Separate initialize into its own module and write tests

src/server/plugins/__tests__/plugin_init.js

@@ -0,0 +1,77 @@
+import {values} from 'lodash';
+import expect from 'expect.js';
+import sinon from 'auto-release-sinon';
+import pluginInit from '../plugin_init';
+
+describe.only('Plugin init', () => {
+  const getPluginCollection = (plugins) => ({
+    byId: plugins,
+    toArray: () => values(plugins)
+  });
+
+  it('should call preInit before init', async () => {
+    const plugins = {
+      foo: {
+        id: 'foo',
+        init: sinon.spy(),
+        preInit: sinon.spy(),
+        requiredIds: []
+      },
+      bar: {
+        id: 'bar',
+        init: sinon.spy(),
+        preInit: sinon.spy(),
+        requiredIds: []
+      },
+      baz: {
+        id: 'baz',
+        init: sinon.spy(),
+        preInit: sinon.spy(),
+        requiredIds: []
+      }
+    };
+
+    await pluginInit(getPluginCollection(plugins));
+
+    expect(plugins.foo.preInit.calledBefore(plugins.foo.init)).to.be.ok();
+    expect(plugins.foo.preInit.calledBefore(plugins.bar.init)).to.be.ok();
+    expect(plugins.foo.preInit.calledBefore(plugins.baz.init)).to.be.ok();
+
+    expect(plugins.bar.preInit.calledBefore(plugins.foo.init)).to.be.ok();
+    expect(plugins.bar.preInit.calledBefore(plugins.bar.init)).to.be.ok();
+    expect(plugins.bar.preInit.calledBefore(plugins.baz.init)).to.be.ok();
+
+    expect(plugins.baz.preInit.calledBefore(plugins.foo.init)).to.be.ok();
+    expect(plugins.baz.preInit.calledBefore(plugins.bar.init)).to.be.ok();
+    expect(plugins.baz.preInit.calledBefore(plugins.baz.init)).to.be.ok();
+  });
+
+  it('should call preInits in correct order based on requirements', async () => {
+    const plugins = {
+      foo: {
+        id: 'foo',
+        init: sinon.spy(),
+        preInit: sinon.spy(),
+        requiredIds: ['bar', 'baz']
+      },
+      bar: {
+        id: 'bar',
+        init: sinon.spy(),
+        preInit: sinon.spy(),
+        requiredIds: []
+      },
+      baz: {
+        id: 'baz',
+        init: sinon.spy(),
+        preInit: sinon.spy(),
+        requiredIds: ['bar']
+      }
+    };
+
+    await pluginInit(getPluginCollection(plugins));
+
+    expect(plugins.bar.preInit.firstCall.calledBefore(plugins.foo.init.firstCall)).to.be.ok();
+    expect(plugins.bar.preInit.firstCall.calledBefore(plugins.baz.init.firstCall)).to.be.ok();
+    expect(plugins.baz.preInit.firstCall.calledBefore(plugins.foo.init.firstCall)).to.be.ok();
+  });
+});

src/server/plugins/initialize.js

@@ -1,4 +1,5 @@
-import { includes, keys } from 'lodash';
+import pluginInit from './plugin_init';
+
 module.exports = async function (kbnServer, server, config) {
 
   if (!config.get('plugins.initialize')) {
@@ -17,34 +18,5 @@ module.exports = async function (kbnServer, server, config) {
 
   });
 
-
-  let path = [];
-  const initialize = async function (id, fn) {
-    let plugin = plugins.byId[id];
-
-    if (includes(path, id)) {
-      throw new Error(`circular dependencies found: "${path.concat(id).join(' -> ')}"`);
-    }
-
-    path.push(id);
-
-    for (let reqId of plugin.requiredIds) {
-      if (!plugins.byId[reqId]) {
-        throw new Error(`Unmet requirement "${reqId}" for plugin "${id}"`);
-      }
-
-      await initialize(reqId, fn);
-    }
-
-    await plugin[fn]();
-    path.pop();
-  };
-
-  for (let {id} of plugins) {
-    await initialize(id, 'preInit');
-  }
-
-  for (let {id} of plugins) {
-    await initialize(id, 'init');
-  }
+  await pluginInit(plugins);
 };

src/server/plugins/plugin_init.js

@@ -0,0 +1,35 @@
+import { includes } from 'lodash';
+
+export default async (plugins) => {
+  let path = [];
+
+  const initialize = async function (id, fn) {
+    let plugin = plugins.byId[id];
+
+    if (includes(path, id)) {
+      throw new Error(`circular dependencies found: "${path.concat(id).join(' -> ')}"`);
+    }
+
+    path.push(id);
+
+    for (let reqId of plugin.requiredIds) {
+      if (!plugins.byId[reqId]) {
+        throw new Error(`Unmet requirement "${reqId}" for plugin "${id}"`);
+      }
+
+      await initialize(reqId, fn);
+    }
+
+    await plugin[fn]();
+    path.pop();
+  };
+
+  const collection = plugins.toArray();
+  for (let {id} of collection) {
+    await initialize(id, 'preInit');
+  }
+
+  for (let {id} of collection) {
+    await initialize(id, 'init');
+  }
+};