HTTPError: Bad response when making requests in loop

[JoBerkner]

I am getting a

HTTPError: Bad response

I was so free to actually get the correct error code. It is a 400 bad request code.

It seems it only happens when I use a loop through my pandas dataframe instances because when I run my code for a single instance I am getting the correct values as well as when I am using a direct URL request in my browser.

Here is my function which is called later (with df being the dataframe)

def engineer_features(df):
    from datetime import datetime as dt
    from darksky import forecast

    print("Add weather data...")
    
    # Add Windspeed
    df['ISSTORM'] = 0
    
    # Add Temperature
    df['ISHOT'] = 0
    df['ISCOLD'] = 0
    
    # Add Precipitation probability 
    #    (because the weather station is not at the coordinate of the taxi 
    #    only a probability is added, but in regard to the center of Porto 
    #    (because else the API calls would have been costly))
    df['PRECIPPROB'] = 0
    
    # sort data frame
    data_times = df.sort_values(by='TIMESTAMP')
    
    # initialize variable for previous day's date day (day before the first day)
    prevDay = data_times.at[0,'TIMESTAMP'].date().day - 1
    
    #initialize hour counter
    hourCount = 0
    
    # add personal DarkSky API key and asssign with location data
    key = 'MYKEY'
    PORTO = key, 41.1579, -8.6291
    
    # loop through the sorted dataframe and add weather related data to the main dataframe
    for index, row in data_times.iterrows():
        
        # if the new row is a new day make a new API call for weather data of that new day
        if row["TIMESTAMP"].day != prevDay:
            
            # get Weather data
            t = row["TIMESTAMP"].date().isoformat()
            porto = forecast(*PORTO, time=t)
            porto.refresh(units='si')
           
        ###...more code

[lukaskubis]

How many of these requests are you making? Keep in mind that your API key will allow you to do max 1000 requests per day.