[mythtv-users] Myth on a Laptop

[R. G. Newbury]

Robert Johnston wrote:
> On 10/1/07, Yan Seiner <yan at seiner.com> wrote:
>> Brian Wood wrote:
>>> Yan Seiner wrote:
>>>
>>>> Several people have played with "Myth-to-go" over the years, myself
>>>> included.  There just doesn't seem to be enough critical mass, or a dev
>>>> with enough time and desire, to put it all together.  (I'm not
>>>> criticizing here; I'm one of those who has the need but not the time /
>>>> knowledge / desire to get it done.)
>>> I suspect there's a lack of a lot of interest.
>>>
>> Yup.
>>
>>> What might you want to do "on the go"?
>>>
>>> Watch recordings? You can do that easily by just transferring the files.
>>>
>>> Schedule recordings? You can do that now with a web browser.
>>>
>>> You can grab any recordings not already on the laptop over the net.
>>>
>>> Anything having to do with optical media would require physical access
>>> to the main machine.
>>>
>>> Maybe tuning and watching live TV (a la Slingbox) would be desired, but
>>> by how many?
>> Well, the original concept involved adding a "to go" interface where you
>> can pick movies and recordings to transfer to the 'to go' box.  The
>> plugin then rsyncs those recordings over, extracts the appropriate data
>> from the master BE SQL database, and stuffs it into the remote BE SQL
>> database.
>>
>> That way, when you unplug from the network and reboot, Myth comes up,
>> automagically fires up its own BE and SQL database, and has the correct
>> data in the database to watch what you want.
>>
>> The whole idea is "disconnected operation" rather than "remote
>> operation".  We travel a lot, and take movies for the kids (and us) on a
>> small PC.  This way we can play what we want, with no need for
>> connectivity to the web.
> 
> Just throwing an idea out here:
> 
> For the recordings, you could use NFS and UnionFS, so you have a
> "Local" copy of the recordings, and use UnionFS to "Merge" those with
> NFS-Mounted recordings from the actual backend. Then, when you
> disconnect, the NFS mount disappears, but you still have the
> recordings copied to the "Local" folder available.
> 
> Unfortunately, the Database is going to be a problem - MySQL's
> Replication is poor to say the least, and it wouldn't help distinguish
> what is available when the laptop's "Offline". Perhaps having the
> mysql.txt be a link to a version within the UnionFS that gets
> overridden by the NFS mount.
> 
> Then all that would need working out is the copying (And deletion) of
> the local SQL entries when a recording is "Exported", and starting
> (and stopping) MythBackend on the "Disconnected" laptop to take over
> backend duties when the network connection goes down.
> 
> Just a thought, anyways.

This should be do-able, but not trivial to do. It really depends on 
being able to get a 'playlist' on the 'home' system. Code to do part of 
that may already exist in mytharchive. A script would then, create a 
mysqldump of the necessary lines from the 'recorded' table, and as well 
create a copy/rsync script to copy the playlist programs to the laptop, 
together with the database lines. On the laptop, another script would 
update the mysql database. I suspect it would not be possible to have 
the laptop act as a frontend to the home machine, unless the laptop was 
scripted to act as a pure BE/FE or to act as a FE only. Might need 
different mythconverg databases and two parallel FE setups...Tricky!

None of the steps above are particularly difficult, but mind-numbing if 
you are dealing with a couple of files..

Geoff