fixup! Fix test suite.

Makefile

@@ -36,19 +36,18 @@ exec_test:
 		bundle exec rake db:seed[base]; \
 		bundle exec rake db:insert_script[base]; \
 		bundle exec rake db:flush[tmp]; \
+		rm -rf examples/suppliers-and-parts/data/tmp
 		bundle exec rake db:flush_empty[new_empty]; \
+		rm -rf examples/suppliers-and-parts/data/new_empty; \
 		bundle exec rake db:spy; \
 		bundle exec rake db:backup; \
 	'
 
-clean:
-	rm -rf examples/suppliers-and-parts/data/new_empty examples/suppliers-and-parts/data/tmp
-
 down:
 	docker stop db dbagent || true
 	docker network rm agent-network || true
 
-test: down prepare exec_test clean down
+test: down prepare exec_test down
 
 package:
 	bundle install

docker-compose.yml

@@ -11,4 +11,4 @@ services:
       POSTGRES_PASSWORD: dbagent
       POSTGRES_DB: suppliers-and-parts
     volumes:
-      - ./volumes/pgdata:/var/lib/postgresql/data
+      - .volumes/pgdata:/var/lib/postgresql/data

examples/multi-db/Dockerfile

@@ -0,0 +1,5 @@
+FROM enspirit/dbagent
+
+COPY initdb     /home/app/initdb
+COPY migrations /home/app/migrations
+COPY data       /home/app/data

examples/multi-db/README.md

@@ -0,0 +1,33 @@
+# Multiple databases managed through DbAgent
+
+This example provides a basic configuration to maintaing multiple databases
+on the same postgresql server.
+
+## Get started
+
+```
+docker-compose up
+```
+
+In another terminal, let migrate & spy the database:
+
+```
+docker-compose exec dbagent bash
+rake db:ping
+rake db:migrate
+rake db:spy
+```
+
+You can browse the database schema in a web browser:
+
+```
+http://127.0.0.1:8080/schema/
+```
+
+Let now install some data, then look at it:
+
+```
+echo "SELECT * FROM todo" | rake db:repl
+curl -X POST http://127.0.0.1/seeds/install -d "id=test"
+echo "SELECT * FROM todo" | rake db:repl
+```

examples/multi-db/data/base/db1/01-todo.json

@@ -0,0 +1,8 @@
+[
+  {
+    "id": 1,
+    "title": "Write more documenation",
+    "description": "Get started guide should probably be longer",
+    "done": false
+  }
+]

examples/multi-db/data/base/db1/metadata.json

@@ -0,0 +1 @@
+{ "inherits": "empty" }

examples/multi-db/data/empty/db1/01-todo.json

@@ -0,0 +1 @@
+[]

examples/multi-db/data/empty/db1/metadata.json

@@ -0,0 +1 @@
+{}

examples/multi-db/data/empty/db2/01-users.json

@@ -0,0 +1 @@
+[]

examples/multi-db/data/empty/db2/metadata.json

@@ -0,0 +1 @@
+{}

examples/multi-db/docker-compose.yml

@@ -0,0 +1,41 @@
+version: '2'
+
+services:
+
+  # The `postgres` agent is simply a PostgreSQL database. This agent may be
+  # replaced by a real database service, such as AWS RDS, provided the
+  # configuration of the other agents is adapted below.
+  #
+  # We keep the files in a mounted volume to keep the database state accross
+  # executions.
+  postgres:
+    image: postgres:15
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_DB: postgres
+      POSTGRES_PASSWORD: password
+    ports:
+      - 5432:5432
+    volumes:
+      - ./initdb:/docker-entrypoint-initdb.d
+      - ./volumes/pgdata:/var/lib/postgresql/data
+
+  # The `database` agent is the logical DbAgent tool. The agent is NOT intended to
+  # be started in production.
+  #
+  # Mounted volume is just a handy tool to hack on source code in development
+  # mode.
+  dbagent:
+    build: .
+    ports:
+      - 8080:80
+    volumes:
+      - ./backups:/home/app/backups
+      - ./migrations:/home/app/migrations
+      - ./data:/home/app/data
+      - ./schema:/home/app/schema
+    environment:
+      DBAGENT_HOST: postgres
+      DBAGENT_USER: postgres
+      DBAGENT_DB: postgres
+      DBAGENT_PASSWORD: password

examples/multi-db/initdb/multiple-databases.sql

@@ -0,0 +1,2 @@
+CREATE DATABASE db1;
+CREATE DATABASE db2;

examples/multi-db/migrations/db1/20250927120800_todo.rb

@@ -0,0 +1,11 @@
+Sequel.migration do
+  up do
+    run <<-SQL
+      CREATE TABLE todo (
+        id          SERIAL       NOT NULL,
+        title       VARCHAR(255) NOT NULL,
+        PRIMARY KEY (id)
+      );
+    SQL
+  end
+end

examples/multi-db/migrations/db2/20250927120800_users.rb

@@ -0,0 +1,11 @@
+Sequel.migration do
+  up do
+    run <<-SQL
+      CREATE TABLE users (
+        id          SERIAL       NOT NULL,
+        name        VARCHAR(255) NOT NULL,
+        PRIMARY KEY (id)
+      );
+    SQL
+  end
+end

examples/suppliers-and-parts/data/base/metadata.json

@@ -1 +1 @@
-{}
+{ "inherits": "empty" }

examples/suppliers-and-parts/data/hooks/child/metadata.json

@@ -0,0 +1 @@
+{ "inherits": "hooks" }

examples/suppliers-and-parts/data/hooks/metadata.json

@@ -0,0 +1 @@
+{ "inherits": "base" }

lib/db_agent/data_folder.rb

@@ -6,8 +6,8 @@ def initialize(db_handler)
     end
     attr_reader :db_handler
 
-    def seed_folder(seed)
-      SeedFolder.new(self, seed)
+    def seed_folder(seed, database = nil)
+      SeedFolder.new(self, seed, database)
     end
 
   end # class DataFolder

lib/db_agent/seed_folder.rb

@@ -2,8 +2,9 @@ module DbAgent
   class SeedFolder
     include SeedUtils
 
-    def initialize(data_folder, seed = 'empty')
+    def initialize(data_folder, seed = 'empty', database = nil)
       @data_folder = data_folder
+      @database = database
       @seed = seed
     end
     attr_reader :data_folder, :seed
@@ -12,13 +13,41 @@ def db_handler
       data_folder.db_handler
     end
 
+    def metadata
+      @metadata ||= (folder(seed)/"metadata.json").load
+    end
+
     def folder(seed = self.seed)
-      db_handler.data_folder/seed
+      if @database
+        db_handler.data_folder/seed/@database
+      else
+        db_handler.data_folder/seed
+      end
+    end
+
+    def parent
+      @parent ||= if inherits = metadata["inherits"]
+        SeedFolder.new(data_folder, inherits, @database)
+      else
+        NullObject.new(data_folder)
+      end
+    end
+
+    def before_seeding_files
+      f = (folder/'before_seeding.sql')
+      fs = f.file? ? [f] : []
+      parent.before_seeding_files + fs
+    end
+
+    def after_seeding_files
+      f = (folder/'after_seeding.sql')
+      fs = f.file? ? [f] : []
+      parent.after_seeding_files + fs
     end
 
     # Returns a Hash[Sequel.qualify(table_name) => Path]
     def seed_files_per_table
-      pairs = _seed_files_per_table(seed)
+      pairs = _seed_files_per_table
       pairs
         .keys
         .sort{|p1,p2|
@@ -29,23 +58,30 @@ def seed_files_per_table
         end
     end
 
-    def _seed_files_per_table(seed)
+    def _seed_files_per_table
       folder = self.folder(seed)
-      data = {}
-
-      # load metadata and install parent dataset if any
-      metadata = (folder/"metadata.json").load
-      if parent = metadata["inherits"]
-        data = _seed_files_per_table(parent)
-      end
+      map = parent._seed_files_per_table
 
       seed_files(folder).each do |f|
-        data[file2table(f)] = f
+        map[file2table(f)] = f
       end
 
-      data
+      map
     end
-    private :_seed_files_per_table
+    protected :_seed_files_per_table
+
+    class NullObject < SeedFolder
+      def _seed_files_per_table
+        {}
+      end
 
+      def before_seeding_files
+        []
+      end
+
+      def after_seeding_files
+        []
+      end
+    end
   end # class SeedFolder
 end # module DbAgent

lib/db_agent/seeder.rb

@@ -9,11 +9,11 @@ def initialize(handler)
     attr_reader :handler, :data_folder
 
     def install(from)
-      handler.sequel_db.transaction do
-        before_seeding!
+      seed_folder = data_folder.seed_folder(from)
+      seed_files = seed_folder.seed_files_per_table
 
-        seed_folder = data_folder.seed_folder(from)
-        seed_files = seed_folder.seed_files_per_table
+      handler.sequel_db.transaction do
+        before_seeding!(seed_folder)
 
         # Truncate tables
         seed_files.keys.reverse.each do |table|
@@ -111,17 +111,16 @@ def each_seed(install = true)
 
   private
 
-    def before_seeding!
-      file = handler.data_folder/"before_seeding.sql"
-      return unless file.exists?
-
-      handler.sequel_db.execute(file.read)
+    def before_seeding!(seed_folder)
+      seed_folder.before_seeding_files.each do |file|
+        handler.sequel_db.execute(file.read)
+      end
     end
 
-    def after_seeding!(seed_folder, folder = seed_folder.folder)
-      file = folder/"after_seeding.sql"
-      handler.sequel_db.execute(file.read) if file.exists?
-      after_seeding!(seed_folder, folder.parent) unless folder == handler.data_folder
+    def after_seeding!(seed_folder)
+      seed_folder.after_seeding_files.each do |file|
+        handler.sequel_db.execute(file.read)
+      end
     end
 
     def viewpoint