# `context`

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_(no submodules)_
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## Purpose

The `context` module owns the Hono `ContextVariableMap` declaration-merge
augmentation applied by `@suaveplan/api-plugin-campaigns`. Importing the
module for its side effects (which the package root barrel does
automatically) adds the typed slots the plugin's route handlers read with
`c.get(...)`, eliminating the `as any` casts that pile up in untyped Hono
middleware chains.

In Chunk A the only slot the plugin commits to is `eventBus`, because
that is the only context entry the no-op `onInit` placeholder would set if
it had a body. Chunks B and C will extend the declaration with the
repository handles (`campaignRepository`, `campaignSuppressionStore`,
`deliveryEventStore`) once those classes exist; consumers do not need to
re-import this module to pick the extensions up.

## Features

- Pure declaration-merge — zero runtime cost, zero bundle size.
- Re-exports an empty value (`export {}`) so the module participates in
  ES-module side-effect ordering without polluting the consumer's
  namespace.
- Slot type drawn from `@suaveplan/types` so the augmentation does not
  drag in the api-plugin-campaigns implementation surface.

## Usage: Basic

```ts
import { Hono } from "hono";
import "@suaveplan/api-plugin-campaigns"; // also pulls this module via the root barrel

const app = new Hono();
app.get("/", (c) => {
    const bus = c.get("eventBus");
    bus.emit("campaign.read", { id: "x" });
    return c.text("ok");
});
```

## Usage: Advanced

```ts
import "@suaveplan/api-plugin-campaigns/plugin/plugin"; // ensures the augmentation
import type { ContextVariableMap } from "hono";

type EventBus = ContextVariableMap["eventBus"];
```

## API Reference

- Adds `eventBus: EventBusLike` to Hono `ContextVariableMap`.
- No runtime exports.

## Implementation Notes

Module augmentations must live in a file with at least one `export`
statement to be picked up as a module rather than a script. The empty
`export {}` at the bottom is the standard idiom; removing it would
silently demote the file to a script and the `declare module "hono"`
block would stop applying.

Chunks B and C augment the same `ContextVariableMap` interface from
their own context modules, relying on TypeScript declaration merging to
union the slots together. That means agents working on later chunks
never edit this file — they add new files with their own
`declare module "hono"` blocks.