Create Function

Define your functions using the create_function decorator.

import inngest

@inngest_client.create_function(
    fn_id="import-product-images",
    trigger=inngest.TriggerEvent(event="shop/product.imported"),
)
async def fn(ctx: inngest.Context, step: inngest.Step):
    # Your function code

create_function

The create_function decorator accepts a configuration and wraps a plain function.

Configuration

  • Name
    batch_events
    Type
    Batch
    Required
    optional
    Description

    Configure how the function should consume batches of events (reference)

  • Name
    cancel
    Type
    Cancel
    Required
    optional
    Description

    Define an event that can be used to cancel a running or sleeping function (reference)

  • Name
    debounce
    Type
    Debounce
    Required
    optional
    Description

    Options to configure function debounce (reference)

  • Name
    fn_id
    Type
    str
    Required
    required
    Description

    A unique identifier for your function. This should not change between deploys.

  • Name
    name
    Type
    str
    Required
    optional
    Description

    A name for your function. If defined, this will be shown in the UI as a friendly display name instead of the ID.

  • Name
    on_failure
    Type
    function
    Required
    optional
    Description

    A function that will be called only when this Inngest function fails after all retries have been attempted (reference)

  • Name
    rate_limit
    Type
    RateLimit
    Required
    optional
    Description

    Options to configure how to rate limit function execution (reference)

  • Name
    retries
    Type
    int
    Required
    optional
    Description

    Configure the number of times the function will be retried from 0 to 20. Default: 4

  • Name
    throttle
    Type
    Throttle
    Required
    optional
    Description

    Options to configure how to throttle function execution

  • Name
    trigger
    Type
    TriggerEvent | TriggerCron | list[TriggerEvent | TriggerCron]
    Required
    required
    Description

    What should trigger the function to run. Either an event or a cron schedule. Use a list to specify multiple triggers.

Triggers

TriggerEvent

  • Name
    event
    Type
    str
    Required
    required
    Description

    The name of the event.

  • Name
    expression
    Type
    str
    Required
    optional
    Description

    A match expression using arbitrary event data. For example, event.data.user_id == async.data.user_id will only match events whose data.user_id matches the original trigger event's data.user_id.

TriggerCron

  • Name
    cron
    Type
    str
    Required
    required
    Description

    A unix-cron compatible schedule string.
    Optional timezone prefix, e.g. TZ=Europe/Paris 0 12 * * 5.

Multiple Triggers

Multiple triggers can be defined by setting the trigger option to a list of TriggerEvent or TriggerCron objects:

import inngest

@inngest_client.create_function(
    fn_id="import-product-images",
    trigger=[
      inngest.TriggerEvent(event="shop/product.imported"),
      inngest.TriggerEvent(event="shop/product.updated"),
    ],
)
async def fn(ctx: inngest.Context, step: inngest.Step):
    # Your function code

For more information, see the Multiple Triggers guide.

Handler

The handler is your code that runs whenever the trigger occurs. Every function handler receives a single object argument which can be deconstructed. The key arguments are event and step. Note, that scheduled functions that use a cron trigger will not receive an event argument.

@inngest_client.create_function(
    # Function options
)
async def fn(ctx: inngest.Context, step: inngest.Step):
    # Function code

ctx

  • Name
    attempt
    Type
    int
    Description

    The current zero-indexed attempt number for this function execution. The first attempt will be 0, the second 1, and so on. The attempt number is incremented every time the function throws an error and is retried.

  • Name
    event
    Type
    Event
    Description

    The event payload object that triggered the given function run. The event payload object will match what you send with inngest.send(). Below is an example event payload object:

    Properties
    • Name
      data
      Type
      dict[str, object]
      Description

      The event payload data.

    • Name
      id
      Type
      str
      Description
    • Name
      name
      Type
      str
      Description
    • Name
      ts
      Type
      int
      Description

      Time (Unix millis) the event was received by the Inngest server.

  • Name
    events
    Type
    list[Event]
    Description

    A list of event objects that's accessible when the batch_events is set on the function configuration.

    If batching is not configured, the list contains a single event payload matching the event argument.

  • Name
    logger
    Type
    logging.Logger
    Description

    A proxy object around either the logger you provided or the default logger.

  • Name
    run_id
    Type
    str
    Description

    The unique ID for the given function run. This can be useful for logging and looking up specific function runs in the Inngest dashboard.

step

The step object has a method for each kind of step in the Inngest platform.

If your function is async then its type is Step and you can use await to call its methods. If your function is not async then its type is SyncStep.

  • Name
    run
    Type
    Callable
    Description

    Docs

  • Name
    send_event
    Type
    Callable
    Description

    Docs

  • Name
    sleep
    Type
    Callable
    Description

    Docs

  • Name
    sleep_until
    Type
    Callable
    Description

    Docs

  • Name
    _experimental_parallel
    Type
    Callable
    Version
    0.2.0+
    Description

    Docs