refactor(http-recorder): Redactor + Recorder seams, README (#26636)

packages/http-recorder/src/redactor.ts

@@ -0,0 +1,76 @@
+import { Option } from "effect"
+import { decodeJson } from "./matching"
+import { redactHeaders, redactUrl } from "./redaction"
+import type { RequestSnapshot, ResponseSnapshot } from "./schema"
+
+export const DEFAULT_REQUEST_HEADERS: ReadonlyArray<string> = ["content-type", "accept", "openai-beta"]
+export const DEFAULT_RESPONSE_HEADERS: ReadonlyArray<string> = ["content-type"]
+
+const identity = <T>(value: T) => value
+
+export interface Redactor {
+  readonly request: (snapshot: RequestSnapshot) => RequestSnapshot
+  readonly response: (snapshot: ResponseSnapshot) => ResponseSnapshot
+}
+
+export const compose = (...redactors: ReadonlyArray<Partial<Redactor>>): Redactor => {
+  const requests = redactors.map((r) => r.request).filter((fn): fn is Redactor["request"] => fn !== undefined)
+  const responses = redactors.map((r) => r.response).filter((fn): fn is Redactor["response"] => fn !== undefined)
+  return {
+    request: requests.length === 0 ? identity : (snapshot) => requests.reduce((acc, fn) => fn(acc), snapshot),
+    response: responses.length === 0 ? identity : (snapshot) => responses.reduce((acc, fn) => fn(acc), snapshot),
+  }
+}
+
+export interface HeaderOptions {
+  readonly allow?: ReadonlyArray<string>
+  readonly redact?: ReadonlyArray<string>
+}
+
+export const requestHeaders = (options: HeaderOptions = {}): Partial<Redactor> => ({
+  request: (snapshot) => ({
+    ...snapshot,
+    headers: redactHeaders(snapshot.headers, options.allow ?? DEFAULT_REQUEST_HEADERS, options.redact),
+  }),
+})
+
+export const responseHeaders = (options: HeaderOptions = {}): Partial<Redactor> => ({
+  response: (snapshot) => ({
+    ...snapshot,
+    headers: redactHeaders(snapshot.headers, options.allow ?? DEFAULT_RESPONSE_HEADERS, options.redact),
+  }),
+})
+
+export interface UrlOptions {
+  readonly query?: ReadonlyArray<string>
+  readonly transform?: (url: string) => string
+}
+
+export const url = (options: UrlOptions = {}): Partial<Redactor> => ({
+  request: (snapshot) => ({ ...snapshot, url: redactUrl(snapshot.url, options.query, options.transform) }),
+})
+
+export const body = (transform: (parsed: unknown) => unknown): Partial<Redactor> => ({
+  request: (snapshot) => ({
+    ...snapshot,
+    body: Option.match(decodeJson(snapshot.body), {
+      onNone: () => snapshot.body,
+      onSome: (parsed) => JSON.stringify(transform(parsed)),
+    }),
+  }),
+})
+
+export interface DefaultRedactorOverrides {
+  readonly requestHeaders?: HeaderOptions
+  readonly responseHeaders?: HeaderOptions
+  readonly url?: UrlOptions
+  readonly body?: (parsed: unknown) => unknown
+}
+
+export const defaults = (overrides: DefaultRedactorOverrides = {}): Redactor =>
+  compose(
+    requestHeaders(overrides.requestHeaders),
+    responseHeaders(overrides.responseHeaders),
+    url(overrides.url),
+    ...(overrides.body ? [body(overrides.body)] : []),
+  )