Add JS config API

IPython/html/static/services/config.js

@@ -0,0 +1,80
+// Copyright (c) IPython Development Team.
+// Distributed under the terms of the Modified BSD License.
+
+define([
+    'jquery',
+    'base/js/utils',
+    ],
+function($, utils) {
+    var ConfigSection = function(section_name, options) {
+        this.section_name = section_name;
+        this.base_url = options.base_url;
+        this.data = {};
+        
+        var that = this;
+        
+        /* .loaded is a promise, fulfilled the first time the config is loaded
+         * from the server. Code can do:
+         *      conf.loaded.then(function() { ... using conf.data ... });
+         */
+        this._one_load_finished = false;
+        this.loaded = new Promise(function(resolve, reject) {
+            that._finish_firstload = resolve;
+        });
+    };
+
+    ConfigSection.prototype.api_url = function() {
+        return utils.url_join_encode(this.base_url, 'api/config', that.section_name);
+    };
+    
+    ConfigSection.prototype._load_done = function() {
+        if (!this._one_load_finished) {
+            this._one_load_finished = true;
+            this._finish_firstload();
+        }
+    };
+    
+    ConfigSection.prototype.load = function() {
+        var p = new Promise(function(resolve, reject) {
+            $.ajax(this.api_url(), {
+                cache : false,
+                type : "GET",
+                dataType : "json",
+                success: function(data, status, jqXHR) {
+                    this.data = data;
+                    this._load_done();
+                    resolve(data);
+                },
+                error: function(jqXHR, status, error) {
+                    // Should never happen; mark as loaded so things don't keep
+                    // waiting.
+                    this._load_done();
+                    utils.log_ajax_error(jqXHR, status, error);
+                    reject(utils.wrap_ajax_error(jqXHR, status, error));
+                }
+            });
+        });
+    };
+    
+    ConfigSection.prototype.update = function(newdata) {
+        return new Promise(function(resolve, reject) {
+            $.ajax(this.api_url(), {
+                processData: false;
+                type : "PATCH",
+                data: JSON.stringify(newdata),
+                dataType : "json",
+                contentType: 'application/json',
+                success: function(data, status, jqXHR) {
+                    this.data = data;
+                    this._load_done();
+                    resolve(data);
+                },
+                error: function(jqXHR, status, error) {
+                    utils.log_ajax_error(jqXHR, status, error);
+                    reject(utils.wrap_ajax_error(jqXHR, status, error));
+                }
+            });
+        });
+    };
+
+});