Request and Response Types

class CreateBudgetRequest:
    """
    Request message for creating a budget.

    Attributes:
        parent (str): Required. Name of the billing account to create budget in.
            Format: billingAccounts/{billingAccountId}
        budget (Budget): Required. Budget to create
    """
    parent: str  # Format: billingAccounts/{billingAccountId}
    budget: Budget

# Response: Budget object (the created budget)

class GetBudgetRequest:
    """
    Request message for getting a budget.

    Attributes:
        name (str): Required. Name of budget to retrieve.
            Format: billingAccounts/{billingAccountId}/budgets/{budgetId}
    """
    name: str  # Format: billingAccounts/{billingAccountId}/budgets/{budgetId}

# Response: Budget object

class UpdateBudgetRequest:
    """
    Request message for updating a budget.

    Attributes:
        budget (Budget): Required. The updated budget object. Must contain
            a valid name field for identifying the budget to update
        update_mask (FieldMask): Optional. Indicates which budget fields
            should be updated. If not provided, all fields will be updated
    """
    budget: Budget
    update_mask: FieldMask

# Response: Budget object (the updated budget)

class DeleteBudgetRequest:
    """
    Request message for deleting a budget.

    Attributes:
        name (str): Required. Name of the budget to delete.
            Format: billingAccounts/{billingAccountId}/budgets/{budgetId}
    """
    name: str  # Format: billingAccounts/{billingAccountId}/budgets/{budgetId}

# Response: Empty (no content returned on successful deletion)

class ListBudgetsRequest:
    """
    Request message for listing budgets.

    Attributes:
        parent (str): Required. Name of billing account to list budgets for.
            Format: billingAccounts/{billingAccountId}
        scope (str): Optional. Set to projects/{projectId} to list budgets
            that are scoped to a specific project
        page_size (int): Optional. Requested page size. Maximum value is 100.
            If not specified, returns at most 50 budgets
        page_token (str): Optional. Page token for pagination. Pass the
            next_page_token from previous response to get next page
    """
    parent: str  # Format: billingAccounts/{billingAccountId}
    scope: str   # Optional: projects/{projectId}
    page_size: int  # Max 100, default ~50
    page_token: str

class ListBudgetsResponse:
    """
    Response message for listing budgets.

    Attributes:
        budgets (List[Budget]): List of budgets owned by the specified
            billing account
        next_page_token (str): Token to retrieve the next page of results.
            Empty if no more results exist
    """
    budgets: List[Budget]
    next_page_token: str

    @property
    def raw_page(self) -> ListBudgetsResponse:
        """
        Returns the raw page response (self).
        Required for pager compatibility.
        """
        return self

class FieldMask:
    """
    A field mask to specify which fields should be updated.

    Attributes:
        paths (List[str]): The set of field mask paths. Examples:
            - ["display_name"] - Update only display name
            - ["amount", "threshold_rules"] - Update amount and thresholds
            - ["budget_filter.projects"] - Update only filter projects
    """
    paths: List[str]

from google.cloud.billing import budgets

# Create request object
request = budgets.CreateBudgetRequest(
    parent="billingAccounts/123456-ABCDEF-789012",
    budget=budgets.Budget(
        display_name="Development Budget",
        amount=budgets.BudgetAmount(
            specified_amount={"currency_code": "USD", "units": 500}
        ),
        budget_filter=budgets.Filter(
            projects=["projects/dev-project"],
            calendar_period=budgets.CalendarPeriod.MONTH
        ),
        threshold_rules=[
            budgets.ThresholdRule(
                threshold_percent=0.8,
                spend_basis=budgets.ThresholdRule.Basis.CURRENT_SPEND
            )
        ]
    )
)

# Send request
client = budgets.BudgetServiceClient()
created_budget = client.create_budget(request=request)

# Or use keyword arguments directly
created_budget = client.create_budget(
    parent="billingAccounts/123456-ABCDEF-789012",
    budget=budget
)

from google.cloud.billing import budgets

# Create request object
request = budgets.GetBudgetRequest(
    name="billingAccounts/123456-ABCDEF-789012/budgets/budget-id-123"
)

# Send request
client = budgets.BudgetServiceClient()
budget = client.get_budget(request=request)

# Or use keyword arguments
budget = client.get_budget(
    name="billingAccounts/123456-ABCDEF-789012/budgets/budget-id-123"
)

from google.cloud.billing import budgets
from google.protobuf import field_mask_pb2

# Get existing budget first
client = budgets.BudgetServiceClient()
budget_name = "billingAccounts/123456-ABCDEF-789012/budgets/budget-id-123"
existing_budget = client.get_budget(name=budget_name)

# Modify only specific fields
existing_budget.display_name = "Updated Budget Name"
existing_budget.threshold_rules = [
    budgets.ThresholdRule(
        threshold_percent=0.75,  # Changed from 0.8 to 0.75
        spend_basis=budgets.ThresholdRule.Basis.CURRENT_SPEND
    )
]

# Create field mask to specify which fields to update
update_mask = field_mask_pb2.FieldMask(
    paths=["display_name", "threshold_rules"]
)

# Create update request
request = budgets.UpdateBudgetRequest(
    budget=existing_budget,
    update_mask=update_mask
)

# Send request
updated_budget = client.update_budget(request=request)

# Or use keyword arguments
updated_budget = client.update_budget(
    budget=existing_budget,
    update_mask=update_mask
)

from google.cloud.billing import budgets

# List all budgets for a billing account
request = budgets.ListBudgetsRequest(
    parent="billingAccounts/123456-ABCDEF-789012",
    page_size=10  # Get 10 budgets per page
)

client = budgets.BudgetServiceClient()
response = client.list_budgets(request=request)

# Process first page
for budget in response.budgets:
    print(f"Budget: {budget.display_name}")

# Get next page if available
if response.next_page_token:
    next_request = budgets.ListBudgetsRequest(
        parent="billingAccounts/123456-ABCDEF-789012",
        page_size=10,
        page_token=response.next_page_token
    )
    next_response = client.list_budgets(request=next_request)

# Or use the pager (recommended)
pager = client.list_budgets(
    parent="billingAccounts/123456-ABCDEF-789012"
)

# Iterate through all budgets automatically
for budget in pager:
    print(f"Budget: {budget.display_name}")

from google.cloud.billing import budgets

# List budgets scoped to a specific project
request = budgets.ListBudgetsRequest(
    parent="billingAccounts/123456-ABCDEF-789012",
    scope="projects/my-specific-project"
)

client = budgets.BudgetServiceClient()
response = client.list_budgets(request=request)

print(f"Found {len(response.budgets)} budgets for the project")
for budget in response.budgets:
    print(f"Project Budget: {budget.display_name}")

from google.cloud.billing import budgets

# Create delete request
request = budgets.DeleteBudgetRequest(
    name="billingAccounts/123456-ABCDEF-789012/budgets/budget-id-123"
)

# Send request (no response content on success)
client = budgets.BudgetServiceClient()
client.delete_budget(request=request)

# Or use keyword arguments
client.delete_budget(
    name="billingAccounts/123456-ABCDEF-789012/budgets/budget-id-123"
)

print("Budget deleted successfully")

from google.cloud.billing import budgets

client = budgets.BudgetServiceClient()
parent = "billingAccounts/123456-ABCDEF-789012"

# Create multiple budgets
budgets_to_create = [
    budgets.Budget(
        display_name=f"Project {i} Budget",
        amount=budgets.BudgetAmount(
            specified_amount={"currency_code": "USD", "units": 1000 * (i + 1)}
        ),
        budget_filter=budgets.Filter(
            projects=[f"projects/project-{i}"],
            calendar_period=budgets.CalendarPeriod.MONTH
        )
    )
    for i in range(3)
]

created_budgets = []
for budget in budgets_to_create:
    created_budget = client.create_budget(parent=parent, budget=budget)
    created_budgets.append(created_budget)
    print(f"Created: {created_budget.name}")

# List all budgets to verify
pager = client.list_budgets(parent=parent)
all_budgets = list(pager)
print(f"Total budgets: {len(all_budgets)}")

# Clean up - delete created budgets
for budget in created_budgets:
    client.delete_budget(name=budget.name)
    print(f"Deleted: {budget.name}")

from google.cloud.billing import budgets
from google.api_core import exceptions

client = budgets.BudgetServiceClient()

try:
    # Attempt to get a non-existent budget
    budget = client.get_budget(
        name="billingAccounts/123456/budgets/non-existent"
    )
except exceptions.NotFound:
    print("Budget not found")
except exceptions.PermissionDenied:
    print("Insufficient permissions to access budget")
except exceptions.InvalidArgument as e:
    print(f"Invalid request: {e}")
except exceptions.GoogleAPICallError as e:
    print(f"API call failed: {e}")

try:
    # Attempt to create budget with invalid parent
    client.create_budget(
        parent="invalid-parent-format",
        budget=budgets.Budget(display_name="Test")
    )
except exceptions.InvalidArgument as e:
    print(f"Invalid parent format: {e}")