Magnificent Migrations of Magical Majesty

core/server/data/fixtures/001.js

@@ -1,6 +1,5 @@
 var uuid = require('node-uuid');
 
-/*global module */
 module.exports = {
     posts: [
         {

core/server/data/fixtures/002.js

@@ -0,0 +1,22 @@
+var uuid = require('node-uuid');
+
+module.exports = {
+    posts: [],
+
+    settings: [
+        {
+            "uuid":         uuid.v4(),
+            "key":          "installedPlugins",
+            "value":        "[]",
+            "created_by":    1,
+            "updated_by":    1,
+            "type":         "core"
+        }
+    ],
+
+    roles: [],
+
+    permissions: [],
+
+    permissions_roles: []
+};

core/server/data/migration/002.js

@@ -0,0 +1,41 @@
+var when    = require('when'),
+    knex    = require('../../models/base').Knex,
+    migrationVersion = '002',
+    fixtures = require('../fixtures/' + migrationVersion),
+    errors = require('../../errorHandling'),
+    up,
+    down;
+
+up = function () {
+
+    return when.all([
+
+        // TODO: Create tables or modify tables in this general area
+
+    ]).then(function () {
+
+        // Once we create all of the initial tables, bootstrap any of the data
+
+        return when.all([
+            //knex('posts').insert(fixtures.posts),
+            //knex('roles').insert(fixtures.roles),
+            //knex('permissions').insert(fixtures.permissions),
+            //knex('permissions_roles').insert(fixtures.permissions_roles),
+            knex('settings').insert(fixtures.settings)
+        ]);
+
+    }).then(function () {
+
+        // Lastly, update the current version settings to reflect this version
+        return knex('settings')
+            .where('key', 'currentVersion')
+            .update({ 'value': migrationVersion });
+    });
+};
+
+down = function () {
+    return;
+};
+
+exports.up = up;
+exports.down = down;

core/server/data/migration/index.js

@@ -0,0 +1,90 @@
+
+var _ = require('underscore'),
+    when = require('when'),
+    series = require('when/sequence'),
+    errors = require('../../errorHandling'),
+    knex = require('../../models/base').Knex,
+    initialVersion = "001",
+    // This currentVersion string should always be the current version of Ghost,
+    // we could probably load it from the config file.
+    currentVersion = "002";
+
+module.exports = {
+    // Check for whether data is needed to be bootstrapped or not
+    init: function () {
+        var that = this;
+
+        return knex.Schema.hasTable('settings').then(function () {
+            // Check for the current version from the settings table
+            return knex('settings')
+                .where('key', 'currentVersion')
+                .select('value')
+                .then(function (currentVersionSetting) {
+                    // We are assuming here that the currentVersionSetting will 
+                    // always be less than the currentVersion value.
+                    if (currentVersionSetting === currentVersion) {
+                        return when.resolve();
+                    }
+
+                    // Bring the data up to the latest version
+                    return that.migrateFromVersion(currentVersion);
+                }, errors.logAndThrowError);
+
+        }, function () {
+            // If the settings table doesn't exist, bring everything up from initial version.
+            return that.migrateFromVersion(initialVersion);
+        });
+    },
+
+    // Migrate from a specific version to the latest
+    migrateFromVersion: function (version) {
+        var versions = [],
+            maxVersion = this.getVersionAfter(currentVersion),
+            currVersion = version,
+            tasks = [];
+
+        // Aggregate all the versions we need to do migrations for
+        while (currVersion !== maxVersion) {
+            versions.push(currVersion);
+            currVersion = this.getVersionAfter(currVersion);
+        }
+
+        // Aggregate all the individual up calls to use in the series(...) below
+        tasks = _.map(versions, function (taskVersion) {
+            return function () {
+                try {
+                    var migration = require('./' + taskVersion);
+                    return migration.up();
+                } catch (e) {
+                    errors.logError(e);
+                    return when.reject(e);
+                }
+            };
+        });
+
+        // Run each migration in series
+        return series(tasks);
+    },
+
+    // Get the following version based on the current
+    getVersionAfter: function (currVersion) {
+
+        var currVersionNum = parseInt(currVersion, 10),
+            nextVersion;
+
+        // Default to initialVersion if not parsed
+        if (isNaN(currVersionNum)) {
+            currVersionNum = parseInt(initialVersion, 10);
+        }
+
+        currVersionNum += 1;
+
+        nextVersion = String(currVersionNum);
+        // Pad with 0's until 3 digits
+        while (nextVersion.length < 3) {
+            nextVersion = "0" + nextVersion;
+        }
+
+        return nextVersion;
+    }
+};

core/server/models/index.js

@@ -1,6 +1,4 @@
-var GhostBookshelf = require('./base'),
-    errors = require('../errorHandling'),
-    knex = GhostBookshelf.Knex;
+var migrations = require('../data/migration');
 
 module.exports = {
     Post: require('./post').Post,
@@ -9,12 +7,6 @@ module.exports = {
     Permission: require('./permission').Permission,
     Settings: require('./settings').Settings,
     init: function () {
-        return knex.Schema.hasTable('posts').then(null, function () {
-            // Simple bootstraping of the data model for now.
-            var migration = require('../data/migration/001');
-            return migration.down().then(function () {
-                return migration.up();
-            }, errors.logAndThrowError);
-        }, errors.logAndThrowError);
+        return migrations.init();
     }
 };