Create cookies.js polyfill for document contexts

This is also a design sketch for the new API and is loosely based on/inspired by w3c/ServiceWorker#707

cookies.js

@@ -0,0 +1,125 @@
+(function() {
+  "use strict";
+  if (navigator.cookies) return;
+  class CookieJar {
+    constructor(document, defSecure, defReadPath) {
+      this.doc_ = document;
+      this.defSecure_ = defSecure;
+      this.defReadPath_ = defReadPath;
+    }
+    has(name, path) {
+      return this.getAll(name, path).then(x=>x.length);
+    }
+    get(name, path) {
+      if (path != null && path !== this.defReadPath_) {
+        // TODO: iframe with unpredictable long pathname inside
+        // requested path, maybe by appending as many
+        // randomly-selected '$' and ':' as needed to reach 2083 chars
+        // in the URL
+        throw new Error('Cannot read cookies from requested path ' + JSON.stringify(path) + ' from path ' + JSON.stringify(this.defReadPath_) + ': not yet implemented.');
+      }
+      return this.getAll(name, path).then(allCookies => {
+        if (name != null) return allCookies[0];
+        return allCookies.reduce((r,nc) => {
+          if (!r.hasOwnProperty(nc.name)) r[nc.name] = nc.value;
+          return r;
+        }, {});
+      });
+    }
+    getAll(name, path) {
+      if (name != null) name = String(name);
+      if (name != null && name.indexOf(';') !== -1) throw new Error('Character ";" is not allowed in cookie name');
+      if (name != null && name.indexOf('=') !== -1) throw new Error('Character "=" is not allowed in cookie name');
+      if (name && name.match(/[()<>@,;:\\""\/\[\]?={} \0-\x1f\x7f]|[^\x21-\x7e]/)) {
+        // Does not match document.cookie behavior!
+        throw new Error('Unsupported character in cookie name');
+      }
+      return new Promise((ok, fail) => {
+        let allValues = [];
+        try {
+          let jar = String(document.cookie || '');
+          for (let i = 0, j = jar.length, k = jar.indexOf(';');
+               k = (k == -1) ? j : k, i < j;
+               i = k + 1 + (jar[k + 1] == ' ' ? 1 : 0), k = jar.indexOf(';', i)) {
+            let nv = jar.substr(i, k - i), c = nv.indexOf('=');
+            if (c !== -1) {
+              let n = nv.substr(0, c);
+              if (name == null || name === n) {
+                let v = nv.substr(c + 1);
+                if (name == null) allValues.push({name: n, value: v});
+                else allValues.push(v);
+              }
+            }
+          }
+          ok(allValues);
+        } catch (x) {
+          fail(x);
+        }
+      });
+    }
+    delete(name, options) {
+      return this.set(name, undefined, options);
+    }
+    set(name, value, options) {
+      name = String(name || '') || undefined;
+      if (!name) throw new Error('Cookie name is required');
+      if (name.match(/[()<>@,;:\\""\/\[\]?={} \0-\x1f\x7f]|[^\x21-\x7e]/)) {
+        // Does not match document.cookie behavior!
+        throw new Error('Unsupported character in cookie name');
+      }
+      options = options || {};
+      let expires = String(options.expires || '') || undefined;
+      if (expires && expires.indexOf(';') !== -1) throw new Error('Character ";" is not allowed in cookie "expires" attribute');
+      let maxAge = options.maxAge;
+      if (maxAge != null) maxAge = maxAge | 0;
+      let domain = String(options.domain || '') || undefined;
+      if (domain && domain.indexOf(';') !== -1) throw new Error('Character ";" is not allowed in cookie "domain" attribute');
+      let path = String(options.path || '/');
+      if (path && path.indexOf(';') !== -1) throw new Error('Character ";" is not allowed in cookie "path" attribute');
+      let secure = options.secure;
+      if (secure == null) secure = this.defSecure_;
+      secure = !!secure;
+      let httpOnly = !!options.httpOnly;
+      if (value == null && maxAge == null && expires == null) maxAge = 0;
+      value = String(value || '');
+      if (value.match(/[^\x2D-\x3A\x21\x23-\x2B\x3C-\x5B\x5D-\x7E]/)) {
+        // Does not match document.cookie behavior!
+        throw new Error('Unsupported character in cookie value');
+      }
+      let setCookieParts = [name, '=', value];
+      if (domain != null) setCookieParts.push('; domain=', domain);
+      if (path != null) setCookieParts.push('; path=', path);
+      if (expires != null) setCookieParts.push('; expires=', expires);
+      if (maxAge != null) setCookieParts.push('; max-age=', maxAge);
+      if (secure) setCookieParts.push('; secure');
+      if (httpOnly) setCookieParts.push('; httpOnly');
+      for (let k in options) {
+        if (!Object.prototype.hasOwnProperty.call(options, k)) continue;
+        let v = options[k];
+        if (typeof(v) === 'function') continue;
+        if (k.indexOf(';') != -1) throw new Error('Character ";" is not allowed in cookie extended attribute name: ' + JSON.stringify(k));
+        if (k.indexOf('=') != -1) throw new Error('Character "=" is not allowed in cookie extended attribute name: ' + JSON.stringify(k));
+        if (k !== k.replace(/^[ \t]*([^ \t](.*[^ \t])?)\s*$/, '$1')) throw new Error('Cookie extended attribute name cannot begin or end with whitespace');
+        let ck = k.replace(/-([a-z])/g, x => x[1].toUpperCase());
+        if (k != ck) throw new Error('Use camel-case in attribute names: ' + JSON.stringify(k));
+        if (k.match(/^expires|maxAge|domain|path|secure|httpOnly$/)) continue;
+        if (v != null) v = String(v);
+        if (v && v.indexOf(';') != -1) throw new Error('Character ";" is not allowed in cookie extended attribute ' + JSON.stringify(k) + ' value: ' + JSON.stringify(v));
+        if (v && v !== v.replace(/^[ \t]*([^ \t](.*[^ \t])?)\s*$/, '$1')) throw new Error('Cookie extended attribute value cannot begin or end with whitespace');
+        setCookieParts.push('; ', k);
+        if (v != null) setCookieParts.push('=', v);
+      }
+      let setCookie = setCookieParts.join('');
+      return new Promise((ok, fail) => {
+        try {
+	  console.log('Set-Cookie: %s', setCookie);
+          document.cookie = setCookie;
+          ok();
+        } catch(x) {
+          fail(x);
+        }
+      });
+    }
+  };
+  navigator.cookies = new CookieJar(self.document, location.protocol === 'https:', String(location.pathname.replace(/[^\/]*$/, '')));
+})();