Generating Specs

Before running drift-guard you need schema files on disk. Below are the most common tools for each language and schema type.

OpenAPI

Node.js

Tool	Framework	Command	Output
@nestjs/swagger	NestJS	nest build + export via SwaggerModule	openapi.json
swagger-jsdoc	Express / Fastify	npx swagger-jsdoc -d swaggerDef.js routes/*.js -o openapi.json	openapi.json
fastify-swagger	Fastify	app.ready(() => writeFileSync('openapi.json', JSON.stringify(app.swagger())))	openapi.json
tsoa	Express / Koa	npx tsoa spec	build/swagger.json

Go

Tool	Framework	Command	Output
swag	Gin / Echo / Fiber	swag init -g main.go -o docs	docs/swagger.yaml
oapi-codegen	net/http / Chi	schema-first — write .yaml, generate code	hand-authored
huma	net/http / Chi	schema auto-generated at startup; dump via /openapi.json	served at runtime

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GraphQL

Node.js

Tool	Framework	Command	Output
graphql-inspector	Apollo / Yoga	npx graphql-inspector introspect http://localhost:4000 --write schema.graphql	schema.graphql
get-graphql-schema	Any	npx get-graphql-schema http://localhost:4000 > schema.graphql	schema.graphql
@graphql-codegen	Apollo / Yoga	npx graphql-codegen --config codegen.ts	configurable
Apollo Server	Apollo	rover graph introspect http://localhost:4000 > schema.graphql	schema.graphql

Go

Tool	Framework	Command	Output
gqlgen	gqlgen	schema-first — graph/schema.graphqls is your source	hand-authored
graph-gophers/graphql-go	net/http	schema defined as Go string literal; export to file	hand-authored
Introspection	Any server	curl -X POST http://localhost:8080/graphql -d '{"query":"{__schema{...}}"}' | jq > schema.json	schema.json

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gRPC / Protobuf

Node.js

Tool	Framework	Command	Output
@grpc/proto-loader	grpc-js	.proto files are the source of truth — check them in directly	hand-authored
ts-proto	grpc-js	protoc --plugin=protoc-gen-ts_proto --ts_proto_out=. service.proto	generated TS; .proto is source
buf	Any	buf build --output image.bin (or use .proto files directly)	.proto / BSR

Go

Tool	Framework	Command	Output
protoc	google.golang.org/grpc	.proto files are the source of truth — check them in directly	hand-authored
buf	Any	buf generate	generated Go; .proto is source
grpc-gateway	grpc-gateway	annotate .proto, generate OpenAPI via protoc-gen-openapiv2	apidocs.swagger.json

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Quick reference

Schema type	Minimum drift-guard input
OpenAPI	Any .yaml or .json file valid against OpenAPI 3.x
GraphQL	SDL file (.graphql / .gql) or introspection JSON
gRPC	A .proto file using syntax = "proto3"