Client

Overview

The Client class provides the primary programmatic interface to the Opinion prediction market infrastructure. Configuration accuracy during initialization determines operational capability and security posture.

Basic Initialization

Minimal Configuration

from opinion_clob_sdk import Client

client = Client(
    host='https://proxy.opinion.trade:8443',
    apikey='your_api_key_here',
    chain_id=56,
    rpc_url='https://bsc-dataseed.binance.org',
    private_key='0x...',
    multi_sig_addr='0x...'
)

Required Parameters

host

Type: str

Description: CLOB API endpoint URL for HTTP communication.

Production Value:

host='https://proxy.opinion.trade:8443'

Endpoint Functions:

• Market data query routing

• Order submission and cancellation processing

• Position and balance data retrieval

apikey

Type: str

Description: Bearer token for API authentication and authorization.

Acquisition: Contact Opinion Labs at [email protected] for API access provisioning.

Security Best Practices:

import os
from dotenv import load_dotenv

load_dotenv()
apikey = os.getenv('API_KEY')  # Never hardcode!

chain_id

Type: int

Description: The blockchain network identifier.

Supported Values:

from opinion_clob_sdk import CHAIN_ID_BNB_MAINNET

chain_id = CHAIN_ID_BNB_MAINNET  # 56

Current Support:

• 56 - BNB Chain (BSC) Mainnet

rpc_url

Type: str

Description: JSON-RPC endpoint URL for BNB Chain node communication.

Available Providers:

# Public RPC endpoints (development and testing)
rpc_url = 'https://bsc-dataseed.binance.org'
rpc_url = 'https://bsc.nodereal.io'

private_key

Type: str

Description: secp256k1 private key for ECDSA signature generation (order signing and transaction authorization).

Format Specification:

# 64-character hexadecimal string with 0x prefix (32 bytes)
private_key = '0x_______'

multi_sig_addr

Type: str (ChecksumAddress)

Description: Ethereum address (checksummed format) holding USDT collateral and outcome tokens.

Gnosis Safe (Multi-Signature)

client = Client(
    private_key='0x...',           # Safe owner's key
    multi_sig_addr='0x8F58a1ab...', # Safe contract address
    ...
)

Optional Parameters

conditional_tokens_addr

Type: Optional[ChecksumAddress]

Default: 0xAD1a38cEc043e70E83a3eC30443dB285ED10D774 (BNB Chain)

Description: The ConditionalTokens smart contract address for split/merge/redeem operations.

When to Override:

• Testing on custom networks

• Interacting with forked contracts

• Development environments

# Usually you can omit this (uses default)
client = Client(...)

# Override only if needed
client = Client(
    conditional_tokens_addr='0xCustomAddress...',
    ...
)

multisend_addr

Type: Optional[ChecksumAddress]

Default: 0x998739BFdAAdde7C933B942a68053933098f9EDa (BNB Chain)

Description: The Gnosis Safe MultiSend contract for batch transactions.

When to Override:

• Testing batch operations

• Custom Safe deployments

# Usually you can omit this (uses default)
client = Client(...)

market_cache_ttl_seconds

Type: int

Default: 60 (1 minute)

Description: Time-to-live for cached market data.

Tuning Guidelines:

# High-frequency trading (minimize stale data)
client = Client(market_cache_ttl_seconds=10, ...)

# Analytics/dashboards (reduce API load)
client = Client(market_cache_ttl_seconds=300, ...)

# One-time scripts (cache entire run)
client = Client(market_cache_ttl_seconds=3600, ...)

# Disable caching (always fresh data)
client = Client(market_cache_ttl_seconds=0, ...)

Trade-offs:

TTL	API Calls	Data Freshness	Use Case
0	Maximum	Real-time	HFT, critical decisions
60	Moderate	1-min delay OK	General trading
300+	Minimal	5-min+ delay OK	Analytics, monitoring

quote_token_cache_ttl_seconds

Type: int

Default: 3600 (1 hour)

Description: Time-to-live for cached quote token (currency) information.

Rationale: Quote tokens (USDT, etc.) rarely change, so aggressive caching is safe.

# Default is usually fine
client = Client(quote_token_cache_ttl_seconds=3600, ...)

Validation and Error Handling

Validate Configuration

from opinion_clob_sdk import Client, SUPPORTED_CHAIN_IDS
from opinion_clob_sdk.chain.exception import InvalidParamError

try:
    client = Client(
        host='https://proxy.opinion.trade:8443',
        apikey='test_key',
        chain_id=999,  # Invalid!
        rpc_url='https://bsc-dataseed.binance.org',
        private_key='0x...',
        multi_sig_addr='0x...'
    )
except InvalidParamError as e:
    print(f"Configuration error: {e}")
    print(f"Supported chain IDs: {SUPPORTED_CHAIN_IDS}")

Test Connection

client = Client(...)

# Test API connectivity
try:
    currencies = client.get_quote_tokens()
    print(f"✓ API connected: {len(currencies)} currencies available")
except Exception as e:
    print(f"✗ API connection failed: {e}")

# Test blockchain connectivity
try:
    from web3 import Web3
    w3 = Web3(Web3.HTTPProvider(client.rpc_url))
    block = w3.eth.block_number
    print(f"✓ RPC connected: current block {block}")
except Exception as e:
    print(f"✗ RPC connection failed: {e}")

# Test wallet
from web3 import Web3
account = Web3().eth.account.from_key(client.private_key)
print(f"✓ Wallet: {account.address}")
print(f"✓ Multi-sig: {client.multi_sig_addr}")

Common Initialization Errors

Error: Invalid Chain ID

# Error message
InvalidParamError: chain_id must be one of [56]

# Solution
client = Client(chain_id=56, ...)  # Use BNB Chain

Error: Invalid Private Key Format

# Common mistakes
private_key = 'ac0974bec...'  # Missing 0x prefix
private_key = '0xGGGG...'     # Invalid hex

# Correct format
private_key = '0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80'

Error: RPC Connection Failed

# Symptoms
requests.exceptions.ConnectionError: Max retries exceeded

# Solutions
1. Check internet connection
2. Try alternative RPC URL
3. Use paid RPC provider
4. Check firewall settings

Error: API Authentication Failed

# Error response
{"errno": 40100, "errmsg": "Invalid API key"}

# Solutions
1. Verify API key is correct
2. Check for extra whitespace
3. Ensure key is active
4. Contact [email protected]

Performance Optimization

Connection Pooling

# The SDK reuses HTTP connections automatically
# For long-running applications, create one client instance

# ✅ Good
client = Client(...)
for i in range(1000):
    markets = client.get_markets()

# ❌ Bad (creates 1000 connections)
for i in range(1000):
    client = Client(...)
    markets = client.get_markets()

Caching Strategy

# Aggressive caching for read-heavy workloads
client = Client(
    market_cache_ttl_seconds=300,      # 5 minutes
    quote_token_cache_ttl_seconds=3600 # 1 hour
)

# Minimal caching for trading bots
client = Client(
    market_cache_ttl_seconds=10,       # 10 seconds
    quote_token_cache_ttl_seconds=60   # 1 minute
)

Next Steps

• Order - Understanding market and limit orders

• Gas Operations - When you need BNB for gas

• Quick Start Guide - Your first API calls