Re: URL download and Cache problems
On 16 Dec 2004, at 08:56, Chipp Walters wrote: Dave Cragg wrote: Richard's thought may stem from a similar experience to mine. Previously, "load" was often preferred because it was the only way to show progress of the download, and not because there was a need to do other processing. In my own apps, I almost always need to pause other things until a download completes. (e.g. a learner chooses a lesson to open, and can't work on it until it has downloaded) "load" wasn't ideal for this. But "load" was often recommended over "get" because of this ability to show progress. With the libUrlStatusCallback option, I now rarely need to use load. It's much simpler to use get. I love libUrlStatusCallback! It also works great with POST and ftp uploads/downloads. Caveat: when using "get", there's no obvious way to abort a download before it completes. This should probably go on the to-do list. In my apps, I issue 'resetAll' which stops the download. Dave, you once mentioned a command something like libURLResetAll? I think it does the same thing. Then it's detention for you, Chipp. :-) All "resetAll" does is call libUrlResetAll. liburlResetAll is the "preferred and official" command. (Because there's a high chance someone has a library or stack script with a resetAll handler which does something completely unrelated, but more understandable such as resetting a set of preferences to their defaults.) Then I need to reinitialize my libUrlStatusCallback. This can present problems when calling from the IDE as it kills all socket activity for the engine everywhere, so best be careful. Be very careful! libUrlResetAll is a particularly brutal way to stop a download. I don't recommend it to anyone. For me, it's just a development tool and never include it in a distributed stack. But if anyone feels the need to include it in an app, be sure that libUrlResetAll is the last libUrl call in the handler where it appears. But until I add an official way to cancel a "get" download, here's a little tidbit. You can cancel a download by using this command: ulCancelRequest This is an internal handler used by libUrl during the "unload url" procedure. This handler alone should happily stop a "get" request too. WARNING: If you use this in a stack, be prepared to change it when a future libUrl release adds an official interface. Cheers Dave ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
At 08:31 16/12/2004 +, Dave Cragg wrote: On 15 Dec 2004, at 23:33, Alex Tweedly wrote: 3 if you count libURLDownloadToFile (though it's for ftp only) This works with http too. (Perhaps you were thinkig of libUrlFtpUploadFile.) No, I was thinking of libURLDownloadToFile, and believing what I read in the docs :-) First line of libURLDownloadToFile entry says Downloads a file from an Internet server asynchronously via FTP. Funny thing is, looking back at a couple of my stacks, I've used it to download via HTTP - but forgot that while writing that email. BZ entry coming soon -- Alex. ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
Dave Cragg wrote: Richard's thought may stem from a similar experience to mine. Previously, "load" was often preferred because it was the only way to show progress of the download, and not because there was a need to do other processing. In my own apps, I almost always need to pause other things until a download completes. (e.g. a learner chooses a lesson to open, and can't work on it until it has downloaded) "load" wasn't ideal for this. But "load" was often recommended over "get" because of this ability to show progress. With the libUrlStatusCallback option, I now rarely need to use load. It's much simpler to use get. I love libUrlStatusCallback! It also works great with POST and ftp uploads/downloads. Caveat: when using "get", there's no obvious way to abort a download before it completes. This should probably go on the to-do list. In my apps, I issue 'resetAll' which stops the download. Dave, you once mentioned a command something like libURLResetAll? I think it does the same thing. Then I need to reinitialize my libUrlStatusCallback. This can present problems when calling from the IDE as it kills all socket activity for the engine everywhere, so best be careful. -Chipp ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
On 15 Dec 2004, at 23:33, Alex Tweedly wrote: At 12:59 15/12/2004 -0800, Richard Gaskin wrote: This conversation raises a question - There are currently two ways to download files, the "load" command and "get URL". 3 if you count libURLDownloadToFile (though it's for ftp only) This works with http too. (Perhaps you were thinkig of libUrlFtpUploadFile.) It used to be the case that "load" was a better option for longer downloads and/or if you need to update a progress bar, since it was the only one of the two that was non-blocking and you could querty the urlStatus for those downloads. But now that we have the libUrlStatusCallback option, which provides periodic messages for "get URL", is there any benefit to using "load"? Yes, lots of them (I think). But they can all probably be summarized under one heading, i.e "load" is good when you need to get on with something else while the stuff is downloading. Richard's thought may stem from a similar experience to mine. Previously, "load" was often preferred because it was the only way to show progress of the download, and not because there was a need to do other processing. In my own apps, I almost always need to pause other things until a download completes. (e.g. a learner chooses a lesson to open, and can't work on it until it has downloaded) "load" wasn't ideal for this. But "load" was often recommended over "get" because of this ability to show progress. With the libUrlStatusCallback option, I now rarely need to use load. It's much simpler to use get. Caveat: when using "get", there's no obvious way to abort a download before it completes. This should probably go on the to-do list. Cheers Dave ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
At 12:59 15/12/2004 -0800, Richard Gaskin wrote: This conversation raises a question - There are currently two ways to download files, the "load" command and "get URL". 3 if you count libURLDownloadToFile (though it's for ftp only) It used to be the case that "load" was a better option for longer downloads and/or if you need to update a progress bar, since it was the only one of the two that was non-blocking and you could querty the urlStatus for those downloads. But now that we have the libUrlStatusCallback option, which provides periodic messages for "get URL", is there any benefit to using "load"? Yes, lots of them (I think). libURLSetStatusCallback provides you with periodic callbacks during (amongst other things) a get URL command. However, it would be a bit convoluted to carry on and do other processing from within such a callback; updating a progress bar/field would be fine, but going on to do more than that feels a bit complicated. Using load allows you to carry on with other general purpose processing of any kind, while still providing both periodic callbacks AND "when complete" callback. Also (if I read the docs correctly - haven't tried it), you cannot initiate a second blocking operation while the first one is still in progress (docs say this results in an error "Error Previous request not completed"). If you want to retrieve a number of URLs in parallel, the load command is still the only way. -- Alex. ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
This conversation raises a question - There are currently two ways to download files, the "load" command and "get URL". It used to be the case that "load" was a better option for longer downloads and/or if you need to update a progress bar, since it was the only one of the two that was non-blocking and you could querty the urlStatus for those downloads. But now that we have the libUrlStatusCallback option, which provides periodic messages for "get URL", is there any benefit to using "load"? -- Richard Gaskin Fourth World Media Corporation __ Rev tools and more: http://www.fourthworld.com/rev ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
On Dec 15, 2004, at 2:03 PM, Alex Tweedly wrote: put URL "http://www..."; into myVar Alex, That solved my problem. Thanks! Rick ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
At 13:41 15/12/2004 -0500, Rick Harrison wrote: On Dec 15, 2004, at 1:18 PM, Alex Tweedly wrote: Yes - simply use put URL "http://www..."; into myVar (or into a field, or wherever) Alex, Ok, but how does the program know when it is done downloading if I use: put URL "http://www..."; into myVar This one does wait until it's done (or has failed) The docs say: All actions that refer to a URL container are blocking: that is, the handler pauses until Revolution is finished accessing the URL. Since fetching a web page may take some time due to network lag, accessing URLs may take long enough to be noticeable to the user. To avoid this delay, use the load command (which is non-blocking) to cache web pages before you need them. -- Alex. ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
On Dec 15, 2004, at 1:18 PM, Alex Tweedly wrote: Yes - simply use put URL "http://www..."; into myVar (or into a field, or wherever) Alex, Ok, but how does the program know when it is done downloading if I use: put URL "http://www..."; into myVar Rick ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
At 13:05 15/12/2004 -0500, Rick Harrison wrote: Alex, I have some code that changes the URL correctly every time, so that is not the issue. I didn't want to list it because it takes up a lot of pages and is unnecessary for our discussion purposes. OK - understand. So the URL load doesn't wait to finish downloading the first file before downloading the second. Great..., that's just terrible for my purposes. What I really want is for one download to complete before it starts doing another. Is there anyway to do this? Yes - simply use put URL "http://www..."; into myVar (or into a field, or wherever) -- Alex. ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
On Dec 15, 2004, at 12:58 PM, Alex Tweedly wrote: At 12:28 15/12/2004 -0500, Rick Harrison wrote: Hi there, I'm getting some Revolution weirdness when trying to download files from the internet. Alex, I have some code that changes the URL correctly every time, so that is not the issue. I didn't want to list it because it takes up a lot of pages and is unnecessary for our discussion purposes. So the URL load doesn't wait to finish downloading the first file before downloading the second. Great..., that's just terrible for my purposes. What I really want is for one download to complete before it starts doing another. Is there anyway to do this? I haven't yet had time to digest your code yet. I'll get back to you a little later. Thanks for the quick response! Rick Harrison ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
Re: URL download and Cache problems
At 12:28 15/12/2004 -0500, Rick Harrison wrote: Hi there, I'm getting some Revolution weirdness when trying to download files from the internet. I don't think there's a real problem there, but I'm not sure, because it's hard to follow the description / script to be sure I'm correctly interpreting what you want. The basic issue is that the "load" command is non-blocking. So when you do the first "load URL" it does not (and should not) wait. It will accept any number of load commands, and queues them up (it probably fetches multiple of them in parallel, with some limit on how many it has under way at a time). I'm using: put "" into field "CachedURLSListField1" of card 1 put "" into field "ClearedCacheList1" of card 1 put 1 into N2 repeat while N2 < 4 load URL field "JPEGURL" of card 1 with message "downloadComplete" --(Which sends this message to the stack which I handle by updating a field with "Status - Download completed") export image "JpegImage" of card 2 to file field "ImageFileName1" of card 1 as JPEG -- Gets entire image put field "CachedURLSListField1" of card 1 & the cachedURLs into field "CachedURLSListField1" of card 1 --to list what files are in my cache --then I supposedly delete the cache with unload URL field "JPEGURL" of card 1 --and to check if the file was deleted out of the cache put field "ClearedCacheList1" of card 1 & the cachedURLs into field "ClearedCacheList1" of card 1 add 1 to N2 end repeat The problems I'm running into are the following: 1. The program doesn't wait until the first download is complete before moving on to the second download. That's good :-) 2. The cache isn't getting cleared Perhaps because you're clearing it (with unload) before that URL has finished being loaded; perhaps because there are multiple in-progress fetches, and you can never clear one without the next one appearing. 3. It's like Revolution is executing just too fast. The purpose of the load command is to act fast, and to allow your stack to continue with other work while the URLs are being pre-fetched. If you go ahead and use the URL before it has completely loaded, you'll still get the benefit. If I simply put answer "N2 = " & N2 -- before the end repeat everything downloads - but unfortunately, -- I have to be around to press the stupid button everytime to -- let the program move on, and I don't want to have to do that. Any ideas as to what is going on, and as to what I need to do to fix things? It's not clear just what you want to do, overall. It looks to me as though the loop is loading the same URL each time round - or am I missing something ? You might want to do something like local lNumberDone on gettheURLs put 0 into lNumberDone repeat while N2 < 4 load .. end repeat send checkifdone in 50 millisecs end gettheURLS on checkIfDone if lNumberDone = 4 then finished ... else send checkIfDone in 50 millisecs end if end checkIfDone on downloadComplete pURL, pURLStatus if pURLStatus = "Download Complete" then put URL pURL into (wherever you want it) else put "problem with " && pURL && ":" && pURLStatus & CR after field "myStatusfield" end if add 1 to lNumberDone end downloadComplete In summary - load is non-blocking. If this hasn't helped - send more of the script, or a fuller description of what you want. -- Alex. ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
URL download and Cache problems
Hi there, I'm getting some Revolution weirdness when trying to download files from the internet. I'm using: put "" into field "CachedURLSListField1" of card 1 put "" into field "ClearedCacheList1" of card 1 put 1 into N2 repeat while N2 < 4 load URL field "JPEGURL" of card 1 with message "downloadComplete" --(Which sends this message to the stack which I handle by updating a field with "Status - Download completed") export image "JpegImage" of card 2 to file field "ImageFileName1" of card 1 as JPEG -- Gets entire image put field "CachedURLSListField1" of card 1 & the cachedURLs into field "CachedURLSListField1" of card 1 --to list what files are in my cache --then I supposedly delete the cache with unload URL field "JPEGURL" of card 1 --and to check if the file was deleted out of the cache put field "ClearedCacheList1" of card 1 & the cachedURLs into field "ClearedCacheList1" of card 1 add 1 to N2 end repeat The problems I'm running into are the following: 1. The program doesn't wait until the first download is complete before moving on to the second download. 2. The cache isn't getting cleared 3. It's like Revolution is executing just too fast. If I simply put answer "N2 = " & N2 -- before the end repeat everything downloads - but unfortunately, -- I have to be around to press the stupid button everytime to -- let the program move on, and I don't want to have to do that. Any ideas as to what is going on, and as to what I need to do to fix things? Thanks in advance. Rick Harrison ___ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
