Feature flags on the graph

A feature flag in a chant workspace is a record that names a member, the build parameter of that member it sets, an owner, the work item it hides and a value per environment (chant’s guide). Turning one on is a reviewed commit that changes the record, and the release cut from that commit carries the new value through the environment’s gate. behold shows where each flag stands and never changes one.

The Flags tab

When behold serves a declared workspace, the panel has a Flags tab. It reads the flags from chant when you open it. Each flag shows:

• its member and id, web/new-checkout, with the record’s path on hover;
• param newCheckout · owner alice · work W-002 (in-progress);
• its value in each environment, in promotion order: staging on, prod off. An environment the record leaves out reads unset, and builds with the parameter’s default.

A flag the stale-flag lint reports (chant workspace check, WSP118) says due for removal (WSP118) after its name. Hover for the work item’s decisions: every one is confirmed, so the record and the parameter can go.

On the graph

Pick an environment under on the graph in. Every card of a flagged member gets a tag under it with the flag’s value there: new-checkout: on in green, new-checkout: off in grey, a value that is not true or false in blue. A member with several flags reads 2 flags: 1 on. A stale flag adds stale to the tag, in red. The tag’s tooltip lists each flag.

Why every card of the member

chant does not say which resources read a build parameter: the graph carries no parameter reads. So a flag marks every card of its member, and the tab says so.

Turn off the marks removes the tags and keeps the tab. Click a card to see its member’s flags in the inspect pane.

Turning a flag on

There is no toggle. A change to a flag is previewed as a change set:

• When a release that moves the flag’s parameter waits at an environment’s gate, the flag says so, newCheckout false to true waits at gate web/release/promote in staging, with a change set 05c8b35bc9a3 link. Click it to draw that change set on the graph, as the Trunk tab’s link does. A release’s entry is the component, web, which is no node of the graph, so the Change set tab lists it under not on the graph.
• Where the flag is off and nothing waits, the tab shows the lines that turn it on: a chant workspace records amend of the record’s values, and the git commit of the record. Once that commit is green, a release cut from it and promoted to the environment waits at the environment’s gate, and its change set opens from here.

What it reads

chant command	What the tab takes from it
chant workspace status <env> --json	each member’s featureFlags, the promotion order, and in each environment the gates waiting there with the change set they bind
chant change-set show <digest> --member <member> --json	for a waiting gate of a flagged member, the entries whose param:<name> attribute moves the flag’s parameter

featureFlags is new in chant 0.124.29. On an older chant the tab says Feature flags needs chant 0.124.29 or newer with the project’s version, the graph draws no flag marks, and the rest of behold works. behold doctor lists the read with its floor.