feat: support private key env.

[ya7010]

After updating from 3.7.0 to 4.0.1, authentication by keypath now gives an error.

This PR restores the implementation that recognizes SNOWFLAKE_PRIVATE_KEY_PATH, SNOWFLAKE_PRIVATE_KEY_PASSPHRASE.

The GitHub Action workflow we used is as follows:

jobs:
  schemachange:
      - ...
      - name: Execute Snowflake migration
        env:
          SNOWFLAKE_ACCOUNT: ${{ secrets.SNOWFLAKE_ACCOUNT }}
          SNOWFLAKE_PRIVATE_KEY_PATH: ${{ secrets.SNOWFLAKE_PRIVATE_KEY_PATH }}
          SNOWFLAKE_PRIVATE_KEY_PASSPHRASE: ${{ secrets.SCHEMA_CHANGE_SNOWFLAKE_PRIVATE_KEY_PASSPHRASE }}
        run: |
          echo "${{ secrets.SCHEMA_CHANGE_SNOWFLAKE_PRIVATE_KEY }}" > ${{ env.SNOWFLAKE_PRIVATE_KEY_PATH }}
          schemachange -a $SNOWFLAKE_ACCOUNT
          rm -f ${{ env.SNOWFLAKE_PRIVATE_KEY_PATH }}

Since Snowflake is discontinuing single-factor password authentication, my team has moved to Key/Pair authentication.

[AttilaVM]

This statement should not be removed even after connections.toml is enforced. Since, we will not want to write the private key passphrase into a file even then.

[ya7010]

cd20507

Fixed to use private_key_path, and removed comments.

[ya7010]

@AttilaVM

My team is waiting for PASSPHRASE support to be released.

Is there anything else I can do?

[mibelbahri]

@ya7010 shouldn't we go all the way to just supporting SNOWFLAKE_PRIVATE_KEY as an env variable instead of SNOWFLAKE_PRIVATE_KEY_PATH (avoiding materializing the key all together)

[ya7010]

@mibelbahri
Are you referring to using SNOWFLAKE_PRIVATE_KEY instead of SNOWFLAKE_PRIVATE_KEY_PATH?

I think SNOWFLAKE_PRIVATE_KEY_PASSPHRASE should be retained.

[ya7010]

@sfc-gh-tmathew

Is there anything I can do to help merge this PR?