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2.0.9

AppEnvironment

Package: flyte.app

Configure a long-running app environment for APIs, dashboards, or model servers.

Example:

app_env = flyte.app.AppEnvironment(
    name="my-api",
    image=flyte.Image.from_debian_base(python="3.12").with_pip_packages("fastapi", "uvicorn"),
    port=8080,
    scaling=flyte.app.Scaling(replicas=(1, 3)),
)

Parameters 

class AppEnvironment(
    name: str,
    depends_on: List[Environment],
    pod_template: Optional[Union[str, PodTemplate]],
    description: Optional[str],
    secrets: Optional[SecretRequest],
    env_vars: Optional[Dict[str, str]],
    resources: Optional[Resources],
    interruptible: bool,
    image: Union[str, Image, Literal['auto'], None],
    type: Optional[str],
    port: int | Port,
    args: *args,
    command: Optional[Union[List[str], str]],
    requires_auth: bool,
    scaling: Scaling,
    domain: Domain | None,
    links: List[Link],
    include: List[str],
    parameters: List[Parameter],
    cluster_pool: str,
    timeouts: Timeouts,
)
Parameter Type Description
name str Name of the app (required). Must be lowercase alphanumeric with hyphens. Inherited from Environment.
depends_on List[Environment] Dependencies on other environments (deployed together). Inherited from Environment.
pod_template Optional[Union[str, PodTemplate]]
description Optional[str]
secrets Optional[SecretRequest] Secrets to inject. Inherited from Environment.
env_vars Optional[Dict[str, str]] Environment variables. Inherited from Environment.
resources Optional[Resources] Compute resources (CPU, memory, GPU). Inherited from Environment.
interruptible bool
image Union[str, Image, Literal['auto'], None] Docker image for the environment. Inherited from Environment.
type Optional[str] App type identifier (e.g., "streamlit", "fastapi"). When set, the platform may apply framework-specific defaults.
port int | Port Port for the app server. Default 8080. Ports 8012, 8022, 8112, 9090, and 9091 are reserved and cannot be used. Can also be a Port object for advanced configuration.
args *args Arguments passed to the app process. Can be a list of strings or a single string. Used for script-based apps (e.g., Streamlit’s ["--server.port", "8080"]).
command Optional[Union[List[str], str]] Full command to run in the container. Alternative to args — use when you need to override the container’s entrypoint entirely.
requires_auth bool Whether the app endpoint requires authentication. Default True. Set to False for public endpoints.
scaling Scaling Scaling object controlling replicas and autoscaling behavior. Default is Scaling() (scale-to-zero, max 1 replica).
domain Domain | None Domain object for custom domain configuration.
links List[Link] List of Link objects for connecting to other environments.
include List[str] List of additional file paths to bundle with the app (e.g., utility modules, config files, data files).
parameters List[Parameter] List of Parameter objects for app inputs. Use RunOutput to connect app parameters to task outputs, or AppEndpoint to reference other app endpoints.
cluster_pool str Cluster pool for scheduling. Default "default".
timeouts Timeouts Timeouts object for startup/health check timeouts.

Properties

Property Type Description
endpoint None

Methods

Method Description
add_dependency() Add a dependency to the environment.
clone_with()
container_args()
container_cmd()
get_port()
on_shutdown() Decorator to define the shutdown function for the app environment.
on_startup() Decorator to define the startup function for the app environment.
server() Decorator to define the server function for the app environment.

add_dependency() 

def add_dependency(
    env: Environment,
)

Add a dependency to the environment.

Parameter Type Description
env Environment

clone_with() 

def clone_with(
    name: str,
    image: Optional[Union[str, Image, Literal['auto']]],
    resources: Optional[Resources],
    env_vars: Optional[dict[str, str]],
    secrets: Optional[SecretRequest],
    depends_on: Optional[List[Environment]],
    description: Optional[str],
    interruptible: Optional[bool],
    kwargs: **kwargs,
) -> AppEnvironment
Parameter Type Description
name str
image Optional[Union[str, Image, Literal['auto']]]
resources Optional[Resources]
env_vars Optional[dict[str, str]]
secrets Optional[SecretRequest]
depends_on Optional[List[Environment]]
description Optional[str]
interruptible Optional[bool]
kwargs **kwargs

container_args() 

def container_args(
    serialize_context: SerializationContext,
) -> List[str]
Parameter Type Description
serialize_context SerializationContext

container_cmd() 

def container_cmd(
    serialize_context: SerializationContext,
    parameter_overrides: list[Parameter] | None,
) -> List[str]
Parameter Type Description
serialize_context SerializationContext
parameter_overrides list[Parameter] | None

get_port() 

def get_port()

on_shutdown() 

def on_shutdown(
    fn: Callable[..., None],
) -> Callable[..., None]

Decorator to define the shutdown function for the app environment.

This function is called after the server function is called.

This decorated function can be a sync or async function, and accepts input parameters based on the Parameters defined in the AppEnvironment definition.

Parameter Type Description
fn Callable[..., None]

on_startup() 

def on_startup(
    fn: Callable[..., None],
) -> Callable[..., None]

Decorator to define the startup function for the app environment.

This function is called before the server function is called.

The decorated function can be a sync or async function, and accepts input parameters based on the Parameters defined in the AppEnvironment definition.

Parameter Type Description
fn Callable[..., None]

server() 

def server(
    fn: Callable[..., None],
) -> Callable[..., None]

Decorator to define the server function for the app environment.

This decorated function can be a sync or async function, and accepts input parameters based on the Parameters defined in the AppEnvironment definition.

Parameter Type Description
fn Callable[..., None]