---
title: "init(upstream:strategy:options:)"
framework: combine
role: symbol
role_heading: Initializer
path: "combine/publishers/collectbytime/init(upstream:strategy:options:)"
---

# init(upstream:strategy:options:)

Creates a publisher that buffers and periodically publishes its items.

## Declaration

```swift
init(upstream: Upstream, strategy: Publishers.TimeGroupingStrategy<Context>, options: Context.SchedulerOptions?)
```

## Parameters

- `upstream`: The publisher that this publisher receives elements from.
- `strategy`: The strategy with which to collect and publish elements.
- `options`: Scheduler options to use for the strategy.