Add support for Spring Boot multi-document properties files

Spring Boot 2.4 will add support for multi-document .properties files. These behave in a similar way to multi-document YAML files and allow the user to split a physical .properties file into multiple independent logical documents. With properties #--- is used as the separator. The reference documentation has an updated section that covers the new syntax.

The new format may cause a few problem with the IDE editor. Specifically, you can get errors about duplicate keys. It would be nice if the IDE could treat each logical section as a different document and not present those warnings. If you’re interested in some Java code that parses the new format, you can look at OriginTrackedPropertiesLoader.java from the Spring Boot codebase.

[kdvolder]

I’ve not seen any problems with the YAML editor. The YAML spec has always supported multiple documents so you probably already deal with them.

Correct.

Yeah, there’s also support for importing configs using spring.config.import. …

Sounds interesting. I have to admit I didn’t fully understand what you are suggesting / have in mind. But it sounds like if we discussed a bit… we could come up with something interesting to implement 😃. It would be great if you create a ticket for these kinds of enhancements.

Also thanks Phil for explaining some of the reasoning behind the decision. I understand it is a tradeof, naturally I was more concerned about the tooling impact and not as in tune with other considerations. All in all I think the tooling impact won’t be as bad. So I agree you probably made the right decision. My initial misgivings were overblown since I verified already that neither vanilla Eclipse nor vscode produces warnings about duplicate keys. So it’s just coming from STS and therefore it is under our control.

Step 1 would be a simple fix to just disable those warnings when we detect the document marker is present. That would be a trivial fix. But it wouldn’t be ideal.

Step 2 would be to make the editor truly aware of it’s multi-document stucture (i.e as in the yaml editor). This is likely a bit more involved. I haven’t a good idea yet how much work it would/will be and how important it is, but it should be feasible.

[spring-projects-issues]

(comment in Pivotal Tracker added by Nieraj Singh:)

Multi-doc support in properties file seems to work. See attached screenshot