Make db:generate run through PGlite by default

README.md

@@ -44,7 +44,7 @@ npm install pgstrap --save-dev
    npm run db:migrate
    ```
 
-6. Generate types and structure:
+6. Generate types and structure without running a local Postgres server:
    ```bash
    npm run db:generate
    ```
@@ -55,7 +55,8 @@ npm install pgstrap --save-dev
 
 - `npm run db:migrate` - Run pending migrations
 - `npm run db:reset` - Drop and recreate the database, then run all migrations
-- `npm run db:generate` - Generate types and structure dumps. Use `pgstrap generate --pglite` to run migrations against an in-memory PGlite instance.
+- `npm run db:generate` - Generate types and structure dumps against an in-memory PGlite instance by default.
+- `pgstrap generate --no-pglite` - Generate from `DATABASE_URL` or the configured Postgres defaults instead of PGlite.
 - `npm run db:create-migration` - Create a new migration file
 
 ### Configuration

src/cli.ts

@@ -35,10 +35,18 @@ import { getProjectContext } from "./get-project-context"
     "generate",
     "generate types and sql documentation from database",
     (yargs) => {
-      yargs.option("pglite", { type: "boolean", default: false })
+      yargs.option("pglite", {
+        describe:
+          "run migrations in an in-memory PGlite database before generating output",
+        type: "boolean",
+        default: true,
+      })
     },
-    async (argv) => {
-      generate({ ...(await getProjectContext()), pglite: !!argv.pglite })
+    async (argv): Promise<void> => {
+      await generate({
+        ...(await getProjectContext()),
+        pglite: argv.pglite !== false,
+      })
     },
   )
   .parse()

src/generate.ts

@@ -1,9 +1,7 @@
 import * as zg from "zapatos/generate"
-import {
-  getConnectionStringFromEnv,
-  getPgConnectionFromEnv,
-} from "pg-connection-from-env"
-import { Context } from "./get-project-context"
+import { getConnectionStringFromEnv } from "pg-connection-from-env"
+import type { AddressInfo } from "node:net"
+import type { Context } from "./get-project-context"
 import { dumpTree } from "pg-schema-dump"
 import path from "path"
 import { migrate } from "./migrate"
@@ -12,12 +10,12 @@ export const generate = async ({
   schemas,
   defaultDatabase,
   dbDir,
-  pglite = false,
+  pglite = true,
   migrationsDir,
 }: Pick<Context, "schemas" | "defaultDatabase" | "dbDir"> & {
   pglite?: boolean
   migrationsDir?: string
-}) => {
+}): Promise<void> => {
   dbDir = dbDir ?? "./src/db"
   migrationsDir = migrationsDir ?? path.join(dbDir, "migrations")
 
@@ -27,65 +25,93 @@ export const generate = async ({
     const net = await import("node:net")
 
     const db = new PGlite()
+    const prevDbUrl = process.env.DATABASE_URL
+    let server: ReturnType<typeof net.createServer> | undefined
 
-    await migrate({
-      client: db as any,
-      migrationsDir,
-      defaultDatabase,
-      cwd: process.cwd(),
-      schemas,
-    })
+    try {
+      await migrate({
+        client: db as any,
+        migrationsDir,
+        defaultDatabase,
+        cwd: process.cwd(),
+        schemas,
+      })
 
-    const server = net.createServer(async (socket) => {
-      const connection = await fromNodeSocket(socket, {
-        serverVersion: "16.3 (PGlite)",
-        auth: {
-          method: "password",
-          validateCredentials: ({ username, password }: any) =>
-            username === "postgres" && password === "postgres",
-          getClearTextPassword: () => "postgres",
-        },
-        async onStartup() {
-          await (db as any).waitReady
-        },
-        async onMessage(data: Uint8Array, { isAuthenticated }: any) {
-          if (!isAuthenticated) return
-          try {
-            const { data: responseData } = await (db as any).execProtocol(data)
-            return responseData
-          } catch {
-            return undefined
-          }
-        },
+      const pgliteServer = net.createServer(async (socket) => {
+        await fromNodeSocket(socket, {
+          serverVersion: "16.3 (PGlite)",
+          auth: {
+            method: "password",
+            validateCredentials: ({
+              username,
+              password,
+            }: {
+              username: string
+              password: string
+            }) => username === "postgres" && password === "postgres",
+            getClearTextPassword: () => "postgres",
+          },
+          async onStartup(): Promise<void> {
+            await (db as any).waitReady
+          },
+          async onMessage(
+            data: Uint8Array,
+            { isAuthenticated }: { isAuthenticated: boolean },
+          ): Promise<Uint8Array | undefined> {
+            if (!isAuthenticated) return undefined
+            try {
+              const { data: responseData } = await (db as any).execProtocol(
+                data,
+              )
+              return responseData
+            } catch {
+              return undefined
+            }
+          },
+        })
       })
-    })
+      server = pgliteServer
 
-    await new Promise<void>((resolve) => server.listen(0, resolve))
-    const port = (server.address() as any).port
-    const connectionString = `postgres://postgres:postgres@127.0.0.1:${port}/postgres`
+      await new Promise<void>((resolve) => pgliteServer.listen(0, resolve))
+      const address = pgliteServer.address() as AddressInfo
+      const connectionString = `postgres://postgres:postgres@127.0.0.1:${address.port}/postgres`
 
-    const prevDbUrl = process.env.DATABASE_URL
-    process.env.DATABASE_URL = connectionString
+      process.env.DATABASE_URL = connectionString
+
+      await zg.generate({
+        db: {
+          connectionString,
+        },
+        schemas: Object.fromEntries(
+          schemas.map((s) => [s, { include: "*", exclude: [] }]),
+        ),
+        outDir: dbDir,
+      })
+
+      await dumpTree({
+        targetDir: path.join(dbDir, "structure"),
+        defaultDatabase: "postgres",
+        schemas,
+      })
+    } finally {
+      const openServer = server
 
-    await zg.generate({
-      db: {
-        connectionString,
-      },
-      schemas: Object.fromEntries(
-        schemas.map((s) => [s, { include: "*", exclude: [] }]),
-      ),
-      outDir: dbDir,
-    })
+      if (openServer) {
+        await new Promise<void>((resolve, reject) => {
+          openServer.close((error?: Error) => {
+            if (error) {
+              reject(error)
+              return
+            }
 
-    await dumpTree({
-      targetDir: path.join(dbDir, "structure"),
-      defaultDatabase: "postgres",
-      schemas,
-    })
+            resolve()
+          })
+        })
+      }
 
-    server.close()
-    if (prevDbUrl === undefined) delete process.env.DATABASE_URL
-    else process.env.DATABASE_URL = prevDbUrl
+      if (prevDbUrl === undefined) delete process.env.DATABASE_URL
+      else process.env.DATABASE_URL = prevDbUrl
+    }
     return
   }
 

src/init.ts

@@ -16,7 +16,7 @@ export const initPgstrap = async (ctx: Pick<Context, "cwd">) => {
 
   pkg.scripts["db:migrate"] = "pgstrap migrate"
   pkg.scripts["db:reset"] = "pgstrap reset"
-  pkg.scripts["db:generate"] = "pgstrap generate"
+  pkg.scripts["db:generate"] = "pgstrap generate --pglite"
   pkg.scripts["db:create-migration"] = "pgstrap create-migration"
 
   if (!pkg.devDependencies) pkg.devDependencies = {}

tests/generate.pglite.test.ts

@@ -13,23 +13,29 @@ exports.down = async (pgm) => {
 }
 `
 
-test("generate with pglite runs migrations and dumps structure", async () => {
+const makeProject = (): {
+  tmp: string
+  migrationsDir: string
+  dbDir: string
+} => {
   const tmp = fs.mkdtempSync(path.join(os.tmpdir(), "pgstrap-generate-"))
   const migrationsDir = path.join(tmp, "migrations")
+  const dbDir = path.join(tmp, "db")
+
   fs.mkdirSync(migrationsDir, { recursive: true })
   fs.writeFileSync(
     path.join(migrationsDir, "001_create_table.js"),
     migrationFile,
   )
 
-  await generate({
-    schemas: ["public"],
-    defaultDatabase: "postgres",
-    dbDir: path.join(tmp, "db"),
+  return {
+    tmp,
     migrationsDir,
-    pglite: true,
-  })
+    dbDir,
+  }
+}
 
+const expectGeneratedSchema = (tmp: string): void => {
   const zapatosFile = path.join(tmp, "db", "zapatos", "schema.d.ts")
   const structureDir = path.join(
     tmp,
@@ -42,6 +48,39 @@ test("generate with pglite runs migrations and dumps structure", async () => {
 
   expect(fs.existsSync(zapatosFile)).toBe(true)
   expect(fs.existsSync(path.join(structureDir, "table.sql"))).toBe(true)
+}
+
+test("generate defaults to pglite and dumps structure without a running postgres server", async () => {
+  const { tmp, migrationsDir, dbDir } = makeProject()
+
+  try {
+    await generate({
+      schemas: ["public"],
+      defaultDatabase: "postgres",
+      dbDir,
+      migrationsDir,
+    })
+
+    expectGeneratedSchema(tmp)
+  } finally {
+    fs.rmSync(tmp, { recursive: true, force: true })
+  }
+})
+
+test("generate with pglite runs migrations and dumps structure", async () => {
+  const { tmp, migrationsDir, dbDir } = makeProject()
+
+  try {
+    await generate({
+      schemas: ["public"],
+      defaultDatabase: "postgres",
+      dbDir,
+      migrationsDir,
+      pglite: true,
+    })
 
-  fs.rmSync(tmp, { recursive: true, force: true })
+    expectGeneratedSchema(tmp)
+  } finally {
+    fs.rmSync(tmp, { recursive: true, force: true })
+  }
 })

tests/init.test.ts

@@ -25,6 +25,6 @@ test("initPgstrap writes scripts to package.json", async () => {
   )
   expect(pkg.scripts["db:migrate"]).toBe("pgstrap migrate")
   expect(pkg.scripts["db:reset"]).toBe("pgstrap reset")
-  expect(pkg.scripts["db:generate"]).toBe("pgstrap generate")
+  expect(pkg.scripts["db:generate"]).toBe("pgstrap generate --pglite")
   expect(pkg.scripts["db:create-migration"]).toBe("pgstrap create-migration")
 })