We already have an exclusion, for swagger-annotations, but in rest-tools module we have also swagger-core and swagger-models. Can be good investigate in possible problems or finally try to keep just one swagger library version in magnolia

If you add rest-tools as dependency in https://git.magnolia-cms.com/projects/PLATFORM/repos/ce/browse/magnolia-community-webapp/pom.xml then you get a compilation error:

collision: [swagger-core-2.0.9.jar, swagger-core-1.5.22.jar]
collision: [swagger-models-2.0.8.jar, swagger-models-1.5.22.jar]

We have two swagger dependency version in rest module.

[INFO] +- info.magnolia.bundle:magnolia-community-webapp:pom:6.2-SNAPSHOT:compile
[INFO] | +- info.magnolia.rest:magnolia-rest-services:jar:2.2-SNAPSHOT:compile
[INFO] | | - io.swagger:swagger-annotations:jar:1.5.22:compile
[INFO] | - info.magnolia.restclient:magnolia-rest-client:jar:2.0-SNAPSHOT:compile
[INFO] | +- io.swagger.core.v3:swagger-models:jar:2.0.8:compile
[INFO] | +- io.swagger.parser.v3:swagger-parser-core:jar:2.0.14:compile
[INFO] | - io.swagger.parser.v3:swagger-parser-v3:jar:2.0.14:compile
[INFO] | - io.swagger.core.v3:swagger-core:jar:2.0.9:compile
[INFO] | - io.swagger.core.v3:swagger-annotations:jar:2.0.9:compile
[INFO] - info.magnolia.rest:magnolia-rest-tools:jar:2.2-SNAPSHOT:compile
[INFO] +- io.swagger:swagger-jaxrs:jar:1.5.22:compile
[INFO] | - io.swagger:swagger-core:jar:1.5.22:compile
[INFO] - io.swagger:swagger-models:jar:1.5.22:compile

*Notice*
— Swaggers version in BOM —
<swaggerVersion>1.5.22</swaggerVersion>
<swagger-core-version>2.0.8</swagger-core-version>
<swagger-parser-version>2.0.14</swagger-parser-version>

– compile in Dx-core bundle –
swagger-annotations-1.5.22.jar
swagger-annotations-2.0.9.jar
swagger-core-2.0.9.jar
swagger-models-2.0.8.jar
swagger-parser-core-2.0.14.jar
swagger-parser-v3-2.0.14.jar

Latest note: 

Due to the Swagger upgrading ticket BUILD-374, Magnolia Rest Tool module, whose codebase is bases on the Swagger API 1.5.x, will not be recommended for bundling in any Magnolia project to prevent libraries confliction (Swagger 1.5.x and Swagger 2.x), therefore the Rest Tool Module will be quarantined, Swagger version for this module will not be declared in BOMS.