Ensure correct metadata for parsing (archive nodes, historical queries)

There are several blocks throughout the chain that produce the following error when you try to fetch them:

2019-04-16 20:34:56        RPC-CORE: getBlock (hash: Hash): SignedBlock:: Source is too large
ExtError: getBlock (hash: Hash): SignedBlock:: Source is too large
    at call (/Users/self/dev/polkadot/statd/node_modules/@polkadot/rpc-core/index.js:134:15)
    at processTicksAndRejections (internal/process/next_tick.js:81:5)

This code will recreate the problem:

    const hash = new Hash(
        '0x6f6f9bba0eed8e3ae9446c37eee763f93118b52a315a7b46090453ba6288da1f'
    );
    api.rpc.chain.getBlock(hash)

Also, you will notice there is no then or catch on the getBlock promise. That is because the above error does not actually land in the catch block. It gets handled and logged by the library itself, which makes it more difficult for me to handle the error in my code.

[Swader]

Would this help?

https://github.com/paritytech/substrate-api-sidecar/blob/master/src/ApiHandler.ts

[jacogr]

I am currently sync-ing with archive mode, so will be looking at this one as well as https://github.com/polkadot-js/api/issues/846 ASAP. (They have been hanging for way too long)