Create a Request to Fetch Metadata

ConstructionPreprocessRequest is passed to the /construction/preprocess endpoint so that a Rosetta implementation can determine which metadata it needs to request for construction.

Metadata provided in this object should NEVER be a product of live data (i.e. the caller must follow some network-specific data fetching strategy outside of the Construction API to populate required Metadata). If live data is required for construction, it MUST be fetched in the call to /construction/metadata.

ConstructionPreprocessResponse contains options that will be sent unmodified to /construction/metadata. If it is not necessary to make a request to /construction/metadata, options should be omitted.

Some blockchains require the PublicKey of particular AccountIdentifiers to construct a valid transaction. To fetch these PublicKeys, populate required_public_keys with the AccountIdentifiers associated with the desired PublicKeys. If it is not necessary to retrieve any PublicKeys for construction, required_public_keys should be omitted.