add /api endpoint for automated flows (#316)

* add /api endpoint

* pass password in request body when using API

* flake8 fixed; tests added

* flake8 fixed test.py

---------

Co-authored-by: Reinoud van Leeuwen <reinoud.van.leeuwen@itcreation.nl>

README.rst

@@ -96,6 +96,40 @@ need to change this.
 
 ``HOST_OVERRIDE``: (optional) Used to override the base URL if the app is unaware. Useful when running behind reverse proxies like an identity-aware SSO. Example: ``sub.domain.com``
 
+API
+---
+
+SnapPass also has a simple API that can be used to create passwords links. The advantage of using the API is that
+you can create a password and retrieve the link without having to open the web interface. This is useful if you want to
+embed it in a script or use it in a CI/CD pipeline.
+
+To create a password, send a POST request to ``/api/set_password`` like so:
+
+::
+
+    $ curl -X POST -H "Content-Type: application/json"  -d '{"password": "foobar"}' http://localhost:5000/api/set_password/
+
+This will return a JSON response with the password link:
+
+::
+
+    {
+        "link": "http://127.0.0.1:5000/snappassbedf19b161794fd288faec3eba15fa41~hHnILpQ50ZfJc3nurDfHCb_22rBr5gGEya68e_cZOrY%3D",
+        "ttl":1209600
+    }
+
+the default TTL is 2 weeks (1209600 seconds), but you can override it by adding a expiration parameter:
+
+::
+
+    $ curl -X POST -H "Content-Type: application/json"  -d '{"password": "foobar", "ttl": 3600 }' http://localhost:5000/api/set_password/
+
+Notes:
+
+- When using the API, you can specify any ttl, as long as it is lower than the default.
+- The password is passed in the body of the request rather than in the URL. This is to prevent the password from being logged in the server logs.
+- Depending on the environment you are running it, you might want to expose the ``/api`` endpoint to your internal network only, and put the web interface behind authentication.
+
 Docker
 ------
 

snappass/main.py

@@ -17,7 +17,6 @@ URL_PREFIX = os.environ.get('URL_PREFIX', None)
 HOST_OVERRIDE = os.environ.get('HOST_OVERRIDE', None)
 TOKEN_SEPARATOR = '~'
 
-
 # Initialize Flask Application
 app = Flask(__name__)
 if os.environ.get('DEBUG'):
@@ -37,6 +36,7 @@ babel = Babel(app, locale_selector=get_locale)
 # Initialize Redis
 if os.environ.get('MOCK_REDIS'):
     from fakeredis import FakeStrictRedis
+
     redis_client = FakeStrictRedis()
 elif os.environ.get('REDIS_URL'):
     redis_client = redis.StrictRedis.from_url(os.environ.get('REDIS_URL'))
@@ -48,7 +48,10 @@ else:
         host=redis_host, port=redis_port, db=redis_db)
 REDIS_PREFIX = os.environ.get('REDIS_PREFIX', 'snappass')
 
-TIME_CONVERSION = {'two weeks': 1209600, 'week': 604800, 'day': 86400, 'hour': 3600}
+TIME_CONVERSION = {'two weeks': 1209600, 'week': 604800, 'day': 86400,
+                   'hour': 3600}
+DEFAULT_API_TTL = 1209600
+MAX_TTL = DEFAULT_API_TTL
 
 
 def check_redis_alive(fn):
@@ -63,6 +66,7 @@ def check_redis_alive(fn):
                 sys.exit(0)
             else:
                 return abort(500)
+
     return inner
 
 
@@ -163,6 +167,22 @@ def clean_input():
     return TIME_CONVERSION[time_period], request.form['password']
 
 
+def set_base_url(req):
+    if NO_SSL:
+        if HOST_OVERRIDE:
+            base_url = f'http://{HOST_OVERRIDE}/'
+        else:
+            base_url = req.url_root
+    else:
+        if HOST_OVERRIDE:
+            base_url = f'https://{HOST_OVERRIDE}/'
+        else:
+            base_url = req.url_root.replace("http://", "https://")
+    if URL_PREFIX:
+        base_url = base_url + URL_PREFIX.strip("/") + "/"
+    return base_url
+
+
 @app.route('/', methods=['GET'])
 def index():
     return render_template('set_password.html')
@@ -170,26 +190,33 @@ def index():
 
 @app.route('/', methods=['POST'])
 def handle_password():
-    ttl, password = clean_input()
-    token = set_password(password, ttl)
-
-    if NO_SSL:
-        if HOST_OVERRIDE:
-            base_url = f'http://{HOST_OVERRIDE}/'
+    password = request.form.get('password')
+    ttl = request.form.get('ttl')
+    if clean_input():
+        ttl = TIME_CONVERSION[ttl.lower()]
+        token = set_password(password, ttl)
+        base_url = set_base_url(request)
+        link = base_url + quote_plus(token)
+        if request.accept_mimetypes.accept_json and not \
+           request.accept_mimetypes.accept_html:
+            return jsonify(link=link, ttl=ttl)
         else:
-            base_url = request.url_root
+            return render_template('confirm.html', password_link=link)
     else:
-        if HOST_OVERRIDE:
-            base_url = f'https://{HOST_OVERRIDE}/'
-        else:
-            base_url = request.url_root.replace("http://", "https://")
-    if URL_PREFIX:
-        base_url = base_url + URL_PREFIX.strip("/") + "/"
-    link = base_url + quote_plus(token)
-    if request.accept_mimetypes.accept_json and not request.accept_mimetypes.accept_html:
+        abort(500)
+
+
+@app.route('/api/set_password/', methods=['POST'])
+def api_handle_password():
+    password = request.json.get('password')
+    ttl = int(request.json.get('ttl', DEFAULT_API_TTL))
+    if password and isinstance(ttl, int) and ttl <= MAX_TTL:
+        token = set_password(password, ttl)
+        base_url = set_base_url(request)
+        link = base_url + quote_plus(token)
         return jsonify(link=link, ttl=ttl)
     else:
-        return render_template('confirm.html', password_link=link)
+        abort(500)
 
 
 @app.route('/<password_key>', methods=['GET'])

tests.py

@@ -163,6 +163,44 @@ class SnapPassRoutesTestCase(TestCase):
             frozen_time.move_to("2020-05-22 12:00:00")
             self.assertIsNone(snappass.get_password(key))
 
+    def test_set_password_api(self):
+        with freeze_time("2020-05-08 12:00:00") as frozen_time:
+            password = 'my name is my passport. verify me.'
+            rv = self.app.post(
+                '/api/set_password/',
+                headers={'Accept': 'application/json'},
+                json={'password': password, 'ttl': '1209600'},
+            )
+
+            json_content = rv.get_json()
+            key = re.search(r'https://localhost/([^"]+)', json_content['link']).group(1)
+            key = unquote(key)
+
+            frozen_time.move_to("2020-05-22 11:59:59")
+            self.assertEqual(snappass.get_password(key), password)
+
+            frozen_time.move_to("2020-05-22 12:00:00")
+            self.assertIsNone(snappass.get_password(key))
+
+    def test_set_password_api_default_ttl(self):
+        with freeze_time("2020-05-08 12:00:00") as frozen_time:
+            password = 'my name is my passport. verify me.'
+            rv = self.app.post(
+                '/api/set_password/',
+                headers={'Accept': 'application/json'},
+                json={'password': password},
+            )
+
+            json_content = rv.get_json()
+            key = re.search(r'https://localhost/([^"]+)', json_content['link']).group(1)
+            key = unquote(key)
+
+            frozen_time.move_to("2020-05-22 11:59:59")
+            self.assertEqual(snappass.get_password(key), password)
+
+            frozen_time.move_to("2020-05-22 12:00:00")
+            self.assertIsNone(snappass.get_password(key))
+
 
 if __name__ == '__main__':
     unittest.main()