DataLake GraphQL Wrapper
Made with ❤️ by DB Systel GmbH

The DataLake GraphQL Wrapper provides a GraphQL API for presto/trino.

Features

• Automatic endpoint generation via interactive cli
  • Generates the interfaces and available endpoint fields based on the fetched database schema
  • Generates the filter fields for all root fields
  • Sorting
  • Pagination
• Support for nested fields
• date/time transformation
• Written in TypeScript
• Easy to extend
• Using only Open Source Software
• It's free

Installation

git clone git@github.com:dbsystel/datalake-graphql-wrapper.git
cd datalake-graphql-wrapper
npm i
cp .env.example .env

Run the dev server

# Generate the index file to have all schemas available
npm run cli:index

# Start the dev server
npm run dev

Configuration

To get started, you have to update the .env file.

Variable	Required	Description
ENGINE_TYPE	Yes	Changes the header variable to switch between presto and trino. The value will be used in the sql client. Valid values are: trino / presto
ENGINE_HOST	Yes	Presto/Trino coordinator hostname or address
ENGINE_PORT	Yes	Presto/Trino coordinator port
ENGINE_CATALOG	Yes	Presto/Trino catalog name
ENGINE_USERNAME	Yes	User which will be used to login
ENGINE_PASSWORD	Yes	Password for the user
ENGINE_SOURCE	No	Source name which will be used for the query. Default is nodejs-client

Command Line Interface

Available commands

# Start the interactive endpoint generation
npm run cli

# Generate only the index.ts with all generated schemata
npm run cli:index

The following args are available for npm run cli

Arg	Description	Example
--schema	Sets the schema name and skips the cli prompt	npm run cli -- --schema<schemaname>
--table	Sets the table and skips the cli prompt. You can define multiple tables. Should be only used if you use --schema	npm run cli -- --schema<schemaname> --table <table1_in_schema> --table <table2_in_schema>
--lint	Disable lint. Helpful if you want to run the code generator multiple times. ( e.g. for different schemas )	npm run cli -- --lint false
--index	Disable index file generation. Helpful if you want to run the code generator multiple times. ( e.g. for different schemas )	npm run cli -- --index false
--indexonly	Skips the questions for schema/table and generates only the src/schema/index.ts file based on the existing endpoints. ( helpful if you created your own endpoint)	npm run cli -- --onlyindex true / Alias: npm run cli:index

Generate Endpoints

To start the code generator you have to run the following command.

npm run cli

Or if you know the schema and tablename, you can also use this command:

npm run cli -- --schema <schemaname> --table <tablename>

Generate only the src/schema/index.ts

npm run cli:index

Start the server

To run the server in development mode:

npm run dev

Otherwise, use:

npm run start

Compliance

We're using REUSE to ensure everything is compliant.

To install it locally, please ensure that you have python installed.

Run the following command to install it:

pip install -r requirements.txt

To run the linter:

reuse lint

Todos

• Add tests
• More documentation
• Add/Create some HowTos
  • Manual endpoint creation
  • Authorization

Credits

• https://pothos-graphql.dev
• https://the-guild.dev/graphql/yoga-server
• https://github.com/tagomoris/presto-client-node

License

This project is licensed under Apache-2.0

Contribute

See how to contribute

---

Trino is open source software licensed under the Apache License 2.0 and supported by the Trino Software Foundation.

Presto is a registered trademark of LF Projects, LLC.