Add validation rule that operation types exist

At a glance

• Identifier: #955
• Stage: RFC 3 / Accepted
• Champion: @benjaminjkraft
• Latest activity: Added to WG agenda on 2025-06-26
• Spec PR: https://github.com/graphql/graphql-spec/pull/955
• Related:
  • #1097
  • #947

Spec PR description

Right now the spec says that, for example, if the schema does not define a mutation root type, then the schema does not support mutations. But there's no validation rule for it, which means that many parsers (including graphql-js) treat a mutation as valid against such a schema. (Indeed, many end up considering any mutation as valid, since they don't know what type to validate the root selection set against.) This commit adds a validation rule to make the schema text explicit.

Slated for discussion at the June 2 2022 working group meeting. Replaces #947. See also graphql/graphql-js#3592.

Update October 2024: this PR has been refreshed including changes proposed in #1098 and Benjie's editorial edits.

Fixes #1097

Timeline

• Added to WG agenda on 2025-06-26
• Added to WG agenda on 2024-12-05
• Mentioned in WG notes on 2024-12-01
• 9 commits pushed on 2024-10-17:
  • benjie committed "Undo changes to Section 3"
  • benjie committed "Merge branch 'main' into operation-type-validation"
  • benjie committed "Editorial"
  • benjie committed "Merge remote-tracking branch 'Shane32/Shane32-patch-1' into operation…"
  • benjie committed "Move Shane's content"
  • benjie committed "More editorial"
  • benjie committed "More editorial"
  • benjie committed "Update spec/Section 5 -- Validation.md"
  • benjie committed "Update spec/Section 5 -- Validation.md"
• 2 commits pushed on 2024-10-04:
  • Shane32 committed "Merge branch 'main' into Shane32-patch-1"
  • Shane32 committed "Reformat"
• Commit pushed on 2024-06-04 by Shane32: Apply suggestions from code review
• 4 commits pushed on 2024-05-27:
  • Shane32 committed "Add 5.2.4 Operation Type Configuration"
  • Shane32 committed "Update spec/Section 5 -- Validation.md"
  • Shane32 committed "Update spec/Section 5 -- Validation.md"
  • Shane32 committed "Update spec/Section 5 -- Validation.md"
• 2 commits pushed on 2022-06-13:
  • benjaminjkraft committed "typofix"
  • benjaminjkraft committed "indentation"
• Added to WG agenda on 2022-06-02
• Spec PR created on 2022-06-01 by benjaminjkraft
• 2 commits pushed on 2022-06-01:
  • benjaminjkraft committed "Add validation rule that operation types exist"
  • benjaminjkraft committed "prettier"