A long poll notification service

We want web pages to update when the thing they are viewing changes. This offers a nicer feel and reduces the chance of in-flight collisions with very stale data.

Contact: Julian Edwards
On Launchpad: https://bugs.launchpad.net/launchpad-project/+bugs?field.tag=longpoll

As a User
I want Pages to show current information$FEATURE
so that I'm not looking at stale information

Rationale

We are bringing in rabbit to perform backend tasks more rapidly. In order to tell users that they have completed we need to signal the browser that things have changed.

Stakeholders

Technical Architect

Constraints and Requirements

Must

• Meet the new service requirements.

• Permit a page that a user is looking at to get notified of changes so that users can be shown them. E.g. new messages on a bug.

Nice to have

Must not

• Must not involve a new domain.

Out of scope

Subfeatures

Success

How will we know when we are done?

When a page updates just-in-time when changes are made, without polling or requiring users to refresh.

I'd argue that this isn't done-done until it's being used for two different pages. -- jml, 2011-06-24

How will we measure how well we have done?

Thoughts?

• Merge proposals (jobs more generically?) could be a good place to start -- jml, 2011-06-24