From b51eac30bed0cae62ad5745dd5a4d8176be88d56 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Thu, 9 Apr 2020 19:19:46 +0200
Subject: [PATCH 01/14] ADD logLever preset property && filter lower lever log
 messages

---
 lib/client-logger/package.json                |  4 +++-
 lib/client-logger/src/index.ts                | 21 +++++++++++++------
 lib/client-logger/src/typings.d.ts            |  1 +
 lib/core/src/server/common/common-preset.js   |  2 ++
 .../server/manager/manager-webpack.config.js  |  5 ++++-
 .../server/preview/iframe-webpack.config.js   |  5 ++++-
 6 files changed, 29 insertions(+), 9 deletions(-)
 create mode 100644 lib/client-logger/src/typings.d.ts

diff --git a/lib/client-logger/package.json b/lib/client-logger/package.json
index 8d672258bac7..2fcf320f9481 100644
--- a/lib/client-logger/package.json
+++ b/lib/client-logger/package.json
@@ -28,7 +28,9 @@
     "prepare": "node ../../scripts/prepare.js"
   },
   "dependencies": {
-    "core-js": "^3.0.1"
+    "core-js": "^3.0.1",
+    "global": "^4.3.2",
+    "loglevel": "^1.6.7"
   },
   "publishConfig": {
     "access": "public"
diff --git a/lib/client-logger/src/index.ts b/lib/client-logger/src/index.ts
index be814d8b8a76..6b1801055047 100644
--- a/lib/client-logger/src/index.ts
+++ b/lib/client-logger/src/index.ts
@@ -1,16 +1,25 @@
-const { console } = global;
-
-/* tslint:disable: no-console */
+import { window, LOGLEVEL } from 'global';
+import console from 'loglevel';
 
 export const logger = {
+  trace: (message: any, ...rest: any[]): void => console.trace(message, ...rest),
   debug: (message: any, ...rest: any[]): void => console.debug(message, ...rest),
-  log: (message: any, ...rest: any[]): void => console.log(message, ...rest),
+  log: (message: any, ...rest: any[]): void => window.console.log(message, ...rest),
   info: (message: any, ...rest: any[]): void => console.info(message, ...rest),
   warn: (message: any, ...rest: any[]): void => console.warn(message, ...rest),
   error: (message: any, ...rest: any[]): void => console.error(message, ...rest),
 };
 
-export const pretty = (type: keyof typeof logger) => (...args: string[]) => {
+if (LOGLEVEL) {
+  console.setLevel(LOGLEVEL);
+}
+
+// eslint-disable-next-line no-underscore-dangle
+window.__STORYBOOK_LOGGER = console;
+
+export const pretty = (type: 'trace' | 'debug' | 'info' | 'warn' | 'error') => (
+  ...args: string[]
+) => {
   const argArray = [];
 
   if (args.length) {
@@ -36,8 +45,8 @@ export const pretty = (type: keyof typeof logger) => (...args: string[]) => {
   console[type].apply(console, argArray);
 };
 
+pretty.trace = pretty('trace');
 pretty.debug = pretty('debug');
-pretty.log = pretty('log');
 pretty.info = pretty('info');
 pretty.warn = pretty('warn');
 pretty.error = pretty('error');
diff --git a/lib/client-logger/src/typings.d.ts b/lib/client-logger/src/typings.d.ts
new file mode 100644
index 000000000000..2f4eb9cf4fd9
--- /dev/null
+++ b/lib/client-logger/src/typings.d.ts
@@ -0,0 +1 @@
+declare module 'global';
diff --git a/lib/core/src/server/common/common-preset.js b/lib/core/src/server/common/common-preset.js
index 222a9127a75a..0d52a6e80df1 100644
--- a/lib/core/src/server/common/common-preset.js
+++ b/lib/core/src/server/common/common-preset.js
@@ -9,3 +9,5 @@ export const babel = async (_, options) => {
     presets.apply('babelDefault', babelConfig(options), options)
   );
 };
+
+export const logLevel = () => 'info';
diff --git a/lib/core/src/server/manager/manager-webpack.config.js b/lib/core/src/server/manager/manager-webpack.config.js
index a5251517eb9c..29d4ff3c36d8 100644
--- a/lib/core/src/server/manager/manager-webpack.config.js
+++ b/lib/core/src/server/manager/manager-webpack.config.js
@@ -21,7 +21,7 @@ import { resolvePathInStorybookCache } from '../utils/resolve-path-in-sb-cache';
 const coreDirName = path.dirname(require.resolve('@storybook/core/package.json'));
 const context = path.join(coreDirName, '../../node_modules');
 
-export default ({
+export default async ({
   configDir,
   configType,
   docsMode,
@@ -32,8 +32,10 @@ export default ({
   cache,
   previewUrl,
   versionCheck,
+  presets,
 }) => {
   const { raw, stringified } = loadEnv();
+  const logLevel = await presets.apply('logLevel', []);
   const isProd = configType === 'PRODUCTION';
   const refsTemplate = fse.readFileSync(path.join(__dirname, 'virtualModuleRef.template.js'), {
     encoding: 'utf8',
@@ -78,6 +80,7 @@ export default ({
           version,
           dlls: dll ? ['./sb_dll/storybook_ui_dll.js'] : [],
           globals: {
+            LOGLEVEL: JSON.stringify(logLevel),
             VERSIONCHECK: JSON.stringify(versionCheck),
             DOCS_MODE: docsMode, // global docs mode
             PREVIEW_URL: previewUrl, // global preview URL
diff --git a/lib/core/src/server/preview/iframe-webpack.config.js b/lib/core/src/server/preview/iframe-webpack.config.js
index 31be082b6252..eb49ebe3db33 100644
--- a/lib/core/src/server/preview/iframe-webpack.config.js
+++ b/lib/core/src/server/preview/iframe-webpack.config.js
@@ -39,6 +39,7 @@ export default async ({
   presets,
 }) => {
   const dlls = await presets.apply('webpackDlls', []);
+  const logLevel = await presets.apply('logLevel', []);
   const { raw, stringified } = loadEnv({ production: true });
   const babelLoader = createBabelLoader(babelOptions);
   const isProd = configType === 'PRODUCTION';
@@ -107,7 +108,9 @@ export default async ({
           files,
           options,
           version: packageJson.version,
-          globals: {},
+          globals: {
+            LOGLEVEL: JSON.stringify(logLevel),
+          },
           headHtmlSnippet: getPreviewHeadHtml(configDir, process.env),
           dlls,
           bodyHtmlSnippet: getPreviewBodyHtml(configDir, process.env),

From 24c44fc7d06e0523c9d20c68c64f0493a23d6968 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Fri, 10 Apr 2020 11:18:42 +0200
Subject: [PATCH 02/14] FIX lockfile

---
 yarn.lock | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/yarn.lock b/yarn.lock
index f4c43e741932..757b25b30e36 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -19631,7 +19631,7 @@ loglevel-plugin-prefix@^0.8.4:
   resolved "https://registry.yarnpkg.com/loglevel-plugin-prefix/-/loglevel-plugin-prefix-0.8.4.tgz#2fe0e05f1a820317d98d8c123e634c1bd84ff644"
   integrity sha512-WpG9CcFAOjz/FtNht+QJeGpvVl/cdR6P0z6OcXSkr8wFJOsV2GRj2j10JLfjuA4aYkcKCNIEqRGCyTife9R8/g==
 
-loglevel@^1.4.1, loglevel@^1.6.4, loglevel@^1.6.6:
+loglevel@^1.4.1, loglevel@^1.6.4, loglevel@^1.6.6, loglevel@^1.6.7:
   version "1.6.7"
   resolved "https://registry.yarnpkg.com/loglevel/-/loglevel-1.6.7.tgz#b3e034233188c68b889f5b862415306f565e2c56"
   integrity sha512-cY2eLFrQSAfVPhCgH1s7JI73tMbg9YC3v3+ZHVW67sBS7UxWzNEk/ZBbSfLykBWHp33dqqtOv82gjhKEi81T/A==

From db162891c2e5532e0ca8a51702d323e841760ac0 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Fri, 10 Apr 2020 11:48:29 +0200
Subject: [PATCH 03/14] FIX tests

---
 addons/links/src/preview.test.js               | 2 ++
 addons/links/src/react/components/link.test.js | 1 +
 app/react/src/client/preview/index.test.ts     | 2 +-
 lib/client-logger/src/index.test.ts            | 3 +++
 4 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/addons/links/src/preview.test.js b/addons/links/src/preview.test.js
index 04bdeb2730f1..48d4b3d77034 100644
--- a/addons/links/src/preview.test.js
+++ b/addons/links/src/preview.test.js
@@ -17,6 +17,8 @@ jest.mock('global', () => ({
       kind: 'kind',
     })),
   },
+  window: global,
+  __STORYBOOK_LOGGER: 'warn',
   __STORYBOOK_CLIENT_API__: {
     raw: jest.fn(() => [
       {
diff --git a/addons/links/src/react/components/link.test.js b/addons/links/src/react/components/link.test.js
index b38b6bf2bc9d..fd174ebe9d11 100644
--- a/addons/links/src/react/components/link.test.js
+++ b/addons/links/src/react/components/link.test.js
@@ -14,6 +14,7 @@ jest.mock('global', () => ({
       search: 'search',
     },
   },
+  window: global,
   __STORYBOOK_STORY_STORE__: {
     getSelection: jest.fn(() => ({ id: 1 })),
     fromId: jest.fn(() => ({})),
diff --git a/app/react/src/client/preview/index.test.ts b/app/react/src/client/preview/index.test.ts
index bd25fc3ca828..6bd053669e7e 100644
--- a/app/react/src/client/preview/index.test.ts
+++ b/app/react/src/client/preview/index.test.ts
@@ -18,7 +18,7 @@ describe('preview', () => {
       () =>
         ({
           document: undefined,
-          window: undefined,
+          window: {},
         } as any)
     );
     const api = require('.');
diff --git a/lib/client-logger/src/index.test.ts b/lib/client-logger/src/index.test.ts
index 0d2bc5782bcf..3272d11bf949 100644
--- a/lib/client-logger/src/index.test.ts
+++ b/lib/client-logger/src/index.test.ts
@@ -1,8 +1,11 @@
 import { logger } from '.';
 
+jest.mock('loglevel', () => global.console);
+
 describe('client-logger', () => {
   const initialConsole = { ...global.console };
   beforeEach(() => {
+    global.console.trace = jest.fn();
     global.console.debug = jest.fn();
     global.console.log = jest.fn();
     global.console.info = jest.fn();

From acc2de5551e6dc17bc61ddcec350192b0abd2585 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Mon, 13 Apr 2020 22:12:47 +0200
Subject: [PATCH 04/14] FIX

---
 addons/links/src/preview.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/addons/links/src/preview.test.js b/addons/links/src/preview.test.js
index 48d4b3d77034..88008541f0d2 100644
--- a/addons/links/src/preview.test.js
+++ b/addons/links/src/preview.test.js
@@ -18,7 +18,7 @@ jest.mock('global', () => ({
     })),
   },
   window: global,
-  __STORYBOOK_LOGGER: 'warn',
+  __STORYBOOK_LOGGER: console,
   __STORYBOOK_CLIENT_API__: {
     raw: jest.fn(() => [
       {

From 8cc33adef64f7162e13fc101a6d800e4d8ad6177 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Mon, 13 Apr 2020 22:14:56 +0200
Subject: [PATCH 05/14] Set correct initial value of logLevel

---
 lib/core/src/server/manager/manager-webpack.config.js | 2 +-
 lib/core/src/server/preview/iframe-webpack.config.js  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/core/src/server/manager/manager-webpack.config.js b/lib/core/src/server/manager/manager-webpack.config.js
index 29d4ff3c36d8..ed6fc3a4e992 100644
--- a/lib/core/src/server/manager/manager-webpack.config.js
+++ b/lib/core/src/server/manager/manager-webpack.config.js
@@ -35,7 +35,7 @@ export default async ({
   presets,
 }) => {
   const { raw, stringified } = loadEnv();
-  const logLevel = await presets.apply('logLevel', []);
+  const logLevel = await presets.apply('logLevel', 'info');
   const isProd = configType === 'PRODUCTION';
   const refsTemplate = fse.readFileSync(path.join(__dirname, 'virtualModuleRef.template.js'), {
     encoding: 'utf8',
diff --git a/lib/core/src/server/preview/iframe-webpack.config.js b/lib/core/src/server/preview/iframe-webpack.config.js
index eb49ebe3db33..b1a59db9bb84 100644
--- a/lib/core/src/server/preview/iframe-webpack.config.js
+++ b/lib/core/src/server/preview/iframe-webpack.config.js
@@ -39,7 +39,7 @@ export default async ({
   presets,
 }) => {
   const dlls = await presets.apply('webpackDlls', []);
-  const logLevel = await presets.apply('logLevel', []);
+  const logLevel = await presets.apply('logLevel', 'info');
   const { raw, stringified } = loadEnv({ production: true });
   const babelLoader = createBabelLoader(babelOptions);
   const isProd = configType === 'PRODUCTION';

From 2a5106c62038d9b13413cab7b3fb057e48bd2932 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Tue, 14 Apr 2020 00:02:15 +0200
Subject: [PATCH 06/14] ADD puppeteer as optionalDependency

---
 package.json |  3 ++-
 yarn.lock    | 16 ++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index c29369fd1a25..614c34b6b2e6 100644
--- a/package.json
+++ b/package.json
@@ -235,7 +235,8 @@
   },
   "optionalDependencies": {
     "@cypress/webpack-preprocessor": "^4.1.0",
-    "cypress": "^4.0.2"
+    "cypress": "^4.0.2",
+    "puppeteer": "^2.1.1"
   },
   "engines": {
     "node": ">=8.10.0",
diff --git a/yarn.lock b/yarn.lock
index ebe57ab1d521..8944bce24d73 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -24204,6 +24204,22 @@ puppeteer-core@2.1.1:
     rimraf "^2.6.1"
     ws "^6.1.0"
 
+puppeteer@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/puppeteer/-/puppeteer-2.1.1.tgz#ccde47c2a688f131883b50f2d697bd25189da27e"
+  integrity sha512-LWzaDVQkk1EPiuYeTOj+CZRIjda4k2s5w4MK4xoH2+kgWV/SDlkYHmxatDdtYrciHUKSXTsGgPgPP8ILVdBsxg==
+  dependencies:
+    "@types/mime-types" "^2.1.0"
+    debug "^4.1.0"
+    extract-zip "^1.6.6"
+    https-proxy-agent "^4.0.0"
+    mime "^2.0.3"
+    mime-types "^2.1.25"
+    progress "^2.0.1"
+    proxy-from-env "^1.0.0"
+    rimraf "^2.6.1"
+    ws "^6.1.0"
+
 purgecss@^1.4.0:
   version "1.4.2"
   resolved "https://registry.yarnpkg.com/purgecss/-/purgecss-1.4.2.tgz#67ab50cb4f5c163fcefde56002467c974e577f41"

From 13a2e29c4bc2456e325ba01d5425080630e6db0e Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Tue, 14 Apr 2020 01:05:36 +0200
Subject: [PATCH 07/14] FIX

---
 lib/cli/src/extract.js | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/lib/cli/src/extract.js b/lib/cli/src/extract.js
index 053b00338bec..3dc7d36f7561 100644
--- a/lib/cli/src/extract.js
+++ b/lib/cli/src/extract.js
@@ -79,13 +79,18 @@ const usePuppeteerBrowser = async () => {
   try {
     return await puppeteerCore.launch({ args });
   } catch (e) {
-    // it's not installed
-    logger.info('installing puppeteer...');
     return new Promise((resolve, reject) => {
+      // it's not installed
+      const l = () => logger.info('installing puppeteer...');
+      const timer = setInterval(l, 20000);
+      l();
       // eslint-disable-next-line global-require
       require('child_process').exec(
         `node ${require.resolve(path.join('puppeteer-core', 'install.js'))}`,
-        (error) => (error ? reject(error) : resolve(puppeteerCore.launch({ args })))
+        (error) => {
+          clearInterval(timer);
+          return error ? reject(error) : resolve(puppeteerCore.launch({ args }));
+        }
       );
     });
   }

From da6b2307e9142dd7a8243417573dbf374ad4011f Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Tue, 14 Apr 2020 01:37:57 +0200
Subject: [PATCH 08/14] FIX

---
 lib/cli/src/extract.js | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/lib/cli/src/extract.js b/lib/cli/src/extract.js
index 3dc7d36f7561..273e921c74ef 100644
--- a/lib/cli/src/extract.js
+++ b/lib/cli/src/extract.js
@@ -12,7 +12,8 @@ const read = async (url) => {
   await page.goto(url);
 
   await page.waitForFunction(
-    'window.__STORYBOOK_STORY_STORE__ && window.__STORYBOOK_STORY_STORE__.extract && window.__STORYBOOK_STORY_STORE__.extract()'
+    'window.__STORYBOOK_STORY_STORE__ && window.__STORYBOOK_STORY_STORE__.extract && window.__STORYBOOK_STORY_STORE__.extract()',
+    { timeout: 120000, polling: 'mutation' }
   );
   const data = JSON.parse(
     await page.evaluate(async () => {
@@ -81,14 +82,12 @@ const usePuppeteerBrowser = async () => {
   } catch (e) {
     return new Promise((resolve, reject) => {
       // it's not installed
-      const l = () => logger.info('installing puppeteer...');
-      const timer = setInterval(l, 20000);
-      l();
+      logger.info('installing puppeteer...');
+
       // eslint-disable-next-line global-require
       require('child_process').exec(
         `node ${require.resolve(path.join('puppeteer-core', 'install.js'))}`,
         (error) => {
-          clearInterval(timer);
           return error ? reject(error) : resolve(puppeteerCore.launch({ args }));
         }
       );

From d550600b0142f1db593645eaef16926d0358e064 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Thu, 14 May 2020 11:04:53 +0200
Subject: [PATCH 09/14] ADD a loglevel option for dev mode in CLI

it's not used anywhere I think, but we're getting quite a few 'invalid cli option' errors,
and this should get rid of them.
---
 lib/core/src/server/cli/dev.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/core/src/server/cli/dev.js b/lib/core/src/server/cli/dev.js
index ab37a045b608..a4e14b5d5cfd 100644
--- a/lib/core/src/server/cli/dev.js
+++ b/lib/core/src/server/cli/dev.js
@@ -25,6 +25,7 @@ async function getCLI(packageJson) {
     .option('--ssl-key <key>', 'Provide an SSL key. (Required with --https)')
     .option('--smoke-test', 'Exit after successful start')
     .option('--ci', "CI mode (skip interactive prompts, don't open browser)")
+    .option('--loglevel [level]', 'Control level of logging during build')
     .option('--quiet', 'Suppress verbose build output')
     .option('--no-version-updates', 'Suppress update check', true)
     .option('--no-dll', 'Do not use dll reference')

From 05e2cf0ba85bd25a7343736bd6872fdf951fd8d7 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Tue, 26 May 2020 13:52:01 +0200
Subject: [PATCH 10/14] FIX loglevel being a string within a string

---
 lib/core/src/server/manager/manager-webpack.config.js | 2 +-
 lib/core/src/server/preview/iframe-webpack.config.js  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/core/src/server/manager/manager-webpack.config.js b/lib/core/src/server/manager/manager-webpack.config.js
index 9eb0831ad540..49fe2f0f8a5a 100644
--- a/lib/core/src/server/manager/manager-webpack.config.js
+++ b/lib/core/src/server/manager/manager-webpack.config.js
@@ -83,7 +83,7 @@ export default async ({
           version,
           dlls: dll ? ['./sb_dll/storybook_ui_dll.js'] : [],
           globals: {
-            LOGLEVEL: JSON.stringify(logLevel),
+            LOGLEVEL: logLevel,
             VERSIONCHECK: JSON.stringify(versionCheck),
             DOCS_MODE: docsMode, // global docs mode
             PREVIEW_URL: previewUrl, // global preview URL
diff --git a/lib/core/src/server/preview/iframe-webpack.config.js b/lib/core/src/server/preview/iframe-webpack.config.js
index 24b4eba53932..55cc95d8accd 100644
--- a/lib/core/src/server/preview/iframe-webpack.config.js
+++ b/lib/core/src/server/preview/iframe-webpack.config.js
@@ -114,7 +114,7 @@ export default async ({
           options,
           version: packageJson.version,
           globals: {
-            LOGLEVEL: JSON.stringify(logLevel),
+            LOGLEVEL: logLevel,
           },
           headHtmlSnippet: getPreviewHeadHtml(configDir, process.env),
           dlls,

From 8b4a7e237b728ecff8b37775125af8498724d169 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Tue, 26 May 2020 16:00:01 +0200
Subject: [PATCH 11/14] FIX lockfile && safety check for window

---
 lib/client-logger/src/index.ts | 6 ++++--
 yarn.lock                      | 6 +-----
 2 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/lib/client-logger/src/index.ts b/lib/client-logger/src/index.ts
index 6b1801055047..6dedb9df4991 100644
--- a/lib/client-logger/src/index.ts
+++ b/lib/client-logger/src/index.ts
@@ -14,8 +14,10 @@ if (LOGLEVEL) {
   console.setLevel(LOGLEVEL);
 }
 
-// eslint-disable-next-line no-underscore-dangle
-window.__STORYBOOK_LOGGER = console;
+if (window) {
+  // eslint-disable-next-line no-underscore-dangle
+  window.__STORYBOOK_LOGGER = console;
+}
 
 export const pretty = (type: 'trace' | 'debug' | 'info' | 'warn' | 'error') => (
   ...args: string[]
diff --git a/yarn.lock b/yarn.lock
index a608e008471a..e96b3b960a64 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -21656,11 +21656,7 @@ loglevel-plugin-prefix@^0.8.4:
   resolved "https://registry.yarnpkg.com/loglevel-plugin-prefix/-/loglevel-plugin-prefix-0.8.4.tgz#2fe0e05f1a820317d98d8c123e634c1bd84ff644"
   integrity sha512-WpG9CcFAOjz/FtNht+QJeGpvVl/cdR6P0z6OcXSkr8wFJOsV2GRj2j10JLfjuA4aYkcKCNIEqRGCyTife9R8/g==
 
-<<<<<<< HEAD
-loglevel@^1.4.1, loglevel@^1.6.4, loglevel@^1.6.6, loglevel@^1.6.7:
-=======
-loglevel@^1.4.1, loglevel@^1.6.4, loglevel@^1.6.6, loglevel@^1.6.8:
->>>>>>> next
+loglevel@^1.4.1, loglevel@^1.6.4, loglevel@^1.6.6, loglevel@^1.6.7, loglevel@^1.6.8:
   version "1.6.8"
   resolved "https://registry.yarnpkg.com/loglevel/-/loglevel-1.6.8.tgz#8a25fb75d092230ecd4457270d80b54e28011171"
   integrity sha512-bsU7+gc9AJ2SqpzxwU3+1fedl8zAntbtC5XYlt3s2j1hJcn2PsXSmgN8TaLG/J1/2mod4+cE/3vNL70/c1RNCA==

From b26e8c1790b15574dd40438b42944083f3f2daa0 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Fri, 29 May 2020 12:13:32 +0200
Subject: [PATCH 12/14] ADD docs

---
 docs/src/pages/configurations/overview/index.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/src/pages/configurations/overview/index.md b/docs/src/pages/configurations/overview/index.md
index 0c8de1bc57d6..5c9de8814fb8 100644
--- a/docs/src/pages/configurations/overview/index.md
+++ b/docs/src/pages/configurations/overview/index.md
@@ -26,6 +26,8 @@ module.exports = {
 
 `stories` is a list of [glob](https://www.npmjs.com/package/glob) patterns that tells where your stories are located, relative to the configuration file.
 
+`logLevel` is a setting that tells storybook to only log to a specific level. Options are: `trace`, `debug`, `info`, `warn`, `error` and `silent`.
+
 The `addons` field can refer to traditional [addons](../../addons/introduction), but it can also include [presets](/docs/presets/introduction/), which are able to extend the config further.
 
 ### `main.js` is a  Preset

From c604b2626b70bbd0ddbd38fe61242a9ff79690c1 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Fri, 29 May 2020 12:31:07 +0200
Subject: [PATCH 13/14] set loglevel for node based on cli param in dev-mode

---
 lib/core/src/server/cli/dev.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/core/src/server/cli/dev.js b/lib/core/src/server/cli/dev.js
index a4e14b5d5cfd..050b4f9de5b5 100644
--- a/lib/core/src/server/cli/dev.js
+++ b/lib/core/src/server/cli/dev.js
@@ -37,6 +37,8 @@ async function getCLI(packageJson) {
     .option('--docs', 'Build a documentation-only site using addon-docs')
     .parse(process.argv);
 
+  logger.setLevel(program.loglevel);
+
   // Workaround the `-h` shorthand conflict.
   // Output the help if `-h` is called without any value.
   // See storybookjs/storybook#5360

From 7078a12921faf235764b74f40504d5a2b79497b1 Mon Sep 17 00:00:00 2001
From: Norbert de Langen <ndelangen@me.com>
Date: Fri, 29 May 2020 12:31:31 +0200
Subject: [PATCH 14/14] Use cli param to set default loglevel in preset

---
 lib/core/src/server/common/common-preset.js           | 2 +-
 lib/core/src/server/manager/manager-webpack.config.js | 2 +-
 lib/core/src/server/preview/iframe-webpack.config.js  | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/core/src/server/common/common-preset.js b/lib/core/src/server/common/common-preset.js
index 10b15ffe7797..8ef5e36fa30f 100644
--- a/lib/core/src/server/common/common-preset.js
+++ b/lib/core/src/server/common/common-preset.js
@@ -10,4 +10,4 @@ export const babel = async (_, options) => {
   );
 };
 
-export const logLevel = () => 'info';
+export const logLevel = (previous, options) => previous || options.loglevel || 'info';
diff --git a/lib/core/src/server/manager/manager-webpack.config.js b/lib/core/src/server/manager/manager-webpack.config.js
index 49fe2f0f8a5a..488f33b31db0 100644
--- a/lib/core/src/server/manager/manager-webpack.config.js
+++ b/lib/core/src/server/manager/manager-webpack.config.js
@@ -38,7 +38,7 @@ export default async ({
   presets,
 }) => {
   const { raw, stringified } = loadEnv();
-  const logLevel = await presets.apply('logLevel', 'info');
+  const logLevel = await presets.apply('logLevel', undefined);
   const isProd = configType === 'PRODUCTION';
   const refsTemplate = fse.readFileSync(path.join(__dirname, 'virtualModuleRef.template.js'), {
     encoding: 'utf8',
diff --git a/lib/core/src/server/preview/iframe-webpack.config.js b/lib/core/src/server/preview/iframe-webpack.config.js
index 55cc95d8accd..3453f3d1ffa6 100644
--- a/lib/core/src/server/preview/iframe-webpack.config.js
+++ b/lib/core/src/server/preview/iframe-webpack.config.js
@@ -42,7 +42,7 @@ export default async ({
   typescriptOptions,
 }) => {
   const dlls = await presets.apply('webpackDlls', []);
-  const logLevel = await presets.apply('logLevel', 'info');
+  const logLevel = await presets.apply('logLevel', undefined);
   const { raw, stringified } = loadEnv({ production: true });
   const babelLoader = createBabelLoader(babelOptions, framework);
   const isProd = configType === 'PRODUCTION';