1 00:00:00,179 --> 00:00:05,359 Great, we are in version two and I'll try to be quick now and show you version 3. 2 00:00:05,359 --> 00:00:11,370 This is version 3 the way I implemented this functionality where I want to check 3 00:00:11,370 --> 00:00:17,160 if there is an address column in the data frame is by adding a try and expect 4 00:00:17,160 --> 00:00:26,400 segment so basically if you can see the difference is I get the file and then I 5 00:00:26,400 --> 00:00:34,680 try to read that file or this this could also be outside of the try keywords that 6 00:00:34,680 --> 00:00:39,840 wouldn't be a problem and GC outside of the try keyword as well. However this is 7 00:00:39,840 --> 00:00:46,140 still better because you may also want to check for user sending files that 8 00:00:46,140 --> 00:00:51,960 are not csv, so here we're checking actually that the user is submitting a 9 00:00:51,960 --> 00:00:58,770 CSV file however that only means that the file has a dot csv extension in the 10 00:00:58,770 --> 00:01:05,309 file name, however that doesn't mean that the file is actually csv, so you may 11 00:01:05,309 --> 00:01:11,490 have let's say an mp4 file and you have changed that the extension to csv but 12 00:01:11,490 --> 00:01:17,220 that's still an mp4 file, so what you want to do is you want to include DF 13 00:01:17,220 --> 00:01:23,850 inside the try and expect block. If Python is not being able to create a data frame 14 00:01:23,850 --> 00:01:29,460 out of an mp4 file, then it will throw an error so that's what 15 00:01:29,460 --> 00:01:33,900 actually happens if you pass on an mp4 file. You wouldn’t be able to read it 16 00:01:33,900 --> 00:01:42,140 as a data frame, so yeah you want to include that in here and then you return 17 00:01:42,140 --> 00:01:47,390 the same so I haven't changed anything here, you return the same template 18 00:01:47,390 --> 00:01:54,119 index.html and send the HTML there and the button, except if there is an error what 19 00:01:54,119 --> 00:01:59,729 you do is you return the index dot HTML but then instead of the HTML table you want 20 00:01:59,729 --> 00:02:05,369 to return this message and of course you don't want to return any download 21 00:02:05,369 --> 00:02:10,860 button in there and yeah that should do it. And that's about version 3 so 22 00:02:10,860 --> 00:02:18,540 those are, those were the differences. Now version 4, what I have there? Well if you 23 00:02:18,540 --> 00:02:26,100 see here we got this geocoded.csv file, now that's a string and that means 24 00:02:26,100 --> 00:02:31,200 that a geocoded.csv file will be created for all the users that will 25 00:02:31,200 --> 00:02:37,650 be submitting data. Now that may cause some problems because if two users are 26 00:02:37,650 --> 00:02:43,860 submitting data at the same time you may have some name clashes there. So what did 27 00:02:43,860 --> 00:02:50,070 you do here is you could use a date/time module to generate unique names for 28 00:02:50,070 --> 00:02:57,090 every generated file and that's what I did so here is version 4. I imported 29 00:02:57,090 --> 00:03:04,770 the date/time module in here and then I'm generating the geocoded csv file 30 00:03:04,770 --> 00:03:12,900 in here so DF to csv file name and I made this fine line global in here 31 00:03:12,900 --> 00:03:20,010 because I also want to access it from the download function in here, so again I 32 00:03:20,010 --> 00:03:25,200 want to generate that in here I'm generating a file name and then in the 33 00:03:25,200 --> 00:03:31,080 file name we have the upload string which will point to the 34 00:03:31,080 --> 00:03:36,900 directory where will this file will be. Then we have the slash and actually this 35 00:03:36,900 --> 00:03:43,890 plus shouldn't be there so just after the slash we have the file name and that 36 00:03:43,890 --> 00:03:49,950 would be, you know we have the year, and then we have the month, and then the day and 37 00:03:49,950 --> 00:03:55,290 then the hour and the minutes, and seconds, and milliseconds, and then the 38 00:03:55,290 --> 00:04:02,519 dot CSV extension in the file name. So yeah this is quite unique for every 39 00:04:02,519 --> 00:04:05,810 user because we have milliseconds in there. 40 00:04:05,810 --> 00:04:13,440 But let me show you how this looks like actually, so again the user chooses 41 00:04:13,440 --> 00:04:19,200 a file submit and when I press submit Python will generate that data frame 42 00:04:19,200 --> 00:04:26,760 and it will also generate this csv file so in this line here and 43 00:04:26,760 --> 00:04:32,310 you can now find that csv file in the uploads folder so this was this was 44 00:04:32,310 --> 00:04:38,030 generated earlier and this is the file. That's the file that we just generated. 45 00:04:38,030 --> 00:04:45,150 Then when the user presses download the file will be downloaded but with your 46 00:04:45,150 --> 00:04:51,510 file name which is this one here. Yeah, what happens is that the download 47 00:04:51,510 --> 00:04:56,670 function will get the path of the file that that it has to download in the 48 00:04:56,670 --> 00:05:03,480 browser will get the file name from of this global variable. that's why I'm 49 00:05:03,480 --> 00:05:08,100 passing this as a global variable so that I can access the value of it which 50 00:05:08,100 --> 00:05:15,000 is generated in here, I can access this value from another function and yep 51 00:05:15,000 --> 00:05:20,520 that's my version of the application. I know this is not like your version. 52 00:05:20,520 --> 00:05:24,930 I hope you are close as much as possible! I think it would be great if you 53 00:05:24,930 --> 00:05:30,750 you did it better than me. In either case I'm sure that trying to solve this 54 00:05:30,750 --> 00:05:37,200 application should have improve your problem-solving skills in Python because 55 00:05:37,200 --> 00:05:42,990 that at least will position you so will define your level, your Python level so 56 00:05:42,990 --> 00:05:46,020 that you can fill the gaps that you really think are not your strongest 57 00:05:46,020 --> 00:05:52,000 points. And yeah, that was about this lecture and I'll see you.