Add support for converting pyproject.toml-based Python3 packages.

Fixes jordansissel#1780
Fixes jordansissel#1873
Fixes jordansissel#1860
Fixes magma/magma#13847

lib/fpm/package/pyfpm_wheel/__init__.py

@@ -0,0 +1 @@
+__all__ = [ "get_metadata_wheel" ]

lib/fpm/package/pyfpm_wheel/get_metadata_wheel.py

@@ -0,0 +1,98 @@
+import os
+import sys
+import pkg_resources
+from pkginfo import Wheel
+import traceback
+
+import json
+
+# If you have fixes, let me know.
+
+class get_metadata_wheel:
+    wheel_path = None
+
+    def __init__(self, wheel_path):
+        self.wheel_path = wheel_path
+
+    def process_dep(self, dep):
+        deps = []
+        if hasattr(dep, 'marker') and dep.marker:
+            # PEP0508 marker present
+            if not dep.marker.evaluate():
+                return deps
+
+        if dep.specs:
+            for operator, version in dep.specs:
+                deps.append("%s %s %s" % (dep.project_name,
+                        operator, version))
+        else:
+            deps.append(dep.project_name)
+
+        return deps
+
+    def get_home_url(self, project_urls):
+        res = dict([i.strip() for i in x.split(',')] for x in project_urls)
+        return res.get('Home', None)
+
+    def run(self, output_path):
+
+        fpm_wheel = Wheel(self.wheel_path)
+        data = {
+            "name": fpm_wheel.name,
+            "version": fpm_wheel.version,
+            "description": fpm_wheel.summary,
+            "license": fpm_wheel.license,
+        }
+
+        if fpm_wheel.author:
+            data["author"] = "%s <%s>" % (fpm_wheel.author, fpm_wheel.author_email)
+        else:
+            data["author"] = "%s" % (fpm_wheel.author_email)
+
+        if fpm_wheel.home_page:
+            data["url"] =  fpm_wheel.home_page
+        else:
+            data["url"] =  self.get_home_url(fpm_wheel.project_urls)
+
+        # @todo FIXME!!!
+        if fpm_wheel.requires_external:
+            data["architecture"] = "native"
+        else:
+            data["architecture"] = "all"
+
+        print('REQ-TOML:', fpm_wheel.requires, file=sys.stderr)
+        print('REQ-TOML DIST:', fpm_wheel.requires_dist, file=sys.stderr)
+
+
+        final_deps = []
+
+        # @todo FIXME!!!
+
+        try:
+            if fpm_wheel.requires_dist:
+                for dep in pkg_resources.parse_requirements(fpm_wheel.requires_dist):
+                    final_deps.extend(self.process_dep(dep))
+
+    #        if fpm_wheel.requires_dist:
+    #            for dep in pkg_resources.parse_requirements(
+    #                    v for k, v in fpm_wheel.requires_dist
+    #                    if k.startswith(':') and pkg_resources.evaluate_marker(k[1:])):
+    #                final_deps.extend(self.process_dep(dep))
+        except Exception as e:
+            print('REQ-TOML-DEPS-EXCEPTION:', str(e), '\n', repr(traceback.format_exc()), file=sys.stderr)
+            raise
+
+
+        print('REQ-TOML-FINAL-DEPS:', final_deps, file=sys.stderr)
+        data["dependencies"] = final_deps
+
+        with open(output_path, "w") as output:
+            def default_to_str(obj):
+                """ Fall back to using __str__ if possible """
+                # This checks if the class of obj defines __str__ itself,
+                # so we don't fall back to an inherited __str__ method.
+                if "__str__" in type(obj).__dict__:
+                    return str(obj)
+                return json.JSONEncoder.default(self, obj)
+
+            output.write(json.dumps(data, indent=2, sort_keys=True, default=default_to_str))