonical e-mail blocks for suspended accounts (#16049)

Prevent new accounts from being created using the same underlying
e-mail as a suspended account using extensions and period
permutations. Stores e-mails as a SHA256 hash

2 files changed, 21 insertions, 1 deletions

diff --git a/db/migrate/20210416200740_create_canonical_email_blocks.rb b/db/migrate/20210416200740_create_canonical_email_blocks.rb
new file mode 100644
index 000000000..a1f1660bf
--- /dev/null
+++ b/db/migrate/20210416200740_create_canonical_email_blocks.rb
@@ -0,0 +1,10 @@
+class CreateCanonicalEmailBlocks < ActiveRecord::Migration[6.1]
+  def change
+    create_table :canonical_email_blocks do |t|
+      t.string :canonical_email_hash, null: false, default: '', index: { unique: true }
+      t.belongs_to :reference_account, null: false, foreign_key: { on_cascade: :delete, to_table: 'accounts' }
+
+      t.timestamps
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 599cd873b..dcbbf4aea 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2021_03_24_171613) do
+ActiveRecord::Schema.define(version: 2021_04_16_200740) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -280,6 +280,15 @@ ActiveRecord::Schema.define(version: 2021_03_24_171613) do
     t.index ["status_id"], name: "index_bookmarks_on_status_id"
   end
 
+  create_table "canonical_email_blocks", force: :cascade do |t|
+    t.string "canonical_email_hash", default: "", null: false
+    t.bigint "reference_account_id", null: false
+    t.datetime "created_at", precision: 6, null: false
+    t.datetime "updated_at", precision: 6, null: false
+    t.index ["canonical_email_hash"], name: "index_canonical_email_blocks_on_canonical_email_hash", unique: true
+    t.index ["reference_account_id"], name: "index_canonical_email_blocks_on_reference_account_id"
+  end
+
   create_table "conversation_mutes", force: :cascade do |t|
     t.bigint "conversation_id", null: false
     t.bigint "account_id", null: false
@@ -991,6 +1000,7 @@ ActiveRecord::Schema.define(version: 2021_03_24_171613) do
   add_foreign_key "blocks", "accounts", name: "fk_4269e03e65", on_delete: :cascade
   add_foreign_key "bookmarks", "accounts", on_delete: :cascade
   add_foreign_key "bookmarks", "statuses", on_delete: :cascade
+  add_foreign_key "canonical_email_blocks", "accounts", column: "reference_account_id"
   add_foreign_key "conversation_mutes", "accounts", name: "fk_225b4212bb", on_delete: :cascade
   add_foreign_key "conversation_mutes", "conversations", on_delete: :cascade
   add_foreign_key "custom_filters", "accounts", on_delete: :cascade