refactor(lds)/docs(lds): forward options from subscribeToLogicalDecoding to PgLogicalDecoding and add doc comments to describe them

Author: ab-pm

packages/lds/src/index.ts

@@ -2,14 +2,13 @@
 import PgLogicalDecoding, {
   changeToRecord,
   changeToPk,
+  LdsOptions,
 } from "./pg-logical-decoding";
 import FatalError from "./fatal-error";
 
-export interface Options {
-  slotName?: string;
-  tablePattern?: string;
+export interface Options extends LdsOptions {
+  /** Number of milliseconds between polls. Defaults to `200`. */
   sleepDuration?: number;
-  temporary?: boolean;
 }
 
 const DROP_STALE_SLOTS_INTERVAL = 15 * 60 * 1000;
@@ -57,18 +56,9 @@ export default async function subscribeToLogicalDecoding(
   callback: AnnounceCallback,
   options: Options = {}
 ): Promise<LDSubscription> {
-  const {
-    slotName = "postgraphile",
-    tablePattern = "*.*",
-    sleepDuration = 200,
-    temporary = false,
-  } = options;
+  const { sleepDuration = 200 } = options;
   let lastLsn: string | null = null;
-  const client = new PgLogicalDecoding(connectionString, {
-    tablePattern,
-    slotName,
-    temporary,
-  });
+  const client = new PgLogicalDecoding(connectionString, options);
 
   // We must do this before we create the temporary slot, since errors will release a temporary slot immediately
   await client.dropStaleSlots();
@@ -81,7 +71,7 @@ export default async function subscribeToLogicalDecoding(
     } else if (e.code === "42710") {
       // Slot already exists; ignore.
     } else if (e.code === "42602") {
-      throw new FatalError(`Invalid slot name '${slotName}'?`, e);
+      throw new FatalError(`Invalid slot name '${client.slotName}'?`, e);
     } else {
       console.error(
         "An unhandled error occurred when attempting to create the replication slot:"
@@ -151,7 +141,7 @@ export default async function subscribeToLogicalDecoding(
           }
         }
       }
-      if (!temporary && nextStaleCheck < Date.now()) {
+      if (!client.temporary && nextStaleCheck < Date.now()) {
         // Roughly every 15 minutes, drop stale slots.
         nextStaleCheck = Date.now() + DROP_STALE_SLOTS_INTERVAL;
         client.dropStaleSlots().catch(e => {

packages/lds/src/pg-logical-decoding.ts

@@ -94,9 +94,12 @@ const toLsnData = ([lsn, data]: [string, string]): Payload => ({
   data: JSON.parse(data),
 });
 
-interface Options {
+export interface LdsOptions {
+  /** The 'add-tables' wal2json parameter. Defaults to `*.*`. */
   tablePattern?: string;
+  /** The [replication slot](https://www.postgresql.org/docs/current/logicaldecoding-explanation.html#LOGICALDECODING-REPLICATION-SLOTS) identifier. Defaults to `postgraphile`. */
   slotName?: string;
+  /** Whether `.createSlot()` should create a temporary replication slot which will be limited to the `client` session and gets cleaned up automatically. Defaults to `false`. */
   temporary?: boolean;
 }
 
@@ -108,7 +111,7 @@ export default class PgLogicalDecoding extends EventEmitter {
   private pool: pg.Pool | null;
   private client: Promise<pg.PoolClient> | null;
 
-  constructor(connectionString: string, options?: Options) {
+  constructor(connectionString: string, options?: LdsOptions) {
     super();
     this.connectionString = connectionString;
     const {