feat(python-sdk): move template build-context uploads onto pyqwest

[mishushakov]

What

Stacked on #1602 (which is stacked on #1601). Migrates the template build-context uploads (streaming the build archive to S3 presigned URLs in build_api.upload_file) onto pyqwest via its httpx-compatible transport adapter.

Originally deferred from #1601 because S3 presigned URLs reject chunked transfer encoding and Content-Length framing through reqwest was unverified. Verified at the wire level (raw-socket capture server): httpx's Content-Length — derived from the spooled archive (sync) or set explicitly on the async-iterator body (async) — is forwarded by the adapter and reqwest keeps Content-Length framing for streamed bodies, no chunked fallback.

Note

Rebased onto #1601, which maps httpx.Proxy onto pyqwest's Proxy object and therefore requires pyqwest 0.8 (released, and locked in #1601). The only change here is following the rename — this PR builds its transport from proxy_to_config(...) instead of proxy_to_url(...).

How

• e2b/template_sync/build_api.py / template_async/build_api.py: upload_file uses a one-off pyqwest transport (ApiPyqwestTransport from feat(python-sdk): move the REST API client onto pyqwest's httpx transport adapter #1601) instead of the generated client's httpx transport.
• verify_ssl=False on the generated client is no longer honored for uploads (pyqwest has no insecure-TLS option), and http2=False is gone (S3 negotiates HTTP/1.1 via ALPN anyway).
• The 1-hour upload timeout now bounds the entire upload rather than each socket write — arguably the intended meaning for that endpoint.

Testing

• tests/{sync,async}/*/test_upload_file.py (the [JS SDK] uploadFile uses chunked transfer encoding, causing 501 NotImplemented on S3 presigned PUT URLs #1243 regression tests — Content-Length present and equal to the body, no chunked encoding) pass through pyqwest; the capture handlers now compare header names case-insensitively since hyper lowercases them where httpcore title-cased.
• Lint (ruff), typecheck (ty), unit suite: green.

Usage example

No API changes — template builds upload their context exactly as before:

from e2b import Template

template = Template().from_image("ubuntu:22.04").copy("data/", "/data")
Template.build(template, alias="my-template")   # archive upload now goes through pyqwest

🤖 Generated with Claude Code

[changeset-bot]

🦋 Changeset detected

Latest commit: ada7677

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@e2b/python-sdk	Minor

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[cursor]

PR Summary

Medium Risk
Upload path swap plus timeout semantics change and loss of verify_ssl=False for presigned PUTs could affect large builds or TLS-debug setups; S3 Content-Length contract is covered by existing regression tests.

Overview
Template build-context uploads to S3 presigned URLs in sync and async upload_file now use a one-off pyqwest httpx transport (ApiPyqwestTransport / AsyncApiPyqwestTransport) instead of the default httpx stack. Proxy settings come from proxy_to_config on the API client’s _proxy.

Content-Length framing for streamed archive bodies is unchanged (required so S3 does not get chunked encoding). The default 1-hour upload timeout now applies to the whole request, not per socket write. verify_ssl=False on the generated client is not applied to these uploads because pyqwest has no insecure-TLS path. http2=False is removed for uploads.

Upload regression tests normalize header names to lowercase because pyqwest/hyper lowercases them where httpcore title-cased them.

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[github-actions]

Package Artifacts

Built from 7ef7a31. Download artifacts from this workflow run.

JS SDK (e2b@2.38.1-migrate-template-uploads-to-pyqwest.0):

npm install ./e2b-2.38.1-migrate-template-uploads-to-pyqwest.0.tgz

CLI (@e2b/cli@2.16.2-migrate-template-uploads-to-pyqwest.0):

npm install ./e2b-cli-2.16.2-migrate-template-uploads-to-pyqwest.0.tgz

Python SDK (e2b==2.37.0+migrate.template.uploads.to.pyqwest):

pip install ./e2b-2.37.0+migrate.template.uploads.to.pyqwest-py3-none-any.whl

[linear-code]

SDK-268