rails db:schema:{dump,load} now checks ENV["SCHEMA_FORMAT"] before config

Since `rails db:structure:{dump,load}` was deprecated there wasn't a simple way to dump a schema to both SQL and Ruby formats. This PR implements @jeremy suggestion @ rails#39470 (review), so you can now do this with an environment variable. For example:

```
SCHEMA_FORMAT=sql rake db:schema:dump
```

Author: ghiculescu

activerecord/CHANGELOG.md

@@ -1,3 +1,15 @@
+*   `rails db:schema:{dump,load}` now checks `ENV["SCHEMA_FORMAT"]` before config
+
+    Since `rails db:structure:{dump,load}` was deprecated there wasn't a simple
+    way to dump a schema to both SQL and Ruby formats. You can now do this with
+    an environment variable. For example:
+
+    ```
+    SCHEMA_FORMAT=sql rake db:schema:dump
+    ```
+
+    *Alex Ghiculescu*
+
 *   Fixed MariaDB default function support.
 
     Defaults would be written wrong in "db/schema.rb" and not work correctly

activerecord/lib/active_record/railties/databases.rake

@@ -452,42 +452,45 @@ db_namespace = namespace :db do
   end
 
   namespace :schema do
-    desc "Creates a database schema file (either db/schema.rb or db/structure.sql, depending on `config.active_record.schema_format`)"
+    desc "Creates a database schema file (either db/schema.rb or db/structure.sql, depending on `ENV['SCHEMA_FORMAT']` or `config.active_record.schema_format`)"
     task dump: :load_config do
       ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
         if db_config.schema_dump
           ActiveRecord::Base.establish_connection(db_config)
-          ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config)
+          schema_format = ENV.fetch("SCHEMA_FORMAT", ActiveRecord.schema_format).to_sym
+          ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config, schema_format)
         end
       end
 
       db_namespace["schema:dump"].reenable
     end
 
-    desc "Loads a database schema file (either db/schema.rb or db/structure.sql, depending on `config.active_record.schema_format`) into the database"
+    desc "Loads a database schema file (either db/schema.rb or db/structure.sql, depending on `ENV['SCHEMA_FORMAT']` or `config.active_record.schema_format`) into the database"
     task load: [:load_config, :check_protected_environments] do
       ActiveRecord::Tasks::DatabaseTasks.load_schema_current(ActiveRecord.schema_format, ENV["SCHEMA"])
     end
 
     namespace :dump do
       ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |name|
-        desc "Creates a database schema file (either db/schema.rb or db/structure.sql, depending on `config.active_record.schema_format`) for #{name} database"
+        desc "Creates a database schema file (either db/schema.rb or db/structure.sql, depending on `ENV['SCHEMA_FORMAT']` or `config.active_record.schema_format`) for #{name} database"
         task name => :load_config do
           db_config = ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env, name: name)
           ActiveRecord::Base.establish_connection(db_config)
-          ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config)
+          schema_format = ENV.fetch("SCHEMA_FORMAT", ActiveRecord.schema_format).to_sym
+          ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config, schema_format)
           db_namespace["schema:dump:#{name}"].reenable
         end
       end
     end
 
     namespace :load do
       ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |name|
-        desc "Loads a database schema file (either db/schema.rb or db/structure.sql, depending on `config.active_record.schema_format`) into the #{name} database"
+        desc "Loads a database schema file (either db/schema.rb or db/structure.sql, depending on `ENV['SCHEMA_FORMAT']` or `config.active_record.schema_format`) into the #{name} database"
         task name => [:load_config, :check_protected_environments] do
           original_db_config = ActiveRecord::Base.connection_db_config
           db_config = ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env, name: name)
-          ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config)
+          schema_format = ENV.fetch("SCHEMA_FORMAT", ActiveRecord.schema_format).to_sym
+          ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config, schema_format)
         ensure
           ActiveRecord::Base.establish_connection(original_db_config) if original_db_config
         end
@@ -545,12 +548,13 @@ db_namespace = namespace :db do
       db_namespace["test:load_schema"].invoke
     end
 
-    # desc "Recreate the test database from an existent schema file (schema.rb or structure.sql, depending on `config.active_record.schema_format`)"
+    # desc "Recreate the test database from an existent schema file (schema.rb or structure.sql, depending on `ENV['SCHEMA_FORMAT']` or `config.active_record.schema_format`)"
     task load_schema: %w(db:test:purge) do
       should_reconnect = ActiveRecord::Base.connection_pool.active_connection?
       ActiveRecord::Schema.verbose = false
       ActiveRecord::Base.configurations.configs_for(env_name: "test").each do |db_config|
-        ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config)
+        schema_format = ENV.fetch("SCHEMA_FORMAT", ActiveRecord.schema_format).to_sym
+        ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config, schema_format)
       end
     ensure
       if should_reconnect
@@ -586,7 +590,8 @@ db_namespace = namespace :db do
           should_reconnect = ActiveRecord::Base.connection_pool.active_connection?
           ActiveRecord::Schema.verbose = false
           db_config = ActiveRecord::Base.configurations.configs_for(env_name: "test", name: name)
-          ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config)
+          schema_format = ENV.fetch("SCHEMA_FORMAT", ActiveRecord.schema_format).to_sym
+          ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config, schema_format)
         ensure
           if should_reconnect
             ActiveRecord::Base.establish_connection(ActiveRecord::Tasks::DatabaseTasks.env.to_sym)

railties/test/application/rake/dbs_test.rb

@@ -352,6 +352,15 @@ def db_schema_dump
         end
       end
 
+      def db_schema_sql_dump
+        Dir.chdir(app_path) do
+          args = ["generate", "model", "book", "title:string"]
+          rails args
+          rails "db:migrate", "db:schema:dump"
+          assert_match(/CREATE TABLE/, File.read("db/structure.sql"))
+        end
+      end
+
       test "db:schema:dump without database_url" do
         db_schema_dump
       end
@@ -361,7 +370,29 @@ def db_schema_dump
         db_schema_dump
       end
 
-      def db_schema_cache_dump(filename = "db/schema_cache.yml")
+      test "db:schema:dump with env as ruby" do
+        add_to_config "config.active_record.schema_format = :sql"
+
+        old_env = ENV["SCHEMA_FORMAT"]
+        ENV["SCHEMA_FORMAT"] = "ruby"
+
+        db_schema_dump
+      ensure
+        ENV["SCHEMA_FORMAT"] = old_env
+      end
+
+      test "db:schema:dump with env as sql" do
+        add_to_config "config.active_record.schema_format = :ruby"
+
+        old_env = ENV["SCHEMA_FORMAT"]
+        ENV["SCHEMA_FORMAT"] = "sql"
+
+        db_schema_sql_dump
+      ensure
+        ENV["SCHEMA_FORMAT"] = old_env
+      end
+
+      def db_schema_cache_dump
         Dir.chdir(app_path) do
           rails "db:schema:cache:dump"
 
@@ -398,7 +429,7 @@ def db_schema_cache_dump(filename = "db/schema_cache.yml")
         end
 
         db_schema_dump
-        db_schema_cache_dump("db/special_schema_cache.yml")
+        db_schema_cache_dump
       end
 
       test "db:schema:cache:dump custom env" do
@@ -407,7 +438,7 @@ def db_schema_cache_dump(filename = "db/schema_cache.yml")
         ENV["SCHEMA_CACHE"] = filename
 
         db_schema_dump
-        db_schema_cache_dump(filename)
+        db_schema_cache_dump
       ensure
         ENV["SCHEMA_CACHE"] = @old_schema_cache_env
       end