Download_and_save_data.jl

function get_price_data_single(currency::String)
    
    df_out_price  = DataFrame()
    df_out_vol    = DataFrame()
    df_out_candle = DataFrame()
    date = Dates.today()

    main_dir = pwd()   
    cd("data")

    # Look for present day's CSV file, if not found, download and save data to a new file
    if isfile("$(currency)_EUR_data_$(date).csv")
        @info "Reading $(currency) data from CSV file on disk"
        global raw_df = CSV.File("$(currency)_EUR_data_$(date).csv") |> DataFrame        
    else
        try 
            @info "Fetching $(currency) data from Alpha Vantage"  
            raw = AlphaVantage.digital_currency_daily(currency, "EUR", datatype="csv") 
            global raw_df = raw_to_df(raw) 
            s2 = "$(currency)_EUR_data_$(date).csv"                   
            CSV.write(s2, raw_df)           
        catch
            println("Could not fetch data, try again later!")
            cd(main_dir)
        end         
    end  
    
    cd(main_dir)
    average_price_df(currency, raw_df, df_out_price, df_out_candle)
    vol_df(currency, raw_df, df_out_vol)    

    return df_out_price, df_out_candle, df_out_vol
end