velobase-billing 0.2.2

Velobase Billing SDK for Python

velobase-billing

Official Velobase Billing SDK for Python.

• Synchronous and asynchronous clients
• Type-safe with Pydantic v2 models and py.typed support
• Automatic retries with exponential backoff
• Python 3.9+

Installation

pip install velobase-billing

Quick Start

import uuid
from velobase_billing import Velobase

vb = Velobase(api_key="vb_live_xxx")

# 1. Deposit credits to a customer (creates the customer if new)
deposit = vb.customers.deposit(customer_id="user_123", amount=1000)

# 2. Check balance
customer = vb.customers.get("user_123")
print(customer.balance.available)  # 1000.0

# 3. Generate transaction_id once and persist before freezing
transaction_id = f"user_123_{uuid.uuid4().hex}"

# 4. Freeze credits before doing work
freeze = vb.billing.freeze(
    customer_id="user_123",
    amount=50,
    transaction_id=transaction_id,
)

# 5a. Job succeeded — consume (supports partial)
consume = vb.billing.consume(
    transaction_id=transaction_id,
    actual_amount=32,  # only charge 32, return 18
)

# 5b. Or if the job failed — unfreeze to return all
unfreeze = vb.billing.unfreeze(transaction_id=transaction_id)

How It Works

Velobase Billing uses a freeze-then-consume pattern to safely manage credits:

deposit -> freeze -> consume   (normal flow)
                  -> unfreeze  (failure/cancellation)

It also supports a direct deduct pattern for immediate deduction without freezing:

deposit -> deduct  (immediate deduction)

1. Deposit — Add integer credits to a customer's wallet. Creates the customer automatically on first deposit. Supports wallet/source for balance categories, and starts_at/expires_at for time-limited credits. credit_type is kept only as a deprecated alias for wallet.
2. Freeze — Pre-authorize an amount before performing work. The frozen credits are deducted from available but not yet used. Each freeze is identified by a unique transaction_id you provide. Supports credit_types to freeze from specific credit categories.
3. Consume — After the work is done, settle the frozen amount. You can pass actual_amount to charge less than what was frozen; the difference is automatically returned.
4. Unfreeze — If the work fails or is cancelled, release the full frozen amount back to the customer.
5. Deduct — Directly deduct credits from a customer without freezing first. Useful for immediate charges. Supports credit_types to deduct from specific credit categories.
6. Ledger — Query a customer's transaction history with filtering and cursor-based pagination.

All write operations are idempotent — repeating the same transaction_id (freeze/consume/unfreeze/deduct) or idempotency_key (deposit) returns the original result without double-charging.

Async Usage

Every method is available in an async version via AsyncVelobase:

from velobase_billing import AsyncVelobase

async def main():
    vb = AsyncVelobase(api_key="vb_live_xxx")

    deposit = await vb.customers.deposit(customer_id="user_123", amount=1000)
    customer = await vb.customers.get("user_123")
    print(customer.balance.available)

    await vb.close()

Context Manager

Both clients support context managers to ensure the underlying HTTP connection is closed:

# Sync
with Velobase(api_key="vb_live_xxx") as vb:
    customer = vb.customers.get("user_123")

# Async
async with AsyncVelobase(api_key="vb_live_xxx") as vb:
    customer = await vb.customers.get("user_123")

Configuration

vb = Velobase(
    api_key="vb_live_xxx",               # Required. Your Velobase API key.
    base_url="https://api.velobase.io",   # Optional. Override the API endpoint.
    timeout=30.0,                         # Optional. Request timeout in seconds (default: 30).
    max_retries=2,                        # Optional. Retry count on 5xx/network errors (default: 2).
)

Usage Examples

Deposit with idempotency

# Safe to retry — the second call returns the same result without double-charging
result = vb.customers.deposit(
    customer_id="user_123",
    amount=500,
    idempotency_key="order_abc_payment",
    description="Purchase of 500 credits",
)

print(result.added_amount)         # 500.0
print(result.is_idempotent_replay) # False on first call, True on retries

Deposit with wallet and expiry

result = vb.customers.deposit(
    customer_id="user_123",
    amount=1000,
    wallet="bonus",
    source="annual_campaign",
    starts_at="2025-01-01T00:00:00Z",
    expires_at="2025-12-31T23:59:59Z",
    description="Annual bonus credits",
)
print(result.wallet)        # "bonus"
print(result.source)        # "annual_campaign"
print(result.starts_at)     # "2025-01-01T00:00:00.000Z"
print(result.expires_at)    # "2025-12-31T23:59:59.000Z"

Deposit with customer metadata

result = vb.customers.deposit(
    customer_id="user_123",
    amount=1000,
    name="Alice",
    email="[e-mail]",
    metadata={"plan": "pro", "source": "stripe"},
)

Full billing flow (freeze-then-consume)

CUSTOMER = "user_123"
JOB_ID = "video_gen_001"

# Check balance before starting
before = vb.customers.get(CUSTOMER)
print(f"Available: {before.balance.available}")

# Freeze the estimated cost
vb.billing.freeze(
    customer_id=CUSTOMER,
    amount=100,
    transaction_id=JOB_ID,
    business_type="TASK",
    description="1080p video, ~60s",
)

# ... do the work ...

# Settle with the actual cost (partial consumption)
result = vb.billing.consume(
    transaction_id=JOB_ID,
    actual_amount=73,
)
print(f"Charged: {result.consumed_amount}")   # 73.0
print(f"Returned: {result.returned_amount}")  # 27.0

# Verify final balance
after = vb.customers.get(CUSTOMER)
print(f"Available: {after.balance.available}")

Direct deduct (without freezing)

CUSTOMER = "user_123"
TXN_ID = "api_call_001"

result = vb.billing.deduct(
    customer_id=CUSTOMER,
    amount=5,
    transaction_id=TXN_ID,
    business_type="TASK",
    description="API call charge",
)
print(f"Deducted: {result.deducted_amount}")  # 5.0
print(f"At: {result.deducted_at}")

Freeze with credit_types filter

# Only freeze from specific credit categories
freeze = vb.billing.freeze(
    customer_id="user_123",
    amount=50,
    transaction_id="job_abc",
    credit_types=["BONUS", "DEFAULT"],
)

Query transaction ledger

# List all ledger entries (default limit=20)
ledger = vb.customers.ledger("user_123")
for entry in ledger.items:
    print(entry.operation_type, entry.amount, entry.credit_type, entry.created_at)

print(f"Total: {ledger.total_count}")

# Filter by operation type
grants = vb.customers.ledger("user_123", operation_type="GRANT")

# Filter by transaction_id
txn_entries = vb.customers.ledger("user_123", transaction_id="job_abc")

# Paginate with cursor
page1 = vb.customers.ledger("user_123", limit=10)
if page1.has_more:
    page2 = vb.customers.ledger("user_123", limit=10, cursor=page1.next_cursor)

Customer balance structure

customer = vb.customers.get("user_123")

# Wallets are keyed by wallet/category name.
default_wallet = customer.wallets["default"]
default_wallet.total      # total deposited
default_wallet.used       # total consumed
default_wallet.frozen     # currently frozen (pending)
default_wallet.available  # total - used - frozen

# Sources inside each wallet preserve validity windows.
for source in default_wallet.sources:
    print(source.source)      # "default", "stripe_checkout", etc.
    print(source.available)
    print(source.starts_at)   # None or ISO date string
    print(source.expires_at)  # None or ISO date string

# Compatibility: customer.balance and customer.accounts are still available as
# derived views for older Python code.
customer.balance.available
customer.accounts[0].credit_type

API Reference

vb.customers.deposit(...) -> DepositResponse

Deposit credits. Creates the customer if they don't exist.

Parameter	Type	Required	Description
customer_id	str	Yes	Your unique customer identifier
amount	int	Yes	Integer credits to deposit (must be > 0)
wallet	str	No	Wallet/category to credit. Defaults to "default" on server.
source	str	No	Optional source label for this grant. Defaults to "default" on server.
credit_type	str	No	Deprecated alias for wallet, kept for compatibility.
starts_at	str	No	ISO datetime string. When the credits become active.
expires_at	str	No	ISO datetime string. When the credits expire. Must be after starts_at.
idempotency_key	str	No	Prevents duplicate deposits on retry
name	str	No	Customer display name
email	str	No	Customer email
metadata	dict	No	Arbitrary key-value metadata
description	str	No	Description for the deposit

Returns: DepositResponse with fields customer_id, account_id, wallet, source, total_amount, added_amount, starts_at, expires_at, record_id, is_idempotent_replay

vb.customers.get(customer_id) -> CustomerResponse

Retrieve a customer's balance and account details.

Returns: CustomerResponse with fields id, name, email, metadata, balance, accounts, created_at

vb.customers.ledger(customer_id, ...) -> LedgerResponse

Query a customer's transaction history with filtering and cursor-based pagination.

Parameter	Type	Required	Description
customer_id	str	Yes	Customer identifier
limit	int	No	Page size (1–100, default 20)
cursor	str	No	Cursor from a previous next_cursor for pagination
operation_type	str	No	Filter by operation type: FREEZE, CONSUME, UNFREEZE, GRANT, EXPIRE
transaction_id	str	No	Filter by transaction ID

Returns: LedgerResponse with fields items (list of LedgerEntry), total_count, has_more, next_cursor

Each LedgerEntry has: id, operation_type, amount, wallet, source, credit_type (legacy alias for wallet), transaction_id, business_type, description, account_id, status, created_at

vb.billing.freeze(...) -> FreezeResponse

Freeze credits before performing work.

Parameter	Type	Required	Description
customer_id	str	Yes	Customer identifier
amount	float	Yes	Amount to freeze (must be > 0)
transaction_id	str	Yes	Your unique ID for this operation (idempotency key)
credit_types	list[str]	No	Restrict freeze to specific credit categories
business_type	BusinessType	No	Business category. See business_type for accepted values.
description	str	No	Human-readable description

Returns: FreezeResponse with fields transaction_id, frozen_amount, freeze_details, is_idempotent_replay

vb.billing.consume(...) -> ConsumeResponse

Settle a frozen amount. Supports partial consumption.

Parameter	Type	Required	Description
transaction_id	str	Yes	The transaction_id from the freeze
actual_amount	float	No	Actual amount to charge. Defaults to full frozen amount.

Returns: ConsumeResponse with fields transaction_id, consumed_amount, returned_amount, consume_details, consumed_at, is_idempotent_replay

vb.billing.unfreeze(...) -> UnfreezeResponse

Release a frozen amount back to the customer.

Parameter	Type	Required	Description
transaction_id	str	Yes	The transaction_id from the freeze

Returns: UnfreezeResponse with fields transaction_id, unfrozen_amount, unfreeze_details, unfrozen_at, is_idempotent_replay

vb.billing.deduct(...) -> DeductResponse

Directly deduct credits without freezing first. Useful for immediate charges.

Parameter	Type	Required	Description
customer_id	str	Yes	Customer identifier
amount	float	Yes	Amount to deduct (must be > 0)
transaction_id	str	Yes	Your unique ID for this operation (idempotency key)
credit_types	list[str]	No	Restrict deduction to specific credit categories
business_type	BusinessType	No	Business category. See business_type for accepted values.
description	str	No	Human-readable description

Returns: DeductResponse with fields transaction_id, deducted_amount, deduct_details, deducted_at, is_idempotent_replay

transaction_id

transaction_id uniquely identifies one billing operation (freeze → consume/unfreeze cycle, or a single deduct) and acts as its idempotency key. The server uses it to prevent double-charging on retries.

Recommended format: {customer_id}_{uuid}

import uuid

# Generate once per billing operation, then persist it
transaction_id = f"{customer_id}_{uuid.uuid4().hex}"
# e.g. "user_123_a3f8c21d4e0b4a9f8c1d2e3f4a5b6c7d"

Rules:

• Generate once and store — create the UUID before calling freeze() or deduct(), save it to your database, and reuse the same value on retries
• Never regenerate at the call site — calling uuid.uuid4() inside freeze() produces a different ID on every attempt, breaking idempotency
• Unique within your project — two different billing operations must not share the same transaction_id

# Wrong — new UUID on every call, idempotency broken on retry
vb.billing.freeze(
    customer_id=customer_id,
    amount=50,
    transaction_id=f"{customer_id}_{uuid.uuid4().hex}",  # ❌ regenerated each time
)

# Correct — UUID generated once and persisted before calling freeze
transaction_id = db.get_or_create_transaction_id(operation_id, customer_id)
# e.g. db.get_or_create_transaction_id returns an existing ID or
#      stores f"{customer_id}_{uuid.uuid4().hex}" on first call

vb.billing.freeze(customer_id=customer_id, amount=50, transaction_id=transaction_id)
# Safe to retry — same transaction_id returns the original result
vb.billing.freeze(customer_id=customer_id, amount=50, transaction_id=transaction_id)

business_type

business_type is an optional parameter on freeze() and deduct() that categorises the billing operation for analytics and reconciliation. The SDK validates the value client-side and raises ValueError before sending any network request.

Accepted values:

Value	Description
"UNDEFINED"	Default / unclassified (server default when omitted)
"TASK"	Async task execution (e.g. video generation, image processing)
"ORDER"	One-time purchase or order fulfilment
"MEMBERSHIP"	Membership plan credit grant
"SUBSCRIPTION"	Subscription renewal credit grant
"FREE_TRIAL"	Free-trial credit grant
"ADMIN_GRANT"	Manually granted credits by an admin

from velobase_billing import Velobase, BusinessType

vb = Velobase(api_key="vb_live_xxx")

vb.billing.freeze(
    customer_id="user_123",
    amount=50,
    transaction_id="job_abc",
    business_type="TASK",         # ✅ IDE autocomplete + client-side validation
)

vb.billing.freeze(
    customer_id="user_123",
    amount=50,
    transaction_id="job_abc",
    business_type="INVALID_VAL",  # ❌ raises ValueError before making a network call
)

Error Handling

All API errors raise typed exceptions that inherit from VelobaseError:

from velobase_billing import VelobaseError, ValidationError, AuthenticationError, NotFoundError

try:
    vb.billing.freeze(
        customer_id="user_123",
        amount=999999,
        transaction_id="job_xyz",
    )
except ValidationError as e:
    # 400 — bad request or insufficient balance
    print(e.message)  # "insufficient balance"
except AuthenticationError as e:
    # 401 — invalid or missing API key
    pass
except NotFoundError as e:
    # 404 — customer not found
    pass
except VelobaseError as e:
    # catch-all for other API errors
    print(e.status, e.type, e.message)

Exception	HTTP Status	When
AuthenticationError	401	Invalid or missing API key
ValidationError	400	Bad params, insufficient balance
NotFoundError	404	Customer or resource not found
ConflictError	409	Conflicting operation
InternalError	500	Server-side error (auto-retried)

Retries

The SDK automatically retries on 5xx errors and network failures with exponential backoff (0.5s, 1s, 2s..., capped at 5s). Retries are safe because all Velobase write operations are idempotent.

4xx errors (validation, auth, not found) are never retried.

License

MIT