Address review comments

Signed-off-by: Tushar Goel <[email protected]>

Author: TG1999

README.rst

@@ -59,6 +59,41 @@ Fetch some package metadata and get a ``fetchcode.packagedcode_models.Package``
     >>> list(package.info('pkg:rubygems/files'))
     [Package(type='rubygems', namespace=None, name='files', version=None)]
 
+Fetch a purl and get a ``fetchcode.fetch.Response`` object back::
+
+    >>> from fetchcode import fetch
+    >>> f = fetch('pkg:swift/github.com/Alamofire/[email protected]')
+    >>> f.location
+    '/tmp/tmp_cm02xsg'
+    >>> f.content_type
+    'application/zip'
+    >>> f.url
+    'https://github.com/Alamofire/Alamofire/archive/5.4.3.zip'
+
+Ecosystems supported for fetching a purl from fetchcode:
+
+  - alpm
+  - apk
+  - bitbucket
+  - cargo
+  - composer
+  - conda
+  - cpan
+  - cran
+  - deb
+  - gem
+  - generic
+  - github
+  - golang
+  - hackage
+  - hex
+  - luarocks
+  - maven
+  - npm
+  - nuget
+  - pub
+  - pypi
+  - swift
 
 License
 --------

src/fetchcode/__init__.py

@@ -134,9 +134,7 @@ def get_url_scheme(url):
     """
     Return the scheme of the given URL.
     """
-    url_parts = urlparse(url)
-    scheme = url_parts.scheme
-    return scheme
+    return urlparse(url).scheme
 
 
 def fetch(url):

src/fetchcode/composer.py

@@ -26,7 +26,6 @@ class Composer:
 
     @classmethod
     def get_download_url(cls, purl):
-
         """
         Return the download URL for a Composer PURL.
         """

tests/test_fetch.py

@@ -19,6 +19,8 @@
 import pytest
 
 from fetchcode import fetch
+from fetchcode import resolve_purl
+from fetchcode import resolve_url_from_purl
 
 
 @mock.patch("fetchcode.requests.get")
@@ -65,22 +67,121 @@ def test_fetch_with_scheme_not_present():
         assert "Not a supported/known scheme." == e_info
 
 
-@mock.patch("fetchcode.resolve_url_from_purl")
+@mock.patch("fetchcode._http_exists")
 @mock.patch("fetchcode.fetch_http")
-def test_fetch_purl(mock_fetch_http, mock_resolve):
+@mock.patch("fetchcode.pypi.fetch_json_response")
+def test_fetch_purl_with_fetchcode(mock_fetch_json_response, mock_fetch_http, mock_http_exists):
     mock_fetch_http.return_value = "mocked_purl_response"
-    mock_resolve.return_value = ("http://resolved.com/file.tar.gz", "http")
+    mock_http_exists.return_value = True
+    mock_fetch_json_response.return_value = {
+        "urls": [{"url": "https://example.com/sample-1.0.0.zip"}]
+    }
 
     response = fetch("pkg:pypi/[email protected]")
 
     assert response == "mocked_purl_response"
-    mock_resolve.assert_called_once()
+    mock_http_exists.assert_called_once()
+    mock_fetch_http.assert_called_once()
+
+
+@mock.patch("fetchcode._http_exists")
+@mock.patch("fetchcode.fetch_http")
+def test_fetch_purl_with_purl2url(mock_fetch_http, mock_http_exists):
+    mock_fetch_http.return_value = "mocked_purl_response"
+    mock_http_exists.return_value = True
+
+    response = fetch("pkg:alpm/[email protected]")
+
+    assert response == "mocked_purl_response"
+    mock_http_exists.assert_called_once()
     mock_fetch_http.assert_called_once()
 
 
-@mock.patch("fetchcode.get_url_scheme")
-def test_fetch_unsupported_scheme(mock_get_scheme):
-    mock_get_scheme.return_value = "s3"
+@mock.patch("fetchcode.pypi.fetch_json_response")
+def test_fetch_invalid_purl(mock_fetch_json_response):
+    mock_fetch_json_response.return_value = {}
 
+    with pytest.raises(Exception, match="No download URL found for invalid-package version 1.0.0"):
+        fetch("pkg:pypi/[email protected]")
+
+
+@mock.patch("fetchcode.pypi.fetch_json_response")
+def test_fetch_invalid_purl(mock_fetch_json_response):
+    mock_fetch_json_response.return_value = {}
+
+    with pytest.raises(Exception, match="No download URL found for invalid-package version 1.0.0"):
+        fetch("pkg:pypi/[email protected]")
+
+
+def test_fetch_unsupported_scheme():
     with pytest.raises(Exception, match="Not a supported/known scheme"):
         fetch("s3://bucket/object")
+
+
+def test_resolve_url_from_purl_invalid():
+    with pytest.raises(ValueError, match="Could not resolve PURL to a valid URL."):
+        fetch("pkg:invalid/[email protected]")
+
+
+@mock.patch("fetchcode._http_exists")
+def test_resolve_url_from_purl_using_purl2url(mock_http_exists):
+    mock_http_exists.return_value = True
+
+    url, _ = resolve_url_from_purl("pkg:swift/github.com/Alamofire/[email protected]")
+    assert url == "https://github.com/Alamofire/Alamofire/archive/5.4.3.zip"
+    mock_http_exists.assert_called_once_with(
+        "https://github.com/Alamofire/Alamofire/archive/5.4.3.zip"
+    )
+
+
+@mock.patch("fetchcode._http_exists")
+@mock.patch("fetchcode.pypi.fetch_json_response")
+def test_resolve_url_from_purl_using_fetchcode(mock_fetch_json_response, mock_http_exists):
+    mock_http_exists.return_value = True
+    mock_fetch_json_response.return_value = {
+        "urls": [{"url": "https://example.com/sample-1.0.0.zip"}]
+    }
+
+    url, _ = resolve_url_from_purl("pkg:pypi/[email protected]")
+    assert url == "https://example.com/sample-1.0.0.zip"
+    mock_http_exists.assert_called_once_with("https://example.com/sample-1.0.0.zip")
+
+
+def test_resolve_purl_invalid():
+    assert resolve_purl("pkg:invalid/[email protected]") is None
+
+
+def test_resolve_purl_using_purl2url():
+    url = resolve_purl("pkg:pub/[email protected]")
+    assert url == "https://pub.dev/api/archives/http-0.13.3.tar.gz"
+
+
+@mock.patch("fetchcode._http_exists")
+def test_resolve_purl_using_purl2url_url_does_not_exists(mock_http_exists):
+    mock_http_exists.return_value = False
+    url = resolve_purl("pkg:pub/[email protected]")
+    assert url is None
+
+
+@mock.patch("fetchcode._http_exists")
+@mock.patch("fetchcode.pypi.fetch_json_response")
+def test_resolve_purl_using_fetchcode(mock_fetch_json_response, mock_http_exists):
+    mock_fetch_json_response.return_value = {
+        "urls": [{"url": "https://example.com/sample-1.0.0.zip"}]
+    }
+    mock_http_exists.return_value = True
+    url = resolve_purl("pkg:pypi/[email protected]")
+    assert url == "https://example.com/sample-1.0.0.zip"
+
+
+@mock.patch("fetchcode._http_exists")
+@mock.patch("fetchcode.pypi.fetch_json_response")
+def test_resolve_purl_using_fetchcode_url_does_not_exists(
+    mock_fetch_json_response, mock_http_exists
+):
+    mock_fetch_json_response.return_value = {
+        "urls": [{"url": "https://example.com/sample-1.0.0.zip"}]
+    }
+    mock_http_exists.return_value = False
+    url = resolve_purl("pkg:pypi/[email protected]")
+    assert url is None