feat: display src file location next to the version for each derivation

Author: erictapen

src/website/shared/listeners/cache_suggestions.py

@@ -1,5 +1,6 @@
 import logging
 import re
+import urllib.parse
 from itertools import chain
 from typing import Any
 
@@ -179,6 +180,24 @@ def is_version_affected(version_statuses: list[str]) -> Version.Status:
     return result
 
 
+def get_src_position(derivation: NixDerivation) -> str | None:
+    """
+    Get the GitHub URL pointing to the exact source file used for the evaluation of this derivation.
+    E.g. https://github.com/NixOS/nixpkgs/blob/0e8be3827d0298743ba71b91eea652d43d7dc03d/pkgs/by-name/he/hello/package.nix#L47
+    """
+    if derivation.metadata and derivation.metadata.position:
+        rev = urllib.parse.quote(derivation.parent_evaluation.commit_sha1)
+        # position is something like `/tmp/tmpfh7ff2xs/pkgs/development/python-modules/qemu/default.nix:67`
+        position_match = re.match(
+            r"/tmp/[^/]+/(.+):(\d+)", derivation.metadata.position
+        )
+        if position_match:
+            path = urllib.parse.quote(position_match.group(1))
+            linenumber = urllib.parse.quote(position_match.group(2))
+            return f"https://github.com/NixOS/nixpkgs/blob/{rev}/{path}#L{linenumber}"
+    return None
+
+
 def channel_structure(
     version_constraints: list[Version], derivations: list[NixDerivation]
 ) -> dict:
@@ -211,21 +230,26 @@ def channel_structure(
                     "major_version": None,
                     "status": None,
                     "uniform_versions": None,
+                    "src_position": None,
                     "sub_branches": dict(),
                 }
-            if not branch_name == major_channel:
+            if branch_name == major_channel:
+                packages[attribute]["versions"][major_channel]["major_version"] = (
+                    version
+                )
+                packages[attribute]["versions"][major_channel]["src_position"] = (
+                    get_src_position(derivation)
+                )
+            else:
                 packages[attribute]["versions"][major_channel]["sub_branches"][
                     branch_name
                 ] = {
                     "version": version,
                     "status": is_version_affected(
                         [v.is_affected(version) for v in version_constraints]
                     ),
+                    "src_position": get_src_position(derivation),
                 }
-            else:
-                packages[attribute]["versions"][major_channel]["major_version"] = (
-                    version
-                )
     for package_name in packages:
         for mc in packages[package_name]["versions"].keys():
             uniform_versions = True

src/website/webview/static/style.css

@@ -764,6 +764,12 @@ article .nixpkgs-packages {
   min-width: 5em;
   display: inline-block;
   text-align: end;
+  text-decoration: none;
+  color: black;
+}
+
+.nixpkgs-package .version:hover {
+  text-decoration: underline;
 }
 
 .nixpkgs-package .version.affected {

src/website/webview/templates/components/nixpkgs_package.html

@@ -7,26 +7,31 @@ <h3><span class="pkgs">pkgs.</span>{{ attribute_name }}</h3>
       {{ pdata.description }}
     </div>
     <ul class="channel-list">
-      {% for major_channel, val in pdata.versions %}
+      {% for major_channel, major_version in pdata.versions %}
         <li>
-          <details {% if val.uniform_versions %}open{% endif %}>
+          <details {% if major_version.uniform_versions %}open{% endif %}>
             <summary>
               <span class="branch-major">
                 <span class="branch-name">{{ major_channel }}</span>
-                <span class="version {{ val.status }}">
-                  {% if val.major_version %}
-                    {{ val.major_version }}
+                <a class="version {{ major_version.status }}" target="_blank" href="{{ major_version.src_position }}">
+                  {% if major_version.major_version %}
+                    {{ major_version.major_version }}
                   {% else %}
                     ???
                   {% endif %}
-                </span>
+                </a>
               </span>
             </summary>
             <ul class="channel-list">
-            {% for branch_name, vdata in val.sub_branches %}
+            {% for branch_name, minor_version in major_version.sub_branches %}
               <li class="branch-minor">
                 <span class="branch-name">{{ branch_name }}</span>
-                <span class="version {{ vdata.status }}">{{ vdata.version }}</span>
+                <a
+                  class="version {{ minor_version.status }}"
+                  target="_blank"
+                  href="{{ minor_version.src_position }}">
+                    {{ minor_version.version }}
+                </a>
               </li>
             {% endfor %}
             </ul>