prisma-nestjs-graphql

Generate object types, inputs, args, etc. from prisma schema file for usage with @nestjs/graphql module.

Features

• Generates only necessary imports
• Combines zoo of nested/nullable filters
• Does not generate resolvers, since it's application specific

Install

npm install --save-dev prisma-nestjs-graphql

Usage

1. Add new generator section to schema.prisma file

generator nestgraphql {
    provider = "node node_modules/prisma-nestjs-graphql"
    output = "../src/@generated/prisma-nestjs-graphql"
}

2. Run prisma generate

npx prisma generate

Generator options

output

Output folder relative to this schema file
Type: string

outputFilePattern

File path and name pattern
Type: string
Default: {model}/{name}.{type}.ts
Possible tokens:

• {model} Model name in dashed case or 'prisma' if unknown
• {name} Dashed-case name of model/input/arg without suffix
• {type} Short type name (model, input, args, output)
• {plural.type} Plural short type name (models, inputs, enums)

tsConfigFilePath

Path to tsconfig.json
Type: string
Default: tsconfig.json

combineScalarFilters

Combine nested/nullable scalar filters to single
Type: boolean
Default: false

noAtomicOperations

Remove input types for atomic operations
Type: boolean
Default: false

reExport

Create index.ts file with re-export
Type: enum
Values:
None Default, create nothing
Directories Create index file in all root directories
Single Create single index file in output directory
All Create index file in all root directories and in output directory

Example configuration:

generator nestgraphql {
    provider = "node node_modules/prisma-nestjs-graphql"
    output = "../src/@generated/prisma-nestjs-graphql"
    reExport = Directories
}

emitSingle

Generate single file with merged classes and enums.
Type: boolean
Default: false

emitCompiled

Emit compiled JavaScript and definitions instead of TypeScript sources, files will be compiled with emitDecoratorMetadata:false, because there is a problem with temporal dead zone when generating merged file.
Type: boolean
Default: false

types_*

Map prisma scalar types in flatten style

• types_{type}_fieldType TypeScript field type name
• types_{type}_fieldModule Module to import
• types_{type}_graphqlType GraphQL type name
• types_{type}_graphqlModule Module to import

Where {type} is prisma type in schema

Example (Decimal):

types_Decimal_fieldType = "Decimal"
types_Decimal_fieldModule = "decimal.js"
types_Decimal_graphqlType = "GraphQLDecimal"
types_Decimal_graphqlModule = "graphql-type-decimal"

Generates field:

import { GraphQLDecimal } from 'graphql-type-decimal';
import { Decimal } from 'decimal.js';
...
@Field(() => GraphQLDecimal)
field: Decimal;

Example (DateTime):

types_DateTime_fieldType = "Date"
types_DateTime_graphqlType = "GraphQLISODateTime"
types_DateTime_graphqlModule = "@nestjs/graphql"

Generated fields:

@Field(() => GraphQLISODateTime)
field: Date;

Field Settings

Special directives in triple slash comments for more precise code generation.

@HideField()

Removes field from GraphQL schema.
Alias: @TypeGraphQL.omit(output: true)

By default (without arguments) field will be decorated for hide only in output types (type in schema).
To hide input types add input: true.
Examples:

• @HideField() same as @HideField(output: true) or @HideField({ output: true })
• @HideField({ input: true, output: true })

model User {
    id String @id @default(cuid())
    /// @HideField()
    password String
    /// @HideField({ output: true, input: true })
    secret String
}

May generate classes:

@ObjectType()
export class User {
    @HideField()
    password: string;
    @HideField()
    secret: string;
}

@InputType()
export class UserCreateInput {
    @Field()
    password: string;
    @HideField()
    secret: string;
}

Custom Decorators

Applying custom decorators requires configuration of generator.

generator nestgraphql {
    fields_{Namespace}_from = "module specifier"
    fields_{Namespace}_input = true | false
    fields_{Namespace}_output = true | false
    fields_{Namespace}_defaultImport = "default import name" | true
    fields_{Namespace}_namespaceImport = "namespace import name"
}

Create configuration map in flatten style for {Namespace}.
Where {Namespace} is a namespace used in field triple slash comment.

fields_{Namespace}_from

Name of the module, which will be used in import (class-validator, graphql-scalars, etc.)
Type: string
Required: yes

fields_{Namespace}_input

Means that it will be applied on input types (classes decorated by InputType)
Type: boolean
Default: false

fields_{Namespace}_output

Means that it will be applied on output types (classes decorated by ObjectType)
Type: boolean
Default: false

fields_{Namespace}_defaultImport

Default import name, if module have no namespace.
Type: undefined | string | true
Default: undefined
If defined as true then import name will be same as {Namespace}

fields_{Namespace}_namespaceImport

Import all as this namespace from module
Type: undefined | string
Default: Equals to {Namespace}

Example:

generator nestgraphql {
    fields_Validator_from = "class-validator"
    fields_Validator_input = true
}

model User {
    id Int @id
    /// @Validator.MinLength(3)
    name String
}

May generate following class:

import { InputType, Field } from '@nestjs/graphql';
import * as Validator from 'class-validator';

@InputType()
export class UserCreateInput {
    @Field(() => String, { nullable: false })
    @Validator.MinLength(3)
    name!: string;
}

@FieldType()

Allow set custom type for field

model User {
    id Int @id
    /// @FieldType({ name: 'Scalars.GraphQLEmailAddress', from: 'graphql-scalars', input: true })
    email String
}

May generate following class:

import { InputType, Field } from '@nestjs/graphql';
import * as Scalars from 'graphql-scalars';

@InputType()
export class UserCreateInput {
    @Field(() => Scalars.GraphQLEmailAddress, { nullable: false })
    email!: string;
}

And following GraphQL schema:

scalar EmailAddress

input UserCreateInput {
    email: EmailAddress!
}

Same field type may be used in different models and it is not convenient to specify every time all options. There is a shortcut:

generator nestgraphql {
    fields_Scalars_from = "graphql-scalars"
    fields_Scalars_input = true
    fields_Scalars_output = true
}

model User {
    id Int @id
    /// @FieldType('Scalars.GraphQLEmailAddress')
    email String
}

The result will be the same. Scalars is the namespace here. Missing field options will merged from generator configuration.

Similar Projects

• https://github.com/wSedlacek/prisma-generators/tree/master/libs/nestjs
• https://github.com/EndyKaufman/typegraphql-prisma-nestjs
• https://github.com/MichalLytek/typegraphql-prisma

Resources

• Todo - unlight#2
• https://github.com/prisma/prisma/blob/master/src/packages/client/src/generation/TSClient/TSClient.ts
• https://ts-ast-viewer.com/
• https://github.com/unlight/nestjs-graphql-prisma-realworld-example-app
• https://www.prisma.io/docs/reference/tools-and-interfaces/prisma-schema/data-model
• JSON type for the code first approach - nestjs/graphql#111 (comment)
• https://github.com/paljs/prisma-tools/tree/master/packages/plugins
• https://github.com/wasp-lang/wasp