Merge pull request #1 from ravigadila/converter

Converter

Author: Ravi kumar

.gitignore

@@ -5,7 +5,7 @@ __pycache__/
 
 # C extensions
 *.so
-
+*.*~
 # Distribution / packaging
 .Python
 env/
@@ -60,3 +60,4 @@ target/
 
 #Ipython Notebook
 .ipynb_checkpoints
+env

forex-python/__init__.py

@@ -0,0 +1,74 @@
+import requests
+import datetime
+
+
+class RateNotFoundError(Exception):
+    """
+    Custom exception when conversion rate not found for given Country
+    """
+    pass
+
+
+class RatesNotAvailableError(Exception):
+    """
+    Custome Exception when http://fixer.io/ is Down are not available for currency rates
+    """
+    pass
+
+
+class Common:
+
+    def __init__(self):
+        pass
+
+    def _source_url(self):
+        return "http://api.fixer.io/"
+
+    def _get_date_string(self, date_str):
+        if date_str is None:
+            return 'latest'
+        try:
+            datetime.datetime.strptime(date_str, '%Y-%m-%d')
+            return date_str
+        except ValueError:
+            raise ValueError("Incorrect date String, date_str should be YYYY-MM-DD")
+
+
+class CurrencyRates(Common):
+
+    def get_rates(self, base_cur, date_str=None):
+        date_str = self._get_date_string(date_str)
+        payload = {'base': base_cur}
+        source_url = self._source_url() + date_str
+        response = requests.get(source_url, params=payload)
+        if response.status_code == 200:
+            rates = response.json().get('rates', {})
+            return rates
+        raise RatesNotAvailableError("Currency Rates Source Not Ready")
+
+    def get_rate(self, base_cur, dest_cur, date_str=None):
+        date_str = self._get_date_string(date_str)
+        payload = {'base': base_cur, 'symbols': dest_cur}
+        source_url = self._source_url() + date_str
+        response = requests.get(source_url, params=payload)
+        if response.status_code == 200:
+            rate = response.json().get('rates', {}).get(dest_cur)
+            if not rate:
+                raise RatesNotAvailableError("Currency Rate {0} => {1} not available for Date {2}".format(
+                    base_cur, dest_cur, date_str))
+            return rate
+        raise RatesNotAvailableError("Currency Rates Source Not Ready")
+
+    def convert(self, base_cur, dest_cur, amount, date_str=None):
+        date_str = self._get_date_string(date_str)
+        payload = {'base': base_cur, 'symbols': dest_cur}
+        source_url = self._source_url() + date_str
+        response = requests.get(source_url, params=payload)
+        if response.status_code == 200:
+            rate = response.json().get('rates', {}).get(dest_cur, None)
+            if not rate:
+                raise RatesNotAvailableError("Currency {0} => {1} rate not available for Date {2}.".format(
+                    source_url, dest_cur, date_str))
+            converted_amount = rate * amount
+            return converted_amount
+        raise RatesNotAvailableError("Currency Rates Source Not Ready")