commit 47b1bdaefb0e3e5dc1e5b3a3f7f813f86f02167b
parent e00d7b3ebdc01920253ab40e2be109cbefaeb6ff
Author: Marcello Stanisci <marcello.stanisci@inria.fr>
Date: Tue, 28 Mar 2017 21:21:06 +0200
finishing explanation of X-Taler-Contract-Query
Diffstat:
2 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/php/doc/tutorial.texi b/php/doc/tutorial.texi
@@ -254,8 +254,8 @@ browser.
@section A helper function to generate the order
-We make distinction between *three* different stages of the
-document that describes the purchase being served.
+We make distinction between @emph{three} different stages of what it
+informally called "contract".
In a very first stage, we call it the @emph{order}: that occurs when
the frontend generates the first JSON that misses some information
@@ -373,6 +373,8 @@ the wallet will pick those coins it spent on that fulfillment
page and resend them (therefore @emph{replaying} the payment).
In other words, new coins are used only on unknown fulfillment
pages.
+This header is supposed to be removed in future versions of the
+wallet though, as it only works with the value @code{"fulfillment_url"}.
@item X-Taler-Offer-Url
@cindex X-Taler-Offer-Url
In case that the wallet does not know about this payment already,
diff --git a/python/doc/tutorial.texi b/python/doc/tutorial.texi
@@ -366,6 +366,16 @@ def fulfillment():
@end smallexample
@c FIXME: check with Florian: isn't 'x-taler-contract-query' dead by now?
+The @code{X-Taler-Contract-Query} header is crucial for implementing replayable
+payments. In fact, upon receiving such a header, the wallet will look in its
+internal database if a payment to the current fulfillment URL has already been
+sent. If that's the case, then the coins from that previous payment will be
+sent to the @emph{pay_url}.
+That is exactly what happens when the user visits some bookmarked fulfillment
+page in order to see again what they already paid for.
+That header is scheduled to be removed in future versions of the wallet,
+as it only works with the value @code{"fulfillment_url"}.
+
@section Receiving payments via Taler
The final next step for the frontend is to receive the payment from the
