descriptor

Custom directive descriptor helper.

See

Option customDirective.[directive].descriptor

directiveDescriptor()

function directiveDescriptor(
   directive, 
   type?, 
   descriptionTemplate?): string

Helper for rendering custom description from schema directive on type. This is an example on how to build a custom descriptor callback.

Parameters

• directive: GraphQLDirective

the schema directive to parse.

• type?: unknown

the schema type to be processed for generating a custom description.

• descriptionTemplate?: string

optional template literal-like string for rendering the description (see interpolate), if not present then the directive description will be used.

Returns

string

a custom description based on directive value.

Example

import { GraphQLDirective, GraphQLScalarType } from "graphql";
import { directiveDescriptor } from "@graphql-markdown/helpers/directives/descriptor";

const directive = new GraphQLDirective({
  name: "version",
  description: "Min version",
  locations: [],
  args: {
    major: { type: GraphQLInt, defaultValue: 0 },
    minor: { type: GraphQLInt, defaultValue: 0 },
    patch: { type: GraphQLInt, defaultValue: 0 },
  },
});

const type = new GraphQLScalarType<string>({
  name: "FooBar",
  astNode: {
    kind: Kind.SCALAR_TYPE_DEFINITION,
    name: { kind: Kind.NAME, value: "FooBar" },
    directives: [
      {
        kind: Kind.DIRECTIVE,
        name: { kind: Kind.NAME, value: "version" },
        arguments: [
          {
            kind: Kind.ARGUMENT,
            name: { kind: Kind.NAME, value: "major" },
            value: { kind: Kind.INT, value: "2" },
          },
          {
            kind: Kind.ARGUMENT,
            name: { kind: Kind.NAME, value: "minor" },
            value: { kind: Kind.INT, value: "1" },
          },
          {
            kind: Kind.ARGUMENT,
            name: { kind: Kind.NAME, value: "patch" },
            value: { kind: Kind.INT, value: "3" },
          },
        ],
      },
    ],
  },
});

directiveDescriptor(directive, type, "${description} is ${major}.${minor}.${patch}");
// Expected result: "Min version is 2.1.3"

directiveDescriptor(directive, type);
// Expected result: "Min version"

directiveDescriptor(directive, type, "Version should be at least ^${major}.${minor}.${patch}");
// Expected result: "Version should be at least ^2.1.3"

Defined in

directives/descriptor.ts:83