feat: Add Proxy support for @powersync/node

[Chriztiaan]

Node package

Introduced support for specifying proxy environment variables for the connection methods. HTTP will use EnvHttpProxyAgent(see https://github.com/nodejs/undici/pull/2994/files#diff-e75b15c5fd859828aa0413c608603d1152bd54320aabd8ec8f73b023c924d0db) from undici and Websockets will use proxy-agent. In both cases the libraries automatically use the correct env variable. For HTTP this will typically be HTTP_PROXY or HTTPS_PROXY and for Websockets it will be WS_PROXY or WSS_PROXY, with other known options also available.

The HTTP dispatcher can be overridden with the dispatcher connect() option:

await db.connect(new DemoConnector(), {
    connectionMethod: SyncStreamConnectionMethod.HTTP,
    dispatcher: new MyAgent()
  });

Common package

To support specifying a custom option for the connect method of the Node package, I needed to ensure that config is passed along correctly.

Testing

Easiest way to test is to create a a session access token with another demo and use it in the node demo's connector.

MITM with custom CA

HTTPS_PROXY=http://localhost:8082/  # change to `https://localhost:8080/` to test https proxy protocol
SYNC_SERVICE=https://xxxxxx.powersync.staging.journeyapps.com/
SSL_CERT_FILE=somepath/ca-cert.pem  # pem from mitmproxy

Running:
Terminal 1

mitmproxy --set stream_large_bodies=0 --listen-port 8082

Terminal 2

node --use-openssl-ca --loader ts-node/esm -r dotenv/config src/main.ts

[changeset-bot]

🦋 Changeset detected

Latest commit: b2c0dcd

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

This PR includes changesets to release 7 packages

Name	Type
@powersync/node	Minor
@powersync/common	Minor
@powersync/op-sqlite	Patch
@powersync/react-native	Patch
@powersync/tanstack-react-query	Patch
@powersync/web	Patch
@powersync/diagnostics-app	Patch

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