feat: Support async faucet transactions

This adds support for asynchronous faucet transactions. This will
make faucet transactions consistent with other transactions and will
make them more stable, as we can poll for the status on the SDK side
rather than on the server side.

```
faucet_tx = wallet.faucet
faucet_tx.wait!
```

or

```
wallet.faucet.wait!
```

lib/coinbase/address.rb

@@ -91,11 +91,16 @@ def transactions
     # @raise [Coinbase::FaucetLimitReachedError] If the faucet limit has been reached for the address or user.
     # @raise [Coinbase::Client::ApiError] If an unexpected error occurs while requesting faucet funds.
     def faucet(asset_id: nil)
-      opts = { asset_id: asset_id }.compact
-
       Coinbase.call_api do
         Coinbase::FaucetTransaction.new(
-          addresses_api.request_external_faucet_funds(network.normalized_id, id, opts)
+          addresses_api.request_external_faucet_funds(
+            network.normalized_id,
+            id,
+            {
+              asset_id: asset_id,
+              skip_wait: true
+            }.compact
+          )
         )
       end
     end

lib/coinbase/faucet_transaction.rb

@@ -12,22 +12,80 @@ def initialize(model)
       @model = model
     end
 
+    # Returns the Faucet transaction.
+    # @return [Coinbase::Transaction] The Faucet transaction
+    def transaction
+      @transaction ||= Coinbase::Transaction.new(@model.transaction)
+    end
+
+    # Returns the status of the Faucet transaction.
+    # @return [Symbol] The status
+    def status
+      transaction.status
+    end
+
     # Returns the transaction hash.
     # @return [String] The onchain transaction hash
     def transaction_hash
-      model.transaction_hash
+      transaction.transaction_hash
     end
 
     # Returns the link to the transaction on the blockchain explorer.
     # @return [String] The link to the transaction on the blockchain explorer
     def transaction_link
-      model.transaction_link
+      transaction.transaction_link
+    end
+
+    # Returns the Network of the Transaction.
+    # @return [Coinbase::Network] The Network
+    def network
+      transaction.network
+    end
+
+    # Waits until the FaucetTransaction is completed or failed by polling on the given interval.
+    # @param interval_seconds [Integer] The interval at which to poll the Network, in seconds
+    # @param timeout_seconds [Integer] The maximum amount of time to wait for the Transfer to complete, in seconds
+    # @raise [Timeout::Error] if the FaucetTransaction takes longer than the given timeout
+    # @return [Transfer] The completed Transfer object
+    def wait!(interval_seconds = 0.2, timeout_seconds = 20)
+      start_time = Time.now
+
+      loop do
+        reload
+
+        return self if transaction.terminal_state?
+
+        raise Timeout::Error, 'Faucet transaction timed out' if Time.now - start_time > timeout_seconds
+
+        self.sleep interval_seconds
+      end
+
+      self
+    end
+
+    def reload
+      @model = Coinbase.call_api do
+        addresses_api.get_faucet_transaction(
+          network.normalized_id,
+          transaction.to_address_id,
+          transaction_hash
+        )
+      end
+
+      @transaction = Coinbase::Transaction.new(@model.transaction)
+
+      self
     end
 
     # Returns a String representation of the FaucetTransaction.
     # @return [String] a String representation of the FaucetTransaction
     def to_s
-      "Coinbase::FaucetTransaction{transaction_hash: '#{transaction_hash}', transaction_link: '#{transaction_link}'}"
+      Coinbase.pretty_print_object(
+        self.class,
+        status: transaction.status,
+        transaction_hash: transaction_hash,
+        transaction_link: transaction_link
+      )
     end
 
     # Same as to_s.
@@ -38,6 +96,8 @@ def inspect
 
     private
 
-    attr_reader :model
+    def addresses_api
+      @addresses_api ||= Coinbase::Client::ExternalAddressesApi.new(Coinbase.configuration.api_client)
+    end
   end
 end

lib/coinbase/transaction.rb

@@ -41,6 +41,12 @@ def initialize(model)
       @model = model
     end
 
+    # Returns the Network of the Transaction.
+    # @return [Coinbase::Network] The Network
+    def network
+      @network ||= Coinbase::Network.from_id(@model.network_id)
+    end
+
     # Returns the Unsigned Payload of the Transaction.
     # @return [String] The Unsigned Payload
     def unsigned_payload

spec/factories/faucet_transaction.rb

@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+FactoryBot.define do
+  factory :faucet_tx_model, class: Coinbase::Client::FaucetTransaction do
+    transient do
+      status { 'broadcasted' }
+      network_trait { :base_sepolia }
+      to_address_id { nil }
+      transaction_hash { nil }
+    end
+
+    # Default traits
+    base_sepolia
+    pending
+
+    TX_TRAITS.each do |status|
+      trait status do
+        status { status }
+      end
+    end
+
+    NETWORK_TRAITS.each do |network|
+      trait network do
+        network_trait { network }
+      end
+    end
+
+    after(:build) do |transfer, transients|
+      transfer.transaction = build(
+        :transaction_model,
+        transients.status,
+        transients.network_trait,
+        {
+          to_address_id: transients.to_address_id,
+          transaction_hash: transients.transaction_hash
+        }.compact
+      )
+    end
+  end
+end

spec/factories/transaction.rb

@@ -10,6 +10,13 @@
 
     # Default trait.
     pending
+    base_sepolia
+
+    NETWORK_TRAITS.each do |network|
+      trait network do
+        network_id { Coinbase.normalize_network(network) }
+      end
+    end
 
     trait :pending do
       status { 'pending' }

spec/support/shared_examples/address_balances.rb

@@ -141,18 +141,18 @@
   end
 
   describe '#faucet' do
-    let(:tx_hash) { '0xdeadbeef' }
     let(:faucet_tx) do
-      instance_double(Coinbase::Client::FaucetTransaction, transaction_hash: tx_hash)
+      build(:faucet_tx_model, network_id, :broadcasted, to_address_id: address_id)
     end
+    let(:tx_hash) { faucet_tx.transaction.transaction_hash }
 
     context 'when the request is successful' do
       subject(:faucet_response) { address.faucet }
 
       before do
         allow(external_addresses_api)
           .to receive(:request_external_faucet_funds)
-          .with(normalized_network_id, address_id, {})
+          .with(normalized_network_id, address_id, { skip_wait: true })
           .and_return(faucet_tx)
       end
 
@@ -161,7 +161,7 @@
 
         expect(external_addresses_api)
           .to have_received(:request_external_faucet_funds)
-          .with(normalized_network_id, address_id, {})
+          .with(normalized_network_id, address_id, { skip_wait: true })
       end
 
       it 'returns the faucet transaction' do
@@ -173,11 +173,34 @@
       end
     end
 
-    context 'when the request is unsuccesful' do
+    context 'when using specified asset' do
+      subject(:faucet_response) { address.faucet(asset_id: :usdc) }
+
+      before do
+        allow(external_addresses_api)
+          .to receive(:request_external_faucet_funds)
+          .with(normalized_network_id, address_id, { asset_id: :usdc, skip_wait: true })
+          .and_return(faucet_tx)
+      end
+
+      it 'requests external faucet funds for the address for the specified asset' do
+        faucet_response
+
+        expect(external_addresses_api)
+          .to have_received(:request_external_faucet_funds)
+          .with(normalized_network_id, address_id, { asset_id: :usdc, skip_wait: true })
+      end
+
+      it 'returns the faucet transaction' do
+        expect(faucet_response).to be_a(Coinbase::FaucetTransaction)
+      end
+    end
+
+    context 'when the request is unsuccessful' do
       before do
         allow(external_addresses_api)
           .to receive(:request_external_faucet_funds)
-          .with(normalized_network_id, address_id, {})
+          .with(normalized_network_id, address_id, { skip_wait: true })
           .and_raise(api_error)
       end
 

spec/unit/coinbase/faucet_transaction_spec.rb

@@ -3,37 +3,135 @@
 describe Coinbase::FaucetTransaction do
   subject(:faucet_transaction) { described_class.new(model) }
 
+  let(:network_id) { :base_sepolia }
   let(:transaction_hash) { '0x6c087c1676e8269dd81e0777244584d0cbfd39b6997b3477242a008fa9349e11' }
   let(:transaction_link) { "https://sepolia.basescan.org/tx/#{transaction_hash}" }
-  let(:model) do
-    Coinbase::Client::FaucetTransaction.new(
+  let(:address_id) { Eth::Key.new.address.to_s }
+  let(:transaction_model) do
+    build(
+      :transaction_model,
+      :broadcasted,
+      network_id,
+      to_address_id: address_id,
       transaction_hash: transaction_hash,
       transaction_link: transaction_link
     )
   end
+  let(:model) do
+    Coinbase::Client::FaucetTransaction.new(transaction: transaction_model)
+  end
+
+  let(:external_addresses_api) { instance_double(Coinbase::Client::ExternalAddressesApi) }
+
+  before do
+    allow(Coinbase::Client::ExternalAddressesApi).to receive(:new).and_return(external_addresses_api)
+  end
 
   describe '#initialize' do
     it 'initializes a new FaucetTransaction' do
       expect(faucet_transaction).to be_a(described_class)
     end
   end
 
+  describe '#transaction' do
+    it 'returns the transaction' do
+      expect(faucet_transaction.transaction).to be_a(Coinbase::Transaction)
+    end
+  end
+
   describe '#transaction_hash' do
     it 'returns the transaction hash' do
       expect(faucet_transaction.transaction_hash).to eq(transaction_hash)
     end
   end
 
+  describe '#status' do
+    it 'returns the transaction status' do
+      expect(faucet_transaction.status).to eq(Coinbase::Transaction::Status::BROADCAST)
+    end
+  end
+
+
   describe '#transaction_link' do
     it 'returns the transaction link' do
       expect(faucet_transaction.transaction_link).to eq(transaction_link)
     end
   end
 
+  describe '#network' do
+    it 'returns the network' do
+      expect(faucet_transaction.network).to be_a(Coinbase::Network)
+    end
+  end
+
+  describe '#reload' do
+    let(:updated_transaction_model) do
+      build(
+        :transaction_model,
+        :completed,
+        to_address_id: address_id,
+        transaction_hash: transaction_hash,
+        transaction_link: transaction_link
+      )
+    end
+    let(:updated_model) do
+      Coinbase::Client::FaucetTransaction.new(transaction: updated_transaction_model)
+    end
+
+    before do
+      allow(external_addresses_api)
+        .to receive(:get_faucet_transaction)
+        .with('base-sepolia', address_id, transaction_hash)
+        .and_return(updated_model)
+    end
+
+    it 'updates the faucet transaction' do
+      expect(faucet_transaction.reload.transaction.status).to eq(Coinbase::Transaction::Status::COMPLETE)
+    end
+  end
+
+  describe '#wait!' do
+    before do
+      allow(faucet_transaction).to receive(:sleep) # rubocop:disable RSpec/SubjectStub
+
+      allow(external_addresses_api)
+        .to receive(:get_faucet_transaction)
+        .with('base-sepolia', address_id, transaction_hash)
+        .and_return(model, model, updated_model)
+    end
+
+    context 'when the faucet transaction is completed' do
+      let(:updated_model) { build(:faucet_tx_model, network_id, :completed) }
+
+      it 'returns the completed FaucetTransaction' do
+        expect(faucet_transaction.wait!.status).to eq(Coinbase::Transaction::Status::COMPLETE)
+      end
+    end
+
+    context 'when the faucet transaction is failed' do
+      let(:updated_model) { build(:faucet_tx_model, network_id, :failed) }
+
+      it 'returns the failed FaucetTransaction' do
+        expect(faucet_transaction.wait!.status).to eq(Coinbase::Transaction::Status::FAILED)
+      end
+    end
+
+    context 'when the faucet transaction times out' do
+      let(:updated_model) { build(:faucet_tx_model, network_id, :broadcasted) }
+
+      it 'raises a Timeout::Error' do
+        expect { faucet_transaction.wait!(0.2, 0.00001) }.to raise_error(Timeout::Error, 'Faucet transaction timed out')
+      end
+    end
+  end
+
   describe '#to_s' do
     it 'returns a string representation of the FaucetTransaction' do
-      expect(faucet_transaction.to_s).to eq(
-        "Coinbase::FaucetTransaction{transaction_hash: '#{transaction_hash}', transaction_link: '#{transaction_link}'}"
+      expect(faucet_transaction.to_s).to include(
+        'Coinbase::FaucetTransaction',
+        transaction_hash,
+        transaction_link,
+        'broadcast'
       )
     end
   end

spec/unit/coinbase/smart_contract_spec.rb

@@ -866,7 +866,7 @@ def build_nested_solidity_value(hash)
   end
 
   describe '#inspect' do
-    it 'includes smart contractdetails' do
+    it 'includes smart contract details' do
       expect(smart_contract.inspect).to include(
         address_id,
         Coinbase.to_sym(network_id).to_s,