fix: Use base.in for install_requires (#779)

setup.py

@@ -2,12 +2,131 @@
 
 import io
 import os
+import re
 
 from setuptools import find_packages, setup
 
 HERE = os.path.abspath(os.path.dirname(__file__))
 
 
+class MultipleConstraintException(BaseException):
+    """
+    Exception raised when multiple constraints are provided.
+    """
+
+
+def load_requirements(*requirements_paths):
+    """
+    Load all requirements from the specified requirements files.
+
+    Requirements will include any constraints from files specified
+    with -c in the requirements files.
+    Returns a list of requirement strings.
+    """
+    # Removed the automated comment that was because it fails linting
+    # similarly had to update other code below for lint fails.
+
+    # e.g. {"django": "Django", "confluent-kafka": "confluent_kafka[avro]"}
+    by_canonical_name = {}
+
+    def check_name_consistent(package):
+        """
+        Raise exception if package is named different ways.
+
+        This ensures that packages are named consistently so we can match
+        constraints to packages. It also ensures that if we require a package
+        with extras we don't constrain it without mentioning the extras (since
+        that too would interfere with matching constraints.)
+        """
+        canonical = package.lower().replace("_", "-").split("[")[0]
+        seen_spelling = by_canonical_name.get(canonical)
+        if seen_spelling is None:
+            by_canonical_name[canonical] = package
+        elif seen_spelling != package:
+            raise Exception(  # pylint: disable=broad-exception-raised
+                f'Encountered both "{seen_spelling}" and "{package}" in requirements '
+                "and constraints files; please use just one or the other."
+            )
+
+    requirements = {}
+    constraint_files = set()
+
+    # groups "pkg<=x.y.z,..." into ("pkg", "<=x.y.z,...")
+    re_package_name_base_chars = r"a-zA-Z0-9\-_."  # chars allowed in base package name
+    # Two groups: name[maybe,extras], and optionally a constraint
+    requirement_line_regex = re.compile(
+        r"([%s]+(?:\[[%s,\s]+\])?)([<>=][^#\s]+)?"  # pylint: disable=consider-using-f-string
+        % (re_package_name_base_chars, re_package_name_base_chars)
+    )
+
+    def add_version_constraint_or_raise(
+        current_line, current_requirements, add_if_not_present
+    ):
+        regex_match = requirement_line_regex.match(current_line)
+        if regex_match:
+            package = regex_match.group(1)
+            version_constraints = regex_match.group(2)
+            check_name_consistent(package)
+            existing_version_constraints = current_requirements.get(package, None)
+            # It's fine to add constraints to an unconstrained package,
+            # but raise an error if there are already constraints in place.
+            if (
+                existing_version_constraints
+                and existing_version_constraints != version_constraints
+            ):
+                raise MultipleConstraintException(
+                    f"Multiple constraint definitions found for {package}:"
+                    f' "{existing_version_constraints}" and "{version_constraints}".'
+                    f"Combine constraints into one location with {package}"
+                    f"{existing_version_constraints},{version_constraints}."
+                )
+            if add_if_not_present or package in current_requirements:
+                current_requirements[package] = version_constraints
+
+    # Read requirements from .in files and store the path to any
+    # constraint files that are pulled in.
+    for path in requirements_paths:
+        with open(path, encoding="utf8") as reqs:
+            for line in reqs:
+                if is_requirement(line):
+                    add_version_constraint_or_raise(line, requirements, True)
+                if line and line.startswith("-c") and not line.startswith("-c http"):
+                    constraint_files.add(
+                        os.path.dirname(path)
+                        + "/"
+                        + line.split("#")[0].replace("-c", "").strip()
+                    )
+
+    # process constraint files: add constraints to existing requirements
+    for constraint_file in constraint_files:
+        with open(constraint_file, encoding="utf8") as reader:
+            for line in reader:
+                if is_requirement(line):
+                    add_version_constraint_or_raise(line, requirements, False)
+
+    # process back into list of pkg><=constraints strings
+    constrained_requirements = [
+        f'{pkg}{version or ""}' for (pkg, version) in sorted(requirements.items())
+    ]
+    return constrained_requirements
+
+
+def is_requirement(line):
+    """
+    Return True if the requirement line is a package requirement.
+
+    Returns:
+        bool: True if the line is not blank, a comment,
+        a URL, or an included file
+    """
+    # Removed the automated comment that was because it fails linting
+    # similarly had to update other code below for lint fails.
+
+    return (
+        line and line.strip() and not line.startswith(("-r", "#", "-e", "git+", "-c"))
+    )
+
+
 def load_readme():
     """Load README file which populates long_description field."""
     with io.open(os.path.join(HERE, "README.rst"), "rt", encoding="utf8") as file:
@@ -45,7 +164,7 @@ def load_about():
     packages=find_packages(exclude=["tests*"]),
     include_package_data=True,
     python_requires=">=3.7",
-    install_requires=["tutor", "bcrypt"],
+    install_requires=load_requirements("requirements/base.in"),
     entry_points={"tutor.plugin.v1": ["aspects = tutoraspects.plugin"]},
     classifiers=[
         "Development Status :: 3 - Alpha",