fix(): use console warning for zoid version mismatch

[blumk]

Fixes #225

For various reasons it's not always possible to deploy the parent / child at the same time.

Currently zoid crashes on a version mismatch even if there are no breaking changes between two versions.

Rationale for using console.warn() instead of new Error():

• In case of a breaking change the software still crashes with a warning on console
• non-breaking changes allow independent deployments (think of a security patch)

Ultimately it's the developers responsibility to make sure that the software is working as intended and that there are no console warnings.

[songz]

@bluepnume any reason why this wasn't merged? Does PayPal want to intentionally throw error on version mismatch?

[bluepnume]

@songz -- it's a choice between:

a) Fail at this point with a clear error message
b) Fail at some future indeterminate point due to some unforeseen incompatibility between the messaging protocol in two different zoid versions (e.g. some new key expected in payloads, etc.)

We were hitting b) a lot. So a) at least gives a super clear reason.

Typically with zoid, the expectation is you create a CDN script with your component + the zoid library, and make sure you're loading the exact same CDN script in the parent window and in any child frames. That avoids any such compatibility issues, and it also has performance benefits (you usually don't want to force your user to download multiple versions of zoid).

^ We should probably document the above a little better.

[akshay-8d66]

Typically with zoid, the expectation is you create a CDN script with your component + the zoid library, and make sure you're loading the exact same CDN script in the parent window and in any child frames.

Could you point out where paypal/paypal-checkout-components does this.

[gregjopa]

We updated the logic for version mismatch errors to only throw an error when the major version is different. See this PR: #425.

I'm going to close this out. Please open a new issue if you are still having trouble with the error handling around version mismatches between the parent page and the child iframe.