The API contract is being broken. The field inicio_operacao was previously guaranteed to return a date string, and now it returns null for all participants. This is a breaking change that affects all API consumers expecting this field.

According to the documentation update, BCB stopped providing this data in November 2025, but the solution should maintain backward compatibility. Consider one of these approaches:

1. Create a new API version (v2) with the updated structure
2. Keep trying to parse the field when available instead of hardcoding null
3. Clearly document this as a breaking change and coordinate with stakeholders

This violates the fundamental principle: "SEMPRE mantenha compatibilidade retroativa em endpoints existentes".

The data mapping appears incorrect. The code defines only 4 expected headers but then accesses array indices beyond those headers (data[6], data[8]).

The expectedHeaders array has:

• Index 0: 'nomereduzido'
• Index 1: 'ispb'
• Index 2: 'modalidadedeparticipaçãonopix'
• Index 3: 'tipodeparticipaçãonospi'

But the mapping uses data[2], data[1], data[6], data[8], which suggests the actual CSV has more columns than what's being validated. Either:

1. Update expectedHeaders to include all columns in the CSV, or
2. Adjust the mapping indices to match the 4 validated headers

This mismatch will cause incorrect data to be returned or potential runtime errors.

The field nome_reduzido is being set to the same value as nome (both use data[1]). This appears to be incorrect since these fields should represent different data (full name vs. short name).

According to the expectedHeaders, 'nomereduzido' is the first column (index 0 after splitting). The mapping should likely be:

• nome_reduzido: data[0] (nomereduzido)
• ispb: data[1] (ispb)

Please verify the actual CSV structure and map the fields correctly.

The filter filter(([ispb]) => ispb) is filtering by the first element of each row (index 0), but according to the header mapping, ISPB is at index 1, not index 0. This means the filter is checking the wrong column.

This should be updated to match the actual column position of ISPB in the CSV, or if filtering by the first column is intentional, the logic should be documented and verified against the actual CSV structure.

De fato ele tem razão @RodriAndreotti , ou a gnt ta viajando?

The weekend handling logic has a subtle issue. When checking today.getDay() === 0 (Sunday), it tries to fetch data from 2 days before. However, the actual parameter is not being passed to obtainPixParticipantList, so on line 20 the fallback logic will call getPixParticipants(false) which defaults to daysBefore = 1. This means if there's a 404 on Sunday for the 2-days-ago file, the fallback will only go back 1 day (Saturday) instead of trying other dates. Consider passing the appropriate daysBefore value to the fallback as well.

The daysBefore parameter was added but it's not clear what its purpose is just from the signature. Consider adding JSDoc documentation to explain when and why this parameter should be used, especially since it's part of the weekend handling logic introduced in this PR.

The isEqual function has been changed to check if required headers are present in the headers array, but this is less strict than the original implementation. The original checked for exact equality (same order and length), while the new version only checks if the required headers exist somewhere in the array. This means the function will pass even if there are extra columns or if columns are in a different order. However, the data mapping on lines 78-83 relies on specific column indices, so if columns are reordered, the data will be mapped incorrectly. The validation should ensure the headers match exactly in order and position.