GeoGenius.Context (geo_genius v0.2.0)

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Runtime dependencies for one GeoGenius operation.

Summary

Types

t()

Functions

adapter(context, name)

The module serving one adapter role for this operation.

new(opts \\ [])

Builds a context from explicit options over package configuration.

Types

t()

@type t() :: %GeoGenius.Context{
  cache: module() | nil,
  command: module() | nil,
  downloader: module() | nil,
  notifier: module() | nil,
  prefix: String.t(),
  repo: module(),
  runner: module() | nil,
  store: module()
}

Functions

adapter(context, name)

@spec adapter(t(), atom()) :: module()

The module serving one adapter role for this operation.

A context built through new/1 carries its adapters. A context assembled as a struct literal carries nil, and falls back to the same resolution new/1 used, so a caller that built one by hand still gets a working adapter rather than a nil module and an UndefinedFunctionError several phases in.

:runner always routes through Runner.configured/1, even when this context already carries an explicit module for it: that is the only place an explicit runner is validated -- checked for Code.ensure_loaded?/1 and every GeoGenius.Runner callback -- and a lookup that returned early on a non-nil field would skip that check on the one path a host actually calls, Context.new(runner: SomeModule) |> Context.adapter(:runner). The other adapters have no such validation step, so they keep the cheap early return: a context already carrying one never spends a second lookup on it.

new(opts \\ [])

@spec new(keyword()) :: t()

Builds a context from explicit options over package configuration.

The application environment describes exactly one host. A VM serving several hosts passes :repo and :prefix on every call instead.

:runner carries only what opts explicitly gave -- never nil coalesced against config :geo_genius, :runner here, and never validated here. Both of those happen once, in Runner.configured/1, the only place they need to live: adapter/2 routes every :runner lookup through it below, whether this context ends up carrying an explicit module or nil.