POST-Authentication.md

+This `POST`&`GET` request will authenticate you with the Wilma
+
+***
+
+_Basepath_ for logging in: `https://<your_wilma_server>/login`
+
+_Basepath_ for obtaining the Session ID: `https://<your_wilma_server>/index_json`
+
+
+***
+
+### Obtaining the Session ID
+You can obtain the Session ID by requesting an `GET` request to the:
+> _Basepath_ for obtaining the Session ID
+
+You'll get this as a **successful response**:
+
+    {
+      "LoginResult": "Failed",
+      "SessionID": "<the_session_id>",
+      "ApiVersion": 10,
+      "Workers": []
+    }
+
+And if it manages to fail, here's an example `error response`:
+
+    {
+      "error": {
+        "id": "example-1",
+        "message": "Some weird error",
+        "description": "Don't worry, this is an example ;-)",
+        "whatnext": "",
+        "statuscode": 403
+      }
+    }
+
+Take down the `SessionID` from the successful response, and we can continue to the login
+
+***
+
+### Login request
+In order to login, you should to a `POST` request to the:
+
+> _Basepath_ for logging in: `https://<your_wilma_server>/login`
+
+These are the `POST` parameters:
+* `Login` - Username
+* `SESSIONID` - The SessionID we got in the previous response
+* `CompleteJson` - Value: `` (leave it empty) This is not a required parameter, basically it will get every page from Wilma server as json (don't confuse it with the JSON response, it just sets a `Content-Type` header to `application/json`. Althrough on some pages it will give you JSON response)
+* `ApiKey` - Generate a SHA1 key using this example: (`<Login>|<SessionID>|<API_KEY>`). `<Login>` is the username, `<SessionID>` you are familiar with, now `<API_KEY>` is a weird one. You can't get it easily. Only ways is to send a request to Visma (if no one answers, write directly to the CEO and magic will happen), or (little bit illegal) go and extract it from their app
+* `Password` - The password of user
+* `format` - Use value `json` so you will get all error messages in this request as JSON response
+
+Done with parameters, finally send it.
+If the authentication went successfully, you'll get the homepage of the user:
+
+    {
+      "LoginResult": "Ok",
+      "WilmaId": "888f7a471f187aedd6a258c4b67e2154s5741ds1",
+      "ApiVersion": 10,
+      "FormKey": "student:87654:1f8ef7cc65954655a34a2312145",
+      "ConnectIds": [],
+      "Name": "Developer From Jokela",
+      "Type": 2,
+      "PrimusId": 87654,
+      "School": "Example school",
+      "Exams": [],
+      "Observations": [],
+      "News": [],
+      "Groups": [],
+      "Photo": "",
+      "EarlyEduUser": false,
+      "Roles": []
+    }
+**One last note: **Remember to save the `Wilma2SID` cookie, it's your session cookie, it lasts about 25 minutes if not used
+
+And you get this error response if something went wrong:
+
+    {
+      "LoginResult": "Failed",
+      "SessionID": "<the_session_id>",
+      "ApiVersion": 10,
+      "Workers": []
+    }
+
+Now you're done to do more requests.
+All other requests get this kind of error response:
+
+
+    {
+      "error": {
+        "id": "example-1",
+        "message": "Some weird error",
+        "description": "Don't worry, this is an example ;-)",
+        "whatnext": "",
+        "statuscode": 403
+      }
+    }