shreyask/falcon-perception

1/*! coi-serviceworker v0.1.7 - Guido Zuidhof and contributors, licensed under MIT */2let coepCredentialless = false;3if (typeof window === 'undefined') {4    self.addEventListener("install", () => self.skipWaiting());5    self.addEventListener("activate", (event) => event.waitUntil(self.clients.claim()));6 7    self.addEventListener("message", (ev) => {8        if (!ev.data) {9            return;10        } else if (ev.data.type === "deregister") {11            self.registration12                .unregister()13                .then(() => {14                    return self.clients.matchAll();15                })16                .then(clients => {17                    clients.forEach((client) => client.navigate(client.url));18                });19        } else if (ev.data.type === "coepCredentialless") {20            coepCredentialless = ev.data.value;21        }22    });23 24    self.addEventListener("fetch", function (event) {25        const r = event.request;26        if (r.cache === "only-if-cached" && r.mode !== "same-origin") {27            return;28        }29 30        const request = (coepCredentialless && r.mode === "no-cors")31            ? new Request(r, {32                credentials: "omit",33            })34            : r;35        event.respondWith(36            fetch(request)37                .then((response) => {38                    if (response.status === 0) {39                        return response;40                    }41 42                    const newHeaders = new Headers(response.headers);43                    newHeaders.set("Cross-Origin-Embedder-Policy",44                        coepCredentialless ? "credentialless" : "require-corp"45                    );46                    if (!coepCredentialless) {47                        newHeaders.set("Cross-Origin-Resource-Policy", "cross-origin");48                    }49                    newHeaders.set("Cross-Origin-Opener-Policy", "same-origin");50 51                    return new Response(response.body, {52                        status: response.status,53                        statusText: response.statusText,54                        headers: newHeaders,55                    });56                })57                .catch((e) => console.error(e))58        );59    });60 61} else {62    (() => {63        const reloadedBySelf = window.sessionStorage.getItem("coiReloadedBySelf");64        window.sessionStorage.removeItem("coiReloadedBySelf");65        const coepDegrading = (reloadedBySelf == "coepdegrade");66 67        // You can customize the behavior of this script through a global `coi` variable.68        const coi = {69            shouldRegister: () => !reloadedBySelf,70            shouldDeregister: () => false,71            coepCredentialless: () => true,72            coepDegrade: () => true,73            doReload: () => window.location.reload(),74            quiet: false,75            ...window.coi76        };77 78        const n = navigator;79        const controlling = n.serviceWorker && n.serviceWorker.controller;80 81        // Record the failure if the page is served by serviceWorker.82        if (controlling && !window.crossOriginIsolated) {83            window.sessionStorage.setItem("coiCoepHasFailed", "true");84        }85        const coepHasFailed = window.sessionStorage.getItem("coiCoepHasFailed");86 87        if (controlling) {88            // Reload only on the first failure.89            const reloadToDegrade = coi.coepDegrade() && !(90                coepDegrading || window.crossOriginIsolated91            );92            n.serviceWorker.controller.postMessage({93                type: "coepCredentialless",94                value: (reloadToDegrade || coepHasFailed && coi.coepDegrade())95                    ? false96                    : coi.coepCredentialless(),97            });98            if (reloadToDegrade) {99                !coi.quiet && console.log("Reloading page to degrade COEP.");100                window.sessionStorage.setItem("coiReloadedBySelf", "coepdegrade");101                coi.doReload("coepdegrade");102            }103 104            if (coi.shouldDeregister()) {105                n.serviceWorker.controller.postMessage({ type: "deregister" });106            }107        }108 109        // If we're already coi: do nothing. Perhaps it's due to this script doing its job, or COOP/COEP are110        // already set from the origin server. Also if the browser has no notion of crossOriginIsolated, just give up here.111        if (window.crossOriginIsolated !== false || !coi.shouldRegister()) return;112 113        if (!window.isSecureContext) {114            !coi.quiet && console.log("COOP/COEP Service Worker not registered, a secure context is required.");115            return;116        }117 118        // In some environments (e.g. Firefox private mode) this won't be available119        if (!n.serviceWorker) {120            !coi.quiet && console.error("COOP/COEP Service Worker not registered, perhaps due to private mode.");121            return;122        }123 124        n.serviceWorker.register(window.document.currentScript.src).then(125            (registration) => {126                !coi.quiet && console.log("COOP/COEP Service Worker registered", registration.scope);127 128                registration.addEventListener("updatefound", () => {129                    !coi.quiet && console.log("Reloading page to make use of updated COOP/COEP Service Worker.");130                    window.sessionStorage.setItem("coiReloadedBySelf", "updatefound");131                    coi.doReload();132                });133 134                // If the registration is active, but it's not controlling the page135                if (registration.active && !n.serviceWorker.controller) {136                    !coi.quiet && console.log("Reloading page to make use of COOP/COEP Service Worker.");137                    window.sessionStorage.setItem("coiReloadedBySelf", "notcontrolling");138                    coi.doReload();139                }140            },141            (err) => {142                !coi.quiet && console.error("COOP/COEP Service Worker failed to register:", err);143            }144        );145    })();146}147