Replace requests with httpx for unified HTTP client (Phase 4)

- bcb/sgs/__init__.py: replace requests.get with httpx.get
- bcb/currency.py: replace all requests.get calls with httpx.get,
  update _get_valid_currency_list return type to httpx.Response,
  replace requests.exceptions.ConnectionError with httpx.ConnectError
- Add follow_redirects=True to all httpx.get calls (requests follows
  redirects by default; httpx does not)
- pyproject.toml: remove requests from main dependencies; remove
  types-requests from dev dependencies (no longer needed)

poetry run mypy bcb/ exits clean; all 19 tests pass.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: wilsonfreitas

bcb/currency.py

@@ -4,9 +4,9 @@
 from io import BytesIO, StringIO
 from typing import List, Optional, Union
 
+import httpx
 import numpy as np
 import pandas as pd
-import requests
 from lxml import html
 
 from .exceptions import BCBAPIError, CurrencyNotFoundError
@@ -35,7 +35,7 @@ def _currency_id_list() -> pd.DataFrame:
         return CACHE.get("TEMP_CURRENCY_ID_LIST")
     else:
         url1 = "https://ptax.bcb.gov.br/ptax_internet/consultaBoletim.do?" "method=exibeFormularioConsultaBoletim"
-        res = requests.get(url1)
+        res = httpx.get(url1, follow_redirects=True)
         if res.status_code != 200:
             msg = f"BCB API Request error, status code = {res.status_code}"
             raise BCBAPIError(msg, res.status_code)
@@ -49,11 +49,11 @@ def _currency_id_list() -> pd.DataFrame:
         return df
 
 
-def _get_valid_currency_list(_date: date, n: int = 0) -> requests.models.Response:
+def _get_valid_currency_list(_date: date, n: int = 0) -> httpx.Response:
     url2 = f"http://www4.bcb.gov.br/Download/fechamento/M{_date:%Y%m%d}.csv"
     try:
-        res = requests.get(url2)
-    except requests.exceptions.ConnectionError as ex:
+        res = httpx.get(url2, follow_redirects=True)
+    except httpx.ConnectError as ex:
         if n >= 3:
             raise ex
         return _get_valid_currency_list(_date, n + 1)
@@ -112,7 +112,7 @@ def _get_symbol(symbol: str, start_date: DateInput, end_date: DateInput) -> Opti
     except CurrencyNotFoundError:
         return None
     url = _currency_url(cid, start_date, end_date)
-    res = requests.get(url)
+    res = httpx.get(url, follow_redirects=True)
 
     if res.headers["Content-Type"].startswith("text/html"):
         doc = html.parse(BytesIO(res.content)).getroot()

bcb/sgs/__init__.py

@@ -2,8 +2,8 @@
 from io import StringIO
 from typing import Dict, Generator, List, Mapping, Optional, Tuple, TypeAlias, Union
 
+import httpx
 import pandas as pd
-import requests
 
 from bcb.exceptions import SGSError
 from bcb.utils import Date, DateInput
@@ -187,7 +187,7 @@ def get_json(
         série temporal univariada em formato JSON.
     """
     url, payload = _get_url_and_payload(code, start, end, last)
-    res = requests.get(url, params=payload)
+    res = httpx.get(url, params=payload, follow_redirects=True)
     if res.status_code != 200:
         try:
             res_json = json.loads(res.text)

poetry.lock

@@ -11,7 +11,6 @@ python = ">= 3.10"
 httpx = ">= 0.24.0"
 lxml = ">= 4.9.2"
 pandas = ">= 2.0.0"
-requests = ">= 2.31.0"
 
 [tool.poetry.group.test.dependencies]
 pytest = ">= 7.1.3"
@@ -34,7 +33,6 @@ black = { version = ">= 22.8.0", allow-prereleases = true }
 jupyter = "^1.1.1"
 mypy = ">= 1.0.0"
 pytest-cov = ">= 4.0.0"
-types-requests = "^2.32.4.20260107"
 
 [build-system]
 requires = ["poetry-core"]