feat: add posgresql connector

.env.example

@@ -0,0 +1 @@
+POSTGRESQL_URL=postgresql://<user>:@localhost:5432/sql0

.gitignore

@@ -10,3 +10,4 @@ tmp
 __*
 .data
 .tmp
+.env

package.json

@@ -36,12 +36,15 @@
   },
   "devDependencies": {
     "@types/better-sqlite3": "^7.6.4",
+    "@types/pg": "^8.6.6",
     "@vitest/coverage-c8": "^0.31.1",
     "better-sqlite3": "^8.3.0",
     "changelogen": "^0.5.3",
+    "dotenv": "^16.0.3",
     "eslint": "^8.40.0",
     "eslint-config-unjs": "^0.1.0",
     "jiti": "^1.18.2",
+    "pg": "^8.11.0",
     "prettier": "^2.8.8",
     "typescript": "^5.0.4",
     "unbuild": "^1.2.1",

src/connectors/postgresql.ts

@@ -0,0 +1,65 @@
+import { Client, ClientConfig, Query } from "pg";
+
+import type { Connector, Statement } from "../types";
+
+export type ConnectorOptions = { url: string } | ClientConfig;
+
+export default function sqliteConnector(opts: ConnectorOptions) {
+  let _client: undefined | Client | Promise<Client>;
+  function getClient() {
+    if (_client) {
+      return _client;
+    }
+    const client = new Client("url" in opts ? opts.url : opts);
+    _client = client.connect().then(() => {
+      _client = client;
+      return _client;
+    });
+    return _client;
+  }
+
+  async function query(sql: string, params?: unknown[]) {
+    const client = await getClient();
+    return client.query(normalizeParams(sql), params);
+  }
+
+  return <Connector>{
+    name: "postgresql",
+    exec(sql: string) {
+      return query(sql);
+    },
+    prepare(sql: string) {
+      const stmt = <Statement>{
+        _sql: sql,
+        _params: [],
+        bind(...params) {
+          if (params.length > 0) {
+            this._params = params;
+          }
+          return stmt;
+        },
+        all(...params) {
+          return query(this._sql, params || this._params).then((r) => r.rows);
+        },
+        run(...params) {
+          return query(this._sql, params || this._params).then((r) => ({
+            result: r,
+          }));
+        },
+        get(...params) {
+          // TODO: Append limit?
+          return query(this._sql, params || this._params).then(
+            (r) => r.rows[0]
+          );
+        },
+      };
+      return stmt;
+    },
+  };
+}
+
+// https://www.postgresql.org/docs/9.3/sql-prepare.html
+function normalizeParams(sql: string) {
+  let i = 0;
+  return sql.replace(/\?/g, () => `$${++i}`);
+}

src/index.ts

@@ -3,6 +3,7 @@ export * from "./types";
 
 export const connectors = {
   sqlite: "sql0/connectors/better-sqlite3",
+  postgresql: "sql0/connectors/postgresql",
 } as const;
 
 export type ConnectorName = keyof typeof connectors;

test/connectors/_tests.ts

@@ -7,9 +7,10 @@ export function testConnector(opts: { connector: Connector }) {
     db = createDatabase(opts.connector);
   });
 
-  it("create table", async () => {
+  it("drop and create table", async () => {
+    await db.exec(`DROP TABLE IF EXISTS users`);
     const res = await db.exec(
-      "CREATE TABLE IF NOT EXISTS users (id TEXT PRIMARY KEY, firstName TEXT, lastName TEXT, email TEXT)"
+      `CREATE TABLE users ("id" TEXT PRIMARY KEY, "firstName" TEXT, "lastName" TEXT, "email" TEXT)`
     );
     expect(res).toBeDefined();
   });

test/connectors/postgresql.test.ts

@@ -0,0 +1,14 @@
+import { describe } from "vitest";
+import connector from "../../src/connectors/postgresql";
+import { testConnector } from "./_tests";
+
+describe.runIf(process.env.POSTGRESQL_URL)(
+  "connectors: postgresql.test",
+  () => {
+    testConnector({
+      connector: connector({
+        url: process.env.POSTGRESQL_URL!,
+      }),
+    });
+  }
+);

vitest.config.ts

@@ -0,0 +1,7 @@
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  test: {
+    setupFiles: ["dotenv/config"],
+  },
+});