Enable python external package loading by default.

src/pyodide/BUILD.bazel

@@ -20,48 +20,12 @@ capnp_embed(
     deps = ["pyodide_packages_archive"],
 )
 
-copy_file(
-    name = "python_entrypoint_file",
-    src = "python-entrypoint.js",
-    out = "generated/python-entrypoint.js",
-)
-
-capnp_embed(
-    name = "python_entrypoint_file_embed",
-    src = "generated/python-entrypoint.js",
-    deps = ["python_entrypoint_file"],
-)
-
-copy_file(
-    name = "pyodide_extra_capnp_file",
-    src = "pyodide_extra.capnp",
-    out = "generated/pyodide_extra.capnp",
-)
-
-capnp_embed(
-    name = "pyodide_extra_file_embed",
-    src = "generated/pyodide_extra.capnp",
-    deps = ["pyodide_extra_capnp_file"],
-)
-
 capnp_embed(
     name = "pyodide_lock_file_embed",
     src = "generated/pyodide-lock.json",
     deps = ["pyodide-lock.js@rule"],
 )
 
-cc_capnp_library(
-    name = "pyodide_extra_capnp",
-    srcs = ["generated/pyodide_extra.capnp"],
-    visibility = ["//visibility:public"],
-    deps = [
-        ":pyodide_extra_file_embed",
-        ":pyodide_lock_file_embed",
-        ":pyodide_packages_archive_embed",
-        ":python_entrypoint_file_embed",
-    ],
-)
-
 copy_file(
     name = "pyodide.asm.wasm@rule",
     src = "@pyodide//:pyodide/pyodide.asm.wasm",

src/workerd/api/BUILD.bazel

@@ -85,7 +85,6 @@ wd_cc_library(
     hdrs = [
         "modules.h",
         "rtti.h",
-        "//src/pyodide:generated/pyodide_extra.capnp.h",
         "//src/workerd/server:workerd.capnp.h",
     ],
     visibility = ["//visibility:public"],
@@ -96,7 +95,6 @@ wd_cc_library(
         ":pyodide",
         ":r2",
         "//src/pyodide",
-        "//src/pyodide:pyodide_extra_capnp",
         "//src/workerd/api/node",
         "//src/workerd/io",
         "//src/workerd/jsg:rtti",
@@ -140,7 +138,6 @@ wd_cc_library(
     implementation_deps = ["//src/workerd/util:string-buffer"],
     visibility = ["//visibility:public"],
     deps = [
-        "//src/pyodide:pyodide_extra_capnp",
         "//src/workerd/io",
         "//src/workerd/jsg",
         "//src/workerd/server:workerd_capnp",

src/workerd/api/pyodide/pyodide.c++

@@ -521,4 +521,18 @@ bool hasPythonModules(capnp::List<server::config::Worker::Module>::Reader module
   return false;
 }
 
+kj::StringPtr getPythonEntrypoint() {
+  return R"JS_SCRIPT(
+// The entrypoint to a worker has to be an ES6 module (well, ignoring service
+// workers). For Python workers, we use this file as the ES6 entrypoint.
+//
+// This file is treated as part of the user bundle and cannot import internal
+// modules. Any imports from this file must be user-visible. To deal with this,
+// we delegate the implementation to `python-entrypoint-helper` which is a
+// BUILTIN module that can see our INTERNAL modules.
+
+export { default } from 'pyodide:python-entrypoint-helper';
+  )JS_SCRIPT"_kj;
+}
+
 }  // namespace workerd::api::pyodide

src/workerd/api/pyodide/pyodide.h

@@ -424,6 +424,8 @@ jsg::Ref<PyodideMetadataReader> makePyodideMetadataReader(Worker::Reader conf,
 
 bool hasPythonModules(capnp::List<server::config::Worker::Module>::Reader modules);
 
+kj::StringPtr getPythonEntrypoint();
+
 #define EW_PYODIDE_ISOLATE_TYPES                                                                   \
   api::pyodide::ReadOnlyBuffer, api::pyodide::PyodideMetadataReader,                               \
       api::pyodide::ArtifactBundler, api::pyodide::DiskCache,                                      \

src/workerd/server/BUILD.bazel

@@ -51,7 +51,6 @@ wd_cc_binary(
         ":v8-platform-impl",
         ":workerd-meta_capnp",
         ":workerd_capnp",
-        "//src/pyodide:pyodide_extra_capnp",
         "//src/rust/cxx-integration",
         "//src/workerd/util:autogate",
         "//src/workerd/util:perfetto",

src/workerd/server/workerd-api.c++

@@ -46,8 +46,6 @@
 #include <workerd/util/thread-scopes.h>
 #include <workerd/util/use-perfetto-categories.h>
 
-#include <pyodide/generated/pyodide_extra.capnp.h>
-
 #include <kj/compat/http.h>
 #include <kj/compat/tls.h>
 #include <kj/compat/url.h>
@@ -553,7 +551,7 @@ void WorkerdApi::compileModules(jsg::Lock& lockParam,
         auto mainModule = confModules.begin();
         capnp::MallocMessageBuilder message;
         auto module = message.getRoot<config::Worker::Module>();
-        module.setEsModule(PYTHON_ENTRYPOINT);
+        module.setEsModule(getPythonEntrypoint());
         auto info = tryCompileModule(lockParam, module, modules->getObserver(), featureFlags);
         auto path = kj::Path::parse(mainModule->getName());
         modules->add(path, kj::mv(KJ_REQUIRE_NONNULL(info)));
@@ -565,14 +563,8 @@ void WorkerdApi::compileModules(jsg::Lock& lockParam,
           jsg::ModuleRegistry::Type::INTERNAL);
 
       // Inject packages tar file
-      if (featureFlags.getPythonExternalPackages()) {
-        modules->addBuiltinModule("pyodide-internal:packages_tar_reader", "export default { }"_kj,
-            workerd::jsg::ModuleRegistry::Type::INTERNAL, {});
-      } else {
-        modules->addBuiltinModule("pyodide-internal:packages_tar_reader",
-            jsg::alloc<ReadOnlyBuffer>(PYODIDE_PACKAGES_TAR.get()),
-            workerd::jsg::ModuleRegistry::Type::INTERNAL);
-      }
+      modules->addBuiltinModule("pyodide-internal:packages_tar_reader", "export default { }"_kj,
+          workerd::jsg::ModuleRegistry::Type::INTERNAL, {});
 
       // Inject artifact bundler.
       modules->addBuiltinModule("pyodide-internal:artifacts",
@@ -967,7 +959,7 @@ kj::Own<jsg::modules::ModuleRegistry> WorkerdApi::initializeBundleModuleRegistry
         KJ_REQUIRE(featureFlags.getPythonWorkers(),
             "The python_workers compatibility flag is required to use Python.");
         hasPythonModules = true;
-        bundleBuilder.addEsmModule(def.getName(), kj::str(PYTHON_ENTRYPOINT).releaseArray());
+        bundleBuilder.addEsmModule(def.getName(), kj::str(getPythonEntrypoint()).releaseArray());
         break;
       }
       case config::Worker::Module::PYTHON_REQUIREMENT: {