prisma.service.ts

prisma.service.tsapps/api/src/common/prisma.service.tsraw ← common2,913 B← Back to the app
1import { Injectable, OnModuleDestroy, OnModuleInit } from "@nestjs/common";
2import { PrismaClient } from "@prisma/client";
3import { loadEnv } from "../config/env.js";
4import { logger } from "./logger.js";
5 
6/**
7 * Prisma client as a Nest provider. The schema lives at the repo root
8 * (../../prisma/schema.prisma); set PRISMA_SCHEMA for unusual checkouts.
9 *
10 * TASK-0135 (pooling + replica): this service is the PRIMARY client — all
11 * writes, transactions, permission decisions, and the `If-Match` version CAS
12 * go through it. It also owns the READER client (`this.reader`): the
13 * read-replica when `DATABASE_REPLICA_URL` is set, otherwise the primary.
14 * The hot-path read sites (block tree load, record listing) call
15 * `this.read()` — the spec's `db.read()`/`db.write()` contract from
16 * `@factory/database-client` (the spec's `prisma/clients.ts`; a package
17 * because the apps compile with `rootDir: "src"`). The replica LAGS — it is
18 * NEVER used for authorization or optimistic-concurrency version checks.
19 */
20@Injectable()
21export class PrismaService extends PrismaClient implements OnModuleInit, OnModuleDestroy {
22  /** The read-replica client (or the primary when no replica is configured). */
23  readonly reader: PrismaClient;
24  /** True when a distinct replica is in use. */
25  readonly hasReplica: boolean;
26 
27  constructor() {
28    const env = loadEnv();
29    super({
30      datasources: { db: { url: env.DATABASE_URL } },
31      log: process.env.NODE_ENV === "production" ? ["warn", "error"] : ["warn", "error"]
32    });
33    const replicaUrl = env.DATABASE_REPLICA_URL?.trim();
34    if (replicaUrl) {
35      this.reader = new PrismaClient({
36        datasources: { db: { url: replicaUrl } },
37        log: ["warn", "error"]
38      });
39      this.hasReplica = true;
40    } else {
41      this.reader = this;
42      this.hasReplica = false;
43    }
44  }
45 
46  /** `db.read()` — replica-routed for tree/listing/search reads ONLY. */
47  read(): PrismaClient {
48    return this.reader;
49  }
50 
51  /** `db.write()` — the primary (this service). Writes + version CAS. */
52  write(): PrismaClient {
53    return this;
54  }
55 
56  async onModuleInit(): Promise<void> {
57    try {
58      await this.$connect();
59      if (this.hasReplica) {
60        // Surface a broken replica URL at boot (a bad replica must not fail
61        // lazily on the first tree load). The primary already connected.
62        await this.reader.$connect();
63        logger.info("prisma connected (primary + read-replica)");
64      } else {
65        logger.info("prisma connected");
66      }
67    } catch (err) {
68      // Boot without a live DB only in non-prod; surface the failure in prod.
69      logger.warn(`prisma connect failed: ${(err as Error).message}`);
70      if (process.env.NODE_ENV === "production") throw err;
71    }
72  }
73 
74  async onModuleDestroy(): Promise<void> {
75    await this.$disconnect();
76    if (this.hasReplica) await this.reader.$disconnect();
77  }
78}
79