Fixes bug when dealing with empty JSON requests or empty appointment field

When posting a request via requests.post the json field was dumped to json, but it shouldn't have been since requests deals with this internally. That meant that the requests made by the code didn't match proper JSON.
In line with this, the API was only parsing this type POST requests correctly, making add_appointment to fail if a proper formatted JSON was passed.

On top of that, empty appointments were not checked in the Inspector before trying to get data from them, making it crash if a JSON was posted to add_appointment not containing the `appointment` field. Unit tests for this should be added.

cli/teos_cli.py

@@ -249,7 +249,7 @@ def post_appointment(data, teos_url):
     logger.info("Sending appointment to the Eye of Satoshi")
 
     try:
-        return requests.post(url=add_appointment_endpoint, json=json.dumps(data), timeout=5)
+        return requests.post(url=add_appointment_endpoint, json=data, timeout=5)
 
     except ConnectTimeout:
         logger.error("Can't connect to the Eye of Satoshi's API. Connection timeout")

teos/api.py

@@ -1,5 +1,4 @@
 import os
-import json
 import logging
 from flask import Flask, request, abort, jsonify
 
@@ -55,7 +54,7 @@ class API:
 
         if request.is_json:
             # Check content type once if properly defined
-            request_data = json.loads(request.get_json())
+            request_data = request.get_json()
             appointment = self.inspector.inspect(
                 request_data.get("appointment"), request_data.get("signature"), request_data.get("public_key")
             )

teos/inspector.py

@@ -54,6 +54,9 @@ class Inspector:
             Errors are defined in :mod:`Errors <teos.errors>`.
         """
 
+        if appointment_data is None:
+            return errors.APPOINTMENT_EMPTY_FIELD, "empty appointment received"
+
         block_height = self.block_processor.get_block_count()
 
         if block_height is not None:

test/teos/unit/test_api.py

@@ -72,7 +72,7 @@ def new_appt_data():
 
 
 def add_appointment(new_appt_data):
-    r = requests.post(url=add_appointment_endpoint, json=json.dumps(new_appt_data), timeout=5)
+    r = requests.post(url=add_appointment_endpoint, json=new_appt_data, timeout=5)
 
     if r.status_code == 200:
         appointments.append(new_appt_data["appointment"])