MXS-1300: Add initial implementation of MaxCtrl

This is the administrative client that uses the REST API to communicate
with MaxScale. It is written in Node.js as it can handle the JSON format
data returned by the REST API natively. Currently only list and show
functionality is implemented.

client/maxctrl/common.js

@@ -0,0 +1,155 @@
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
+ *
+ * Change Date: 2020-01-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+var _ = require('lodash-getpath')
+var request = require('request');
+var colors = require('colors/safe');
+var Table = require('cli-table');
+var assert = require('assert')
+
+module.exports = function() {
+    const maxctrl_version = '1.0.0';
+
+    // Common options for all commands
+    this.program = require('yargs');
+    this.program
+        .group(['u', 'p', 'h', 'p', 'P', 's'], 'Global Options:')
+        .option('u', {
+            alias:'user',
+            global: true,
+            default: 'mariadb',
+            describe: 'Username to use',
+            type: 'string'
+        })
+        .option('p', {
+            alias: 'password',
+            describe: 'Password for the user',
+            default: 'admin',
+            type: 'string'
+        })
+        .option('h', {
+            alias: 'host',
+            describe: 'The hostname or address where MaxScale is located',
+            default: 'localhost',
+            type: 'string'
+        })
+        .option('P', {
+            alias: 'port',
+            describe: 'The port where MaxScale REST API listens on',
+            default: 8989,
+            type: 'number'
+        })
+        .option('s', {
+            alias: 'secure',
+            describe: 'Enable TLS encryption of connections',
+            default: 'false',
+            type: 'boolean'
+        })
+        .version(maxctrl_version)
+        .help()
+
+    // Request a resource collection and format it as a table
+    this.getCollection = function (resource, headers, parts) {
+
+        doRequest(resource, function(res) {
+            var table = getTable(headers)
+
+            res.data.forEach(function(i) {
+                row = []
+
+                parts.forEach(function(p) {
+                    var v = _.getPath(i, p, "")
+
+                    if (Array.isArray(v)) {
+                        v = v.join(", ")
+                    }
+                    row.push(v)
+                })
+
+                table.push(row)
+            })
+
+            console.log(table.toString())
+        })
+    }
+
+    // Request a single resource and format it as a key-value list
+    this.getResource = function (resource, fields) {
+
+        doRequest(resource, function(res) {
+            var table = new Table()
+
+            fields.forEach(function(i) {
+                var k = Object.keys(i)[0]
+                var path = i[k]
+                var v = _.getPath(res.data, path, "")
+
+                if (Array.isArray(v) && typeof(v[0]) != 'object') {
+                    v = v.join(", ")
+                } else if (typeof(v) == 'object') {
+                    v = JSON.stringify(v, null, 4)
+                }
+
+                var o = {}
+                o[k] = v
+                table.push(o)
+            })
+
+            console.log(table.toString())
+        })
+    }
+
+    // Helper for converting endpoints to acutal URLs
+    this.getUri = function(endpoint, options) {
+        var base = 'http://';
+        var argv = this.program.argv
+
+        if (argv.secure) {
+            base = 'https://';
+        }
+
+        return base + argv.user + ':' + argv.password + '@' +
+            argv.host + ':' + argv.port + '/v1/' + endpoint;
+    }
+
+    // Helper for executing requests and handling their responses
+    this.doRequest = function(resource, cb) {
+        request({
+            uri: getUri(resource),
+            json: true
+        }, function(err, resp, res) {
+            if (resp.statusCode == 200) {
+                cb(res)
+            } else if (resp.statusCode == 204) {
+                console.log(colors.green("OK"))
+            } else {
+                console.log("Error:", resp.statusCode, resp.statusMessage)
+                if (res) {
+                    console.log(res)
+                }
+            }
+        })
+    }
+}
+
+// Creates a table-like array for output. The parameter is an array of header names
+function getTable(headobj) {
+
+    for (i = 0; i < headobj.length; i++) {
+        headobj[i] = colors.cyan(headobj[i])
+    }
+
+    return new Table({
+        head: headobj
+    })
+}