/*
This file is part of TALER
Copyright (C) 2014-2018, 2020 Taler Systems SA
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2.1, or (at your option) any later version.
TALER is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with
TALER; see the file COPYING.LGPL. If not, see
*/
/**
* @file lib/merchant_api_get_config.c
* @brief Implementation of the /config request of the merchant's HTTP API
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include /* just for HTTP status codes */
#include
#include
#include "taler_merchant_service.h"
#include
#include
/**
* Which version of the Taler protocol is implemented
* by this library? Used to determine compatibility.
*/
#define MERCHANT_PROTOCOL_CURRENT 1
/**
* How many configs are we backwards compatible with?
*/
#define MERCHANT_PROTOCOL_AGE 0
/**
* @brief A handle for /config operations
*/
struct TALER_MERCHANT_ConfigGetHandle
{
/**
* The url for this request.
*/
char *url;
/**
* Handle for the request.
*/
struct GNUNET_CURL_Job *job;
/**
* Function to call with the result.
*/
TALER_MERCHANT_ConfigCallback cb;
/**
* Closure for @a cb.
*/
void *cb_cls;
/**
* Reference to the execution context.
*/
struct GNUNET_CURL_Context *ctx;
};
/**
* Function called when we're done processing the
* HTTP /config request.
*
* @param cls the `struct TALER_MERCHANT_ConfigGetHandle`
* @param response_code HTTP response code, 0 on error
* @param json response body, NULL if not in JSON
*/
static void
handle_config_finished (void *cls,
long response_code,
const void *response)
{
struct TALER_MERCHANT_ConfigGetHandle *vgh = cls;
const json_t *json = response;
struct TALER_MERCHANT_HttpResponse hr = {
.http_status = (unsigned int) response_code,
.reply = json
};
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Got /config response with status code %u\n",
(unsigned int) response_code);
vgh->job = NULL;
switch (response_code)
{
case MHD_HTTP_OK:
{
struct TALER_MERCHANT_ConfigInformation vi;
enum TALER_MERCHANT_VersionCompatibility vc =
TALER_MERCHANT_VC_PROTOCOL_ERROR;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_string ("currency",
&vi.currency),
GNUNET_JSON_spec_string ("version",
&vi.version),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (json,
spec,
NULL, NULL))
{
hr.http_status = 0;
hr.ec = TALER_EC_INVALID_RESPONSE;
}
else
{
unsigned int age;
unsigned int revision;
unsigned int current;
if (3 != sscanf (vi.version,
"%u:%u:%u",
¤t,
&revision,
&age))
{
hr.http_status = 0;
hr.ec = TALER_EC_INVALID_RESPONSE;
}
else
{
vc = TALER_MERCHANT_VC_MATCH;
if (MERCHANT_PROTOCOL_CURRENT < current)
{
vc |= TALER_MERCHANT_VC_NEWER;
if (MERCHANT_PROTOCOL_CURRENT < current - age)
vc |= TALER_MERCHANT_VC_INCOMPATIBLE;
}
if (MERCHANT_PROTOCOL_CURRENT > current)
{
vc |= TALER_MERCHANT_VC_OLDER;
if (MERCHANT_PROTOCOL_CURRENT - MERCHANT_PROTOCOL_AGE > current)
vc |= TALER_MERCHANT_VC_INCOMPATIBLE;
}
}
}
vgh->cb (vgh->cb_cls,
&hr,
&vi,
vc);
TALER_MERCHANT_config_get_cancel (vgh);
return;
}
default:
/* unexpected response code */
hr.ec = TALER_JSON_get_error_code (json);
hr.hint = TALER_JSON_get_error_hint (json);
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Unexpected response code %u/%d\n",
(unsigned int) response_code,
(int) hr.ec);
vgh->cb (vgh->cb_cls,
&hr,
NULL,
TALER_MERCHANT_VC_PROTOCOL_ERROR);
break;
}
TALER_MERCHANT_config_get_cancel (vgh);
}
/**
* Get the config data of a merchant. Will connect to the merchant backend
* and obtain information about the backend. The respective information will
* be passed to the @a config_cb once available.
*
* @param ctx the context
* @param backend_url HTTP base URL for the backend
* @param config_cb function to call with the
* backend's config information
* @param config_cb_cls closure for @a config_cb
* @return the config check handle; NULL upon error
*/
struct TALER_MERCHANT_ConfigGetHandle *
TALER_MERCHANT_config_get (struct GNUNET_CURL_Context *ctx,
const char *backend_url,
TALER_MERCHANT_ConfigCallback config_cb,
void *config_cb_cls)
{
struct TALER_MERCHANT_ConfigGetHandle *vgh;
CURL *eh;
vgh = GNUNET_new (struct TALER_MERCHANT_ConfigGetHandle);
vgh->ctx = ctx;
vgh->cb = config_cb;
vgh->cb_cls = config_cb_cls;
vgh->url = TALER_url_join (backend_url,
"config",
NULL);
if (NULL == vgh->url)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Could not construct request URL.\n");
GNUNET_free (vgh);
return NULL;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Requesting URL '%s'\n",
vgh->url);
eh = curl_easy_init ();
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_URL,
vgh->url));
vgh->job = GNUNET_CURL_job_add (ctx,
eh,
&handle_config_finished,
vgh);
return vgh;
}
/**
* Cancel /config request. Must not be called by clients after
* the callback was invoked.
*
* @param vgh request to cancel.
*/
void
TALER_MERCHANT_config_get_cancel (struct TALER_MERCHANT_ConfigGetHandle *vgh)
{
if (NULL != vgh->job)
{
GNUNET_CURL_job_cancel (vgh->job);
vgh->job = NULL;
}
GNUNET_free (vgh->url);
GNUNET_free (vgh);
}
/* end of merchant_api_config_get.c */