Add Synapse backup s3-integration

[javierdelapuente]

Applicable spec: ISD095

Overview

This PR creates a new integration with S3 with the goal of being able to create, list, restore
and delete backups. Those tasks will be done in future PRs. In this one the goal is
to create the integration with a simple test to check that the bucket exists when s3-integration
is integrated with Synapse. All this functionality will be refined in the next PRs.

Rationale

Backups will me stored in S3, so the integration is needed.

Juju Events Changes

on_credentials_changed and on_credentials_gone from the charms.data_platform_libs.v0.s3 library.

Module Changes

New module backup that will handle backup functionality and will use S3 credentials.

Library Changes

Added charms.data_platform_libs.v0.s3 library.

Checklist

• The charm style guide was applied
• The contributing guide was applied
• The changes are compliant with ISD054 - Manging Charm Complexity
• The documentation is generated using src-docs
• The documentation for charmhub is updated.
• The PR is tagged with appropriate label (urgent, trivial, complex)

[cbartz]

Looks good overall, left some comments.

[amandahla]

LGTM

[github-actions]

Test coverage for ccd2406

Name                            Stmts   Miss Branch BrPart  Cover   Missing
---------------------------------------------------------------------------
src/actions/__init__.py             3      0      0      0   100%
src/actions/register_user.py       22      0      2      0   100%
src/actions/reset_instance.py      21      0      2      0   100%
src/backup.py                      37      0      2      0   100%
src/backup_observer.py             29      0      2      0   100%
src/charm.py                      222      8     50      4    96%   165-166, 227-228, 247-248, 289, 303
src/charm_state.py                 63      1     10      1    97%   127
src/charm_types.py                 21      0      2      0   100%
src/database_client.py             53      1     10      3    94%   35, 47->exit, 69->exit
src/database_observer.py           48      4      4      0    92%   69-71, 87
src/exceptions.py                   4      1      0      0    75%   22
src/mjolnir.py                     76      6     20      1    91%   60-64, 73
src/observability.py                9      0      0      0   100%
src/pebble.py                      96     12     16      6    84%   91-92, 94-95, 103, 105, 107, 111, 132-133, 148-149
src/saml_observer.py               45      1      8      0    98%   64
src/smtp_observer.py               70      3     14      1    95%   70-74, 96->101
src/synapse/__init__.py             3      0      0      0   100%
src/synapse/api.py                161      2     22      2    98%   207, 376
src/synapse/workload.py           261      8     42      6    95%   386->exit, 415-416, 468-469, 505-506, 522, 571->574, 618, 626->628, 628->630
src/user.py                        24      0      4      0   100%
---------------------------------------------------------------------------
TOTAL                            1268     47    210     24    95%

Static code analysis report

Run started:2024-01-22 13:48:49.532394

Test results:
  No issues identified.

Code scanned:
  Total lines of code: 6802
  Total lines skipped (#nosec): 4
  Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 0

Run metrics:
  Total issues (by severity):
  	Undefined: 0
  	Low: 0
  	Medium: 0
  	High: 0
  Total issues (by confidence):
  	Undefined: 0
  	Low: 0
  	Medium: 0
  	High: 0
Files skipped (0):