Reduce the BSK wheel size

[schaubh]

• Tickets addressed: bsk-814
• Review: By commit
• Merge strategy: Merge (no squash)

Description

When building a BSK wheel, the resulting file size is very large, over 200Mb. This is due to BSK including some data files into the resulting python package.

With the build process we already chose to download the large de430.bsp file from the JPL web link directly to reduce the GitHub repo size and bandwidth usage. This functionality is now expanded to all *.bsp files inside supportData/EphemerisData/*.bsp files.

Next, un-used data files have been removed. These files took up 10's of Mb.

Then, the wheel build process is updated to not include the supportData/EphemerisData/*.bsp files into the BSK package. This brings the wheel size to about 60-70 Mb depending on what build options were used (opNav, etc.).

Finally, to allow the user who installs BSK from a wheel to run existing BSK scripts, two new command line tools are included in the wheel. The first command bskLargeData pulls the missing *.bsp files and puts them into the locally installed BSK package. This allows existing BSK scripts to run without modification and retains the convenient nature of our BSK python package that includes basic data files. The user always has the option, of course, to connect custom data files to the BSK modules.

Next, the command bskExamples is included. When installing via a pip wheel none of the example tutorial scripts from the repo folder are available. The user could manually download these from GitHub. The command bskExamples pulls all the files inside the BSK root examples folder and installs them in the local directory of the user. This way a new user will be able to get up and running with BSK and tutorial scripts using only a few simple commands.

Verification

Did a lot of test builds to ensure the expected behaviors were achieved. The CI test that builds a wheel was updated to use bskLargeData so all the associated tests still pass.

Documentation

The pip install documentation is updated to talk about what is included in the BSK wheel, and how the bskLargeData and bskExamples commands can be used to install large data files and pull the examples folder.

Future work

None for now, but I'm sure this will be tweaked and updated over time.

[Mark2000]

Two questions about the changes:

• Does bskExamples automatically run bskLargeFiles? If not, that seems like it should be the default behavior.
• Do we know if people are often using the bsp files in their own projects? If the are and they install BSK from a wheel, will it be clear that they should run bskLargeFiles to get the files they are expecting? The behavior I would expect to see is if people try to load one of the now-removed files is a clear message that says "Run bskLargeFiles to download these files" or even better a prompt like "Do you want to download the bop support files? [y/n]".

[schaubh]

Thanks for the feedback. No, bskExamples does not run bskLargeData automatically. I could add that.

If the files are not present then we just get a standard Spice error message about not being able to load the expected file. I can look and see if we can insert another message suggesting to run bskLargeData. Not sure how helpful this is. I do want to make sure the final documentation makes this behavior very clear on what is included in a BSK wheel, and what can be added. The updated RST documentation on installing pip wheels is already updated.

[Mark2000]

The documentation is certainly good to have, but my philosophy is that is we can anticipate the issues the user may have, we should address it in the code. I think giving an additional message in the SPICE error would be helpful.

[schaubh]

Ok @Mark2000 , I added both changes. Now the command bskLargeData is run when bskExamples is run, documentation is updated, and if the gravity helper function can't find de430.bsp, a suggestion is made to run bskLargeData.

[Mark2000]

Looks good, I think those changes should be helpful.