Preserve npm scopes when fetching package metadata

Signed-off-by: Ali Zulfiqar <codewithfourtix@gmail.com>

Author: codewithfourtix

src/fetchcode/package.py

@@ -122,7 +122,8 @@ def get_npm_data_from_purl(purl):
     base_path = "http://registry.npmjs.org"
     name = purl.name
     version = purl.version
-    api_url = f"{base_path}/{name}"
+    full_name = f"{purl.namespace}/{name}" if purl.namespace else name
+    api_url = f"{base_path}/{full_name}"
 
     response = get_response(api_url)
     vcs_data = response.get("repository") or {}
@@ -136,7 +137,9 @@ def get_npm_data_from_purl(purl):
     versions = response.get("versions", [])
     for num in versions:
         version = versions[num]
-        version_purl = PackageURL(type=purl.type, name=name, version=version.get("version"))
+        version_purl = PackageURL(
+            type=purl.type, namespace=purl.namespace, name=name, version=version.get("version")
+        )
         repository = version.get("repository") or {}
         bugs = response.get("bugs") or {}
         dist = version.get("dist") or {}

tests/test_npm_metadata_scope.py

@@ -0,0 +1,36 @@
+# fetchcode is a free software tool from nexB Inc. and others.
+# Visit https://github.com/aboutcode-org/fetchcode for support and download.
+
+# Copyright (c) nexB Inc. and others. All rights reserved.
+# http://nexb.com and http://aboutcode.org
+
+# This software is licensed under the Apache License version 2.0.
+
+# You may not use this software except in compliance with the License.
+# You may obtain a copy of the License at:
+# http://apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software distributed
+# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations under the License.
+
+import pytest
+
+from fetchcode import package
+
+
+@pytest.mark.parametrize(
+    "purl,registry_name",
+    [("pkg:npm/%40scope/example@1.0", "@scope/example"), ("pkg:npm/example@1.0", "example")],
+)
+def test_npm_metadata_preserves_scope(monkeypatch, purl, registry_name):
+    urls = []
+
+    def response(url):
+        urls.append(url)
+        return {"versions": {"1.0": {"version": "1.0"}}}
+
+    monkeypatch.setattr(package, "get_response", response)
+    result = list(package.get_npm_data_from_purl(purl))
+    assert urls == ["http://registry.npmjs.org/" + registry_name]
+    assert result[0].purl == purl