feat(defaultColumn): add conventions of default columns

Signed-off-by: Tobias Gurtzick <magic@wizardtales.com>

lib/executors/versioned/v2.js

@@ -8,6 +8,7 @@ const Chain = require('../../chain');
 const StateTravel = require('../../methods/v2/statetravel');
 const Migrate = require('../../methods/v2/migrate');
 const TranslateState = require('../../methods/v2/translatestate');
+const AddConventions = require('../../methods/v2/conventions');
 
 const execUnit = {
   _extend: (context, type) => {
@@ -28,6 +29,7 @@ const execUnit = {
   up: async function (context, driver, file) {
     const _file = file.get();
     const chain = new Chain(context._driver, file, driver, context.internals);
+    chain.addChain(AddConventions);
     chain.addChain(Learn);
     chain.addChain(StateTravel);
     chain.addChain(Migrate);

lib/methods/v2/conventions.js

@@ -0,0 +1,47 @@
+const Shadow = require('../../driver/shadow');
+
+class AddConventions {
+  constructor (internals, file, driver) {
+    this.file = file;
+    this.internals = internals;
+    this.driver = driver;
+    this._counter = 0;
+  }
+
+  createTable (t, d) {
+    d['__dbmigrate__flag'] = {
+      type: 'string'
+    };
+
+    return Promise.resolve();
+  }
+
+  createCollection (...args) {
+    return this.createTable.apply(this, args);
+  }
+}
+
+const noAction = prop => {
+  return function () {
+    return Promise.resolve();
+  };
+};
+
+module.exports = {
+  getInterface: (context, file, driver, internals) => {
+    if (context.conventions) {
+      const st = new AddConventions(internals, file, context);
+      return Shadow.overshadow(
+        driver,
+        Object.assign(st, context.conventions),
+        noAction
+      );
+    }
+
+    return Shadow.overshadow(
+      driver,
+      new AddConventions(internals, file, context),
+      noAction
+    );
+  }
+};