feat: Clean cache command

[d3xter666]

The command completely cleans the cache by removing the cache files as well as cleaning up the SQLite records.
It does not wipe out the SQLite DB file(s)

JIRA: CPOUI5FOUNDATION-891

[matz3]

I think the usability of the command could be improved.

• No information about the actual filesystem paths of the cache and relevant dirs (not in CLI description, not in --help, not in command output
• No information about the relation to ui5DataDir config / UI5_DATA_DIR env var
• No output when command is executed, and it might take a while to calculate the size, so users might assume the command is stuck if it does not print anything for a minute or longer.
• Output lists two different sizes 197.0 MB vs 196.8 MB:

The following items from cache will be removed:
  • buildCache/v0_7 (197.0 MB)

Total: 197.0 MB


✓ Removed buildCache/v0_7 (196.8 MB)

Success: Cleaned 1 entry, freed 196.8 MB

• (minor) Inconsistency in logged paths (framework/ vs framework):

The following items from cache will be removed:
  • framework/ (711.4 MB)

Total: 711.4 MB

Do you want to continue? (y/N) y

✓ Removed framework (711.4 MB)

[d3xter666]

I have tried to improve the situation with the infmration for the execution of the cache clean command and have addressed all your concenrns.

Let me know if there's something more you'd expect.

Regarding the size report, there are some considerations we need to be aware of:

• Getting framework cache dir size might require time. Even if you do that on your machine, it will take time. Even the du command on Mac uses cache in order to be quick, but the first run is not that fast. The optimal solution: Give information about the number of files that will be deleted
• The purge of the DB cache is just the opposite! Selecting COUNT(*) of all rows might take significant amount of time to get the results. On the other hand, the size of the DB can be quite fast.

I have tried to somehow get advantage of these findings and provide the optimal solution- show metrics for what is fast and provide generic messages. Any other solutions will require certain compromises.

[d3xter666]

Edit

Now the UX of this command is revised!

The real issue is enormous cache!

Collecting full information about what would be deleted is a haevy work and we simply cannot do it real time. In the end, for the end user it's important what would be deleted!
Given that, my proposal would be a summary information that does not need to collect all the files or their sizes. Instead, just put an overview:

Confirmation

Checking cache at /my/data/dir/.ui5 …

The following cached data will be removed:

  • UI5 Framework packages   /my/data/dir/.ui5/framework   (1 project, 18 libraries, 212 versions)
  • Build cache (DB)         /my/data/dir/.ui5/buildCache/v0_7   (100.0 KB)

Do you want to continue? (y/N)

During cache cleanup

If we now decide to accept purging of the hughe cache, it will take some time cleaning it up. We cannot do anythinbg about it, but simply wait for the fuiles to be deleted.
For that purpose, I have created an real time "monitor" of what is being deleted:

 ⠏ UI5 Framework packages   …/sap.m/1.52.14/src/sap/m/BarRenderer.js   2.86 s

Final summary

✓ Removed UI5 Framework packages   (/my/data/dir/.ui5/framework · 1 project, 18 libraries, 212 versions)
✓ Removed Build cache (DB)   (/my/data/dir/.ui5/buildCache/v0_7 · 100.0 MB)

Success: Cleaned UI5 Framework packages and Build cache (DB)

Hopefully, this is good enough as UX and fast enough, so that developers get feedback what is actually happenning

[RandomByte]

That's better. On my system it's very fast now:

Checking cache at /Users/me/.ui5 …

The following cached data will be removed:

  • UI5 Framework packages   /Users/me/.ui5/framework   (2 projects, 155 libraries, 1189 versions)
  • Build cache (DB)         /Users/me/.ui5/buildCache/v0_7   (70.7 MB)

Do you want to continue? (y/N) 

But I think the term projects is misleading here. Usually every UI5 app or library is a project. I would drop that entirely and rather say 1.189 versions of 155 libraries (ideally with a decimal separator?)

I don't really think we need a progress indicator for the deletion process. It is expected to take a while, I would rather not add code just for that.