[SLING-7768] Add String Interpolation support to /etc/map

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Resource Resolver 1.7.0
• Component/s: ResourceResolver
• Environment: Sling 11-SNAPSHOT, JDK 1.8
• Assignee: Andreas Schaefer
• Reporter: Andreas Schaefer
• Created: 06/Jul/18 20:14
• Updated: 11/Nov/20 19:03
• Resolved: 28/Jan/20 22:48

Description

Having worked on migrations of a Sling derivate Ruben & I ran into issues where the /etc/map would map to production instead of testing environment.
Many big customer have extensive /etc/maps and also many different environments like dev, qa, staging, prod etc.
It would be great to have a tool where for example items like the host name or external links in /etc/map could be configured outside so that just one entry has to adjusted rather than creating a full copy of the /etc/map tree.
 
Example:
 
/etc/map/http/{{phv.fq.host.name}}.8080
 
Placeholder provides:
DEV: phv.fq.host.name=localhost
QA: phv.fq.host.name=qa.author.acme.com
STAGING: phv.fq.host.name=staging.author.acme.com
PROD: phv.fq.host.name=acme.com
 
At runtime these are the resolved values:
DEV: http/localhost.8080
QA: http/qa.author.acme.com.8080
STAGING: http/staging.author.acme.com.8080
PROD: http/acme.com.8080
 
Not only does that make it easier and faster to create new test environments but it also cuts down on the chance of copy-n-paste errors.
 
I have a working POC with an PlaceholderProvider OSGi service and an enhanced MapEntries that resolved any placeholders if found.
 
Attached are 3 screenshots:
1. OSGi Placeholder Provider Configuration
2. /etc/map (Composum)
3. Result of http://andreass.local:8080/ call

Issue Links

• is related to: SLING-9898 Support interpolation in Context-Aware Configuration
• is related to: SLING-9727 sling-mock: Make compatible with o.a.s.resourceresolver 1.7.0