PgFlow.Flow.Step (PgFlow v0.1.0)

Represents a single step in a flow definition.

A step is the basic unit of work in a PgFlow workflow. Each step has:

A unique slug identifier
A type (:single or :map)
Optional dependencies on other steps
Optional retry configuration (max_attempts, base_delay, timeout)
Optional start delay

Step Types

:single - Executes once with the flow's input data
:map - Executes multiple times, once for each item in an array from a dependency

Examples

# Simple step with no dependencies
%PgFlow.Flow.Step{
  slug: :fetch_user,
  step_type: :single
}

# Step with dependencies and custom retry settings
%PgFlow.Flow.Step{
  slug: :send_email,
  step_type: :single,
  depends_on: [:fetch_user, :prepare_template],
  max_attempts: 5,
  base_delay: 2000
}

# Map step that processes an array
%PgFlow.Flow.Step{
  slug: :process_items,
  step_type: :map,
  depends_on: [:fetch_items]
}

Summary

Types

step_type()

t()

Functions

from_tuple(slug)

Converts a step tuple from the DSL into a Step struct.

slug_to_string(slug)

Converts a step slug (atom) to a string for database storage.

Types

step_type()

@type step_type() :: :single | :map

t()

@type t() :: %PgFlow.Flow.Step{
  base_delay: pos_integer() | nil,
  depends_on: [atom()],
  max_attempts: pos_integer() | nil,
  slug: atom(),
  start_delay: pos_integer() | nil,
  step_type: step_type(),
  timeout: pos_integer() | nil
}

Functions

from_tuple(slug)

@spec from_tuple(atom() | {atom(), keyword()}) :: t()

Converts a step tuple from the DSL into a Step struct.

Accepts tuples in the format:

{name, opts} - Step with options
name - Step with just a slug (converted to tuple internally)

Options

:depends_on - List of step slugs this step depends on (default: [])
:step_type - Either :single or :map (default: :single)
:max_attempts - Maximum retry attempts (default: flow default)
:base_delay - Base delay in milliseconds for exponential backoff (default: flow default)
:timeout - Timeout in milliseconds (default: flow default)
:start_delay - Delay in milliseconds before starting (default: nil)

Examples

iex> PgFlow.Flow.Step.from_tuple(:fetch_user)
%PgFlow.Flow.Step{slug: :fetch_user, step_type: :single, depends_on: []}

iex> PgFlow.Flow.Step.from_tuple({:send_email, depends_on: [:fetch_user]})
%PgFlow.Flow.Step{
  slug: :send_email,
  step_type: :single,
  depends_on: [:fetch_user]
}

iex> PgFlow.Flow.Step.from_tuple({:process_items, step_type: :map, depends_on: [:fetch_items]})
%PgFlow.Flow.Step{
  slug: :process_items,
  step_type: :map,
  depends_on: [:fetch_items]
}

slug_to_string(slug)

@spec slug_to_string(atom()) :: String.t()

Converts a step slug (atom) to a string for database storage.

Examples

iex> PgFlow.Flow.Step.slug_to_string(:fetch_user)
"fetch_user"

iex> PgFlow.Flow.Step.slug_to_string(:send_email)
"send_email"