UCM: How to create dynamic view (base clearcase) o

Question

Currently we use ClearCase UCM.. I am trying to evaluate possibility of using git in our project. I decided to create large repo with past three years changes from an integration stream. The pvob has 12 vobs under it. For purpose of evaluation(creating a worst case), I am putting all changes into single repository.

I want to create a base clearcase view and then adjust its spec for every baseline on the pvob. This will then synched to git repository.

Question in short: How can I create a base clearcase view given a pvob base line and keep changing its config spec to match every baseline?

(academic note : A picture of what I am trying to achieve.. )

(Approach discussed in ClearCase UCM: Is it possible to have a temporary view on any given baseline? is kind of work around in my case. I guess I can avoid the step of creating many temporary streams- not sure how!)

Answer 1

I am putting all changes into single repository.

This isn't the right granularity for a git repo.
Having done multiple ClearCase to Git migration, the right scale usually is one UCM component equals one Git repo.

How can I create a base clearcase view given a pvob base line and keep changing its config spec to match every baseline?

You don't have to create a base ClearCase view.
You can create a sub-stream to the Int stream, and manage the baselines you want to see there.
(cleartool rebase -bas xxx@\YourPVob)

You can then use an UCM view to that sub-stream as a source for your git import.

If that approach isn't possible (as I explained in my previous answer you mention, because for instance all baselines haven't been created in the same parent stream), then you can create a base ClearCase view and modify its config spec in order to select the baseline complete ids:

element * BaselineId1    
element * BaselineId2    
...

(A dynamic view here is more useful to tweak the config spec.
Once the config spec is set, you can update a snapshot view with the same config spec, and appropriate load rules, to use it as a source for your git import).

You need to make sure those baselines are:

• full baselines (you can promote an incremental one to a full one)

• referenced with their id (not their title, which is their visible name).
  See also "Display Current Baseline with Cleartool":

  cleartool describe -l baseline:aBaseline@\aPVob
  cleartool descr -fmt "%[found_bls]CXp" stream:myStream@\myPVob
  

The second command would give you all baselines in a stream.
In both cases, you would see the baseline ids in addition of their names.

---

I have mention the ClearCase to Git migration aspect in :

• "Migration from UCM ClearCase to GIT"
• "How to integrate ClearCase development history into Git?"
• "Save history from ClearCase to Git?"
• "How to bridge git to ClearCase?"
• "Sync GIT and ClearCase"

A good trick is to use:

git --git-dir=/path/to/git/repo/.git --work-tree=/path/to/ClearCase/view add .

That allows you to consider the ClearCase view as the working tree of your git repo (which is the destination of your import).

I generally don't try to import all baselines from all streams because it is too complex too soon (in order to get the sequence of those histories right).

I just get a few baselines from the main stream, import them and go from there (keeping the ClearCase referential as a read-only archive source for history research).