Add SQLFluff /format endpoint to the server

[barrywhart]

How to use it:

# Launch the server
python src/dbt_core_interface/project.py

# Register the dbt project with the server (one-time only). Providing absolute file
# paths to the project and profile directory is best.
curl -X POST \
     -H "Content-Type: application/json" \
     -H "X-dbt-Project: dbt_project" \
     -d '{
       "project_dir": "/Users/barry/dev/dbt-core-interface/tests/sqlfluff_templater/fixtures/dbt/dbt_project",
       "profiles_dir": "/Users/barry/dev/dbt-core-interface/tests/sqlfluff_templater/fixtures/dbt/profiles_yml",
       "target": "dev"
     }' \
     http://localhost:8581/register

# Format the file. Providing an absolute file path is best.
curl -X POST \
     -H "Content-Type: application/json" \
     -H "X-dbt-Project: dbt_project" \
     "http://localhost:8581/format?sql_path=/Users/barry/dev/dbt-core-interface/tests/sqlfluff_templater/fixtures/dbt/dbt_project/models/my_new_project/issue_1608.sql"

[BAntonellini]

@barrywhart I can't make /format work, it says local variable 'res' referenced before assignment, any clue?

[barrywhart]

@BAntonellini: I see the issue. I have this code:

        num_fixable = lint_result.num_violations(types=SQLLintError, fixable=True)
        if num_fixable > 0:
            res = lint_result.persist_changes(
                formatter=formatter, fixed_file_suffix=""
            )
        success = all(res.values())

The success = line accesses res, but if num_fixable is 0, the variable is undefined. Easy fix -- I'll push that later today.

[barrywhart]

@BAntonellini: I fixed the bug. The behavior you saw would occur if the "format" endpoint found there were no changes to be made (or more precisely, no automated changes).