@metaengine/graphql-angular

Generate Angular TypeScript services and models from GraphQL schemas.

Typed queries, mutations & subscriptions, native Angular dependency injection, and HttpClient-based data fetching.

Install

npm install --save-dev @metaengine/graphql-angular

Or use directly with npx:

npx @metaengine/graphql-angular <input> <output>

Requirements

• Node.js 18.0 or later
• .NET 8.0 or later runtime (Download)

Quick start

npx @metaengine/graphql-angular schema.graphql ./src/api \
  --inject-function \
  --provided-in root \
  --documentation

CLI options

| Option | Description | Default | |--------|-------------|---------| | --fragments | Emit reusable named fragments for object-type selections | false | | --one-of-inputs | Generate idiomatic @oneOf input types (tagged-union inputs) | false | | --custom-scalar <Scalar=target> | Map a GraphQL custom scalar to a TS type. Repeatable. See Custom scalar mappings | - | | --provided-in <scope> | Angular injection scope (root, any, platform) | - | | --base-url-token <name> | Injection token name for base URL | BASE_URL | | --inject-function | Use inject() instead of constructor injection | false | | --interceptors | Generate Angular interceptors for cross-cutting concerns | false | | --error-handling | Smart error handling based on HTTP status semantics | false | | --retries <max-attempts> | Enable retries with exponential backoff (status codes 429, 503) | - | | --documentation | Generate JSDoc comments from SDL descriptions | false | | --date-transformation | Convert Date-typed scalar fields (e.g. DateTime) in responses to Date objects | false | | --options-threshold <n> | Parameter count for options object | 4 | | --types-barrel | Emit an index.ts barrel per folder plus a root index.ts re-exporting everything | false | | --clean | Clean output directory (remove files not in generation) | false | | --verbose | Enable verbose logging | false | | --help, -h | Show help message | - |

Custom scalar mappings

GraphQL custom scalars resolve to idiomatic TypeScript types. Well-known scalars are mapped out of the box; any other custom scalar defaults to string.

| GraphQL scalar | TypeScript type | |----------------|-----------------| | DateTime, Date, Time, DateTimeOffset | Date | | Decimal, Long, BigInt, ULong, UInt, Short, Byte | number | | UUID, Guid, Email, URL, URI | string |

Use --custom-scalar to override the TS type emitted for a scalar. Repeatable. Unsupported targets are hard errors.

| Target | Emitted TS type | |--------|-----------------| | string | string | | number | number | | boolean | boolean | | Date | Date |

npx @metaengine/graphql-angular schema.graphql ./src/api \
  --custom-scalar DateTime=string \
  --custom-scalar UUID=string

Integer-like scalars (Long, BigInt, ULong) map to number by design so request variables survive JSON.stringify.

See it live

Try the generator with your own schema at https://www.metaengine.eu/converters.

License

MIT

Support

For issues and feature requests, please visit: https://github.com/meta-engine/graphql-angular/issues