Add support for protocol-relative request paths

Nuclos generates protocol-relative HATEOEAS links since version 4.32.
Note that we currently only support the HTTP protocol, so that gets
added to any protocol-relative path.

Author: saierd

README.md

@@ -6,7 +6,8 @@ A Python library for the REST API of [Nuclos](http://www.nuclos.de/).
 
 | Version                                                         | Compatible Nuclos versions | Download |
 | --------------------------------------------------------------- | -------------------------- | -------- |
-| [1.7](https://github.com/saierd/python-nuclos/releases/tag/1.7) | ≥ 4.7.2<br>(tested up to 4.30 as of writing)| [zip](https://github.com/saierd/python-nuclos/releases/download/1.7/python-nuclos-1.7.zip) |
+| [1.8](https://github.com/saierd/python-nuclos/releases/tag/1.8) | ≥ 4.7.2<br>(tested up to 4.44 as of writing)| [zip](https://github.com/saierd/python-nuclos/releases/download/1.8/python-nuclos-1.8.zip) |
+| [1.7](https://github.com/saierd/python-nuclos/releases/tag/1.7) | 4.7.2 - 4.31               | [zip](https://github.com/saierd/python-nuclos/releases/download/1.7/python-nuclos-1.7.zip) |
 | [1.4](https://github.com/saierd/python-nuclos/releases/tag/1.4) | 4.5.*                      | [zip](https://github.com/saierd/python-nuclos/releases/download/1.4/python-nuclos-1.4.zip) |
 | [1.0](https://github.com/saierd/python-nuclos/releases/tag/1.0) | 4.4.0                      | [zip](https://github.com/saierd/python-nuclos/releases/download/1.0/python-nuclos-1.0.zip) |
 

nuclos.py

@@ -37,6 +37,8 @@
 STATE_CHANGE_ROUTE = "boStateChanges/{}/{}/{}"
 DOCUMENT_ROUTE = "boDocuments/{}/{}/documents/{}"
 
+HTTP_PROTOCOL = "http"
+
 
 class NuclosSettings:
     def __init__(self, filename):
@@ -334,7 +336,9 @@ def request(self, path, parameters=None, data=None, method=None, auto_login=True
             self.login()
 
         url = path
-        if not url.startswith("http"):
+        if url.startswith("//"):
+            url = HTTP_PROTOCOL + ":" + url
+        if not url.startswith(HTTP_PROTOCOL):
             url = self._build_url(path, parameters)
         request = urllib.request.Request(url)
         if json_answer:
@@ -408,7 +412,7 @@ def quote(s):
         if not path.startswith("/"):
             path = "/" + path
 
-        url = "http://{}:{}/{}/rest{}".format(quote(self.settings.ip), self.settings.port,
+        url = "{}://{}:{}/{}/rest{}".format(HTTP_PROTOCOL, quote(self.settings.ip), self.settings.port,
                                               quote(self.settings.instance), quote(path))
         if param:
             url += "?" + param