Allow for the file extensions used when scanning for schema definitions to be overridden via configuration properties

[jhinch-at-atlassian-com]

Currently, GraphQlAutoConfiguration hard codes the file extensions which will be searched when discovering schema definitions. This caused issues when trying to integrate spring-graphql into a project as we were using .graphql files to store GraphQL queries and .graphqls to store schema definitions. This caused the application context to blow up at runtime.

We worked around this problem by moving the queries and schemas into different directories, but having more control over this would be useful considering the directory to scan is already configurable.

[bclozel]

You're right, we should make that configurable.

@rstoyanchev with the upcoming client support, do you think we should change the defaults to consider only "*.graphqls", "*.gqls" for schema files and "*.graphql", "*.gql" for queries?

[rstoyanchev]

"*.graphqls", "*.gqls" sounds good as a default.

[busches]

This appears to be the behavior in 1.0.0-SNAPSHOT. Can we update the documentation to make this clear? https://docs.spring.io/spring-graphql/docs/1.0.0-SNAPSHOT/reference/html/#boot-graphql-schema I had to swap from schema.graphql to schema.graphqls before Spring would start.

[rstoyanchev]

Yes, I've updated the docs. Thanks, @busches!