Add invoke function

Author: tupui

src/soroban/__init__.py

@@ -1 +1,4 @@
+from soroban.invoke import *
 from soroban.models import *
+
+__all__ = ["invoke"]

src/soroban/invoke.py

@@ -0,0 +1,62 @@
+import time
+
+import stellar_sdk
+from stellar_sdk import xdr
+from stellar_sdk.exceptions import SdkError
+from stellar_sdk.soroban_rpc import GetTransactionStatus, SendTransactionStatus
+
+import soroban.models as soroban_models
+
+__all__ = ["invoke"]
+
+
+def invoke(
+    contract_id: str,
+    function_name: str,
+    args: list[xdr.SCVal],
+    *,
+    source_account: stellar_sdk.Keypair | str | None = None,
+    network: soroban_models.NetworkConfig | None = None,
+):
+    identity = soroban_models.Identity.from_source_account(account=source_account)
+
+    soroban_server = stellar_sdk.SorobanServer(network.soroban_rpc_url)
+    source_account = soroban_server.load_account(identity.public_key)
+
+    tx = (
+        stellar_sdk.TransactionBuilder(
+            source_account, network.passphrase, base_fee=network.base_fee
+        )
+        .add_time_bounds(0, 0)
+        .append_invoke_contract_function_op(
+            contract_id=contract_id,
+            function_name=function_name,
+            parameters=args,
+        )
+        .build()
+    )
+    tx = soroban_server.prepare_transaction(tx)
+    tx.sign(identity.keypair)
+    transaction = soroban_server.send_transaction(tx)
+
+    if transaction.status != SendTransactionStatus.PENDING:
+        raise SdkError("Failed to send transaction")
+
+    i = 0
+    while i < 10:
+        transaction_result = soroban_server.get_transaction(transaction.hash)
+        if transaction_result.status != GetTransactionStatus.NOT_FOUND:
+            break
+        time.sleep(3)
+        i += 1
+    else:
+        raise SdkError("Timeout: could not validate transaction")
+
+    if transaction_result.status == GetTransactionStatus.SUCCESS:
+        transaction_meta = xdr.TransactionMeta.from_xdr(
+            transaction_result.result_meta_xdr
+        )
+        if transaction_meta.v3.soroban_meta.return_value.type == xdr.SCValType.SCV_VOID:
+            return transaction_meta
+    else:
+        raise SdkError(f"Transaction failed: {transaction_result.result_xdr}")

src/soroban/models.py

@@ -46,6 +46,7 @@ def from_source_account(
 class NetworkConfig(BaseSettings):
     soroban_rpc_url: HttpUrl = HttpUrl("https://soroban-testnet.stellar.org:443")
     passphrase: str = Network.TESTNET_NETWORK_PASSPHRASE
+    base_fee: int = 100
 
     model_config = SettingsConfigDict(env_file="network.toml")