[CONF] Apache Sling > Sling Feature Flags support

[Bertrand Delacretaz (Confluence)]

Sling Feature Flags support Page edited by Bertrand Delacretaz Changes (3) See also https://issues.apache.org/jira/browse/SLING-3148 for the timeline/history of this. For now we have a basic prototype at http://svn.apache.org/repos/asf/sling/whiteboard/bdelacretaz/feature-flags/ that allows for checking if a named feature flag is active or not. This is the easy part. h1. What sets a feature flag As described by Roy Fielding on the Sling dev list (http://markmail.org/message/rueoiuacmft5fdet) {quote} Likewise, you should expect to have both a global setting for each flag and a per-user mask, and the person running the flip switch control panel needs to be able to choose from a) off for all users b) off for unassigned users c) proportional assignment to on (X out of N users, max M) d) logical (custom code) assignment to on e) on for unassigned users f) on for all users {quote} h1. Feature Flags use cases TBD {warning:title=Work in Progress} This is still experimental, work in progress, not final etc...just rough ideas for now. {warning} h2. Show/Hide Resources Make some Resources completely invisible in specific requests, based on feature flags. All descendant Resources of a hidden Resource are hidden as well. Need to be careful about caching. h2. Alter Resource rendering Can be achieved transparently by hiding rendering scripts and servlets. Need to be careful about caching. Might need to happen on the client as well as on the server, depending on the desired caching behavior. h2. Use variants of OSGi services A call to sling.getService("foo") in a rendering script, for example, can return different variants of the "foo" service depending on which feature flags are active. The usage value needs to be weighed against implementation difficulty... Full Content See also https://issues.apache.org/jira/browse/SLING-3148 for the timeline/history of this. For now we have a basic prototype at http://svn.apache.org/repos/asf/sling/whiteboard/bdelacretaz/feature-flags/ that allows for checking if a named feature flag is active or not. This is the easy part. What sets a feature flag As described by Roy Fielding on the Sling dev list (http://markmail.org/message/rueoiuacmft5fdet) Likewise, you should expect to have both a global setting for each flag and a per-user mask, and the person running the flip switch control panel needs to be able to choose from a) off for all users b) off for unassigned users c) proportional assignment to on (X out of N users, max M) d) logical (custom code) assignment to on e) on for unassigned users f) on for all users Feature Flags use cases Work in Progress This is still experimental, work in progress, not final etc...just rough ideas for now. Show/Hide Resources Make some Resources completely invisible in specific requests, based on feature flags. All descendant Resources of a hidden Resource are hidden as well. Need to be careful about caching. Alter Resource rendering Can be achieved transparently by hiding rendering scripts and servlets. Need to be careful about caching. Might need to happen on the client as well as on the server, depending on the desired caching behavior. Use variants of OSGi services A call to sling.getService("foo") in a rendering script, for example, can return different variants of the "foo" service depending on which feature flags are active. The usage value needs to be weighed against implementation difficulty... Stop watching space | Change email notification preferences View Online | View Changes | Add Comment