wgc grpc-service generate

The generate command generates a protobuf definition and mapping file for a gRPC service from a GraphQL schema, which can be used to implement a gRPC service and can be used for the composition. It supports two modes:

Schema Mode: Generates a protobuf definition that mirrors the GraphQL schema. Used for implementing Subgraphs in gRPC (Connect Backend).
Operations Mode: Generates a protobuf definition based on a set of GraphQL operations. Used for generating client SDKs (Connect Client).

Usage

wgc grpc-service generate [options] [service-name]

Arguments

Argument	Description	Default
`service-name`	Name of the gRPC service	`service.v1`

Options

Option	Description	Default
`-i, --input <path-to-input>`	The GraphQL schema file to generate a protobuf schema from	Required
`-o, --output <path-to-output>`	The output directory for the protobuf schema	`.`
`-p, --package-name <name>`	The name of the proto package	`service.v1`
`-g, --go-package <name>`	Adds an `option go_package` to the proto file	None
`-w, --with-operations <path>`	Path to directory containing GraphQL operation files. Enables Operations Mode.	None
`-l, --proto-lock <path>`	Path to existing proto lock file.	`<outdir>/service.proto.lock.json`
`--custom-scalar-mapping <json>`	Custom scalar type mappings as JSON string. Example: `{"DateTime":"google.protobuf.Timestamp"}`	None
`--custom-scalar-mapping-file <path>`	Path to JSON file containing custom scalar type mappings.	None
`--max-depth <number>`	Maximum recursion depth for processing nested selections.	`50`

Description

This command generates a protobuf definition for a gRPC service from a GraphQL schema.

Examples

Generate a protobuf definition for a gRPC service from a GraphQL schema (Schema Mode)

wgc grpc-service generate -i ./schema.graphql -o ./service MyService

Generate a protobuf definition from operations (Operations Mode)

wgc grpc-service generate \
  -i ./schema.graphql \
  -o ./gen \
  --with-operations ./operations \
  --package-name my.service.v1 \
  MyService

Define a custom package name

wgc grpc-service generate -i ./schema.graphql -o ./service MyService --package-name my.custom.package

Define a custom go package name

wgc grpc-service generate -i ./schema.graphql -o ./service MyService --go-package github.com/wundergraph/cosmo/service/my-service

Output

The command generates multiple files in the output directory:

service.proto: The protobuf definition for the gRPC service
service.mapping.json: The mapping file for the gRPC service (Schema Mode only)
service.proto.lock.json: The lock file for the protobuf definition

The generated protobuf definition can be used to implement a gRPC service in any language that supports protobuf, or to generate client SDKs. The mapping and the protobuf definition is needed for the composition part. See also: gRPC Services · GraphQL Support for gRPC Integration

​wgc grpc-service generate

​Usage

​Arguments

​Options

​Description

​Examples

​Generate a protobuf definition for a gRPC service from a GraphQL schema (Schema Mode)

​Generate a protobuf definition from operations (Operations Mode)

​Define a custom package name

​Define a custom go package name

​Output