Merge branch 'master' of git+ssh://taler.net/var/git/wallet-webex

11 files changed, 284 insertions, 170 deletions

diff --git a/lib/wallet/checkable.ts b/lib/wallet/checkable.ts
index a35634e81..9fd816578 100644
--- a/lib/wallet/checkable.ts
+++ b/lib/wallet/checkable.ts
@@ -25,18 +25,39 @@
  */
 
 export namespace Checkable {
-  export function SchemaError(message) {
+
+  type Path = (number|string)[];
+
+  interface SchemaErrorConstructor {
+    new (err: string): SchemaError;
+  }
+
+  interface SchemaError {
+    name: string;
+    message: string;
+  }
+
+  interface Prop {
+    propertyKey: any;
+    checker: any;
+    type: any;
+    elementChecker?: any;
+    elementProp?: any;
+  }
+
+  export let SchemaError = (function SchemaError(message: string) {
     this.name = 'SchemaError';
     this.message = message;
     this.stack = (<any>new Error()).stack;
-  }
+  }) as any as SchemaErrorConstructor;
+
 
   SchemaError.prototype = new Error;
 
   let chkSym = Symbol("checkable");
 
 
-  function checkNumber(target, prop, path): any {
+  function checkNumber(target: any, prop: Prop, path: Path): any {
     if ((typeof target) !== "number") {
       throw new SchemaError(`expected number for ${path}`);
     }
@@ -44,7 +65,7 @@ export namespace Checkable {
   }
 
 
-  function checkString(target, prop, path): any {
+  function checkString(target: any, prop: Prop, path: Path): any {
     if (typeof target !== "string") {
       throw new SchemaError(`expected string for ${path}, got ${typeof target} instead`);
     }
@@ -52,7 +73,7 @@ export namespace Checkable {
   }
 
 
-  function checkAnyObject(target, prop, path): any {
+  function checkAnyObject(target: any, prop: Prop, path: Path): any {
     if (typeof target !== "object") {
       throw new SchemaError(`expected (any) object for ${path}, got ${typeof target} instead`);
     }
@@ -60,12 +81,12 @@ export namespace Checkable {
   }
 
 
-  function checkAny(target, prop, path): any {
+  function checkAny(target: any, prop: Prop, path: Path): any {
     return target;
   }
 
 
-  function checkList(target, prop, path): any {
+  function checkList(target: any, prop: Prop, path: Path): any {
     if (!Array.isArray(target)) {
       throw new SchemaError(`array expected for ${path}, got ${typeof target} instead`);
     }
@@ -77,7 +98,7 @@ export namespace Checkable {
   }
 
 
-  function checkOptional(target, prop, path): any {
+  function checkOptional(target: any, prop: Prop, path: Path): any {
     console.assert(prop.propertyKey);
     prop.elementChecker(target,
                         prop.elementProp,
@@ -86,7 +107,7 @@ export namespace Checkable {
   }
 
 
-  function checkValue(target, prop, path): any {
+  function checkValue(target: any, prop: Prop, path: Path): any {
     let type = prop.type;
     if (!type) {
       throw Error(`assertion failed (prop is ${JSON.stringify(prop)})`);
@@ -123,8 +144,8 @@ export namespace Checkable {
   }
 
 
-  export function Class(target) {
-    target.checked = (v) => {
+  export function Class(target: any) {
+    target.checked = (v: any) => {
       return checkValue(v, {
         propertyKey: "(root)",
         type: target,
@@ -135,7 +156,7 @@ export namespace Checkable {
   }
 
 
-  export function Value(type) {
+  export function Value(type: any) {
     if (!type) {
       throw Error("Type does not exist yet (wrong order of definitions?)");
     }
@@ -152,7 +173,7 @@ export namespace Checkable {
   }
 
 
-  export function List(type) {
+  export function List(type: any) {
     let stub = {};
     type(stub, "(list-element)");
     let elementProp = mkChk(stub).props[0];
@@ -174,7 +195,7 @@ export namespace Checkable {
   }
 
 
-  export function Optional(type) {
+  export function Optional(type: any) {
     let stub = {};
     type(stub, "(optional-element)");
     let elementProp = mkChk(stub).props[0];
@@ -230,7 +251,7 @@ export namespace Checkable {
   }
 
 
-  function mkChk(target) {
+  function mkChk(target: any) {
     let chk = target[chkSym];
     if (!chk) {
       chk = {props: []};
diff --git a/lib/wallet/cryptoApi.ts b/lib/wallet/cryptoApi.ts
index a0113b2ea..2a2a7d319 100644
--- a/lib/wallet/cryptoApi.ts
+++ b/lib/wallet/cryptoApi.ts
@@ -27,9 +27,10 @@ import {Denomination} from "./types";
 import {Offer} from "./wallet";
 import {CoinWithDenom} from "./wallet";
 import {PayCoinInfo} from "./types";
+type RegistryEntry = {resolve: any; reject: any};
 export class CryptoApi {
   private nextRpcId: number = 1;
-  private rpcRegistry = {};
+  private rpcRegistry: {[n: number]: RegistryEntry} = {};
   private cryptoWorker: Worker;
 
 
@@ -52,14 +53,14 @@ export class CryptoApi {
   }
 
 
-  private registerRpcId(resolve, reject): number {
+  private registerRpcId(resolve: any, reject: any): number {
     let id = this.nextRpcId++;
     this.rpcRegistry[id] = {resolve, reject};
     return id;
   }
 
 
-  private doRpc<T>(methodName: string, ...args): Promise<T> {
+  private doRpc<T>(methodName: string, ...args: any[]): Promise<T> {
     return new Promise<T>((resolve, reject) => {
       let msg = {
         operation: methodName,
diff --git a/lib/wallet/cryptoLib.ts b/lib/wallet/cryptoLib.ts
index 1acbdaa16..1ca7b856f 100644
--- a/lib/wallet/cryptoLib.ts
+++ b/lib/wallet/cryptoLib.ts
@@ -28,6 +28,7 @@ import {Offer} from "./wallet";
 import {CoinWithDenom} from "./wallet";
 import {CoinPaySig} from "./types";
 import {Denomination} from "./types";
+import {Amount} from "./emscriptif";
 
 
 export function main(worker: Worker) {
@@ -43,7 +44,7 @@ export function main(worker: Worker) {
     if (typeof msg.data.operation != "string") {
       console.error("RPC operation must be string");
     }
-    let f = RpcFunctions[msg.data.operation];
+    let f = (RpcFunctions as any)[msg.data.operation];
     if (!f) {
       console.error(`unknown operation: '${msg.data.operation}'`);
       return;
@@ -156,7 +157,7 @@ namespace RpcFunctions {
   }
 
 
-  export function rsaUnblind(sig, bk, pk): string {
+  export function rsaUnblind(sig: string, bk: string, pk: string): string {
     let denomSig = native.rsaUnblind(native.RsaSignature.fromCrock(sig),
                                      native.RsaBlindingKeySecret.fromCrock(bk),
                                      native.RsaPublicKey.fromCrock(pk));
@@ -170,11 +171,11 @@ namespace RpcFunctions {
    */
   export function signDeposit(offer: Offer,
                               cds: CoinWithDenom[]): PayCoinInfo {
-    let ret = [];
+    let ret: PayCoinInfo = [];
     let amountSpent = native.Amount.getZero(cds[0].coin.currentAmount.currency);
     let amountRemaining = new native.Amount(offer.contract.amount);
     for (let cd of cds) {
-      let coinSpend;
+      let coinSpend: Amount;
 
       if (amountRemaining.value == 0 && amountRemaining.fraction == 0) {
         break;
diff --git a/lib/wallet/db.ts b/lib/wallet/db.ts
index 6cd25ee27..5104f28fb 100644
--- a/lib/wallet/db.ts
+++ b/lib/wallet/db.ts
@@ -15,6 +15,7 @@
  */
 
 "use strict";
+import Dictionary = _.Dictionary;
 
 /**
  * Declarations and helpers for
@@ -83,27 +84,27 @@ export function openTalerDb(): Promise<IDBDatabase> {
 }
 
 
-export function exportDb(db): Promise<any> {
+export function exportDb(db: IDBDatabase): Promise<any> {
   let dump = {
     name: db.name,
     version: db.version,
-    stores: {}
+    stores: {} as Dictionary<any>,
   };
 
   return new Promise((resolve, reject) => {
 
-    let tx = db.transaction(db.objectStoreNames);
-    tx.addEventListener("complete", (e) => {
+    let tx = db.transaction(Array.from(db.objectStoreNames));
+    tx.addEventListener("complete", () => {
       resolve(dump);
     });
     for (let i = 0; i < db.objectStoreNames.length; i++) {
       let name = db.objectStoreNames[i];
-      let storeDump = {};
+      let storeDump = {} as Dictionary<any>;
       dump.stores[name] = storeDump;
       let store = tx.objectStore(name)
                     .openCursor()
-                    .addEventListener("success", (e) => {
-                      let cursor = e.target.result;
+                    .addEventListener("success", (e: Event) => {
+                      let cursor = (e.target as any).result;
                       if (cursor) {
                         storeDump[cursor.key] = cursor.value;
                         cursor.continue();
diff --git a/lib/wallet/emscriptif.ts b/lib/wallet/emscriptif.ts
index 8540d15d0..1e5fb0283 100644
--- a/lib/wallet/emscriptif.ts
+++ b/lib/wallet/emscriptif.ts
@@ -36,11 +36,11 @@ const GNUNET_SYSERR = -1;
 
 let Module = EmscWrapper.Module;
 
-let getEmsc: EmscWrapper.EmscFunGen = (...args) => Module.cwrap.apply(null,
+let getEmsc: EmscWrapper.EmscFunGen = (...args: any[]) => Module.cwrap.apply(null,
                                                                       args);
 
 var emsc = {
-  free: (ptr) => Module._free(ptr),
+  free: (ptr: number) => Module._free(ptr),
   get_value: getEmsc('TALER_WR_get_value',
                      'number',
                      ['number']),
@@ -164,13 +164,12 @@ enum RandomQuality {
 
 
 abstract class ArenaObject {
-  private _nativePtr: number;
+  protected _nativePtr: number | undefined = undefined;
   arena: Arena;
 
   abstract destroy(): void;
 
   constructor(arena?: Arena) {
-    this.nativePtr = null;
     if (!arena) {
       if (arenaStack.length == 0) {
         throw Error("No arena available")
@@ -192,14 +191,14 @@ abstract class ArenaObject {
   }
 
   free() {
-    if (this.nativePtr !== undefined) {
+    if (this.nativePtr) {
       emsc.free(this.nativePtr);
-      this.nativePtr = undefined;
+      this._nativePtr = undefined;
     }
   }
 
   alloc(size: number) {
-    if (this.nativePtr !== undefined) {
+    if (this._nativePtr !== undefined) {
       throw Error("Double allocation");
     }
     this.nativePtr = emscAlloc.malloc(size);
@@ -212,21 +211,22 @@ abstract class ArenaObject {
     this._nativePtr = n;
   }
 
-  set nativePtr(v) {
+  set nativePtr(v: number) {
     this.setNative(v);
   }
 
   get nativePtr() {
     return this.getNative();
   }
-
 }
 
+
 interface Arena {
   put(obj: ArenaObject): void;
   destroy(): void;
 }
 
+
 class DefaultArena implements Arena {
   heap: Array<ArenaObject>;
 
@@ -234,7 +234,7 @@ class DefaultArena implements Arena {
     this.heap = [];
   }
 
-  put(obj) {
+  put(obj: ArenaObject) {
     this.heap.push(obj);
   }
 
@@ -269,7 +269,7 @@ class SyncArena extends DefaultArena {
     super();
   }
 
-  pub(obj) {
+  pub(obj: ArenaObject) {
     super.put(obj);
     if (!this.isScheduled) {
       this.schedule();
@@ -308,14 +308,12 @@ export class Amount extends ArenaObject {
   }
 
   destroy() {
-    if (this.nativePtr != 0) {
-      emsc.free(this.nativePtr);
-    }
+    super.free();
   }
 
 
   static getZero(currency: string, a?: Arena): Amount {
-    let am = new Amount(null, a);
+    let am = new Amount(undefined, a);
     let r = emsc.amount_get_zero(currency, am.getNative());
     if (r != GNUNET_OK) {
       throw Error("invalid currency");
@@ -442,7 +440,8 @@ abstract class PackedArenaObject extends ArenaObject {
   }
 
   alloc() {
-    if (this.nativePtr === null) {
+    // FIXME: should the client be allowed to call alloc multiple times?
+    if (!this._nativePtr) {
       this.nativePtr = emscAlloc.malloc(this.size());
     }
   }
@@ -466,7 +465,7 @@ abstract class PackedArenaObject extends ArenaObject {
       b = (b + 256) % 256;
       bytes.push("0".concat(b.toString(16)).slice(-2));
     }
-    let lines = [];
+    let lines: string[] = [];
     for (let i = 0; i < bytes.length; i += 8) {
       lines.push(bytes.slice(i, i + 8).join(","));
     }
@@ -482,7 +481,7 @@ export class AmountNbo extends PackedArenaObject {
 
   toJson(): any {
     let a = new DefaultArena();
-    let am = new Amount(null, a);
+    let am = new Amount(undefined, a);
     am.fromNbo(this);
     let json = am.toJson();
     a.destroy();
@@ -508,7 +507,7 @@ export class EddsaPrivateKey extends PackedArenaObject {
     return obj;
   }
 
-  static fromCrock: (string) => EddsaPrivateKey;
+  static fromCrock: (s: string) => EddsaPrivateKey;
 }
 mixinStatic(EddsaPrivateKey, fromCrock);
 
@@ -521,7 +520,7 @@ function fromCrock(s: string) {
 }
 
 
-function mixin(obj, method, name?: string) {
+function mixin(obj: any, method: any, name?: string) {
   if (!name) {
     name = method.name;
   }
@@ -532,7 +531,7 @@ function mixin(obj, method, name?: string) {
 }
 
 
-function mixinStatic(obj, method, name?: string) {
+function mixinStatic(obj: any, method: any, name?: string) {
   if (!name) {
     name = method.name;
   }
@@ -595,7 +594,7 @@ export class RsaBlindingKeySecret extends PackedArenaObject {
     return o;
   }
 
-  static fromCrock: (string) => RsaBlindingKeySecret;
+  static fromCrock: (s: string) => RsaBlindingKeySecret;
 }
 mixinStatic(RsaBlindingKeySecret, fromCrock);
 
@@ -622,9 +621,9 @@ export class ByteArray extends PackedArenaObject {
     return this.allocatedSize;
   }
 
-  constructor(desiredSize: number, init: number, a?: Arena) {
+  constructor(desiredSize: number, init?: number, a?: Arena) {
     super(a);
-    if (init === undefined || init === null) {
+    if (init === undefined) {
       this.nativePtr = emscAlloc.malloc(desiredSize);
     } else {
       this.nativePtr = init;
@@ -642,7 +641,7 @@ export class ByteArray extends PackedArenaObject {
     let hstr = emscAlloc.malloc(s.length + 1);
     Module.writeStringToMemory(s, hstr);
     let decodedLen = Math.floor((s.length * 5) / 8);
-    let ba = new ByteArray(decodedLen, null, a);
+    let ba = new ByteArray(decodedLen, undefined, a);
     let res = emsc.string_to_data(hstr, s.length, ba.nativePtr, decodedLen);
     emsc.free(hstr);
     if (res != GNUNET_OK) {
@@ -777,7 +776,7 @@ export class AbsoluteTimeNbo extends PackedArenaObject {
     x.alloc();
     let r = /Date\(([0-9]+)\)/;
     let m = r.exec(s);
-    if (m.length != 2) {
+    if (!m || m.length != 2) {
       throw Error();
     }
     let n = parseInt(m[1]) * 1000000;
@@ -899,11 +898,11 @@ interface Encodeable {
   encode(arena?: Arena): ByteArray;
 }
 
-function makeEncode(encodeFn) {
+function makeEncode(encodeFn: any) {
   function encode(arena?: Arena) {
     let ptr = emscAlloc.malloc(PTR_SIZE);
     let len = encodeFn(this.getNative(), ptr);
-    let res = new ByteArray(len, null, arena);
+    let res = new ByteArray(len, undefined, arena);
     res.setNative(Module.getValue(ptr, '*'));
     emsc.free(ptr);
     return res;
diff --git a/lib/wallet/helpers.ts b/lib/wallet/helpers.ts
index fd1650758..5d231fe64 100644
--- a/lib/wallet/helpers.ts
+++ b/lib/wallet/helpers.ts
@@ -24,7 +24,7 @@
 
 import {AmountJson} from "./types";
 
-export function substituteFulfillmentUrl(url: string, vars) {
+export function substituteFulfillmentUrl(url: string, vars: any) {
   url = url.replace("${H_contract}", vars.H_contract);
   url = url.replace("${$}", "$");
   return url;
@@ -42,7 +42,7 @@ export function amountToPretty(amount: AmountJson): string {
  *
  * See http://api.taler.net/wallet.html#general
  */
-export function canonicalizeBaseUrl(url) {
+export function canonicalizeBaseUrl(url: string) {
   let x = new URI(url);
   if (!x.protocol()) {
     x.protocol("https");
@@ -54,10 +54,10 @@ export function canonicalizeBaseUrl(url) {
 }
 
 
-export function parsePrettyAmount(pretty: string): AmountJson {
+export function parsePrettyAmount(pretty: string): AmountJson|undefined {
   const res = /([0-9]+)(.[0-9]+)?\s*(\w+)/.exec(pretty);
   if (!res) {
-    return null;
+    return undefined;
   }
   return {
     value: parseInt(res[1], 10),
diff --git a/lib/wallet/http.ts b/lib/wallet/http.ts
index 60f388e4b..8f82ceaff 100644
--- a/lib/wallet/http.ts
+++ b/lib/wallet/http.ts
@@ -66,19 +66,19 @@ export class BrowserHttpLib {
   }
 
 
-  postJson(url: string|uri.URI, body) {
+  postJson(url: string|uri.URI, body: any) {
     return this.req("post", url, {req: JSON.stringify(body)});
   }
 
 
-  postForm(url: string|uri.URI, form) {
+  postForm(url: string|uri.URI, form: any) {
     return this.req("post", url, {req: form});
   }
 }
 
 
 export class RequestException {
-  constructor(detail) {
+  constructor(detail: any) {
 
   }
 }
diff --git a/lib/wallet/query.ts b/lib/wallet/query.ts
index 4eccb696b..c7420a3f7 100644
--- a/lib/wallet/query.ts
+++ b/lib/wallet/query.ts
@@ -24,7 +24,7 @@
 "use strict";
 
 
-export function Query(db) {
+export function Query(db: IDBDatabase) {
   return new QueryRoot(db);
 }
 
@@ -36,24 +36,27 @@ export interface QueryStream<T> {
   indexJoin<S>(storeName: string,
                indexName: string,
                keyFn: (obj: any) => any): QueryStream<[T,S]>;
-  filter(f: (any) => boolean): QueryStream<T>;
+  filter(f: (x: any) => boolean): QueryStream<T>;
   reduce<S>(f: (v: T, acc: S) => S, start?: S): Promise<S>;
-  flatMap(f: (T) => T[]): QueryStream<T>;
+  flatMap(f: (x: T) => T[]): QueryStream<T>;
 }
 
 
 /**
  * Get an unresolved promise together with its extracted resolve / reject
  * function.
- *
- * @returns {{resolve: any, reject: any, promise: Promise<T>}}
  */
 function openPromise<T>() {
-  let resolve, reject;
+  let resolve: ((value?: T | PromiseLike<T>) => void) | null = null;
+  let reject: ((reason?: any) => void) | null = null;
   const promise = new Promise<T>((res, rej) => {
     resolve = res;
     reject = rej;
   });
+  if (!(resolve && reject)) {
+    // Never happens, unless JS implementation is broken
+    throw Error();
+  }
   return {resolve, reject, promise};
 }
 
@@ -61,7 +64,7 @@ function openPromise<T>() {
 abstract class QueryStreamBase<T> implements QueryStream<T> {
   abstract subscribe(f: (isDone: boolean,
                          value: any,
-                         tx: IDBTransaction) => void);
+                         tx: IDBTransaction) => void): void;
 
   root: QueryRoot;
 
@@ -69,30 +72,28 @@ abstract class QueryStreamBase<T> implements QueryStream<T> {
     this.root = root;
   }
 
-  flatMap(f: (T) => T[]): QueryStream<T> {
+  flatMap(f: (x: T) => T[]): QueryStream<T> {
     return new QueryStreamFlatMap(this, f);
   }
 
   indexJoin<S>(storeName: string,
                indexName: string,
                key: any): QueryStream<[T,S]> {
-    this.root.addWork(null, storeName, false);
+    this.root.addStoreAccess(storeName, false);
     return new QueryStreamIndexJoin(this, storeName, indexName, key);
   }
 
-  filter(f: (any) => boolean): QueryStream<T> {
+  filter(f: (x: any) => boolean): QueryStream<T> {
     return new QueryStreamFilter(this, f);
   }
 
-  reduce(f, acc?): Promise<any> {
-    let leakedResolve;
-    let p = new Promise((resolve, reject) => {
-      leakedResolve = resolve;
-    });
+  reduce<A>(f: (x: any, acc?: A) => A, init?: A): Promise<any> {
+    let {resolve, promise} = openPromise();
+    let acc = init;
 
     this.subscribe((isDone, value) => {
       if (isDone) {
-        leakedResolve(acc);
+        resolve(acc);
         return;
       }
       acc = f(value, acc);
@@ -100,22 +101,28 @@ abstract class QueryStreamBase<T> implements QueryStream<T> {
 
     return Promise.resolve()
                   .then(() => this.root.finish())
-                  .then(() => p);
+                  .then(() => promise);
   }
 }
 
+type FilterFn = (e: any) => boolean;
+type SubscribeFn = (done: boolean, value: any, tx: IDBTransaction) => void;
+
+interface FlatMapFn<T> {
+  (v: T): T[];
+}
 
 class QueryStreamFilter<T> extends QueryStreamBase<T> {
   s: QueryStreamBase<T>;
-  filterFn;
+  filterFn: FilterFn;
 
-  constructor(s: QueryStreamBase<T>, filterFn) {
+  constructor(s: QueryStreamBase<T>, filterFn: FilterFn) {
     super(s.root);
     this.s = s;
     this.filterFn = filterFn;
   }
 
-  subscribe(f) {
+  subscribe(f: SubscribeFn) {
     this.s.subscribe((isDone, value, tx) => {
       if (isDone) {
         f(true, undefined, tx);
@@ -131,15 +138,15 @@ class QueryStreamFilter<T> extends QueryStreamBase<T> {
 
 class QueryStreamFlatMap<T> extends QueryStreamBase<T> {
   s: QueryStreamBase<T>;
-  flatMapFn;
+  flatMapFn: (v: T) => T[];
 
-  constructor(s: QueryStreamBase<T>, flatMapFn) {
+  constructor(s: QueryStreamBase<T>, flatMapFn: (v: T) => T[]) {
     super(s.root);
     this.s = s;
-    this.flatMap = flatMapFn;
+    this.flatMapFn = flatMapFn;
   }
 
-  subscribe(f) {
+  subscribe(f: SubscribeFn) {
     this.s.subscribe((isDone, value, tx) => {
       if (isDone) {
         f(true, undefined, tx);
@@ -154,13 +161,13 @@ class QueryStreamFlatMap<T> extends QueryStreamBase<T> {
 }
 
 
-class QueryStreamIndexJoin<T> extends QueryStreamBase<T> {
+class QueryStreamIndexJoin<T,S> extends QueryStreamBase<[T, S]> {
   s: QueryStreamBase<T>;
-  storeName;
-  key;
-  indexName;
+  storeName: string;
+  key: any;
+  indexName: string;
 
-  constructor(s, storeName: string, indexName: string, key: any) {
+  constructor(s: QueryStreamBase<T>, storeName: string, indexName: string, key: any) {
     super(s.root);
     this.s = s;
     this.storeName = storeName;
@@ -168,7 +175,7 @@ class QueryStreamIndexJoin<T> extends QueryStreamBase<T> {
     this.indexName = indexName;
   }
 
-  subscribe(f) {
+  subscribe(f: SubscribeFn) {
     this.s.subscribe((isDone, value, tx) => {
       if (isDone) {
         f(true, undefined, tx);
@@ -192,31 +199,31 @@ class QueryStreamIndexJoin<T> extends QueryStreamBase<T> {
 
 
 class IterQueryStream<T> extends QueryStreamBase<T> {
-  private storeName;
-  private options;
-  private subscribers;
+  private storeName: string;
+  private options: any;
+  private subscribers: SubscribeFn[];
 
-  constructor(qr, storeName, options) {
+  constructor(qr: QueryRoot, storeName: string, options: any) {
     super(qr);
     this.options = options;
     this.storeName = storeName;
     this.subscribers = [];
 
-    let doIt = (tx) => {
+    let doIt = (tx: IDBTransaction) => {
       const {indexName = void 0, only = void 0} = this.options;
-      let s;
+      let s: any;
       if (indexName !== void 0) {
         s = tx.objectStore(this.storeName)
               .index(this.options.indexName);
       } else {
         s = tx.objectStore(this.storeName);
       }
-      let kr = undefined;
-      if (only !== void 0) {
+      let kr: IDBKeyRange|undefined = undefined;
+      if (only !== undefined) {
         kr = IDBKeyRange.only(this.options.only);
       }
       let req = s.openCursor(kr);
-      req.onsuccess = (e) => {
+      req.onsuccess = () => {
         let cursor: IDBCursorWithValue = req.result;
         if (cursor) {
           for (let f of this.subscribers) {
@@ -231,32 +238,33 @@ class IterQueryStream<T> extends QueryStreamBase<T> {
       }
     };
 
-    this.root.addWork(doIt, null, false);
+    this.root.addWork(doIt);
   }
 
-  subscribe(f) {
+  subscribe(f: SubscribeFn) {
     this.subscribers.push(f);
   }
 }
 
 
 class QueryRoot {
-  private work = [];
+  private work: ((t: IDBTransaction) => void)[] = [];
   private db: IDBDatabase;
   private stores = new Set();
-  private kickoffPromise;
+  private kickoffPromise: Promise<void>;
 
   /**
    * Some operations is a write operation,
    * and we need to do a "readwrite" transaction/
    */
-  private hasWrite;
+  private hasWrite: boolean;
 
-  constructor(db) {
+  constructor(db: IDBDatabase) {
     this.db = db;
   }
 
-  iter<T>(storeName, {only = void 0, indexName = void 0} = {}): QueryStream<T> {
+  iter<T>(storeName: string,
+    {only = <string|undefined>undefined, indexName = <string|undefined>undefined} = {}): QueryStream<T> {
     this.stores.add(storeName);
     return new IterQueryStream(this, storeName, {only, indexName});
   }
@@ -266,7 +274,7 @@ class QueryRoot {
    * Overrides if an existing object with the same key exists
    * in the store.
    */
-  put(storeName, val): QueryRoot {
+  put(storeName: string, val: any): QueryRoot {
     let doPut = (tx: IDBTransaction) => {
       tx.objectStore(storeName).put(val);
     };
@@ -280,7 +288,7 @@ class QueryRoot {
    * Fails if the object's key is already present
    * in the object store.
    */
-  putAll(storeName, iterable): QueryRoot {
+  putAll(storeName: string, iterable: any[]): QueryRoot {
     const doPutAll = (tx: IDBTransaction) => {
       for (const obj of iterable) {
         tx.objectStore(storeName).put(obj);
@@ -295,7 +303,7 @@ class QueryRoot {
    * Fails if the object's key is already present
    * in the object store.
    */
-  add(storeName, val): QueryRoot {
+  add(storeName: string, val: any): QueryRoot {
     const doAdd = (tx: IDBTransaction) => {
       tx.objectStore(storeName).add(val);
     };
@@ -306,16 +314,16 @@ class QueryRoot {
   /**
    * Get one object from a store by its key.
    */
-  get(storeName, key): Promise<any> {
+  get(storeName: any, key: any): Promise<any> {
     if (key === void 0) {
       throw Error("key must not be undefined");
     }
 
     const {resolve, promise} = openPromise();
 
-    const doGet = (tx) => {
+    const doGet = (tx: IDBTransaction) => {
       const req = tx.objectStore(storeName).get(key);
-      req.onsuccess = (r) => {
+      req.onsuccess = () => {
         resolve(req.result);
       };
     };
@@ -329,16 +337,16 @@ class QueryRoot {
   /**
    * Get one object from a store by its key.
    */
-  getIndexed(storeName, indexName, key): Promise<any> {
+  getIndexed(storeName: string, indexName: string, key: any): Promise<any> {
     if (key === void 0) {
       throw Error("key must not be undefined");
     }
 
     const {resolve, promise} = openPromise();
 
-    const doGetIndexed = (tx) => {
+    const doGetIndexed = (tx: IDBTransaction) => {
       const req = tx.objectStore(storeName).index(indexName).get(key);
-      req.onsuccess = (r) => {
+      req.onsuccess = () => {
         resolve(req.result);
       };
     };
@@ -356,7 +364,7 @@ class QueryRoot {
     if (this.kickoffPromise) {
       return this.kickoffPromise;
     }
-    this.kickoffPromise = new Promise((resolve, reject) => {
+    this.kickoffPromise = new Promise<void>((resolve, reject) => {
       if (this.work.length == 0) {
         resolve();
         return;
@@ -376,8 +384,8 @@ class QueryRoot {
   /**
    * Delete an object by from the given object store.
    */
-  delete(storeName: string, key): QueryRoot {
-    const doDelete = (tx) => {
+  delete(storeName: string, key: any): QueryRoot {
+    const doDelete = (tx: IDBTransaction) => {
       tx.objectStore(storeName).delete(key);
     };
     this.addWork(doDelete, storeName, true);
@@ -387,17 +395,21 @@ class QueryRoot {
   /**
    * Low-level function to add a task to the internal work queue.
    */
-  addWork(workFn: (IDBTransaction) => void,
-          storeName: string,
-          isWrite: boolean) {
+  addWork(workFn: (t: IDBTransaction) => void,
+          storeName?: string,
+          isWrite?: boolean) {
+    this.work.push(workFn);
+    if (storeName) {
+      this.addStoreAccess(storeName, isWrite);
+    }
+  }
+
+  addStoreAccess(storeName: string, isWrite?: boolean) {
     if (storeName) {
       this.stores.add(storeName);
     }
     if (isWrite) {
       this.hasWrite = true;
     }
-    if (workFn) {
-      this.work.push(workFn);
-    }
   }
 }
\ No newline at end of file
diff --git a/lib/wallet/types.ts b/lib/wallet/types.ts
index 2434dca32..e8b7a1e39 100644
--- a/lib/wallet/types.ts
+++ b/lib/wallet/types.ts
@@ -392,5 +392,5 @@ export interface CheckRepurchaseResult {
 
 
 export interface Notifier {
-  notify();
+  notify(): void;
 }
diff --git a/lib/wallet/wallet.ts b/lib/wallet/wallet.ts
index 9edad2c5c..367c9cbcd 100644
--- a/lib/wallet/wallet.ts
+++ b/lib/wallet/wallet.ts
@@ -154,12 +154,12 @@ interface Transaction {
 export interface Badge {
   setText(s: string): void;
   setColor(c: string): void;
-  startBusy();
-  stopBusy();
+  startBusy(): void;
+  stopBusy(): void;
 }
 
 
-function deepEquals(x, y) {
+function deepEquals(x: any, y: any): boolean {
   if (x === y) {
     return true;
   }
@@ -179,7 +179,7 @@ function flatMap<T, U>(xs: T[], f: (x: T) => U[]): U[] {
 }
 
 
-function getTalerStampSec(stamp: string): number {
+function getTalerStampSec(stamp: string): number|null {
   const m = stamp.match(/\/?Date\(([0-9]*)\)\/?/);
   if (!m) {
     return null;
@@ -188,7 +188,7 @@ function getTalerStampSec(stamp: string): number {
 }
 
 
-function setTimeout(f, t) {
+function setTimeout(f: any, t: number) {
   return chrome.extension.getBackgroundPage().setTimeout(f, t);
 }
 
@@ -211,13 +211,13 @@ interface HttpRequestLibrary {
 
   get(url: string|uri.URI): Promise<HttpResponse>;
 
-  postJson(url: string|uri.URI, body): Promise<HttpResponse>;
+  postJson(url: string|uri.URI, body: any): Promise<HttpResponse>;
 
-  postForm(url: string|uri.URI, form): Promise<HttpResponse>;
+  postForm(url: string|uri.URI, form: any): Promise<HttpResponse>;
 }
 
 
-function copy(o) {
+function copy(o: any) {
   return JSON.parse(JSON.stringify(o));
 }
 
@@ -240,11 +240,18 @@ interface KeyUpdateInfo {
 function getWithdrawDenomList(amountAvailable: AmountJson,
                               denoms: Denomination[]): Denomination[] {
   let remaining = Amounts.copy(amountAvailable);
-  let ds: Denomination[] = [];
+  const ds: Denomination[] = [];
+
+  console.log("available denoms");
+  console.log(denoms);
 
   denoms = denoms.filter(isWithdrawableDenom);
   denoms.sort((d1, d2) => Amounts.cmp(d2.value, d1.value));
 
+  console.log("withdrawable denoms");
+  console.log(denoms);
+
+
   // This is an arbitrary number of coins
   // we can withdraw in one go.  It's not clear if this limit
   // is useful ...
@@ -355,7 +362,7 @@ export class Wallet {
 
     let x: number;
 
-    function storeExchangeCoin(mc, url) {
+    function storeExchangeCoin(mc: any, url: string) {
       let exchange: IExchangeInfo = mc[0];
       console.log("got coin for exchange", url);
       let coin: Coin = mc[1];
@@ -366,18 +373,16 @@ export class Wallet {
                     exchange.baseUrl);
         return;
       }
-      let cd = {
-        coin: coin,
-        denom: exchange.active_denoms.find((e) => e.denom_pub === coin.denomPub)
-      };
-      if (!cd.denom) {
+      let denom = exchange.active_denoms.find((e) => e.denom_pub === coin.denomPub);
+      if (!denom) {
         console.warn("denom not found (database inconsistent)");
         return;
       }
-      if (cd.denom.value.currency !== paymentAmount.currency) {
+      if (denom.value.currency !== paymentAmount.currency) {
         console.warn("same pubkey for different currencies");
         return;
       }
+      let cd = {coin, denom};
       let x = m[url];
       if (!x) {
         m[url] = [cd];
@@ -464,7 +469,7 @@ export class Wallet {
   private recordConfirmPay(offer: Offer,
                            payCoinInfo: PayCoinInfo,
                            chosenExchange: string): Promise<void> {
-    let payReq = {};
+    let payReq: any = {};
     payReq["amount"] = offer.contract.amount;
     payReq["coins"] = payCoinInfo.map((x) => x.sig);
     payReq["H_contract"] = offer.H_contract;
@@ -581,7 +586,7 @@ export class Wallet {
    * Retrieve all necessary information for looking up the contract
    * with the given hash.
    */
-  executePayment(H_contract): Promise<any> {
+  executePayment(H_contract: string): Promise<any> {
     return Promise.resolve().then(() => {
       return Query(this.db)
         .get("transactions", H_contract)
@@ -607,7 +612,7 @@ export class Wallet {
    * First fetch information requred to withdraw from the reserve,
    * then deplete the reserve, withdrawing coins until it is empty.
    */
-  private processReserve(reserveRecord): void {
+  private processReserve(reserveRecord: any): void {
     let retryDelayMs = 100;
     const opId = "reserve-" + reserveRecord.reserve_pub;
     this.startOperation(opId);
@@ -637,7 +642,7 @@ export class Wallet {
   }
 
 
-  private processPreCoin(preCoin, retryDelayMs = 100): void {
+  private processPreCoin(preCoin: any, retryDelayMs = 100): void {
     this.withdrawExecute(preCoin)
         .then((c) => this.storeCoin(c))
         .catch((e) => {
@@ -803,7 +808,7 @@ export class Wallet {
   /**
    * Withdraw coins from a reserve until it is empty.
    */
-  private depleteReserve(reserve, exchange: IExchangeInfo): Promise<void> {
+  private depleteReserve(reserve: any, exchange: IExchangeInfo): Promise<void> {
     let denomsAvailable: Denomination[] = copy(exchange.active_denoms);
     let denomsForWithdraw = getWithdrawDenomList(reserve.current_amount,
                                                  denomsAvailable);
@@ -912,7 +917,7 @@ export class Wallet {
    * Optionally link the reserve entry to the new or existing
    * exchange entry in then DB.
    */
-  updateExchangeFromUrl(baseUrl): Promise<IExchangeInfo> {
+  updateExchangeFromUrl(baseUrl: string): Promise<IExchangeInfo> {
     baseUrl = canonicalizeBaseUrl(baseUrl);
     let reqUrl = URI("keys").absoluteTo(baseUrl);
     return this.http.get(reqUrl).then((resp) => {
@@ -927,8 +932,8 @@ export class Wallet {
 
   private updateExchangeFromJson(baseUrl: string,
                                  exchangeKeysJson: KeysJson): Promise<IExchangeInfo> {
-    let updateTimeSec = getTalerStampSec(exchangeKeysJson.list_issue_date);
-    if (!updateTimeSec) {
+    const updateTimeSec = getTalerStampSec(exchangeKeysJson.list_issue_date);
+    if (updateTimeSec === null) {
       throw Error("invalid update time");
     }
 
@@ -947,7 +952,7 @@ export class Wallet {
         console.log("making fresh exchange");
       } else {
         if (updateTimeSec < r.last_update_time) {
-          console.log("outdated /keys, not updating")
+          console.log("outdated /keys, not updating");
           return Promise.resolve(r);
         }
         exchangeInfo = r;
@@ -966,9 +971,9 @@ export class Wallet {
                            {indexName: "exchangeBaseUrl", only: baseUrl})
                      .reduce((coin: Coin, suspendedCoins: Coin[]) => {
                        if (!updatedExchangeInfo.active_denoms.find((c) => c.denom_pub == coin.denomPub)) {
-                         return [].concat(suspendedCoins, [coin]);
+                         return Array.prototype.concat(suspendedCoins, [coin]);
                        }
-                       return [].concat(suspendedCoins);
+                       return Array.prototype.concat(suspendedCoins);
                      }, [])
                      .then((suspendedCoins: Coin[]) => {
                        let q = Query(this.db);
@@ -999,8 +1004,8 @@ export class Wallet {
       let found = false;
       for (let oldDenom of exchangeInfo.all_denoms) {
         if (oldDenom.denom_pub === newDenom.denom_pub) {
-          let a = Object.assign({}, oldDenom);
-          let b = Object.assign({}, newDenom);
+          let a: any = Object.assign({}, oldDenom);
+          let b: any = Object.assign({}, newDenom);
           // pub hash is only there for convenience in the wallet
           delete a["pub_hash"];
           delete b["pub_hash"];
@@ -1048,7 +1053,7 @@ export class Wallet {
    * that is currenctly available for spending in the wallet.
    */
   getBalances(): Promise<any> {
-    function collectBalances(c: Coin, byCurrency) {
+    function collectBalances(c: Coin, byCurrency: any) {
       if (c.suspended) {
         return byCurrency;
       }
@@ -1074,7 +1079,7 @@ export class Wallet {
    * Retrive the full event history for this wallet.
    */
   getHistory(): Promise<any> {
-    function collect(x, acc) {
+    function collect(x: any, acc: any) {
       acc.push(x);
       return acc;
     }
@@ -1099,7 +1104,7 @@ export class Wallet {
                   [contract.merchant_pub, contract.repurchase_correlation_id])
       .then((result: Transaction) => {
         console.log("db result", result);
-        let isRepurchase;
+        let isRepurchase: boolean;
         if (result) {
           console.assert(result.contract.repurchase_correlation_id == contract.repurchase_correlation_id);
           return {
diff --git a/lib/wallet/wxMessaging.ts b/lib/wallet/wxMessaging.ts
index a8dc27524..9c08b20ca 100644
--- a/lib/wallet/wxMessaging.ts
+++ b/lib/wallet/wxMessaging.ts
@@ -15,7 +15,13 @@
  */
 
 
-import {Wallet, Offer, Badge, ConfirmReserveRequest, CreateReserveRequest} from "./wallet";
+import {
+  Wallet,
+  Offer,
+  Badge,
+  ConfirmReserveRequest,
+  CreateReserveRequest
+} from "./wallet";
 import {deleteDb, exportDb, openTalerDb} from "./db";
 import {BrowserHttpLib} from "./http";
 import {Checkable} from "./checkable";
@@ -48,11 +54,17 @@ function makeHandlers(db: IDBDatabase,
       return exportDb(db);
     },
     ["ping"]: function(detail, sender) {
-      return Promise.resolve({});
+      if (!sender || !sender.tab || !sender.tab.id) {
+        return Promise.resolve();
+      }
+      let id: number = sender.tab.id;
+      let info: any = <any>paymentRequestCookies[id];
+      delete paymentRequestCookies[id];
+      return Promise.resolve(info);
     },
     ["reset"]: function(detail, sender) {
       if (db) {
-        let tx = db.transaction(db.objectStoreNames, 'readwrite');
+        let tx = db.transaction(Array.from(db.objectStoreNames), 'readwrite');
         for (let i = 0; i < db.objectStoreNames.length; i++) {
           tx.objectStore(db.objectStoreNames[i]).clear();
         }
@@ -81,7 +93,7 @@ function makeHandlers(db: IDBDatabase,
       return wallet.confirmReserve(req);
     },
     ["confirm-pay"]: function(detail, sender) {
-      let offer;
+      let offer: Offer;
       try {
         offer = Offer.checked(detail.offer);
       } catch (e) {
@@ -100,7 +112,7 @@ function makeHandlers(db: IDBDatabase,
       return wallet.confirmPay(offer);
     },
     ["check-pay"]: function(detail, sender) {
-      let offer;
+      let offer: Offer;
       try {
         offer = Offer.checked(detail.offer);
       } catch (e) {
@@ -173,14 +185,14 @@ class ChromeBadge implements Badge {
 }
 
 
-function dispatch(handlers, req, sender, sendResponse) {
+function dispatch(handlers: any, req: any, sender: any, sendResponse: any) {
   if (req.type in handlers) {
     Promise
       .resolve()
       .then(() => {
         const p = handlers[req.type](req.detail, sender);
 
-        return p.then((r) => {
+        return p.then((r: any) => {
           sendResponse(r);
         })
       })
@@ -231,12 +243,58 @@ class ChromeNotifier implements Notifier {
 }
 
 
+/**
+ * Mapping from tab ID to payment information (if any).
+ */
+let paymentRequestCookies: {[n: number]: any} = {};
+
+function handleHttpPayment(headerList: chrome.webRequest.HttpHeader[],
+                           url: string, tabId: number): any {
+  const headers: {[s: string]: string} = {};
+  for (let kv of headerList) {
+    if (kv.value) {
+      headers[kv.name.toLowerCase()] = kv.value;
+    }
+  }
+
+  const contractUrl = headers["x-taler-contract-url"];
+  if (contractUrl !== undefined) {
+    paymentRequestCookies[tabId] = {type: "fetch", contractUrl};
+    return;
+  }
+
+  const contractHash = headers["x-taler-contract-hash"];
+
+  if (contractHash !== undefined) {
+    const payUrl = headers["x-taler-pay-url"];
+    if (payUrl === undefined) {
+      console.log("malformed 402, X-Taler-Pay-Url missing");
+      return;
+    }
+
+    // Offer URL is optional
+    const offerUrl = headers["x-taler-offer-url"];
+    paymentRequestCookies[tabId] = {
+      type: "execute",
+      offerUrl,
+      payUrl,
+      contractHash
+    };
+    return;
+  }
+
+  // looks like it's not a taler request, it might be
+  // for a different payment system (or the shop is buggy)
+  console.log("ignoring non-taler 402 response");
+}
+
+
 export function wxMain() {
   chrome.browserAction.setBadgeText({text: ""});
 
   chrome.tabs.query({}, function(tabs) {
     for (let tab of tabs) {
-      if (!tab.url) {
+      if (!tab.url || !tab.id) {
         return;
       }
       let uri = URI(tab.url);
@@ -255,11 +313,14 @@ export function wxMain() {
            console.error("could not open database");
            console.error(e);
          })
-         .then((db) => {
+         .then((db: IDBDatabase) => {
            let http = new BrowserHttpLib();
            let badge = new ChromeBadge();
            let notifier = new ChromeNotifier();
            let wallet = new Wallet(db, http, badge, notifier);
+
+           // Handlers for messages coming directly from the content
+           // script on the page
            let handlers = makeHandlers(db, wallet);
            chrome.runtime.onMessage.addListener((req, sender, sendResponse) => {
              try {
@@ -276,6 +337,19 @@ export function wxMain() {
                return false;
              }
            });
+
+           // Handlers for catching HTTP requests
+           chrome.webRequest.onHeadersReceived.addListener((details) => {
+             if (details.statusCode != 402) {
+               return;
+             }
+             console.log(`got 402 from ${details.url}`);
+             return handleHttpPayment(details.responseHeaders || [],
+                                      details.url,
+                                      details.tabId);
+           }, {urls: ["<all_urls>"]}, ["responseHeaders", "blocking"]);
+
+
          })
          .catch((e) => {
            console.error("could not initialize wallet messaging");