.

rules/fetch_file.bzl

@@ -0,0 +1,22 @@
+# TODO implement sha256sum attribute + checksum verification
+
+def _fetch_file_impl(ctx):
+    out_file = ctx.actions.declare_file(ctx.attr.filename)
+    ctx.actions.run_shell(
+        outputs = [out_file],
+        command = "curl -Lso \"$1\" \"$2\"",
+        arguments = [out_file.path, ctx.attr.url],
+        execution_requirements = {
+            "requires-network": "1",
+        },
+        progress_message = "Downloading plugin %s" % ctx.attr.filename,
+    )
+    return [DefaultInfo(files = depset([out_file]))]
+
+fetch_file = rule(
+    implementation = _fetch_file_impl,
+    attrs = {
+        "url": attr.string(mandatory = True),
+        "filename": attr.string(mandatory = True),
+    },
+)