Testing Custom Server Routing + Data

This is a test using Express to pass data to routes via getInitialProps.

This code test was created from https://github.com/zeit/next.js/tree/canary/examples/custom-server-express

Test 1

When using Link component, you can see that some of the data (testObject and testArray - see server.js) are showing up as undefined when navigating to/from the two sample posts (also using the back/forward browser buttons - see console output). On refresh, they show correct values.

1. Open browser at localhost:3000
2. Click <Link> nav, see output. Does not show testObject and testArray unless page is reloaded.

When using the non Link nav, there is no such issue, testObject and testArray are passed correctly.

1. Open browser at localhost:3000
2. Click non <Link> nav, see output. Shows testObject and testArray correctly.

Conclusion, do not use <Link> with custom server implemenation?

Test 2

Curiously, in Safari (11.1), testObject fails to be passed getInitialProps when using the non Link nav and then using back/forward browser buttons:

1. Open safari at localhost:3000
2. click non Link nav, post 1
3. click non link nav, post 2
4. Now use Safari back/forward button and view results.

Question: what is the proper way to handle routing when using Express. <Link>? no <Link>, Router? There must be some combination that does not result in loss of initial props.