Reduce core requirements (#426)

Test what happens when taking out some of the requirements that are only
used in sources

Author: cthoyt

pyproject.toml

@@ -63,7 +63,6 @@ dependencies = [
     "pyyaml",
     "pandas",
     "requests",
-    "protmapper",
     "more_itertools",
     "more_click>=0.0.2",
     "humanize",
@@ -76,7 +75,6 @@ dependencies = [
     "ssslm>=0.0.13",
     "zenodo-client>=0.3.6",
     "class_resolver>=0.6.0",
-    "psycopg2-binary",
     "pydantic>=2.0",
     "curies>=0.10.17",
     "curies-processing>=0.1.2",
@@ -158,6 +156,15 @@ gilda = [
 gilda-slim = [
     "ssslm[gilda-slim]",
 ]
+sources = [
+    "pyobo[drugcentral,pid]",
+]
+drugcentral =[
+    "psycopg2-binary",
+]
+pid = [
+    "protmapper",
+]
 
 # See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#urls
 # and also https://packaging.python.org/en/latest/specifications/well-known-project-urls/

src/pyobo/sources/drugcentral.py

@@ -6,7 +6,6 @@
 from contextlib import closing
 
 import bioregistry
-import psycopg2
 from pydantic import ValidationError
 from tqdm.auto import tqdm
 
@@ -42,6 +41,8 @@ def iter_terms(self, force: bool = False) -> Iterable[Term]:
 
 def iter_terms() -> Iterable[Term]:
     """Iterate over DrugCentral terms."""
+    import psycopg2
+
     with closing(psycopg2.connect(**PARAMS)) as conn:
         with closing(conn.cursor()) as cur:
             cur.execute(

tox.ini

@@ -120,6 +120,8 @@ description = Run the pyroma tool to check the package friendliness of the proje
 
 [testenv:mypy]
 description = Run the mypy tool to check static typing on the project. Installs the package to make sure all type stubs get recognized.
+extras =
+    sources
 dependency_groups =
     typing
 commands =