feat: handle 2-legged OAuth2 authentication method

Signed-off-by: Adrien Barreau <adrien.barreau@ovhcloud.com>

README.rst

@@ -1,5 +1,5 @@
 .. image:: https://github.com/ovh/python-ovh/raw/master/docs/img/logo.png
-           :alt: Python & OVH APIs
+           :alt: Python & OVHcloud APIs
            :target: https://pypi.python.org/pypi/ovh
 
 Lightweight wrapper around OVHcloud's APIs. Handles all the hard work including
@@ -73,9 +73,9 @@ To interact with the APIs, the SDK needs to identify itself using an
 ``application_key`` and an ``application_secret``. To get them, you need
 to register your application. Depending the API you plan to use, visit:
 
-- `OVH Europe <https://eu.api.ovh.com/createApp/>`_
-- `OVH US <https://api.us.ovhcloud.com/createApp/>`_
-- `OVH North-America <https://ca.api.ovh.com/createApp/>`_
+- `OVHcloud Europe <https://eu.api.ovh.com/createApp/>`_
+- `OVHcloud US <https://api.us.ovhcloud.com/createApp/>`_
+- `OVHcloud North-America <https://ca.api.ovh.com/createApp/>`_
 - `So you Start Europe <https://eu.api.soyoustart.com/createApp/>`_
 - `So you Start North America <https://ca.api.soyoustart.com/createApp/>`_
 - `Kimsufi Europe <https://eu.api.kimsufi.com/createApp/>`_
@@ -104,12 +104,15 @@ it looks like:
     ; uncomment following line when writing a script application
     ; with a single consumer key.
     ;consumer_key=my_consumer_key
+    ; uncomment to enable oauth2 authentication
+    ;client_id=my_client_id
+    ;client_secret=my_client_secret
 
 Depending on the API you want to use, you may set the ``endpoint`` to:
 
-* ``ovh-eu`` for OVH Europe API
-* ``ovh-us`` for OVH US API
-* ``ovh-ca`` for OVH North-America API
+* ``ovh-eu`` for OVHcloud Europe API
+* ``ovh-us`` for OVHcloud US API
+* ``ovh-ca`` for OVHcloud North-America API
 * ``soyoustart-eu`` for So you Start Europe API
 * ``soyoustart-ca`` for So you Start North America API
 * ``kimsufi-eu`` for Kimsufi Europe API
@@ -120,8 +123,21 @@ See Configuration_ for more information on available configuration mechanisms.
 .. note:: When using a versioning system, make sure to add ``ovh.conf`` to ignored
           files. It contains confidential/security-sensitive information!
 
-3. Authorize your application to access a customer account
-**********************************************************
+3. Authorize your application to access a customer account using OAuth2
+***********************************************************************
+
+``python-ovh`` supports two forms of authentication:
+* OAuth2, using scopped service accounts, and compatible with OVHcloud IAM
+* application key & application secret & consumer key (covered in the next chapter)
+
+For OAuth2, first, you need to generate a pair of valid ``client_id`` and ``client_secret``: you
+can proceed by [following this documentation](https://help.ovhcloud.com/csm/en-manage-service-account?id=kb_article_view&sysparm_article=KB0059343)
+
+Once you have retrieved your ``client_id`` and ``client_secret``, you can create and edit
+a configuration file that will be used by ``python-ovh``.
+
+4. Authorize your application to access a customer account using custom OVHcloud authentication
+***********************************************************************************************
 
 To allow your application to access a customer account using the API on your
 behalf, you need a **consumer key (CK)**.
@@ -164,7 +180,7 @@ Install a new mail redirection
 ------------------------------
 
 e-mail redirections may be freely configured on domains and DNS zones hosted by
-OVH to an arbitrary destination e-mail using API call
+OVHcloud to an arbitrary destination e-mail using API call
 ``POST /email/domain/{domain}/redirection``.
 
 For this call, the api specifies that the source address shall be given under the
@@ -195,7 +211,7 @@ is only supported with reserved keywords.
 Grab bill list
 --------------
 
-Let's say you want to integrate OVH bills into your own billing system, you
+Let's say you want to integrate OVHcloud bills into your own billing system, you
 could just script around the ``/me/bills`` endpoints and even get the details
 of each bill lines using ``/me/bill/{billId}/details/{billDetailId}``.
 
@@ -359,7 +375,7 @@ You have 3 ways to provide configuration to the client:
 Embed the configuration in the code
 -----------------------------------
 
-The straightforward way to use OVH's API keys is to embed them directly in the
+The straightforward way to use OVHcloud's API keys is to embed them directly in the
 application code. While this is very convenient, it lacks of elegance and
 flexibility.
 
@@ -547,25 +563,25 @@ build HTML documentation:
 Supported APIs
 ==============
 
-OVH Europe
-----------
+OVHcloud Europe
+---------------
 
 - **Documentation**: https://eu.api.ovh.com/
 - **Community support**: api-subscribe@ml.ovh.net
 - **Console**: https://eu.api.ovh.com/console
 - **Create application credentials**: https://eu.api.ovh.com/createApp/
 - **Create script credentials** (all keys at once): https://eu.api.ovh.com/createToken/
 
-OVH US
-----------
+OVHcloud US
+-----------
 
 - **Documentation**: https://api.us.ovhcloud.com/
 - **Console**: https://api.us.ovhcloud.com/console/
 - **Create application credentials**: https://api.us.ovhcloud.com/createApp/
 - **Create script credentials** (all keys at once): https://api.us.ovhcloud.com/createToken/
 
-OVH North America
------------------
+OVHcloud North America
+---------------------
 
 - **Documentation**: https://ca.api.ovh.com/
 - **Community support**: api-subscribe@ml.ovh.net

ovh/client.py

@@ -49,6 +49,7 @@
     BadParametersError,
     Forbidden,
     HTTPError,
+    InvalidConfiguration,
     InvalidCredential,
     InvalidKey,
     InvalidRegion,
@@ -60,8 +61,9 @@
     ResourceExpiredError,
     ResourceNotFoundError,
 )
+from .oauth2 import OAuth2
 
-#: Mapping between OVH API region names and corresponding endpoints
+# Mapping between OVH API region names and corresponding endpoints
 ENDPOINTS = {
     "ovh-eu": "https://eu.api.ovh.com/1.0",
     "ovh-us": "https://api.us.ovhcloud.com/1.0",
@@ -72,9 +74,16 @@
     "soyoustart-ca": "https://ca.api.soyoustart.com/1.0",
 }
 
-#: Default timeout for each request. 180 seconds connect, 180 seconds read.
+# Default timeout for each request. 180 seconds connect, 180 seconds read.
 TIMEOUT = 180
 
+# OAuth2 token provider URLs
+OAUTH2_TOKEN_URLS = {
+    "ovh-eu": "https://www.ovh.com/auth/oauth2/token",
+    "ovh-ca": "https://ca.ovh.com/auth/oauth2/token",
+    "ovh-us": "https://us.ovhcloud.com/auth/oauth2/token",
+}
+
 
 class Client:
     """
@@ -116,18 +125,24 @@ def __init__(
         consumer_key=None,
         timeout=TIMEOUT,
         config_file=None,
+        client_id=None,
+        client_secret=None,
     ):
         """
         Creates a new Client. No credential check is done at this point.
 
-        The ``application_key`` identifies your application while
-        ``application_secret`` authenticates it. On the other hand, the
-        ``consumer_key`` uniquely identifies your application's end user without
-        requiring his personal password.
+        When using OAuth2 authentication, ``client_id`` and ``client_secret``
+        will be used to initiate a Client Credential OAuth2 flow.
+
+        When using the OVHcloud authentication method, the ``application_key``
+        identifies your application while ``application_secret`` authenticates
+        it. On the other hand, the ``consumer_key`` uniquely identifies your
+        application's end user without requiring his personal password.
 
-        If any of ``endpoint``, ``application_key``, ``application_secret``
-        or ``consumer_key`` is not provided, this client will attempt to locate
-        from them from environment, ~/.ovh.cfg or /etc/ovh.cfg.
+        If any of ``endpoint``, ``application_key``, ``application_secret``,
+        ``consumer_key``, ``client_id`` or ``client_secret`` is not provided,
+        this client will attempt to locate from them from environment,
+        ``~/.ovh.cfg`` or ``/etc/ovh.cfg``.
 
         See :py:mod:`ovh.config` for more information on supported
         configuration mechanisms.
@@ -139,9 +154,11 @@ def __init__(
         180 seconds for connection and 180 seconds for read.
 
         :param str endpoint: API endpoint to use. Valid values in ``ENDPOINTS``
-        :param str application_key: Application key as provided by OVH
-        :param str application_secret: Application secret key as provided by OVH
+        :param str application_key: Application key as provided by OVHcloud
+        :param str application_secret: Application secret key as provided by OVHcloud
         :param str consumer_key: uniquely identifies
+        :param str client_id: OAuth2 client ID
+        :param str client_secret: OAuth2 client secret
         :param tuple timeout: Connection and read timeout for each request
         :param float timeout: Same timeout for both connection and read
         :raises InvalidRegion: if ``endpoint`` can't be found in ``ENDPOINTS``.
@@ -175,6 +192,50 @@ def __init__(
             consumer_key = configuration.get(endpoint, "consumer_key")
         self._consumer_key = consumer_key
 
+        # load OAuth2 data
+        if client_id is None:
+            client_id = configuration.get(endpoint, "client_id")
+        self._client_id = client_id
+
+        if client_secret is None:
+            client_secret = configuration.get(endpoint, "client_secret")
+        self._client_secret = client_secret
+
+        # configuration validation
+        if bool(self._client_id) is not bool(self._client_secret):
+            raise InvalidConfiguration("Invalid OAuth2 config, both client_id and client_secret must be given")
+
+        if bool(self._application_key) is not bool(self._application_secret):
+            raise InvalidConfiguration(
+                "Invalid authentication config, both application_key and application_secret must be given"
+            )
+
+        if self._client_id is not None and self._application_key is not None:
+            raise InvalidConfiguration(
+                "Can't use both application_key/application_secret and OAuth2 client_id/client_secret"
+            )
+        if self._client_id is None and self._application_key is None:
+            raise InvalidConfiguration(
+                "Missing authentication information, you need to provide at least an application_key/application_secret"
+                " or a client_id/client_secret"
+            )
+        if self._client_id and endpoint not in OAUTH2_TOKEN_URLS:
+            raise InvalidConfiguration(
+                "OAuth2 authentication is not compatible with endpoint "
+                + endpoint
+                + " (it can only be used with ovh-eu, ovh-ca and ovh-us)"
+            )
+
+        # when in OAuth2 mode, instantiate the oauthlib client
+        if self._client_id:
+            self._oauth2 = OAuth2(
+                client_id=self._client_id,
+                client_secret=self._client_secret,
+                token_url=OAUTH2_TOKEN_URLS[endpoint],
+            )
+        else:
+            self._oauth2 = None
+
         # lazy load time delta
         self._time_delta = None
 
@@ -524,7 +585,6 @@ def raw_call(self, method, path, data=None, need_auth=True, headers=None):
 
         if headers is None:
             headers = {}
-        headers["X-Ovh-Application"] = self._application_key
 
         # include payload
         if data is not None:
@@ -533,6 +593,9 @@ def raw_call(self, method, path, data=None, need_auth=True, headers=None):
 
         # sign request. Never sign 'time' or will recurse infinitely
         if need_auth:
+            if self._oauth2:
+                return self._oauth2.session.request(method, target, headers=headers, data=body, timeout=self._timeout)
+
             if not self._application_secret:
                 raise InvalidKey("Invalid ApplicationSecret '%s'" % self._application_secret)
 
@@ -551,4 +614,5 @@ def raw_call(self, method, path, data=None, need_auth=True, headers=None):
             headers["X-Ovh-Timestamp"] = now
             headers["X-Ovh-Signature"] = "$1$" + signature.hexdigest()
 
+        headers["X-Ovh-Application"] = self._application_key
         return self._session.request(method, target, headers=headers, data=body, timeout=self._timeout)

ovh/config.py

@@ -49,6 +49,8 @@
     application_key=my_app_key
     application_secret=my_application_secret
     consumer_key=my_consumer_key
+    client_id=my_client_id
+    client_secret=my_client_secret
 
 The client will successively attempt to locate this configuration file in
 

ovh/exceptions.py

@@ -59,6 +59,10 @@ class InvalidCredential(APIError):
     """Raised when trying to sign request with invalid consumer key"""
 
 
+class InvalidConfiguration(APIError):
+    """Raised when trying to load an invalid configuration into a client"""
+
+
 class InvalidResponse(APIError):
     """Raised when api response is not valid json"""
 
@@ -101,3 +105,7 @@ class Forbidden(APIError):
 
 class ResourceExpiredError(APIError):
     """Raised when requested resource expired."""
+
+
+class OAuth2FailureError(APIError):
+    """Raised when the OAuth2 workflow fails"""