Why Python 3.12 Triggers App Store Rejection and How CPython Is Fixing It

When Python applications are built with Python 3.12 and submitted to the macOS App Store, the review process may reject the binary. The rejection is triggered by the literal string itms-services that appears in the standard‑library module urllib/parse.py and its compiled .pyc files. Apple’s automated scanner looks for this string because the itms-services URL scheme is prohibited for sandboxed App Store apps under guideline 2.5.2 (Performance – Software Requirements).

Root Cause

Python 3.12 added support for parsing itms-services URLs in urllib.parse. The code contains a literal reference to the scheme, e.g.:

if scheme == "itms-services":
    # handle enterprise installation URL
    ...

Even if an application never invokes this code path, the presence of the string in the binary is enough for Apple’s static analysis to flag the app as violating the rule.

CPython Community Response

Core developers discussed three possible mitigation strategies:

Make App‑Store compliance a design goal. Integrate a permanent patch into CPython that removes or guards the offending code, updating it whenever the store’s policies change.

Treat it as a distribution problem. Require third‑party packaging tools (e.g., Briefcase, py2app, Buildozer) to apply a patch during the build, leaving the upstream interpreter untouched.

Provide an optional, reversible patch. Add a configure flag such as --with-app-store-compliance (or --with-app-store-patch=PATH) that, when enabled for iOS/macOS builds, strips the itms-services handling code before the standard library is compiled.

Russell Keith‑Magee advocated for the third approach and proposed a new configure option --with-app-store-compliance. Alex Gaynor suggested a short‑lived PR that could be merged, documented, and later removed once the store’s rules evolve.

Implementation in CPython

On 25 June 2024, Keith‑Magee submitted pull request #120984, which introduces the --with-app-store-compliance configure flag. When the flag is enabled, a diff is applied that removes the itms-services handling code from urllib/parse.py. The flag defaults to disabled on most platforms but is automatically enabled for iOS and macOS builds. The change is slated to be included in Python 3.13, allowing developers to build a compliant interpreter without manual source edits.

Example of the Blocked Scheme

itms-services://?action=download-manifest&url=https://example.com/manifest.plist

This scheme is used for enterprise or test‑flight distribution of iOS apps and is explicitly forbidden in sandboxed App Store binaries.

Broader Implications

The incident illustrates how opaque platform review mechanisms can force open‑source projects to embed non‑functional work‑arounds, raising maintainability and security concerns. Similar automated checks exist on iOS, Android, and Windows (e.g., Windows Defender flagging PyInstaller‑generated binaries). The CPython community’s response—providing an optional build‑time patch—offers a pragmatic balance between developer convenience and compliance with evolving store policies.

Developers targeting Apple platforms should monitor CPython’s issue tracker for future compliance patches and consider using packaging tools that automatically apply the --with-app-store-compliance option when building for the App Store.