Make adding directives to existing fields easier when schema stitching

[kbrandwijk]

When I use mergeSchemas for schema stitching, I often need to add a directive to a field (to specify cacheControl). However, I can't put the same field in two schemas, because it will give me an error if I do so. My workaround was going to be:

• get the first schema (makeRemoteExecutableSchema)
• call transformSchema on it to remove the existing field
• merge with the second schema that contains the new field definition

But in that case, the field no longer 'belongs' to the first schema, so it isn't resolved correctly without delegating it back to the original field, which doesn't work when I use transformSchema to remove it first.

It would be helpful if I could set a directive on the field in my second schema, @overwrite or something, that would make this easier for me to do. Because now my only workaround is to create a field with a new name in my second schema, then do the merge, and then remove the original field using transformSchema. I don't know why, but that way my delegate keeps working! And renaming a lot of fields like this isn't really a good solution...

[yaacovCR]

This maybe could be handled now with some custom fieldConfigMerger logic, https://www.graphql-tools.com/docs/stitch-type-merging

Needs to be explored....

[yaacovCR]

Actually I think easiest thing is to use mergeSchemas which should merge in directives...

Note that stitching function is now called stitchSchemas, so mergeSchemas just straight merges without wrapping or proxying

[ardatan]

I think @yaacovCR is right. Feel free to create a new issue if this is still relevant.