feat(typegen): Go Type Gen (#687)

* feat(typegen): add route for go

* feat(typegen): cleanup server.ts and set up local typegen for go

* feat(typegen): create go table structs

* feat(typegen): create go view/matview structs

* feat(typegen): create go composite type structs

* feat(typegen): go: handle range types

* feat(typegen): go: test

* feat(typegen): go: format

* feat(typegen): separate go types by operation and add nullable types

* feat(typegen): go: format

* feat(typegen): go: handle empty tables

* chore: update snapshot

---------

Co-authored-by: Bobbie Soedirgo <[email protected]>

README.md

@@ -100,9 +100,14 @@ To start developing, run `npm run dev`. It will set up the database with Docker
 
 If you are fixing a bug, you should create a new test case. To test your changes, add the `-u` flag to `vitest` on the `test:run` script, run `npm run test`, and then review the git diff of the snapshots. Depending on your change, you may see `id` fields being changed - this is expected and you are free to commit it, as long as it passes the CI. Don't forget to remove the `-u` flag when committing.
 
-To make changes to the TypeScript type generation, run `npm run gen:types:typescript` while you have `npm run dev` running.
+To make changes to the type generation, run `npm run gen:types:<lang>` while you have `npm run dev` running,
+where `<lang>` is one of:
+
+- `typescript`
+- `go`
+
 To use your own database connection string instead of the provided test database, run:
-`PG_META_DB_URL=postgresql://postgres:postgres@localhost:5432/postgres npm run gen:types:typescript`
+`PG_META_DB_URL=postgresql://postgres:postgres@localhost:5432/postgres npm run gen:types:<lang>`
 
 ## Licence
 

package.json

@@ -23,6 +23,7 @@
     "build": "tsc -p tsconfig.json && cpy 'src/lib/sql/*.sql' dist/lib/sql",
     "docs:export": "PG_META_EXPORT_DOCS=true node --loader ts-node/esm src/server/server.ts > openapi.json",
     "gen:types:typescript": "PG_META_GENERATE_TYPES=typescript node --loader ts-node/esm src/server/server.ts",
+    "gen:types:go": "PG_META_GENERATE_TYPES=go node --loader ts-node/esm src/server/server.ts",
     "start": "node dist/server/server.js",
     "dev": "trap 'npm run db:clean' INT && run-s db:clean db:run && nodemon --exec node --loader ts-node/esm src/server/server.ts | pino-pretty --colorize",
     "test": "run-s db:clean db:run test:run db:clean",

src/server/routes/generators/go.ts

@@ -0,0 +1,35 @@
+import type { FastifyInstance } from 'fastify'
+import { PostgresMeta } from '../../../lib/index.js'
+import { DEFAULT_POOL_CONFIG } from '../../constants.js'
+import { extractRequestForLogging } from '../../utils.js'
+import { apply as applyGoTemplate } from '../../templates/go.js'
+import { getGeneratorMetadata } from '../../../lib/generators.js'
+
+export default async (fastify: FastifyInstance) => {
+  fastify.get<{
+    Headers: { pg: string }
+    Querystring: {
+      excluded_schemas?: string
+      included_schemas?: string
+    }
+  }>('/', async (request, reply) => {
+    const connectionString = request.headers.pg
+    const excludedSchemas =
+      request.query.excluded_schemas?.split(',').map((schema) => schema.trim()) ?? []
+    const includedSchemas =
+      request.query.included_schemas?.split(',').map((schema) => schema.trim()) ?? []
+
+    const pgMeta: PostgresMeta = new PostgresMeta({ ...DEFAULT_POOL_CONFIG, connectionString })
+    const { data: generatorMeta, error: generatorMetaError } = await getGeneratorMetadata(pgMeta, {
+      includedSchemas,
+      excludedSchemas,
+    })
+    if (generatorMetaError) {
+      request.log.error({ error: generatorMetaError, request: extractRequestForLogging(request) })
+      reply.code(500)
+      return { error: generatorMetaError.message }
+    }
+
+    return applyGoTemplate(generatorMeta)
+  })
+}

src/server/routes/index.ts

@@ -18,7 +18,8 @@ import TablesRoute from './tables.js'
 import TriggersRoute from './triggers.js'
 import TypesRoute from './types.js'
 import ViewsRoute from './views.js'
-import TypeGenRoute from './generators/typescript.js'
+import TypeScriptTypeGenRoute from './generators/typescript.js'
+import GoTypeGenRoute from './generators/go.js'
 import { PG_CONNECTION, CRYPTO_KEY } from '../constants.js'
 
 export default async (fastify: FastifyInstance) => {
@@ -62,5 +63,6 @@ export default async (fastify: FastifyInstance) => {
   fastify.register(TriggersRoute, { prefix: '/triggers' })
   fastify.register(TypesRoute, { prefix: '/types' })
   fastify.register(ViewsRoute, { prefix: '/views' })
-  fastify.register(TypeGenRoute, { prefix: '/generators/typescript' })
+  fastify.register(TypeScriptTypeGenRoute, { prefix: '/generators/typescript' })
+  fastify.register(GoTypeGenRoute, { prefix: '/generators/go' })
 }

src/server/server.ts

@@ -14,6 +14,8 @@ import {
   PG_META_PORT,
 } from './constants.js'
 import { apply as applyTypescriptTemplate } from './templates/typescript.js'
+import { apply as applyGoTemplate } from './templates/go.js'
+import { getGeneratorMetadata } from '../lib/generators.js'
 
 const logger = pino({
   formatters: {
@@ -27,6 +29,37 @@ const logger = pino({
 const app = buildApp({ logger })
 const adminApp = buildAdminApp({ logger })
 
+async function getTypeOutput(): Promise<string | null> {
+  const pgMeta: PostgresMeta = new PostgresMeta({
+    ...DEFAULT_POOL_CONFIG,
+    connectionString: PG_CONNECTION,
+  })
+  const { data: generatorMetadata, error: generatorMetadataError } = await getGeneratorMetadata(
+    pgMeta,
+    {
+      includedSchemas: GENERATE_TYPES_INCLUDED_SCHEMAS,
+    }
+  )
+  if (generatorMetadataError) {
+    throw new Error(generatorMetadataError.message)
+  }
+
+  let output: string | null = null
+  switch (GENERATE_TYPES) {
+    case 'typescript':
+      output = await applyTypescriptTemplate({
+        ...generatorMetadata,
+        detectOneToOneRelationships: GENERATE_TYPES_DETECT_ONE_TO_ONE_RELATIONSHIPS,
+      })
+      break
+    case 'go':
+      output = applyGoTemplate(generatorMetadata)
+      break
+  }
+
+  return output
+}
+
 if (EXPORT_DOCS) {
   // TODO: Move to a separate script.
   await app.ready()
@@ -154,3 +187,8 @@ if (EXPORT_DOCS) {
     adminApp.listen({ port: adminPort, host: PG_META_HOST })
   })
 }
+
+app.listen({ port: PG_META_PORT, host: PG_META_HOST }, () => {
+  const adminPort = PG_META_PORT + 1
+  adminApp.listen({ port: adminPort, host: PG_META_HOST })
+})