unignore /lib

.gitignore

@@ -1,3 +1,3 @@
 coverage/
-lib/
+dist/
 node_modules/

src/lib/csp.ts

@@ -0,0 +1,65 @@
+import {
+  getCSP,
+  nonce,
+  CSPDirectives,
+} from "csp-header";
+import { type CSP, type CSPHeaderConfig } from "../types.js";
+import { DEV_DEFAULT_CSP, PROD_DEFAULT_CSP } from "../defaults.js";
+
+const cspNonceDirectives = [
+  "script-src",
+  "style-src",
+  "img-src",
+  "font-src",
+  "media-src",
+  "object-src",
+  "default-src",
+] as const;
+
+const DEFAULT_CSP: CSPHeaderConfig = {
+  prod: {
+    withNonce: true,
+    value: PROD_DEFAULT_CSP,
+    cspBlock: false,
+    cspReportOnly: true,
+  },
+  dev: {
+    withNonce: true,
+    value: DEV_DEFAULT_CSP,
+    cspBlock: true,
+    cspReportOnly: false,
+  },
+};
+
+export const addNonceToDirectives = (
+  userDefinedCSP: CSP["value"],
+  nonceString: string
+): CSP["value"] => {
+  const csp: Partial<CSPDirectives> = {
+    ...DEFAULT_CSP.prod.value,
+    ...userDefinedCSP,
+  };
+
+  cspNonceDirectives.forEach((directive) => {
+    if (csp[directive] && Array.isArray(csp[directive])) {
+      csp[directive].push(nonce(nonceString));
+    }
+  });
+
+  return csp;
+};
+
+export function generateCSP(cspOptions: CSP["value"], nonceString?: string) {
+  const directives = nonceString ? addNonceToDirectives(cspOptions, nonceString) : cspOptions;
+
+  if (Object.prototype.hasOwnProperty.call(directives,"report-uri")) {
+    const reportUri = directives["report-uri"];
+    delete directives["report-uri"];
+
+    return getCSP({ directives, reportUri }) as string;
+  } else {
+    return getCSP({
+      directives,
+    }) as string;
+  }
+}

src/lib/hsts.ts

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+interface Params {
+  includeSubDomains?: boolean;
+  preload?: boolean;
+  maxAge: number;
+}
+
+export function hsts({
+  includeSubDomains = true,
+  preload = true,
+  maxAge = 31536000 /* 1year */,
+}: Params) {
+  return `max-age=${String(maxAge)};${includeSubDomains ? " includeSubDomains;" : ""}${
+    preload ? " preload" : ""
+  }`;
+}

src/lib/permissions-policy.ts

@@ -0,0 +1,20 @@
+interface HardwarePermissions {
+  camera?: string;
+  microphone?: string;
+  geolocation?: string;
+  payment?: string;
+}
+
+export function permissionsPolicy(perms: HardwarePermissions) {
+  const headerValue: string[] = [];
+
+  for (const [key, value] of Object.entries(perms)) {
+    if (typeof value === "string") {
+      headerValue.push(`${key}=${value}`);
+    }
+  }
+
+  // headerValue = ["camera=()", "microphone=()"]
+  return headerValue.join(", ");
+  // "camera=(), microfone=()"
+}