refactor: replace ignored numeric literals with constants

src/integrations/tbank/decimal.ts

@@ -1,12 +1,14 @@
 import { Decimal } from '../../common/decimal';
 
+const MISSING_PROTO_COMPONENT = 0;
+
 const NANO = 1_000_000_000n;
 
 export type ProtoDecimal = { nano?: number | string; units?: number | string };
 
 export function decimal(value: ProtoDecimal): Decimal {
   return {
-    value: BigInt(value.units ?? 0) * NANO + BigInt(value.nano ?? 0),
+    value: BigInt(value.units ?? MISSING_PROTO_COMPONENT) * NANO + BigInt(value.nano ?? MISSING_PROTO_COMPONENT),
     scale: 9,
   };
 }

src/integrations/tbank/instrument-metadata.repository.ts

@@ -13,6 +13,11 @@ import type { TbankInstrument } from './tbank.client';
 import { PrismaService } from '../../prisma/prisma.service';
 import { tbankSourceTtlMs } from './tbank-source.policy';
 
+const FIRST_BATCH_OFFSET = 0;
+const UNCHANGED_REVISION_INCREMENT = 0;
+const REVISION_INCREMENT = 1;
+const MISSING_DATA_REVISION = 0;
+
 export type MetadataIdentity = {
   figi?: null | string;
   instrumentUid?: null | string;
@@ -59,7 +64,7 @@ export class InstrumentMetadataRepository {
           ),
         ];
         for (
-          let offset = 0;
+          let offset = FIRST_BATCH_OFFSET;
           offset < values.length;
           offset += metadataReadBatchSize
         ) {
@@ -81,7 +86,7 @@ export class InstrumentMetadataRepository {
       ];
       const instruments: MetadataRow[] = [];
       for (
-        let offset = 0;
+        let offset = FIRST_BATCH_OFFSET;
         offset < uids.length;
         offset += metadataReadBatchSize
       ) {
@@ -229,8 +234,8 @@ export class InstrumentMetadataRepository {
               ...data,
               dataRevision: {
                 increment: isDeepStrictEqual(previous?.metadata, payload) ?
-                  0 :
-                  1,
+                  UNCHANGED_REVISION_INCREMENT :
+                  REVISION_INCREMENT,
               },
             },
           });
@@ -252,8 +257,8 @@ export class InstrumentMetadataRepository {
             fetchedAt: now,
             dataRevision: {
               increment: isDeepStrictEqual(previous?.matchedUids, matchedUids) ?
-                0 :
-                1,
+                UNCHANGED_REVISION_INCREMENT :
+                REVISION_INCREMENT,
             },
           },
         });
@@ -323,7 +328,7 @@ function selectMetadata(
     dataRevision: used
       .map(
         (row) =>
-          `${row.lookup?.dataRevision ?? 0}:${row.instrument?.dataRevision ?? 0}`,
+          `${row.lookup?.dataRevision ?? MISSING_DATA_REVISION}:${row.instrument?.dataRevision ?? MISSING_DATA_REVISION}`,
       )
       .join('/'),
   };

src/integrations/tbank/tbank-access.service.ts

@@ -13,6 +13,10 @@ import { supportedTbankAccounts } from './tbank-account.policy';
 import { tbankSourceNeedsRefresh } from './tbank-source.policy';
 import { TbankTokenService } from './tbank-token.service';
 
+const EXPECTED_UPDATED_CONNECTIONS = 1;
+const MEMBERSHIP_REVISION_INCREMENT = 1;
+const UNCHANGED_MEMBERSHIP_REVISION_INCREMENT = 0;
+
 export type TbankSyncAttempt = {
   attemptId: string;
   id: string;
@@ -101,7 +105,7 @@ export class TbankAccessService {
       },
       data: { state: 'failed', errorCode: 'TBANK_UNAVAILABLE' },
     });
-    return result.count === 1;
+    return result.count === EXPECTED_UPDATED_CONNECTIONS;
   }
 
   async tokenForAttempt(attempt: TbankSyncAttempt): Promise<null | string> {
@@ -184,7 +188,7 @@ export class TbankAccessService {
         where: { userId_revision: { userId, revision } },
         data: {
           membershipAt: fetchedAt,
-          membershipRevision: { increment: changed ? 1 : 0 },
+          membershipRevision: { increment: changed ? MEMBERSHIP_REVISION_INCREMENT : UNCHANGED_MEMBERSHIP_REVISION_INCREMENT },
         },
       });
       if (completeWork) {

src/integrations/tbank/tbank-account.policy.ts

@@ -1,4 +1,4 @@
-import { MILLISECONDS_PER_SECOND } from '../../common/time';
+import { ISO_DATE_LENGTH, ISO_DATE_START, MILLISECONDS_PER_SECOND } from '../../common/time';
 import { TbankAccount } from './tbank.client';
 
 const accountTypes = {
@@ -43,5 +43,5 @@ function openedOn(seconds: number | string | undefined): null | string {
   if (seconds === undefined) return null;
   const date = new Date(Number(seconds) * MILLISECONDS_PER_SECOND);
   if (Number.isNaN(date.valueOf())) return null;
-  return date.toISOString().slice(0, 10);
+  return date.toISOString().slice(ISO_DATE_START, ISO_DATE_LENGTH);
 }

src/integrations/tbank/tbank.client.ts

@@ -30,6 +30,13 @@ import { StructuredLogger } from '../../common/logging/structured-logger.service
 import { MILLISECONDS_PER_SECOND } from '../../common/time';
 import { Environment } from '../../config/env.validation';
 
+const INITIAL_REQUEST_COUNT = 0;
+const MIN_RATE_DELAY_MS = 1;
+const FIRST_ATTEMPT = 1;
+const ATTEMPT_INCREMENT = 1;
+const NO_RPC_ATTEMPTS = 0;
+const NEXT_DAY_OFFSET = 1;
+
 const RATE_WINDOW_MS = 1_000;
 const METADATA_MAX_ATTEMPTS = 3;
 const RPC_MAX_ATTEMPTS = 2;
@@ -124,7 +131,7 @@ type TbankNamespace = {
 
 class RateLimiter {
   private readonly waiting: (() => void)[] = [];
-  private starts = 0;
+  private starts = INITIAL_REQUEST_COUNT;
   private windowStartedAt = Date.now();
 
   constructor(private readonly perSecond: number) {}
@@ -149,16 +156,16 @@ class RateLimiter {
     const now = Date.now();
     if (now - this.windowStartedAt >= RATE_WINDOW_MS) {
       this.windowStartedAt = now;
-      this.starts = 0;
+      this.starts = INITIAL_REQUEST_COUNT;
     }
     while (this.starts < this.perSecond && this.waiting.length) {
-      this.starts += 1;
+      this.starts++;
       this.waiting.shift()?.();
     }
     if (this.waiting.length && this.starts === this.perSecond) {
       setTimeout(
         () => this.drain(),
-        Math.max(1, RATE_WINDOW_MS - (now - this.windowStartedAt)),
+        Math.max(MIN_RATE_DELAY_MS, RATE_WINDOW_MS - (now - this.windowStartedAt)),
       );
     }
   }
@@ -472,7 +479,7 @@ export class TbankClient {
   ): Promise<Response> {
     const metadataCall = method === 'getInstrumentBy';
     const maxAttempts = metadataCall ? METADATA_MAX_ATTEMPTS : RPC_MAX_ATTEMPTS;
-    for (let attempts = 1; attempts <= maxAttempts; attempts += 1) {
+    for (let attempts = FIRST_ATTEMPT; attempts <= maxAttempts; attempts += ATTEMPT_INCREMENT) {
       const startedAt = performance.now();
       const queueFull = this.queue.size >= MAX_QUEUE_SIZE;
       try {
@@ -520,7 +527,7 @@ export class TbankClient {
         this.logger.event('error', 'tbank.rpc.failed', {
           operation: method,
           ...failureContext,
-          attempts: queueFull && !metadataCall ? 0 : attempts,
+          attempts: queueFull && !metadataCall ? NO_RPC_ATTEMPTS : attempts,
           durationMs: Math.round(performance.now() - startedAt),
         });
         if (
@@ -564,6 +571,6 @@ export class TbankClient {
 // Calendar owners supply inclusive UTC days; RPC timestamps use [from, next(to)).
 function utcSeconds(date: string, nextDay = false): number {
   const instant = new Date(`${date}T00:00:00Z`);
-  if (nextDay) instant.setUTCDate(instant.getUTCDate() + 1);
+  if (nextDay) instant.setUTCDate(instant.getUTCDate() + NEXT_DAY_OFFSET);
   return Math.floor(instant.valueOf() / MILLISECONDS_PER_SECOND);
 }

src/integrations/tbank/tbank.crypto.ts

@@ -1,5 +1,7 @@
 import { createCipheriv, createDecipheriv, randomBytes } from 'node:crypto';
 
+const VERSION_SIZE_BYTES = 1;
+
 const KEY_SIZE_BYTES = 32;
 
 const VERSION = 1;
@@ -34,15 +36,15 @@ export class TbankCrypto {
 
   decrypt(payload: string): string {
     const bytes = Buffer.from(payload, 'base64');
-    if (bytes[0] !== VERSION || bytes.length < 1 + NONCE_SIZE + TAG_SIZE) {
+    if (bytes[0] !== VERSION || bytes.length < VERSION_SIZE_BYTES + NONCE_SIZE + TAG_SIZE) {
       throw new Error('Invalid encrypted token');
     }
-    const nonce = bytes.subarray(1, 1 + NONCE_SIZE);
+    const nonce = bytes.subarray(VERSION_SIZE_BYTES, VERSION_SIZE_BYTES + NONCE_SIZE);
     const tag = bytes.subarray(-TAG_SIZE);
     const decipher = createDecipheriv('aes-256-gcm', this.key, nonce);
     decipher.setAuthTag(tag);
     return Buffer.concat([
-      decipher.update(bytes.subarray(1 + NONCE_SIZE, -TAG_SIZE)),
+      decipher.update(bytes.subarray(VERSION_SIZE_BYTES + NONCE_SIZE, -TAG_SIZE)),
       decipher.final(),
     ]).toString('utf8');
   }