discourse/lib/migration/base_dropper.rb
Sam Saffron d0d5a138c3
DEV: stop freezing frozen strings
We have the `# frozen_string_literal: true` comment on all our
files. This means all string literals are frozen. There is no need
to call #freeze on any literals.

For files with `# frozen_string_literal: true`

```
puts %w{a b}[0].frozen?
=> true

puts "hi".frozen?
=> true

puts "a #{1} b".frozen?
=> true

puts ("a " + "b").frozen?
=> false

puts (-("a " + "b")).frozen?
=> true
```

For more details see: https://samsaffron.com/archive/2018/02/16/reducing-string-duplication-in-ruby
2020-04-30 16:48:53 +10:00

71 lines
2.0 KiB
Ruby

# frozen_string_literal: true
module Migration
class BaseDropper
FUNCTION_SCHEMA_NAME ||= "discourse_functions"
def self.create_readonly_function(table_name, column_name = nil)
DB.exec <<~SQL
CREATE SCHEMA IF NOT EXISTS #{FUNCTION_SCHEMA_NAME};
SQL
message = column_name ?
"Discourse: #{column_name} in #{table_name} is readonly" :
"Discourse: #{table_name} is read only"
DB.exec <<~SQL
CREATE OR REPLACE FUNCTION #{readonly_function_name(table_name, column_name)} RETURNS trigger AS $rcr$
BEGIN
RAISE EXCEPTION '#{message}';
END
$rcr$ LANGUAGE plpgsql;
SQL
end
def self.drop_readonly_function(table_name, column_name = nil)
DB.exec("DROP FUNCTION IF EXISTS #{readonly_function_name(table_name, column_name)} CASCADE")
end
def self.readonly_function_name(table_name, column_name = nil, with_schema: true)
function_name = [
"raise",
table_name,
column_name,
"readonly()"
].compact.join("_")
if with_schema && function_schema_exists?
"#{FUNCTION_SCHEMA_NAME}.#{function_name}"
else
function_name
end
end
def self.old_readonly_function_name(table_name, column_name = nil)
readonly_function_name(table_name, column_name).sub(
"#{FUNCTION_SCHEMA_NAME}.", ''
)
end
def self.readonly_trigger_name(table_name, column_name = nil)
[table_name, column_name, "readonly"].compact.join("_")
end
def self.function_schema_exists?
DB.exec(<<~SQL).to_s == '1'
SELECT schema_name
FROM information_schema.schemata
WHERE schema_name = '#{FUNCTION_SCHEMA_NAME}'
SQL
end
def self.existing_discourse_function_names
DB.query_single(<<~SQL)
SELECT routine_name
FROM information_schema.routines
WHERE routine_type = 'FUNCTION' AND specific_schema = '#{FUNCTION_SCHEMA_NAME}'
SQL
end
end
end