Magma itself supports persisting change-sets via the following API:
============== "file-out a ChangeSet" mySession commit: [ mySession codeBase fileOutChangeSet: (ChangeSorter changeSetNamed: 'myChangeSet') ]
"Load a ChangeSet" mySession codeBase fileInChangeSetNamed: 'myChangeSet'
"browse a change-set before filing it in" mySession codeBase browseChangeSetNamed: 'myChangeSet'
"Answer a collectioon of all changeSet names in the codeBase." mySession codeBase changeSetNames
"Install all the changeSets in the codeBase immediately." mySession codeBase installChangeSets ===============
But I didn't do anything to integrate methods stored in change-sets this way into the new MC History function.
Seems like it would be a neat thing to do though if someone had the time..
On Sat, Dec 7, 2013 at 5:54 PM, David T. Lewis lewis@mail.msen.com wrote:
On Sat, Dec 07, 2013 at 04:58:51PM -0600, Chris Muller wrote:
I thought about it 4 years ago and made an object model to take care of it. The problem with zip-files is how wasteful they are. When someone changes one single method of the Morphic package, the other 1K definitions (however many there are) are duplicated in new zip (mcz) file. By contrast, the object model refers to the same canonicalized MCDefinition instances across Versions, adding only one new MCDefinition to the bulk of the model in that example.
The result is that the redundant Magma-backed copy of source.squeak.org consumes less than 1/4th the space of the original File based version. A Magma-backed copy of squeaksource.com would about 12GB of space.
PS -- For interest, I just kicked off a bulk-load of entire squeaksource.com repository into Magma to see how much space it will take..
I changed the subject line, and am moving the discussion over to squeak-dev because I think it may be of more general interest.
I'm quite interested to know how that turns out. Entirely aside from disk space concerns, the approach you are describing makes a lot of sense to me, and the squeaksource.com archive provides a fairly large data set to try it out.
Bob Arning has been doing some really interesting things with a Seaside browser for exploring the change set records of earlier Squeak development. Meanwhile you (Chris) are doing equally interesting work to enable a Monticello browser to browse through the historical record of source.squeak.org, backed up a Magma-enabled image currently running on box4.squeak.org:8888.
I have a of vague hand-waving notion that these two should be related, and that if I wanted to figure out how some method in e.g. ObjectMemory came into being, it would be really convenient if I could explore its change history to see various things that Eliot or Tim or I might have done in recent years in the Monticello repositories, and continue back in time through the change set update stream to see how and why Dan Ingalls might have originally implemented it in Squeak 1.x.
Is there some way in which the change set based update stream from earlier Squeak could also be captured in the Magma back end, similar to what you are doing with the Monticello packages?
Dave