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refresh_on_demand [2012/04/27 14:27]
jhb50
refresh_on_demand [2012/08/06 14:06] (current)
jhb50
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- **HOW TO REFRESH ONLINE FOLDERS ON DEMAND FROM THE CLIENT** +**HOW TO REFRESH ONLINE FOLDERS ON DEMAND FROM THE CLIENT**
- +
-NOTE:- This is currently in the middle of being modified  4/27/2012 +
  
 __THE NEED FOR REFRESH ON DEMAND__ __THE NEED FOR REFRESH ON DEMAND__
  
-Serviio will automatically refresh the content online sources (feeds), with each restart and on a periodic basis according to the "Feed expiry interval (hours)" set in the console.  This is adequate for Online Sources that are relatively static, but there are some sources (feeds)that are dynamic, with their feed items constantly changing, so the feed must be refreshed in order for Serviio to obtain and display the latest set of feed items.  Sports Event sites such as HaHaSport and News sites such as Video.AP are two examples of this.+By default, Serviio will automatically refresh the content "Online sources("feeds"), with each restart and on a periodic basis according to the "Feed expiry interval (hours)" set in the console.  This is adequate for "Online Sourcesthat are relatively static, but there are some Online sources("feeds") that are dynamic, with their "feed itemsconstantly changing, so the "feedmust be refreshed in order for Serviio to obtain and display the latest set of "feed items".  Sports Event sites such as HaHaSport and News sites such as Video.AP are two examples of this.
  
 There are two ways to initiate those more frequent refreshes. There are two ways to initiate those more frequent refreshes.
  
-One approach is to create a WebResource groovy for the feed and set the expiry date to initiate refreshes of that feed on periodic basis consistent with the known dynamics of the source for example just before the start of the next scheduled sports event or every 30 minutes for a news feed. +One approach is to create a WebResource groovy for the feed and set the expiry date to initiate refreshes of that feed on periodic basis consistent with the known dynamics of the source for example just before the start of the next scheduled sports event or every few minutes for a news feed. 
  
-The Online Source HAHASPORT.COM is an example. This site maintains and provides a list of scheduled events by sport, and provides links to embedded player streams of events as they go live. To maintain currency of a Serviio menu, the list of scheduled events must be reviewed at least hourly since new events can be added or removed at any time; live events must be detected minutes prior to their scheduled start, and if not yet started, again at their scheduled start and a few minutes thereafter; and then live events must be removed a few minutes after their scheduled end time. +The Online Source ("feed"HAHASPORT.COM and its WebResource groovy is an example. This site maintains and provides a list of scheduled events by sport, and provides links to embedded player streams of events as they go live ("feed items"). To maintain currency of a Serviio menu, the list of scheduled events must be reviewed by the groovy at least hourly since new events ("feed items"can be added or removed at any time; live events ("feed items"must be detected minutes prior to their scheduled start, and if not yet started, again at their scheduled start and a few minutes thereafter; and then live events ("feed items"must be removed a few minutes after their scheduled end time. 
  
-The problem with this approach is the continual use of resources to refresh and maintain the current set of feed items even though they may never be used. Secondly, this constant stream of refreshes particularly when multiple sport feeds are enabled, is beyond the capacity of most systems and feed refreshes are constantly backlogged due to insufficient time to access the changing feed items.+The problem with this approach is the continual use of resources by the groovy to refresh and maintain the current set of feed items even though they may never be used. Secondly, this constant stream of refreshes particularly when multiple sport feeds are enabled, is beyond the capacity of most systems and feed refreshes are constantly backlogged due to insufficient time to access the changing feed items.
  
-The better approach is to be able to "Force Refresh" a feed just prior to its use. However the problem with this approach is that if a significant number of new feed items have been created since the previous refresh, it may take Serviio many minutes to refresh and make the feed available again. Another problem is that while the Serviio Server Console and various Remote Device Console implementations offer the ability to "Force Refresh" Online Sources On Demand, no capability is offered to initiate a "Force Refresh" on demand from the menus on a Client device.+The better approach is to be able to "Force Refresh" a feed just prior to its use. However the problem with this approach is that if a significant number of new feed items have been created since the previous refresh, it may take Serviio many minutes to refresh and make the feed available again, since each new item can take 30 seconds or more to add. Another problem is that while the Serviio Server Console and various Remote Device Console implementations offer the ability to "Force Refresh" Online Sources On Demand, no capability is offered to initiate a "Force Refresh" on demand from the menus on a Client device. so users must access the server or obtain a device which has 3rd party remote console support.
  
-The ultimate solution therefore is to implement those dynamic feeds with a Web Resource that refreshes on a periodic basis that will minimize the number of new feed items to be added by a "Force Refresh", and to provide a "Force Refresh" capability from the menus on the client device, that may be used just prior to using the feed. +The ultimate solution therefore is to implement these dynamic feeds with a Web Resource that refreshes on a periodic basis in order to minimize the number of new feed items that will need to be added by a "Force Refresh", and to provide a "Force Refresh" capability from the menus on the client device, that may be used just prior to using the dynamic feed. 
  
-The facility to initiate periodic refreshes more frequently than the console default refresh value is documented in the "Serviio Online Resource plugin implementation Guide" under "Date expiresOn" Date is based on the current time {long curTimea = System.currentTimeMillis()} plus the milliseconds to the desired expiry time. Note that expiry will be on the earliest of that Date and the console default, and the refresh will actually be performed by Serviio 5 minutes ahead of that time. +The facility to initiate periodic refreshes in a Web Resource plugin groovy, more frequently than the console default refresh valueis documented in the "Serviio Online Resource plugin implementation Guide" under "Date expiresOn" Date is based on the current time {long curTimea = System.currentTimeMillis()} plus the milliseconds to the desired expiry time. Note that expiry will be on the earliest of that Date and the console default, and the refresh will actually be performed by Serviio 5 minutes ahead of that time. 
  
-The facility to initiate "Force Refresh" from the menus on the client device is documented below, and consists of WebResource RefreshWebResources.groovy that generates a menu of "Force Refresh" feed items for all WebResource feeds in the Serviio librarywhich allows one or more feeds to be refreshed on demand, and "forcerefresh" method that may be included in any WebResource groovy to create a "Force Refresh" feed item within the Webresource menu itself.+The hahasports.groovy implements this option via a refresh=nnn parameter that removes the automatic refresh based on event times and only refreshes the feed every nnn minutes. Other dynamic feeds should implement similar capability"Force Refresh" from the server or a remote console, or from client device menu may then be used to refresh the feeds prior to opening them
  
-Consistent with this approach the HAHASPORT.GROOVY implements an automatic expires on refresh every 60 minutes plus the method which creates a "Force Refresh" feed item and may be reviewed as an example of the methodology.+The facility to initiate "Force Refresh" from an online menu on a client device consists of a WebResource Refresh.groovy that generates a menu of "Force Refresh" feed items for all enabled WebResource feeds in the Serviio online library. Clicking on a listed feed item initiates a "Force Refresh" of that feed by intercepting the call to play the video associated with that menu item. The feed is then removed from the list of Online menu feeds while it refreshes and it becomes available again by opening the Online menu once the refresh is complete. The implementation is documented below.
  
 __ON DEMAND METHODOLOGY__ __ON DEMAND METHODOLOGY__
  
-The ability to implement "Force Refresh" feed items in the RefreshWebResources.groovy or the "forcerefresh" method in any WebResource is based on prerequisite implementations:+The ability to implement "Force Refresh" feed items in the Refresh.groovy is based on prerequisite one time implementations:
  
-1) The installation of CURL.EXE which provides the abilty to +1) The installation of CURL.EXE which provides the abilty to access the Serviio repository data and initiate forced refreshes per the latest "Serviio REST interface specification.pdf" The curl.exe may be obtained from http://curl.haxx.se/dlwiz/?type=bin and use the wizard to select the correct package for your operating system and install it in the appropriate system library. I used the generic Win64-ssl package and copied curl.exe into C:\windows\sysWOW64. W32 users should get the generic Win32 package and copy curl.exe into C:\windows\system32
  
-The prerequisite is the development of a WebResource groovy for the online source and the identification of a permanently available online source link that may be used to provide a Refresh Menu Item stream.+2) The availability of a live Stream URL which can be used as the trigger to initiate calls to curl.exe to initiate individual library refresh requests. The live Stream URL for the International Space Station (ISS) feed %%"rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/vnnn/reflector:53708"%% is currently used by RefreshWebResources.groovy as the live stream associated with each "Force Refresh" feed item, where the "v Value" nnn is the online library id to be refreshed.
  
-The WebResource groovy should create the Refresh item as the first menu item, using an appropriate thumbnail and title and the Refresh Menu item stream+3) The availability of a "Force Refresh" icon to be used by RefreshWebResources.groovy for each "Force Refresh" "feed item" associated with the ISS live stream. The icon %%https://sites.google.com/site/serviiorss/refresh.jpg%% is currently used which displays "CLICK TO REFRESH FOLDER" and the "feed item" title is used to display any additional information.
  
-If it is desired to automatically refresh the folder more frequently than the default expiry time in the console, the WebResource groovy should also generate a value for "expires onfor at least one of the items equal to that value + 5 minutes else Serviio will automatically refresh using the console value(Note that Serviio will not allow expiry to be deferred beyond the console period.)+4) The addition of the line -Dffmpeg.location="C:\Program Files\Serviio\lib\ffmpeg.bat" to the file C:\Program Files\Serviio\bin\ServiioService.exe.vmoptions to cause all Serviio ffmpeg calls to be sent to ffmpeg.bat  This needs to be repeated after each Serviio new installwhich will restore that file. 
 +After the addition it will contain: 
 +<code>-Xmx512m 
 +-Dffmpeg.location="C:\Program Files\Serviio\lib\ffmpeg.bat" 
 +</code> 
 +5) The installation of the attached ffmpeg.bat as C:\Program Files\Serviio\lib\ffmpeg.bat which will detect the ffmpeg calls containing the ISS URL, extract the "vValue" nnn and issue the curl command to refresh the Serviio online library nnn, before calling ffmpeg to process the original ffmpeg call. Note the ffmpeg.bat also logs each ffmpeg call in C:\Program Files\Serviio\log\ffmpeg.log which I have found useful for debugging. The bat may be edited to comment out that line as noted in the bat.
  
-The ServiioService.exe.vmoptions file also needs to be edited to cause ffmpeg.exe transcoding requests to be sent to a script which first checks for the link to the Refresh Menu item stream and initiates an Online Library Refresh of the appropriate library id using CURL before calling ffmpeg.exe to transcode the requested stream.+6) The addition of WebResource to the Library Online Sources section of the console using the dummy url http://www.refresh.com
  
-Finally the script needs to be edited to define the library id and the corresponding Refresh Menu Item stream urlso that the correct library is refreshed when the Refresh Menu item is clicked.+With these changes, a Refresh menu will be created with items showing the library id and name of each active Web Resource online source together with a "Click to Refresh Folder" icon. Clicking on an iteminitiates playback of the ISS stream while the feed refreshes. Note that a refresh can require up to 30 seconds to cache a new item, but with hourly automatic updates many of the new events should already be cached. After waiting an appropriate period, playback may be stopped, the Refresh and Online Folders exited, and the Online Folder reopened. If the refresh is complete the Refreshed folder should appear. If not repeat the closing and reopening of the Online Folder until it does.
  
-__THE HAHASPORT IMPLEMENTATION__+__The FFMPEG.BAT - Updated for Serviio 1.0__ 
 +Download {{:ffmpeg.bat.zip}}
  
-The HAHASPORT.GROOVY uses the c- value designating the sport from the ResourceUrl eg:%%http://www.hahasport.com/c-1.html%% to request different Refresh Menu item streams for each sport. Similarly the script checks for each of these streams to determine the online library id to refresh.+**How to setup Refresh on demand from client for Linux and Synology NAS:** [[refresh_on_demand_linux|refresh_on_demand_linux]]
  
-The HAHASPORT.GROOVY uses "%%https://sites.google.com/site/serviiorss/refresh.jpg%%" as the thumbnail, "Click to Refresh" as the videotitle and "%%rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/vn/reflector:53708%%" (which is the view from the ISS) as the Refresh Menu item stream where the n in vn corresponds to the c- value in the ResourceUrl. 
- 
-With these changes clicking on the Refresh menu item, initiates a refresh of the corresponding online source while the Refresh Menu Item stream plays. If one waits for the refresh to complete before stopping playback, the refreshed menu will be displayed on return and the desired item selected for playback, else the menu will be unavailable on return and Serviio will exit and require a restart to access the updated menu once available. (Note that a refresh can require up to 30 seconds to cache a new item, but with hourly automatic updates many of the events should already be cached). 
- 
-The HAHASPORT.GROOVY is dependent upon the attached ffmpeg.bat script with the appropriate online library id's added as determined by using CURL to dump the repository as documented in the script, and the script is similarly dependent upon the change to ServiioService.exe.vmoptions as documented in the script. (Note I am sure more advanced scripts can be created by those conversant with other scripting tools than bats) 
- 
-After listing the available live streams, the HAHASPORT.GROOVY also generates a final item in each menu, showing either the scheduled start time of the next event or the absence of any more events in the schedule for that sport, along with the time of the next automatic refresh. 
- 
-__USING THE HAHASPORT GROOVY__ 
- 
-To use the HAHASPORT.GROOVY {{:hahasport.groovy.V2.zip}} just add the following Resource URL's as WebResources in the Serviio Console, together with the appropriate labels. 
- 
-%%http://www.hahasport.com/c-1.html%%  FOOTBALL 
-%%http://www.hahasport.com/c-3.html%% HOCKEY 
-%%http://www.hahasport.com/c-4.html%% TENNIS 
-%%http://www.hahasport.com/c-6.html%% BASKETBALL 
-%%http://www.hahasport.com/c-7.html%% BASEBALL 
-%%http://www.hahasport.com/c-8.html%% GOLF 
-%%http://www.hahasport.com/c-9.html%% CYCLING 
-%%http://www.hahasport.com/c-10.html%% MOTORSPORTS 
-%%http://www.hahasport.com/c-11.html%% OTHER 
- 
-Since each live event may have multiple streams available, each from a different source, an estreams parameter may be used with the ResourceUrl to cause multiple streams to be displayed for each live event if available. estreams may equal 1 thru 9 with 9 signifing that all available streams should be displayed, for example %%http://www.hahasport.com/c-1.html?estreams=9%% 
- 
-Note also that since HAHASPORT.COM sources its streams from many different sources, there may be live streams that the groovy does not decode for display in the Serviio menu. For details on the stream decoding set the onlinelibrary log to debug mode. 
- 
-To access the current events for a given sport, open the menu and click on the Refresh menu item which will initiate a refresh of the online source while the Refresh Menu Item stream plays. Wait for the refresh to execute (30 seconds per new item) before stopping playback and the refreshed menu will be displayed on return and the desired item selected for playback. If playback of the Refresh Menu Item stream is stopped before the refresh is complete the menu will be unavailable on return and Serviio will exit and require a restart to access the updated menu once available. 
- 
-Note that if you do not to implement the changes required to support the Refresh On Demand menu item, you must use the Serviio console or a remote console to force the refresh of each sport in order to obtain the current live stream event menu. 
- 
-__THE SCRIPT__ 
- 
-<code> 
-@echo off 
-: 
-: To intercept Serviio FFmpeg Calls install this bat as "C:\Program Files\Serviio\lib\ffmpeg.bat" 
-: then Edit "C:\Program Files\Serviio\bin\ServiioService.exe.vmoptions"  
-: and change the Dffmpeg.location variable to 
-: -Xmx384m 
-: -Dffmpeg.location="C:\Program Files\Serviio\lib\ffmpeg.bat" 
-: 
-: Finally install Curl as required in C:\windows\system32 and use 
-: Curl -X GET "http://localhost:23423/rest/repository"  > C:\temp\repository.txt 
-: to get the online repository ids for each c- value in http://www.hahasport.com/c-n.html  
-: and enter the ids in the table below. eg: set C1=54 
- 
-set C1=  
-set C2= 
-set C3=  
-set C4=  
-set C5= 
-set C6=  
-set C7= 
-set C8=  
-set C9= 
-set C10= 
-set C11=  
- 
-: The following code will then be executed before passing control back to Serviio's ffmpeg. 
- 
-set A=%1 
-shift 
-set B=%1 
-shift 
-set C=%1 
-shift 
-set D=%1 
-shift 
-set E=%1 
-shift 
-set F=%1 
-shift 
-set G=%1 
-shift 
-set H=%1 
-shift 
-set I=%1 
-shift 
-set J=%1 
-shift 
-set K=%1 
-shift 
-set L=%1 
-shift 
-set M=%1 
-shift 
-set N=%1 
-shift 
-set O=%1 
-shift 
-set P=%1 
-shift 
-set Q=%1 
-shift 
-set R=%1 
-shift 
-set S=%1 
-shift 
-set T=%1 
-shift 
-set U=%1 
-shift 
-set V=%1 
-shift 
-set W=%1 
-shift 
-set X=%1 
-shift 
-set Y=%1 
-shift 
-set Z=%1 
-shift 
-set AA=%1 
-shift 
-set BB=%1 
-shift 
-set CC=%1 
-shift 
-set DD=%1 
-shift 
-set EE=%1 
-shift 
-set FF=%1 
-shift 
-set GG=%1 
-shift 
-set HH=%1 
-shift 
-set II=%1 
-shift 
-set JJ=%1 
-shift 
-set KK=%1 
-shift 
-set LL=%1 
-shift 
-set MM=%1 
-shift 
-set NN=%1 
-shift 
-set OO=%1 
-shift 
-set PP=%1 
-shift 
-set QQ=%1 
-shift 
-set RR=%1 
-shift 
-set SS=%1 
-shift 
-set TT=%1 
-shift 
-set UU=%1 
-shift 
-set VV=%1 
-shift 
-set WW=%1 
-shift 
-set XXY=%1 
-set CODE=NONE 
-echo %A% %B% %C% %D% %E% %F% %G% %H% %I% %J% %K% %L% %M% %N% %O% %P% %Q% %R% %S% %T% %U% %V% %W% %X% %Y% %Z% %AA% %BB% %CC% %DD% %EE% %FF% %GG% %HH% %II% %JJ% %KK% %LL% %MM% %NN% %OO% %PP% %QQ% %RR% %SS% %TT% %UU% %VV% %WW% %XX% %YY% %ZZ% >> "C:\Program Files\Serviio\log\ffmpeg.log" 
-:COM Note Serviio appends ?tcp to rtsp links. 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v1/reflector:53708?tcp set CODE=%C1% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v2/reflector:53708?tcp set CODE=%C2% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v3/reflector:53708?tcp set CODE=%C3% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v4/reflector:53708?tcp set CODE=%C4% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v6/reflector:53708?tcp set CODE=%C6% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v7/reflector:53708?tcp set CODE=%C7% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v8/reflector:53708?tcp set CODE=%C8% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v9/reflector:53708?tcp set CODE=%C9% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v10/reflector:53708?tcp set CODE=%C10% 
-if .%B% == .rtsp://a1709.l1856953708.c18569.g.lm.akamaistream.net:554/D/1709/18569/v11/reflector:53708?tcp set CODE=%C11% 
-::if .%CODE%==.NONE "C:\Program Files\Serviio\lib\ffmpeg.exe" %A% %B% %C% %D% %E% %F% %G% %H% %I% %J% %K% %L% %M% %N% %O% %P% %Q% %R% %S% %T% %U% %V% %W% %X% %Y% %Z% %AA% %BB% %CC% %DD% %EE% %FF% %GG% %HH% %II% %JJ% %KK% %LL% %MM% %NN% %OO% %PP% %QQ% %RR% %SS% %TT% %UU% %VV% %WW% %XX% %YY% %ZZ% 
-if NOT .%CODE%==.NONE echo REFRESH %CODE% >> "C:\Program Files\Serviio\log\ffmpeg.log" 
-if NOT .%CODE%==.NONE curl -X POST "http://localhost:23423/rest/action" -H "Content-Type: text/xml" -d "<action><name>forceOnlineResourceRefresh</name><parameter>%CODE%</parameter></action>" 
-"C:\Program Files\Serviio\lib\ffmpeg.exe" %A% %B% %C% %D% %E% %F% %G% %H% %I% %J% %K% %L% %M% %N% %O% %P% %Q% %R% %S% %T% %U% %V% %W% %X% %Y% %Z% %AA% %BB% %CC% %DD% %EE% %FF% %GG% %HH% %II% %JJ% %KK% %LL% %MM% %NN% %OO% %PP% %QQ% %RR% %SS% %TT% %UU% %VV% %WW% %XX% %YY% %ZZ% 
-exit 
- 
-</code> 
  
refresh_on_demand.1335536842.txt.gz · Last modified: 2012/04/27 14:27 by jhb50