# Backend internal interview (rust)
## CHANGES: fixed branch
- Moving from **HashMap** to **BTreeMap** to preseve loading lines order.
- Fix **lines parser** in Maps **metrics** and in **aggregated_metrics** to be handled properly.
- Fix **unwrap / expect** for obvious reasons, add simple error message via **map_err**, **unwrap_or_else** and **closure function**.
- Fix some source code lines order, output format and conversions.
- Change some **iterators** to functional mode.
- Separate tasks to independent funtions for better isolation, less responsibilities and help on **tests** handling.
- Adding **output_path** to help on result output options.
- Following **unit tests** are implemented:
- test_load_input test load input file **input.txt**.
- test_invalid_line_value test use invalid value in line parsing.
- test_invalid_line test use invlid value in line parsing.
- test_expected_metrics test load input data from **input.txt** compare with **output_expected.txt**.
> Code simply **works as expected**
> It is not be able to **process multiple metrics in parallel** yet.
> A full refactoring has to be done for better quality, maintenance and be more readable. (Structs, implementaitions, settings for multiple inputs, etc).
Next round in: [Improve branch](/NewRelic/be-technical-interview-rust/src/branch/improved)