====Helpful Functions====

Below are a couple of //utility functions// that might be useful when developing drivers.

===Timezone Conversion===

Assuming you have a 'pytz' object called **tz** in your class that contains the timezone that is considered 'local' for your data source, you can use the following functions...

<code python>
def utcToLocal(self,dt):
        if isinstance(dt,str):
            if '.' in dt:
                dt = datetime.strptime("%Y-%m-%d %H:%M:%S.%f",pytz.utc)
            else:
                dt = datetime.strptime("%Y-%m-%d %H:%M:%S",pytz.utc)            
        
        if dt.tzinfo is None:
            dt = dt.replace(tzinfo = pytz.utc)

        if self.timezone == "utc":
            return dt        
       
        lt = dt.astimezone(self.tz)        
        return lt

    def localToUTC(self,dt):

        if isinstance(dt,str):
            if '.' in dt:
                dt = datetime.strptime("%Y-%m-%d %H:%M:%S.%f")
            else:
                dt = datetime.strptime("%Y-%m-%d %H:%M:%S")


        if dt.tzinfo is None:
            dt = self.tz.localize(dt)

        if self.timezone == "utc":
            return dt        
        
        lt = dt.astimezone(pytz.utc)
        return lt
        
  </code>
  
These two functions take the passed datetime (converting it from a string if required) and converts it between either UTC and the data-sources local time, or the data-sources local time and UTC.

===Event Cleanup===

Most Python objects can't be converted directly into JSON - this code converts each of the values in your dictionary to **strings** to make sure they can be sent to the ARDI server.

Note that it also does the job of converting Python **datetime** objects to both local and UTC versions (assuming your class has a 'tz' variable and is using the datetime functions detailed above).

<code python>
#Convert to strings whevever possible
keys = list(dct.keys())
for d in keys:
    #Convert dates
    if isinstance(dct[d],datetime.datetime):

        #Make local and UTC versions of dates. All raw dates should be UTC.
        if self.timezone != "utc":
            dct[d + "_local"] = dct[d].strftime("%Y-%m-%d %H:%M:%S")
            dct[d + "_utc"] = self.localToUTC(dct[d]).strftime("%Y-%m-%d %H:%M:%S")
            dct[d] = dct[d + "_utc"]
        else:
            dct[d] = dct[d].strftime("%Y-%m-%d %H:%M:%S")
    else:
        dct[d] = str(dct[d]) 
</code>