[SDK] Train API

[deepanker13]

What this PR does / why we need it:

1. This pr contains the train api function which will be called by the user to run the training job.
2. Constants have been added to access them at multiple places.

Which issue(s) this PR fixes (optional, in Fixes #<issue number>, #<issue number>, ... format, will close the issue(s) when PR gets merged):
Partially Fixes #1945

Checklist:

• Docs included if any changes are user facing

[coveralls]

Pull Request Test Coverage Report for Build 7477774579

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.01%) to 42.896%

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Totals
Change from base Build 7477136161:	0.01%
Covered Lines:	3756
Relevant Lines:	8756

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💛 - Coveralls

[deepanker13]

/hold depends on #1959 and #1958

[deepanker13]

/hold cancel

[andreyvelich]

/assign @andreyvelich
@deepanker13 Please can you rebase this PR ?

[andreyvelich]

Thank you for this @deepanker13 !

[deepanker13]

/assign @andreyvelich
@deepanker13 Please can you rebase this PR ?
done

[deepanker13]

@andreyvelich I have a reason to keep the download dir field, as there will be a single place where we define the default value and that same value will be passed through the code flow, else we will have to verify the values are same or not through the entire code flow.

[andreyvelich]

Let's name the directory storage_initiailizer rather than storage_init_container to be consistent with init container name ?
WDYT @deepanker13 ?

[andreyvelich]

@andreyvelich I have a reason to keep the download dir field, as there will be a single place where we define the default value and that same value will be passed through the code flow, else we will have to verify the values are same or not through the entire code flow.

@deepanker13 Can you just have 3 constant variables in storage_initializer/constants.py:

INIT_CONTAINER_MOUNT_PATH = "/workspace"
VOLUME_PATH_DATASET = INIT_CONTAINER_MOUNT_PATH + "/dataset"
VOLUME_PATH_MODEL = INIT_CONTAINER_MOUNT_PATH + "/model"

And then just re-use these constants in SDK and storage_initializer.
Does it work for you @deepanker13 ?

[andreyvelich]

I think, we are ready to merge this PR.
Thanks again @deepanker13 for all of this work!
/lgtm
/assign @johnugeorge @tenzen-y for the final review.

[deepanker13]

I think, we are ready to merge this PR.
Thanks again @deepanker13 for all of this work!
/lgtm
/assign @johnugeorge @tenzen-y for the final review.

@andreyvelich @johnugeorge @tenzen-y thanks for all the help

[johnugeorge]

Awesome work @deepanker13
/lgtm
/approve

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

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