From 2d7d9db257223075074aef249b13b7acb47bcf75 Mon Sep 17 00:00:00 2001
From: Reid 'arrdem' McKenzie <me@arrdem.com>
Date: Sat, 25 Sep 2021 01:12:47 -0600
Subject: [PATCH] Disable sandboxing so Zapp! can cache rebuilt wheels

---
 zapp/compiler/__main__.py | 31 +++++++++++++++++++++----------
 zapp/zapp.bzl             |  3 +++
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/zapp/compiler/__main__.py b/zapp/compiler/__main__.py
index eaeea24..0ae5661 100644
--- a/zapp/compiler/__main__.py
+++ b/zapp/compiler/__main__.py
@@ -13,6 +13,8 @@ import zipfile
 from collections import defaultdict
 from email.parser import Parser
 from itertools import chain
+from pathlib import Path
+from pprint import pprint
 from shutil import move
 from tempfile import TemporaryDirectory
 
@@ -148,13 +150,26 @@ def wheel_name(wheel):
 def zip_wheel(tmpdir, wheel):
     """Build a 'tempfile' containing the proper contents of the wheel."""
 
-    wheel_file = os.path.join(tmpdir, wheel_name(wheel))
+    wn = wheel_name(wheel)
+    cached_path = cache_wheel_path(wn)
+    wheel_file = os.path.join(tmpdir, wn)
 
     with zipfile.ZipFile(wheel_file, "w") as whl:
         for dest, src in wheel["sources"]:
             whl.write(src["source"], dest)
 
-    return wheel_file
+    try:
+        # Attempt to enter the (re)built wheel into the cache. This could fail
+        # due to coss-device rename problems, or due to something else having
+        # concurrently built the same wheel and won the race.
+        #
+        # FIXME: This probably needs some guardrails to ensure that we only put
+        # architecture-independent wheels into the cache this way to avoid the
+        # plethora of "missbehaved wheels" problems that pip deals with.
+        Path(wheel_file).rename(cached_path)
+        return str(cached_path)
+    except OSError:
+        return wheel_file
 
 
 def rezip_wheels(opts, manifest):
@@ -177,12 +192,6 @@ def rezip_wheels(opts, manifest):
         # Expunge sources available in the wheel
         manifest["sources"] = dsub(manifest["sources"], w["sources"])
 
-        if opts.debug:
-            from pprint import pprint
-
-            print("---")
-            pprint({"$type": "whl", **w})
-
         # We may have a double-path dependency.
         # If we DON'T, we have to zip
         if wn not in manifest["wheels"]:
@@ -194,6 +203,10 @@ def rezip_wheels(opts, manifest):
                     pass
                 wf = str(wf)
             else:
+                if opts.debug:
+                    print("---")
+                    pprint({"$type": "whl", **w})
+
                 wf = zip_wheel(opts.tmpdir, w)
 
             # Insert a new wheel source
@@ -293,8 +306,6 @@ def main():
         manifest = insert_manifest_json(opts, manifest)
 
         if opts.debug:
-            from pprint import pprint
-
             print("---")
             pprint(
                 {
diff --git a/zapp/zapp.bzl b/zapp/zapp.bzl
index de8c99d..5c35e74 100644
--- a/zapp/zapp.bzl
+++ b/zapp/zapp.bzl
@@ -160,6 +160,9 @@ def _zapp_impl(ctx):
         ],
         mnemonic = "PythonCompile",
         use_default_shell_env = True,
+        execution_requirements = {
+            "no-sandbox": "",  # So zappc can use a filesystem cache of (re)build wheels
+        },
     )
 
     # .zapp file itself has no runfiles and no providers