Phase 7

src/lib/db/mysql-pool-config.ts

@@ -0,0 +1,31 @@
+/**
+ * Builds the `mariadb` pool config from `DATABASE_URL`, shared by every
+ * Prisma Client instance in the app (the main app client, the seed
+ * script, and the integration-test fixtures) so the UTC-timezone and
+ * connection-limit handling can't drift between them. See
+ * src/lib/db/prisma.ts for why `timezone`/`sessionVariables` matter — this
+ * file exists only because that reasoning needs to apply to all three
+ * call sites, not because the logic itself is complex.
+ */
+export function buildMysqlPoolConfig(databaseUrl: string | undefined) {
+  if (!databaseUrl) throw new Error("DATABASE_URL is not set.");
+
+  // Accept both `mysql://` and `mariadb://` — the `mariadb` driver's own
+  // string parser only recognizes the latter, but the `URL` global parses
+  // either scheme fine since we build the pool config object ourselves.
+  const url = new URL(databaseUrl);
+
+  return {
+    host: url.hostname,
+    port: url.port ? Number(url.port) : 3306,
+    user: decodeURIComponent(url.username),
+    password: decodeURIComponent(url.password),
+    database: url.pathname.replace(/^\//, ""),
+    connectionLimit: Number(process.env.DATABASE_CONNECTION_LIMIT ?? 5),
+    connectTimeout: Number(process.env.DATABASE_CONNECT_TIMEOUT_MS ?? 10_000),
+    // Load-bearing, not cosmetic — see src/lib/db/prisma.ts's file header.
+    timezone: "Etc/UTC",
+    sessionVariables: { time_zone: "+00:00" },
+    ssl: process.env.DATABASE_SSL === "true" ? { rejectUnauthorized: true } : undefined,
+  };
+}

src/lib/db/prisma.ts

@@ -1,24 +1,34 @@
 import { PrismaClient } from "@/generated/prisma/client";
-import { PrismaPg } from "@prisma/adapter-pg";
+import { PrismaMariaDb } from "@prisma/adapter-mariadb";
+import { buildMysqlPoolConfig } from "./mysql-pool-config";
 
 /**
  * Single Prisma Client instance for the whole app.
  *
  * Prisma 7 requires a driver adapter instead of a `datasource.url` in the
- * schema (see prisma/schema.prisma). This is the ONLY file that imports
- * `@prisma/adapter-pg` — switching to MySQL later means swapping this one
- * adapter (`@prisma/adapter-mariadb`), updating `datasource.provider` in
- * the schema, and re-running `prisma migrate dev`. No other file in the
- * app touches the database driver directly.
+ * schema (see prisma/schema.prisma). This is the ONLY file that imports a
+ * database driver directly — every other file goes through `prisma`.
+ *
+ * Migrated from PostgreSQL (`@prisma/adapter-pg`) to MySQL in Phase 7 — see
+ * docs/phase-7-summary.md for the full record. `@prisma/adapter-mariadb` is
+ * Prisma's one official driver adapter for BOTH MySQL and MariaDB (there is
+ * no separate "adapter-mysql" package): the underlying `mariadb` npm driver
+ * speaks the MySQL wire protocol and is Prisma's documented, supported way
+ * to connect to a genuine MySQL server. The package name is not a sign
+ * we're accidentally targeting MariaDB — `datasource.provider` in
+ * schema.prisma is `"mysql"`, and every environment this app runs against
+ * (local Docker, CI, and the documented production target) is real MySQL.
+ *
+ * See mysql-pool-config.ts for why the pool is built from a parsed object
+ * rather than passed the raw connection string — the short version is that
+ * the UTC-timezone handling it sets is load-bearing, not cosmetic.
  */
 
 const globalForPrisma = globalThis as unknown as {
   prisma: PrismaClient | undefined;
 };
 
-const adapter = new PrismaPg({
-  connectionString: process.env.DATABASE_URL,
-});
+const adapter = new PrismaMariaDb(buildMysqlPoolConfig(process.env.DATABASE_URL));
 
 export const prisma =
   globalForPrisma.prisma ??