Refactor database interaction to use exec_query method and add schema…

… structure dump functionality

spec/schema_spec.cr

@@ -0,0 +1,9 @@
+require "./spec_helper"
+
+describe CQL::Schema do
+  it "dumps database structure" do
+    Example.dump_structure
+
+    File.exists?("db/structure.sql").should eq(true)
+  end
+end

src/delete.cr

@@ -43,7 +43,9 @@ module CQL
     # ```
     def commit
       query, params = to_sql
-      @schema.db.exec query, args: params
+      @schame.exec_query do |db|
+        db.exec query, args: params
+      end
     end
 
     # Generates the SQL query and parameters

src/insert.cr

@@ -60,7 +60,9 @@ module CQL
         # Reset to ensure nothing else but the :id is returned
         @back = Array(Expression::Column).new
         query, params = back(:id).to_sql
-        @schema.db.query_one(query, args: params, as: type)
+        @schame.exec_query do |db|
+          db.query_one(query, args: params, as: type)
+        end
       else
         commit.last_insert_id
       end
@@ -85,7 +87,9 @@ module CQL
     # ```
     def commit
       query, params = to_sql
-      @schema.db.exec(query, args: params)
+      @schame.exec_query do |db|
+        db.exec(query, args: params)
+      end
     rescue ex
       Log.error { "Insert failed: #{ex.message}" }
       raise ex

src/query.cr

@@ -66,7 +66,11 @@ module CQL
     # ```
     def all(as as_kind)
       query, params = to_sql
-      as_kind.from_rs @schema.db.query(query, args: params)
+      as_kind.from_rs
+
+      @schame.exec_query do |db|
+        db.query(query, args: params)
+      end
     end
 
     # - **@param** as [Type] The type to cast the results to
@@ -101,7 +105,9 @@ module CQL
     def first(as as_kind)
       query, params = to_sql
       Log.debug { "Query: #{query}, Params: #{params}" }
-      @schema.db.query_one(query, args: params, as: as_kind)
+      @schame.exec_query do |db|
+        db.query_one(query, args: params, as: as_kind)
+      end
     end
 
     # - **@param** as [Type] The type to cast the result to
@@ -133,7 +139,9 @@ module CQL
     # ```
     def get(as as_kind)
       query, params = to_sql
-      @schema.db.scalar(query, args: params, as: as_kind)
+      @schame.exec_query do |db|
+        db.scalar(query, args: params, as: as_kind)
+      end
     end
 
     # Iterates over each result and yields it to the provided block.
@@ -147,8 +155,10 @@ module CQL
     # ```
     def each(as as_kind, &)
       query, params = to_sql
-      @schema.db.query_each(query, args: params) do |result|
-        yield as_kind.from_rs(result)
+      @schame.exec_query do |db|
+        db.query_each(query, args: params) do |result|
+          yield as_kind.from_rs(result)
+        end
       end
     end
 

src/schema.cr

@@ -86,7 +86,6 @@ module CQL
     # schema = CQL::Schema.new(:northwind, "sqlite3://db.sqlite3")
     # ```
     def initialize(@name : Symbol, @uri : String, @adapter : Adapter = Adapter::SQLite, @version : String = "1.0")
-      @db = DB.connect(@uri)
       @gen = Expression::Generator.new(@adapter)
     end
 
@@ -114,10 +113,17 @@ module CQL
     # schema.exec("CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)")
     # ```
     def exec(sql : String)
-      @db.transaction do |tx|
-        cnn = tx.connection
-        cnn.exec(sql)
-      end
+      db = DB.open(@uri)
+      db.exec(sql)
+    ensure
+      db.close
+    end
+
+    def exec_query(&)
+      db = DB.open(@uri)
+      yield db
+    ensure
+      db.close
     end
 
     # Creates a new query for the schema.
@@ -234,7 +240,19 @@ module CQL
     # ```
     # schema.dump_structure("db/structure.sql")
     # ```
-    def dump_structure
+    def dump_structure(file = "db/structure.sql")
+      Dir.mkdir_p(File.dirname(file))
+
+      tables_structure = @tables.map do |_, table|
+        String.build do |str|
+          str << "-- Table: #{table.table_name}\n\n"
+          str << "-- Primary Key: #{table.primary.name} - Type: #{table.primary.type} \n\n"
+          str << table.create_sql
+          str << "\n\n"
+        end
+      end.join("\n")
+
+      File.write(file, tables_structure)
     end
 
     macro method_missing(call)

src/update.cr

@@ -48,7 +48,9 @@ module CQL
     # ```
     def commit
       query, params = to_sql
-      @schema.db.exec query, args: params
+      @schame.exec_query do |db|
+        db.exec query, args: params
+      end
     end
 
     # Generates the SQL query and parameters.