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Final Class A signer that delegates all signing to the Crossmint backend via API key authentication. 
final class CrossmintApiKeySigner implements CrossmintWalletApprovalSigner
This signer never performs local signing. When a wallet uses an API key signer, the Crossmint backend automatically approves transactions and signatures on behalf of the user. Calling signMessage or signTransaction directly will throw; signing is handled server-side during the transaction/signature creation API call.

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Constructors

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CrossmintApiKeySigner

const CrossmintApiKeySigner({String? locator})
Creates an API key signer.

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Properties

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type

String get type

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locator

final String locator

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Methods

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signMessage

Future<Object> signMessage(String message)
Always throws — API key signers do not support local message signing.

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signTransaction

Future<Object> signTransaction(String transaction)
Always throws — API key signers do not support local transaction signing.