[Feature] File I/O migration and reconstruction

[Xiangxu-0103]

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Motivation

The fileio module has been refactored in mmengine in #533.
The modification can be referred from mmdet #9709.

Modification

• file_client_args has been renamed to backend_args, and HardDiskBackend to LocalBackend

  previous:

  file_client_args = dict(backend='disk')

  now:

  backend_args = dict(backend='local')

• Usage:

  previous:

  >>> import mmengine.fileio as fileio
  >>> client = fileio.FileClient(backend='petrel')
  >>> client.get('s3://path/of/your/file')
  b'hello world'
  
  >>> file_client_args = dict(backend='petrel')
  >>> client = fileio.FileClient.infer_client(file_client_args=file_client_args)
  >>> client.get('s3://path/of/your/file')
  b'hello world'
  >>> client = fileio.FileClient.infer_client(uri='s3://path/of/your/file')
  >>> client.get('s3://path/of/your/file')
  b'hello world'

  now:

  >>> import mmengine.fileio as fileio
  >>> backend = fileio.get_file_backend(backend_args={'backend': 'petrel'})
  >>> backend.get('s3://path/of/your/file')
  b'hello world'
  
  >>> fileio.get('s3://path/of/your/file', backend_args={'backend': 'petrel'})
  b'hello world'
  >>> fileio.get('s3://path/of/your/file')  # set backend_args to None, and let the file I/O module automatically infer from prefix to data root.
  b'hello world'

BC-breaking (Optional)

Does the modification introduce changes that break the back-compatibility of the downstream repos?
If so, please describe how it breaks the compatibility and how the downstream projects should modify their code to keep compatibility with this PR.

Use cases (Optional)

If this PR introduces a new feature, it is better to list some use cases here, and update the documentation.

Checklist

1. Pre-commit or other linting tools are used to fix the potential lint issues.
2. The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
3. If the modification has potential influence on downstream projects, this PR should be tested with downstream projects.
4. The documentation has been modified accordingly, like docstring or example tutorials.

[codecov]

Codecov Report

Patch coverage: 32.33% and project coverage change: -0.18 ⚠️

Comparison is base (8cf1acb) 47.04% compared to head (5d55ddf) 46.86%.

❗ Current head 5d55ddf differs from pull request most recent head a884e49. Consider uploading reports for the commit a884e49 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           dev-1.x    #2319      +/-   ##
===========================================
- Coverage    47.04%   46.86%   -0.18%     
===========================================
  Files          262      264       +2     
  Lines        22040    22173     +133     
  Branches      3467     3482      +15     
===========================================
+ Hits         10368    10392      +24     
- Misses       11006    11118     +112     
+ Partials       666      663       -3     

Flag	Coverage Δ
unittests	46.86% <32.33%> (-0.18%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
mmdet3d/datasets/scannet_dataset.py	82.75% <ø> (ø)
mmdet3d/datasets/waymo_dataset.py	17.72% <ø> (ø)
...tion/functional/waymo_utils/prediction_to_waymo.py	0.00% <0.00%> (ø)
mmdet3d/evaluation/metrics/waymo_metric.py	8.11% <ø> (ø)
mmdet3d/models/voxel_encoders/voxel_encoder.py	38.28% <ø> (-0.48%)	⬇️
mmdet3d/utils/misc.py	2.12% <0.00%> (-0.20%)	⬇️
mmdet3d/models/losses/lovasz_loss.py	16.81% <16.81%> (ø)
mmdet3d/evaluation/metrics/kitti_metric.py	9.09% <33.33%> (ø)
mmdet3d/models/decode_heads/cylinder3d_head.py	36.84% <36.84%> (ø)
mmdet3d/evaluation/metrics/lyft_metric.py	17.50% <50.00%> (ø)
... and 10 more

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[JingweiZhang12]

Please add a link of the corresponding refactoring in mmengine in PR message.
Please add a PR description about the difference between the usage of backend_args and that of file_client_args if they have.

[ZCMax]

Please check the replace_ceph_backend in train.py / test.py

[Xiangxu-0103]

Please check the replace_ceph_backend in train.py / test.py

Have checked.