P
Prisma•10mo ago
Nik

[ADVANCED] Prisma Extensions - dynamic typing

I'm trying to create a $allModels extension with proper typing and have been struggling. This is what I was able to cobble together: 
model: {
      $allModels:{
        async findOrCreate<T>(
          this: T,
          query: Prisma.Args<T, 'create'>['data']
        ):Promise< Prisma.Result<T, undefined, 'findFirstOrThrow'> >{
          const ctx = Prisma.getExtensionContext(this);
          let record = await (ctx as any).findFirst({where:query});
          if(!record)
            record = await (ctx as any).create({data:query});
          return record;
        },
      }
}
model: {
      $allModels:{
        async findOrCreate<T>(
          this: T,
          query: Prisma.Args<T, 'create'>['data']
        ):Promise< Prisma.Result<T, undefined, 'findFirstOrThrow'> >{
          const ctx = Prisma.getExtensionContext(this);
          let record = await (ctx as any).findFirst({where:query});
          if(!record)
            record = await (ctx as any).create({data:query});
          return record;
        },
      }
}
There are a few issues I want to resolve here: 1) There has to be some better typing for the ctx (or accessing the parent model). 2) I want to have an includes parameter, and return dynamic typing much like a regular .findFirst query. How can I achieve this? The only thing I can think of is that undefined Result generic which i can't seem to figure out what it does. Thanks
1 Reply
Nik
NikOP•10mo ago
Practically speaking, lets say I have 
model A {
  id          String  @id @default(auto()) @map("_id") @db.ObjectId
  name        String
  b           B?
}
model B {
  id          String  @id @default(auto()) @map("_id") @db.ObjectId
  a           A       @relation(fields: [a_id], references: [id])
  a_id        String  @db.ObjectId @unique
}
model A {
  id          String  @id @default(auto()) @map("_id") @db.ObjectId
  name        String
  b           B?
}
model B {
  id          String  @id @default(auto()) @map("_id") @db.ObjectId
  a           A       @relation(fields: [a_id], references: [id])
  a_id        String  @db.ObjectId @unique
}
I want to be able to call prisma.a.findOrCreate({ data:{name:'hi'}, includes:{ b:true } }) solved 2) 
async findOrCreate<T, A extends Prisma.Args<T, 'create'>>(
          this: T,
          queryArgs: Prisma.Args<T, 'findFirst'>,
          createArgs: A
        ):Promise< Prisma.Result<T, A, 'create'> >{
          const ctx = Prisma.getExtensionContext<T>(this);
          let record = await (ctx as any).findFirst(queryArgs);
          if(!record)
            record = await (ctx as any).create(createArgs);
          return record;
        }
async findOrCreate<T, A extends Prisma.Args<T, 'create'>>(
          this: T,
          queryArgs: Prisma.Args<T, 'findFirst'>,
          createArgs: A
        ):Promise< Prisma.Result<T, A, 'create'> >{
          const ctx = Prisma.getExtensionContext<T>(this);
          let record = await (ctx as any).findFirst(queryArgs);
          if(!record)
            record = await (ctx as any).create(createArgs);
          return record;
        }

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