Add the ability to insert deferrable constraints after the table body

CHANGELOG.md

@@ -4,6 +4,16 @@
 
 * ...
 
+## 0.5.0    2025-07-09
+
+### Added
+* Introduced `:meta_tables_after_main` option as a more flexible replacement for `:indexes_after_tables`.  
+  This option places indexes and deferrable constraints after their respective `CREATE TABLE` statements.
+
+### Deprecated
+* `:indexes_after_tables` is now deprecated and will be removed in version 1.0.0.  
+  Please migrate to the new `:meta_tables_after_main` option.
+
 ## 0.4.3    2024-09-22
 
 * Fix additional regexp warnings from "rake test". [#50](https://github.com/lfittl/activerecord-clean-db-structure/pull/50)

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    activerecord-clean-db-structure (0.4.3)
+    activerecord-clean-db-structure (0.5.0)
       activerecord (>= 4.2)
 
 GEM

README.md

@@ -40,13 +40,13 @@ end
 
 ## Other options
 
-### indexes_after_tables
+### meta_tables_after_main
 
-You can optionally have indexes following the respective tables setting `indexes_after_tables`:
+You can optionally place indexes and constraints (limited to deferrable ones) after the main tables by setting meta_tables_after_main:
 
 ```ruby
 Rails.application.configure do
-  config.activerecord_clean_db_structure.indexes_after_tables = true
+  config.activerecord_clean_db_structure.meta_tables_after_main = true
 end
 ```
 
@@ -61,6 +61,7 @@ CREATE TABLE public.users (
 
 CREATE INDEX index_users_on_tentant_id ON public.users USING btree (tenant_id);
 CREATE UNIQUE INDEX index_users_on_email ON public.users USING btree (email);
+ALTER TABLE public.users ADD CONSTRAINT unique_tenant UNIQUE (tenant_id) DEFERRABLE INITIALLY DEFERRED;
 ```
 
 ### order_column_definitions

lib/activerecord-clean-db-structure/clean_dump.rb

@@ -128,17 +128,34 @@ def clean_options
         dump.gsub!(/^(INSERT INTO schema_migrations .*)\n\n/, "\\1\n")
       end
 
-      if options[:indexes_after_tables] == true
-        # Extract indexes, remove comments and place them just after the respective tables
+      # TODO: Remove support for :indexes_after_tables in version 1.0.0
+      if options[:indexes_after_tables]
+        warn "[DEPRECATION] The :indexes_after_tables option is deprecated and will be removed in version 1.0.0. Use :meta_tables_after_main instead."
+      end
+
+      if options[:indexes_after_tables] || options[:meta_tables_after_main]
+        # Extract indexes
         indexes =
           dump
             .scan(/^CREATE.+INDEX.+ON.+\n/)
             .group_by { |line| line.scan(/\b\w+\.\w+\b/).first }
             .transform_values(&:join)
 
+        # Extract deferrable constraints
+        deferrable_constraints =
+          dump
+            .scan(/^ALTER.+TABLE.+ONLY.+\n.+DEFERRABLE.+\n/)
+            .group_by { |line| line.scan(/\b\w+\.\w+\b/).first }
+            .transform_values(&:join)
+
+        # Remove indexes and deferrable constraints from the dump
         dump.gsub!(/^CREATE( UNIQUE)? INDEX \w+ ON .+\n+/, '')
         dump.gsub!(/^-- Name: \w+; Type: INDEX; Schema: \w+\n+/, '')
-        indexes.each do |table, indexes_for_table|
+
+        dump.gsub!(/^-- Name.+\n\nALTER.+TABLE.+ONLY.+\n.+DEFERRABLE.+\n+/, '')
+
+        indexes_and_constraints = indexes.merge(deferrable_constraints) { |_, v1, v2| v1 + v2 }
+        indexes_and_constraints.each do |table, indexes_for_table|
           dump.gsub!(/^(CREATE TABLE #{table}\b(:?[^;\n]*\n)+\);*\n(?:.*);*)/) { $1 + "\n\n" + indexes_for_table }
         end
       end

lib/activerecord-clean-db-structure/version.rb

@@ -1,3 +1,3 @@
 module ActiveRecordCleanDbStructure
-  VERSION = '0.4.3'
+  VERSION = '0.5.0'
 end

test/clean_dump_test.rb

@@ -17,8 +17,8 @@ def test_order_schema_migrations_values
     assert_cleans_dump "data/input.sql", "expectations/order_schema_migrations_values.sql", order_schema_migrations_values: true
   end
 
-  def test_indexes_after_tables
-    assert_cleans_dump "data/input.sql", "expectations/indexes_after_tables.sql", indexes_after_tables: true
+  def test_meta_tables_after_main
+    assert_cleans_dump "data/input.sql", "expectations/meta_tables_after_main.sql", meta_tables_after_main: true
   end
 
   def test_keep_extensions_all

test/data/input.sql

@@ -113,6 +113,11 @@ ALTER TABLE ONLY public.ar_internal_metadata
 ALTER TABLE ONLY public.delayed_jobs
     ADD CONSTRAINT delayed_jobs_pkey PRIMARY KEY (id);
 
+--
+-- Name: unique_locked_by_locked_at; Type: CONSTRAINT
+--
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
 
 --
 -- Name: schema_migrations schema_migrations_pkey; Type: CONSTRAINT; Schema: public; Owner: -

test/expectations/default_props.sql

@@ -46,6 +46,11 @@ CREATE TABLE public.schema_migrations (
 ALTER TABLE ONLY public.ar_internal_metadata
     ADD CONSTRAINT ar_internal_metadata_pkey PRIMARY KEY (key);
 
+-- Name: unique_locked_by_locked_at; Type: CONSTRAINT
+
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
+
 ALTER TABLE ONLY public.schema_migrations
     ADD CONSTRAINT schema_migrations_pkey PRIMARY KEY (version);
 

test/expectations/ignore_ids.sql

@@ -70,6 +70,11 @@ ALTER TABLE ONLY public.ar_internal_metadata
 ALTER TABLE ONLY public.delayed_jobs
     ADD CONSTRAINT delayed_jobs_pkey PRIMARY KEY (id);
 
+-- Name: unique_locked_by_locked_at; Type: CONSTRAINT
+
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
+
 -- Name: schema_migrations schema_migrations_pkey; Type: CONSTRAINT
 
 ALTER TABLE ONLY public.schema_migrations

test/expectations/keep_extensions_all.sql

@@ -52,6 +52,11 @@ CREATE TABLE public.schema_migrations (
 ALTER TABLE ONLY public.ar_internal_metadata
     ADD CONSTRAINT ar_internal_metadata_pkey PRIMARY KEY (key);
 
+-- Name: unique_locked_by_locked_at; Type: CONSTRAINT
+
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
+
 ALTER TABLE ONLY public.schema_migrations
     ADD CONSTRAINT schema_migrations_pkey PRIMARY KEY (version);
 

test/expectations/indexes_after_tables.sql → test/expectations/meta_tables_after_main.sql

@@ -40,6 +40,8 @@ WITH (fillfactor='85');
 CREATE INDEX index_delayed_jobs_on_locked_by ON public.delayed_jobs USING btree (locked_by);
 CREATE INDEX index_delayed_jobs_on_queue ON public.delayed_jobs USING btree (queue);
 CREATE INDEX index_delayed_jobs_on_run_at ON public.delayed_jobs USING btree (run_at) WHERE (locked_at IS NULL);
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
 
 -- Name: schema_migrations; Type: TABLE
 

test/expectations/order_column_definitions.sql

@@ -46,6 +46,11 @@ CREATE TABLE public.schema_migrations (
 ALTER TABLE ONLY public.ar_internal_metadata
     ADD CONSTRAINT ar_internal_metadata_pkey PRIMARY KEY (key);
 
+-- Name: unique_locked_by_locked_at; Type: CONSTRAINT
+
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
+
 ALTER TABLE ONLY public.schema_migrations
     ADD CONSTRAINT schema_migrations_pkey PRIMARY KEY (version);
 

test/expectations/order_schema_migrations_values.sql

@@ -46,6 +46,11 @@ CREATE TABLE public.schema_migrations (
 ALTER TABLE ONLY public.ar_internal_metadata
     ADD CONSTRAINT ar_internal_metadata_pkey PRIMARY KEY (key);
 
+-- Name: unique_locked_by_locked_at; Type: CONSTRAINT
+
+ALTER TABLE ONLY public.delayed_jobs
+    ADD CONSTRAINT unique_locked_by_locked_at UNIQUE (locked_by, locked_at) DEFERRABLE INITIALLY DEFERRED;
+
 ALTER TABLE ONLY public.schema_migrations
     ADD CONSTRAINT schema_migrations_pkey PRIMARY KEY (version);