rename current to used, tweak types

Author: nfriedly

source/index.ts

@@ -1,6 +1 @@
-export { parseRateLimit } from './ratelimit-header-parser'
-export {
-    RateLimit,
-    RateLimitOptions,
-    ResponseOrHeadersObject
-} from './types'
+export { parseRateLimit } from './ratelimit-header-parser'

source/ratelimit-header-parser.ts

@@ -1,11 +1,14 @@
-import { isModuleNamespaceObject } from 'node:util/types'
-import {
-    HeadersObject,
+import type { ServerResponse, IncomingHttpHeaders, OutgoingHttpHeaders } from 'node:http'
+import type {
     RateLimit,
     RateLimitOptions,
-    ResponseOrHeadersObject
 } from './types'
 
+// node or fetch
+export type ResponseObject = ServerResponse | Response; 
+export type HeadersObject =  IncomingHttpHeaders | OutgoingHttpHeaders | Headers | Object;
+export type ResponseOrHeadersObject = ResponseObject | HeadersObject;
+
 export function parseRateLimit(input: ResponseOrHeadersObject, options?: RateLimitOptions): RateLimit | undefined {
     if ('headers' in input && typeof input.headers === 'object' && !Array.isArray(input.headers)) {
         return parseHeadersObject(input.headers, options)
@@ -39,8 +42,10 @@ function parseHeadersObject(input: HeadersObject, options: RateLimitOptions | un
 
     const limit = num(getHeader(input, `${prefix}limit`))
     // used - https://github.com/reddit-archive/reddit/wiki/API#rules
+    // used - https://docs.github.com/en/rest/overview/resources-in-the-rest-api?apiVersion=2022-11-28#rate-limit-headers
     // observed - https://docs.gitlab.com/ee/administration/settings/user_and_ip_rate_limits.html#response-headers
-    const current = num(getHeader(input, `${prefix}used`)) || num(getHeader(input, `${prefix}observed`))
+    // note that || is valid here because used should always be at least 1, and || handles NaN correctly, whereas ?? doesn't
+    const used = num(getHeader(input, `${prefix}used`)) || num(getHeader(input, `${prefix}observed`))
     const remaining = num(getHeader(input, `${prefix}remaining`))
 
     let reset: Date|undefined = undefined;
@@ -60,8 +65,8 @@ function parseHeadersObject(input: HeadersObject, options: RateLimitOptions | un
     }
 
     return {
-        limit: isNaN(limit) ? current + remaining : limit, // reddit omits
-        current: isNaN(current) ? limit - remaining : current, // most omit
+        limit: isNaN(limit) ? used + remaining : limit, // reddit omits
+        used: isNaN(used) ? limit - remaining : used, // most omit
         remaining,
         reset
     }
@@ -77,7 +82,7 @@ export function parseCombinedRateLimitHeader(input: string): RateLimit {
     const reset = secondsToDate(resetSeconds);
     return {
         limit,
-        current: limit - remaining,
+        used: limit - remaining,
         remaining,
         reset,
     }

source/types.ts

@@ -1,8 +1,6 @@
-import type { ServerResponse, IncomingHttpHeaders, OutgoingHttpHeaders } from 'node:http'
-
 export type RateLimit = {
     limit: number,
-    current: number,
+    used: number,
     remaining: number,
     reset?: Date,
     // todo: policy
@@ -11,8 +9,3 @@ export type RateLimit = {
 export type RateLimitOptions = {
     reset?: 'date' | 'unix' | 'seconds' | 'milliseconds',
 }
-
-// node or fetch
-export type ResponseObject = ServerResponse | Response; 
-export type HeadersObject =  IncomingHttpHeaders | OutgoingHttpHeaders | Headers | Object;
-export type ResponseOrHeadersObject = ResponseObject | HeadersObject;

test/parser-test.ts

@@ -11,7 +11,7 @@ describe('parseRateLimitHeaders', () => {
         expect(parseRateLimit(headers)).toMatchObject({
             limit: 100,
             remaining: 70,
-            current: 30,
+            used: 30,
             reset: expect.any(Date) // todo: mock the clock, then match to a specific date
         })
     })
@@ -27,7 +27,7 @@ describe('parseCombinedRateLimitHeader', () => {
         expect(parseCombinedRateLimitHeader('limit=100, remaining=25, reset=5')).toMatchObject({
             limit: 100,
             remaining: 25,
-            current: 75,
+            used: 75,
             reset: expect.any(Date) // todo: mock the clock, then match to a specific date
         })
     })