Sync Python examples

Showcase of the sync Dex Python SDK surface (Client / Worker) next to the primary async examples under examples/python/.

Targets dex-python-sdk==0.6.0. Requires Python 3.11+.

The samples use concrete SDK errors for missing, inactive, and duplicate Flows instead of inspecting Dex sub-status metadata.

Six Flows:

Demo	Route prefix	Notes
Basic	`/primitives/step`	smallest Flow
Money transfer	`/products/money-transfer`	saga
Engagement	`/products/engagement`	channels + RPC
Subscription	`/products/subscription`	timers
Parent–child	`/patterns/parent-child`	sync `Client` inside `Step.execute`
Interruptible	`/patterns/interruptible`	interrupt RPC

Defaults: HTTP 127.0.0.1:8081 (the async app uses 8080). The Worker uses pull streams and needs only an outbound connection to the Dex Server.

Run

From examples/python (shared uv project):

dexcli dev
# Indexed Attributes — same as the async README

uv sync --locked
uv run --frozen python sync-python/main.py

Env overrides: DEX_FLOW_SERVICE_ADDRESS, DEX_SYNC_EXAMPLES_HTTP_ADDRESS, and DEX_SYNC_BLOB_CACHE_DIR.

# from examples/python, with Dex running
DEX_FLOW_SERVICE_ADDRESS=127.0.0.1:8801 \
  uv run --frozen pytest sync-python/sync_tests/integ -v

Or run the full e2e suite (make e2eTests), which includes these sync integ tests.