feat: support max_upload_dir_size config

[Narayanbhat166]

Description

This Pull Request adds a feature to limit the uploads if the ./uploads dir is full. The size of ./uploads dir can be set by the config key max_upload_dir_size under the server config.

[server]
max_upload_dir_size = "100G"

Motivation and Context

This is required to restrict the number / size of uploads that can be made to the server when hosted publicly.
This fixes #282

How Has This Been Tested?

Changelog Entry

• Add a check for the max size of uploads directory

Types of Changes

• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the code style of this project.
• I have updated the documentation accordingly.
• I have formatted the code with rustfmt.
• I checked the lints with clippy.
• I have added tests to cover my changes.
• All new and existing tests passed.

[orhun]

Thanks! Had some comments:

[orhun]

Let's get this over the finish line soon if possible :)

[orhun]

Ping :)

[tessus]

@Narayanbhat166 can you have a look and make the requested changes?

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 6.66667% with 28 lines in your changes missing coverage. Please review.

Project coverage is 80.51%. Comparing base (1d5a9c6) to head (aad5f77).
Report is 29 commits behind head on master.

Files with missing lines	Patch %	Lines
src/util.rs	0.00%	17 Missing ⚠️
src/paste.rs	15.38%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #335      +/-   ##
==========================================
- Coverage   83.27%   80.51%   -2.76%     
==========================================
  Files          11       11              
  Lines        1214     1273      +59     
==========================================
+ Hits         1011     1025      +14     
- Misses        203      248      +45     

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[tessus]

@orhun I was just wondering what kind of perf impact this has. Isn't this similar to the duplicates=false issue? Every time there is an upload, all files have to be touched. Yes, getting the size of all files is probably a lot faster than calculating the hash for each file, but still. Patterns like this make me nervous, coming from a perf background.

[orhun]

Yeah, probably the performance will be degrade in a noticeable way with this feature enabled.

I think we need to add benchmarks using hyperfine to get an idea about that. I did something similar for Zig in https://github.com/orhun/zig-http-benchmarks