fix(doctor): refactor doctor command

refs TryGhost#47
- split doctor checks out into separate files
- refactor doctor command to work on a "filtering" basis
- refactor usage of doctor command in other commands
- fix tests

lib/commands/doctor/checks/check-directory.js

@@ -0,0 +1,24 @@
+'use strict';
+const fs = require('fs-extra');
+const Mode = require('stat-mode');
+const path = require('path');
+const isRoot = require('path-is-root');
+
+const errors = require('../../../errors');
+
+module.exports = function checkDirectoryAndAbove(dir, extra) {
+    if (isRoot(dir)) {
+        return Promise.resolve();
+    }
+
+    return fs.lstat(dir).then((stats) => {
+        const mode = new Mode(stats);
+
+        if (!mode.others.read) {
+            return Promise.reject(new errors.SystemError(`The path ${dir} is not readable by other users on the system.
+This can cause issues with the CLI, please either make this directory readable by others or ${extra} in another location.`));
+        }
+
+        return checkDirectoryAndAbove(path.join(dir, '../'), extra);
+    });
+}

lib/commands/doctor/checks/folder-permissions.js

@@ -0,0 +1,25 @@
+'use strict';
+const fs = require('fs-extra');
+const constants = require('constants');
+
+const errors = require('../../../errors');
+const checkDirectoryAndAbove = require('./check-directory');
+
+function folderPermissions(ctx) {
+    return fs.access(process.cwd(), constants.R_OK | constants.W_OK).catch(() => {
+        return Promise.reject(new errors.SystemError(`The current directory is not writable.
+Please fix your directory permissions.`));
+    }).then(() => {
+        if (ctx.local || !ctx.system.platform.linux || (ctx.argv && ctx.argv['setup-linux-user'] === false)) {
+            return Promise.resolve();
+        }
+
+        return checkDirectoryAndAbove(process.cwd(), 'run `ghost install`');
+    });
+}
+
+module.exports = {
+    title: 'Checking current folder permissions',
+    task: folderPermissions,
+    category: ['install']
+};

lib/commands/doctor/checks/index.js

@@ -0,0 +1,14 @@
+'use strict';
+const nodeVersion = require('./node-version');
+const folderPermissions = require('./folder-permissions');
+const systemStack = require('./system-stack');
+const mysqlCheck = require('./mysql');
+const validateConfig = require('./validate-config');
+
+module.exports = [
+    nodeVersion,
+    folderPermissions,
+    systemStack,
+    mysqlCheck,
+    validateConfig
+];

lib/commands/doctor/checks/mysql.js

@@ -0,0 +1,43 @@
+'use strict';
+const execa = require('execa');
+const chalk = require('chalk');
+const includes = require('lodash/includes');
+
+const errors = require('../../../errors');
+
+function mysqlCheck(ctx) {
+    // On ubuntu, mysqld is in `/usr/sbin` but it's not automatically in the PATH of non-root users
+    // So, we modify the path env var to make things work
+    const options = ctx.system.platform.linux ? {env: {PATH: `/usr/sbin:${process.env.PATH}`}} : {};
+
+    // Technically this doesn't work on windows, but there's
+    // not an easy way to do that anyways so ¯\_(ツ)_/¯
+    return execa.shell('which mysqld', options).catch(() => {
+        ctx.ui.log(`${chalk.yellow(`Local MySQL install not found. You can ignore this if you are using a remote MySQL host.
+Alternatively you could:`)}
+${chalk.blue('a)')} install MySQL locally
+${chalk.blue('b)')} run ${chalk.cyan('`ghost install --db=sqlite3`')} to use sqlite
+${chalk.blue('c)')} run ${chalk.cyan('`ghost install local`')} to get a development install using sqlite3.`);
+
+        const confirmPromise = ctx.ui.allowPrompt ?
+            ctx.ui.confirm(chalk.blue('Continue anyway?'), false) :
+            Promise.resolve({yes: false});
+
+        return confirmPromise.then(answer => answer.yes || Promise.reject(
+            new errors.SystemError('MySQL check failed.')
+        ));
+    });
+}
+
+module.exports = {
+    title: 'Checking for a MySQL installation',
+    task: mysqlCheck,
+    // Disable this check if:
+    // a) local install OR
+    // b) --db sqlite3 is passed OR
+    // c) --dbhost is passed and IS NOT 'localhost' or '127.0.0.1'
+    enabled: (ctx) => !ctx.local &&
+        ctx.argv.db !== 'sqlite3' &&
+        (!ctx.argv.dbhost || includes(['localhost', '127.0.0.1'], ctx.argv.dbhost)),
+    category: ['install']
+};

lib/commands/doctor/checks/node-version.js

@@ -0,0 +1,28 @@
+'use strict';
+const chalk = require('chalk');
+const semver = require('semver');
+
+const errors = require('../../../errors');
+const cliPackage = require('../../../../package');
+const checkDirectoryAndAbove = require('./check-directory');
+
+function nodeVersion(ctx) {
+    if (process.env.GHOST_NODE_VERSION_CHECK !== 'false' && !semver.satisfies(process.versions.node, cliPackage.engines.node)) {
+        return Promise.reject(new errors.SystemError(`${chalk.red('The version of Node.js you are using is not supported.')}
+${chalk.gray('Supported: ')}${cliPackage.engines.node}
+${chalk.gray('Installed: ')}${process.versions.node}
+See ${chalk.underline.blue('https://docs.ghost.org/v1/docs/supported-node-versions')} for more information`));
+    }
+
+    if (ctx.local || !ctx.system.platform.linux || (ctx.argv && ctx.argv['setup-linux-user'] === false)) {
+        return Promise.resolve();
+    }
+
+    return checkDirectoryAndAbove(process.argv[0], 'install node and Ghost-CLI');
+}
+
+module.exports = {
+    title: 'Checking system Node.js version',
+    task: nodeVersion,
+    category: ['install']
+};