adding a link generator binder

README.md

@@ -1,5 +1,7 @@
 # nbgitpuller
 
+[![Binder](https://mybinder.org/badge.svg)](https://mybinder.org/v2/gh/data-8/nbgitpuller/master?urlpath=apps/binder%2Flink_generator.ipynb)
+
 One-way synchronization of a remote git repository to a local git repository,
 with automatic conflict resolution.
 
@@ -61,6 +63,9 @@ You should *not* use this when:
 
 # Constructing the nbgitpuller URL
 
+Launch this Binder for an interactive link generator
+[![Binder](https://mybinder.org/badge.svg)](https://mybinder.org/v2/gh/data-8/nbgitpuller/master?urlpath=apps/binder%2Flink_generator.ipynb)
+
 You can construct a working nbgitpuller URL like this:
 
 ```

binder/link_generator.ipynb

@@ -0,0 +1,62 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Generate `nbgitpuller` links for your JupyterHub\n",
+    "\n",
+    "Below is an interactive widget that lets you compose interact links\n",
+    "with `nbgitpuller`. In the form below, input your JupyterHub\n",
+    "URL as well as the repository\n",
+    "URL and information for the content you wish to share, and your interact\n",
+    "link will be printed below."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from ipywidgets import interact\n",
+    "\n",
+    "@interact\n",
+    "def make_nbgitpuller_link(hub_url='', repo_url='', branch='', subPath='', app=''):\n",
+    "    \"\"\"Generate an ipywidget form that creates an interact link.\"\"\"\n",
+    "    hub_url = hub_url.strip()\n",
+    "    kwargs = {}\n",
+    "    for name, val in [('repo', repo_url), ('branch', branch), ('subPath', subPath), ('app', app)]:\n",
+    "        if len(val) > 1:\n",
+    "            kwargs[name] = val.strip()\n",
+    "    params = f'&'.join(['{}={}'.format(nm, val) for nm, val in kwargs.items()])\n",
+    "    url = f'{hub_url}/hub/user-redirect/git-pull?{params}'\n",
+    "    if len(app) > 0 and app.strip() not in ['notebook', 'lab']:\n",
+    "        print('app must be one of [\"notebook\", \"lab\"]')\n",
+    "    elif (len(hub_url) > 0) and (len(repo_url) > 0):\n",
+    "        print(url)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.6.5"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}

binder/postBuild

@@ -0,0 +1,3 @@
+#!/bin/bash
+jupyter nbextension     enable --py --sys-prefix appmode
+jupyter serverextension enable --py --sys-prefix appmode

binder/requirements.txt

@@ -0,0 +1,2 @@
+ipywidgets
+appmode