feat: support nullable primitives and relations

valentinpalkovic · Sep 24, 2020 · 0f8de59 · 0f8de59
1 parent a131dd1
commit 0f8de59
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Showing 2 changed files with 50 additions and 37 deletions.
diff --git a/src/generator/properties.ts b/src/generator/properties.ts
@@ -1,5 +1,4 @@
 import { DMMF } from '@prisma/generator-helper'
-import { JSONSchema7, JSONSchema7Definition } from 'json-schema'
 import { DEFINITIONS_ROOT } from './constants'
 import {
     assertNever,
@@ -9,7 +8,13 @@ import {
 } from './helpers'
 import { ModelMetaData, PropertyMap, PropertyMetaData } from './types'
 
-function getJSONSchemaScalar(fieldType: PrismaPrimitive): JSONSchema7['type'] {
+import type {
+    JSONSchema7,
+    JSONSchema7Definition,
+    JSONSchema7TypeName,
+} from 'json-schema'
+
+function getJSONSchemaScalar(fieldType: PrismaPrimitive): JSONSchema7TypeName {
     switch (fieldType) {
         case 'String':
             return 'string'
@@ -29,14 +34,17 @@ function getJSONSchemaScalar(fieldType: PrismaPrimitive): JSONSchema7['type'] {
 }
 
 function getJSONSchemaType(field: DMMF.Field): JSONSchema7['type'] {
-    const { isList } = field
-    return isScalarType(field) && !isList
-        ? getJSONSchemaScalar(field.type)
-        : field.isList
-        ? 'array'
-        : isEnumType(field)
-        ? 'string'
-        : 'object'
+    const { isList, isRequired } = field
+    const scalarFieldType =
+        isScalarType(field) && !isList
+            ? getJSONSchemaScalar(field.type)
+            : field.isList
+            ? 'array'
+            : isEnumType(field)
+            ? 'string'
+            : 'object'
+
+    return isRequired || isList ? scalarFieldType : [scalarFieldType, 'null']
 }
 
 function getFormatByDMMFType(fieldType: string): string | undefined {
@@ -48,14 +56,18 @@ function getFormatByDMMFType(fieldType: string): string | undefined {
     }
 }
 
-function getItemsByDMMFType(
-    field: DMMF.Field,
-): JSONSchema7Definition | undefined {
+function getJSONSchemaForPropertyReference(field: DMMF.Field): JSONSchema7 {
+    const notNullable = field.isRequired || field.isList
+    const ref = { $ref: `${DEFINITIONS_ROOT}${field.type}` }
+    return notNullable ? ref : { anyOf: [ref, { type: 'null' }] }
+}
+
+function getItemsByDMMFType(field: DMMF.Field): JSONSchema7['items'] {
     return (isScalarType(field) && !field.isList) || isEnumType(field)
         ? undefined
         : isScalarType(field) && field.isList
         ? { type: getJSONSchemaScalar(field.type) }
-        : { $ref: `${DEFINITIONS_ROOT}${field.type}` }
+        : getJSONSchemaForPropertyReference(field)
 }
 
 function isSingleReference(field: DMMF.Field) {
@@ -73,19 +85,12 @@ function getEnumListByDMMFType(modelMetaData: ModelMetaData) {
     }
 }
 
-function getJSONSchemaForPropertyReference(field: DMMF.Field) {
-    return {
-        $ref: `${DEFINITIONS_ROOT}${field.type}`,
-    }
-}
-
 export function getJSONSchemaProperty(modelMetaData: ModelMetaData) {
     return (field: DMMF.Field): PropertyMap => {
         const type = getJSONSchemaType(field)
         const format = getFormatByDMMFType(field.type)
         const items = getItemsByDMMFType(field)
         const enumList = getEnumListByDMMFType(modelMetaData)(field)
-        const isReference = isSingleReference(field)
 
         const definition: JSONSchema7Definition = {
             type,
@@ -100,7 +105,9 @@ export function getJSONSchemaProperty(modelMetaData: ModelMetaData) {
 
         return [
             field.name,
-            isReference ? getJSONSchemaForPropertyReference(field) : definition,
+            isSingleReference(field)
+                ? getJSONSchemaForPropertyReference(field)
+                : definition,
             propertyMetaData,
         ]
     }

diff --git a/src/tests/generator.test.ts b/src/tests/generator.test.ts
@@ -17,7 +17,7 @@ const datamodel = /* Prisma */ `
 		name        String?
 		successorId Int?
 		successor   User?    @relation("BlogOwnerHistory", fields: [successorId], references: [id])
-		predecessor User?    @relation("BlogOwnerHistory")
+		predecessor User     @relation("BlogOwnerHistory")
 		role        Role     @default(USER)
 		posts       Post[]
         keywords    String[]
@@ -45,7 +45,12 @@ describe('JSON Schema Generator', () => {
                 Post: {
                     properties: {
                         id: { type: 'integer' },
-                        user: { $ref: '#/definitions/User' },
+                        user: {
+                            anyOf: [
+                                { $ref: '#/definitions/User' },
+                                { type: 'null' },
+                            ],
+                        },
                     },
                     type: 'object',
                 },
@@ -55,26 +60,31 @@ describe('JSON Schema Generator', () => {
                         createdAt: { format: 'date-time', type: 'string' },
                         email: { type: 'string' },
                         id: { type: 'integer' },
-                        is18: { type: 'boolean' },
+                        is18: { type: ['boolean', 'null'] },
                         keywords: { items: { type: 'string' }, type: 'array' },
-                        name: { type: 'string' },
+                        name: { type: ['string', 'null'] },
                         posts: {
                             items: { $ref: '#/definitions/Post' },
                             type: 'array',
                         },
                         predecessor: { $ref: '#/definitions/User' },
                         role: { enum: ['USER', 'ADMIN'], type: 'string' },
-                        successor: { $ref: '#/definitions/User' },
-                        weight: { type: 'integer' },
+                        successor: {
+                            anyOf: [
+                                { $ref: '#/definitions/User' },
+                                { type: 'null' },
+                            ],
+                        },
+                        weight: { type: ['integer', 'null'] },
                     },
                     type: 'object',
                 },
             },
-            type: 'object',
             properties: {
-                user: { $ref: '#/definitions/User' },
                 post: { $ref: '#/definitions/Post' },
+                user: { $ref: '#/definitions/User' },
             },
+            type: 'object',
         })
     })
 
@@ -88,8 +98,7 @@ describe('JSON Schema Generator', () => {
             post: {
                 id: 0,
                 user: {
-                    id: 3,
-                    weight: 10,
+                    id: 100,
                 },
             },
             user: {
@@ -101,7 +110,7 @@ describe('JSON Schema Generator', () => {
                 },
                 is18: true,
                 keywords: ['prisma2', 'json-schema', 'generator'],
-                name: 'Jan Uwe',
+                name: null,
                 posts: [
                     {
                         id: 4,
@@ -114,10 +123,7 @@ describe('JSON Schema Generator', () => {
                     id: 10,
                     email: 'horst@wassermann.de',
                 },
-                successor: {
-                    id: 12,
-                    name: 'Niels Emmerich',
-                },
+                successor: null,
                 role: 'USER',
                 weight: 10,
             },