Prisma-schema-transformer NPM

prisma-schema-transformer

EXPERIMENTAL

This project utilizes the getDMMF method from @prisma/sdk to perform some post-processing work on generated Prisma schema, including the following.

Transform snake_case to camelCase,
Properly singularize or pluralize model and field name.
Add @updatedAt attribute to field in the event of column name is updated_at
Ignore models from the schema.

TODO

Auto generate the generator and datasource nodes.

Install

$ yarn global add prisma-schema-transformer

Usage

$ prisma-schema-transformer prisma/schema.prisma

Usage
  $ prisma-schema-transformer [options] [...args]

Specify a schema:
  $ prisma-schema-transformer ./schema.prisma

Instead of saving the result to the filesystem, you can also print it
  $ prisma-schema-transformer ./schema.prisma --print

Exclude some models from the output
  $ prisma-schema-transformer ./schema.prisma --deny knex_migrations --deny knex_migration_lock

Options:
  --print   Do not save
  --deny    Exlucde model from output
  --help    Help
  --version Version info

Motivation

Using snake_case in database and automatically transform generated Prisma schema to camelCase with @map and @@map as needed to map the new name back to the database.

There is a snippet provided by @TLadd, but I found regex a bit unreliable.

How does it work

getDMMF parses the Prisma schema file into dmmf(datamodel meta format), which we can use to do some post-processing on the Prisma internal data structure.

Deserializer

There does not seem to be a printer or a deserializer for DMMF, source. You can learn more about the implementation at deserializer.ts. It is responsible for converting a serialized Prisma schema, DMMF, back to plain text file.

It's hacky, but it works. Some test fixtures are taken from the @prisma/sdk repository for testing. We use the getDMMF method to compare the serialized structure of original and transformed Prisma schema, make sure they are identical.