Enterprise: Difference between revisions

@@ Line 40: / Line 40: @@
 The proxy itself can be set via the environment variables <code>HTTP_PROXY</code> and <code>HTTPS_PROXY</code>.
+== Dynamic generation of netrc files ==
+Sometimes you have to deal with dynamically short-lived tokens that must be generated on the fly. The above options do not cover this, so the best way forward is to use `fetchurl`'s `netrcPhase` option:
+ newPkgs = pkgs.extend (
+    final: prev: {
+      fetchurl =
+        args:
+        (prev.fetchurl.override {
+          inherit (pkgs) cacert; # required to avoid infrec
+        })
+          (
+            args
+            // {
+              netrcPhase =
+                # do stuff here to get credentials
+                BAR=\'\'$(dynamic-shell-script)
+                cat > netrc <<EOF
+                machine foobar
+                        login FOO
+                        password \'\'$BAR
+                EOF
+              '';''
+            }
+          );
+    }
+  );
+now any fetch in newPkgs will dynamically generate tokens with `fetchurl`.
 [[Category:Networking]]