Chains

Network configurations and chain constants

The Seismic SDK provides pre-configured network settings and utilities for connecting to Seismic chains. Chain configurations encapsulate RPC endpoints, WebSocket URLs, chain IDs, and convenience methods for creating clients.

Overview

Instead of manually passing RPC URLs and chain IDs when creating clients, you can use pre-defined chain configurations:

import os
from seismic_web3 import SEISMIC_TESTNET, SANVIL, PrivateKey

pk = PrivateKey.from_hex_str(os.environ["PRIVATE_KEY"])

# Connect to testnet
w3 = SEISMIC_TESTNET.wallet_client(pk)

# Connect to local Sanvil
w3 = SANVIL.wallet_client(pk)

Components

Chain Configurations

Component	Description
ChainConfig	Immutable dataclass for network configuration
SEISMIC_TESTNET	Public testnet configuration (GCP-1)
SANVIL	Local development network configuration
make_seismic_testnet	Factory for alternate testnet instances

Protocol Constants

Constant	Description
SEISMIC_TX_TYPE	Transaction type byte for Seismic transactions

Quick Start

Using Pre-Defined Chains

import os
from seismic_web3 import SEISMIC_TESTNET, PrivateKey

pk = PrivateKey.from_hex_str(os.environ["PRIVATE_KEY"])

# Wallet client (requires private key)
w3 = SEISMIC_TESTNET.wallet_client(pk)

# Async wallet (auto-selects ws_url when ws=True)
w3 = await SEISMIC_TESTNET.async_wallet_client(pk, ws=True)

# Public client (no private key needed)
public = SEISMIC_TESTNET.public_client()

Accessing Chain Properties

from seismic_web3 import SEISMIC_TESTNET, SANVIL

# Testnet properties
SEISMIC_TESTNET.rpc_url   # "https://gcp-1.seismictest.net/rpc"
SEISMIC_TESTNET.ws_url    # "wss://gcp-1.seismictest.net/ws"
SEISMIC_TESTNET.chain_id  # 5124
SEISMIC_TESTNET.name      # "Seismic Testnet (GCP-1)"

# Sanvil properties
SANVIL.rpc_url   # "http://127.0.0.1:8545"
SANVIL.ws_url    # "ws://127.0.0.1:8545"
SANVIL.chain_id  # 31337
SANVIL.name      # "Sanvil (local)"

Alternate Testnet Instances

from seismic_web3 import make_seismic_testnet

# Connect to different GCP testnet instances
testnet_2 = make_seismic_testnet(2)  # gcp-2.seismictest.net
testnet_3 = make_seismic_testnet(3)  # gcp-3.seismictest.net

w3 = testnet_2.wallet_client(pk)

Custom Chains

from seismic_web3 import ChainConfig, PrivateKey

custom = ChainConfig(
    chain_id=5124,
    rpc_url="https://gcp-1.seismictest.net/rpc",
    ws_url="wss://gcp-1.seismictest.net/ws",
    name="Seismic Testnet",
)

pk = PrivateKey(...)
w3 = custom.wallet_client(pk)

Client Creation Methods

All chain configurations provide convenience methods for creating clients:

Wallet Clients (Require Private Key)

# Sync wallet client
w3 = chain.wallet_client(private_key, encryption_sk=None)

# Async wallet client (HTTP)
w3 = await chain.async_wallet_client(private_key, encryption_sk=None, ws=False)

# Async wallet client (WebSocket)
w3 = await chain.async_wallet_client(private_key, ws=True)

Public Clients (No Private Key)

# Sync public client
public = chain.public_client()

# Async public client (HTTP)
public = chain.async_public_client(ws=False)

# Async public client (WebSocket)
public = chain.async_public_client(ws=True)

Chain IDs

The SDK defines constants for chain IDs used in transaction signing:

from seismic_web3 import SEISMIC_TESTNET_CHAIN_ID, SANVIL_CHAIN_ID

SEISMIC_TESTNET_CHAIN_ID  # 5124
SANVIL_CHAIN_ID           # 31337

These are automatically included in the chain configurations and used by the signing infrastructure.

Notes

• Chain configurations are immutable (frozen dataclasses)

• WebSocket support is automatic when ws=True and ws_url is configured

• HTTP endpoints are used as fallback if WebSocket URL is unavailable

• All methods return standard web3.py instances with the w3.seismic namespace attached

See Also

• Client Creation - Detailed client setup documentation

• Wallet Client - Full wallet client capabilities

• Public Client - Read-only client features

• PrivateKey - Private key type documentation