implementation of GET /private/tips

1 files changed, 369 insertions, 0 deletions

diff --git a/src/lib/merchant_api_get_tips.c b/src/lib/merchant_api_get_tips.c
index 05f8e7b4..63bcb940 100644
--- a/src/lib/merchant_api_get_tips.c
+++ b/src/lib/merchant_api_get_tips.c
@@ -19,3 +19,372 @@
  * @brief Implementation of the GET /private/tips request of the merchant's HTTP API
  * @author Jonathan Buchanan
  */
+#include "platform.h"
+#include <curl/curl.h>
+#include <jansson.h>
+#include <microhttpd.h> /* just for HTTP status codes */
+#include <gnunet/gnunet_util_lib.h>
+#include <gnunet/gnunet_curl_lib.h>
+#include "taler_merchant_service.h"
+#include <taler/taler_json_lib.h>
+#include <taler/taler_signatures.h>
+
+
+/**
+ * Handle for a GET /private/tips operation.
+ */
+struct TALER_MERCHANT_TipsGetHandle
+{
+  /**
+   * The url for this request.
+   */
+  char *url;
+
+  /**
+   * Handle for the request.
+   */
+  struct GNUNET_CURL_Job *job;
+
+  /**
+   * Function to call with the result.
+   */
+  TALER_MERCHANT_TipsGetCallback cb;
+
+  /**
+   * Closure for @a cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Reference to the execution context.
+   */
+  struct GNUNET_CURL_Context *ctx;
+
+};
+
+
+/**
+ * Parse tip information from @a ia.
+ *
+ * @param ia JSON array (or NULL!) tip order data
+ * @param tgh operation handle
+ * @return #GNUNET_OK on success
+ */
+static int
+parse_tips (const json_t *ia,
+            struct TALER_MERCHANT_TipsGetHandle *tgh)
+{
+  unsigned int tes_len = json_array_size (ia);
+  struct TALER_MERCHANT_TipEntry tes[tes_len];
+  size_t index;
+  json_t *value;
+  int ret;
+
+  ret = GNUNET_OK;
+  json_array_foreach (ia, index, value) {
+    struct TALER_MERCHANT_TipEntry *ie = &tes[index];
+    struct GNUNET_JSON_Specification spec[] = {
+      GNUNET_JSON_spec_uint64 ("row_id",
+                               &ie->row_id),
+      GNUNET_JSON_spec_fixed_auto ("tip_id",
+                                   &ie->tip_id),
+      TALER_JSON_spec_amount ("tip_amount",
+                              &ie->tip_amount),
+      GNUNET_JSON_spec_end ()
+    };
+
+    if (GNUNET_OK !=
+        GNUNET_JSON_parse (value,
+                           spec,
+                           NULL, NULL))
+    {
+      GNUNET_break_op (0);
+      ret = GNUNET_SYSERR;
+      continue;
+    }
+    if (GNUNET_SYSERR == ret)
+      break;
+  }
+  if (GNUNET_OK == ret)
+  {
+    struct TALER_MERCHANT_HttpResponse hr = {
+      .http_status = MHD_HTTP_OK
+    };
+
+    tgh->cb (tgh->cb_cls,
+             &hr,
+             tes_len,
+             tes);
+    tgh->cb = NULL; /* just to be sure */
+  }
+  return ret;
+}
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP GET /private/tips request.
+ *
+ * @param cls the `struct TALER_MERCHANT_TipsGetHandle`
+ * @param response_code HTTP response code, 0 on error
+ * @param json response body, NULL if not in JSON
+ */
+static void
+handle_get_tips_finished (void *cls,
+                          long response_code,
+                          const void *response)
+{
+  struct TALER_MERCHANT_TipsGetHandle *tgh = cls;
+  const json_t *json = response;
+  struct TALER_MERCHANT_HttpResponse hr = {
+    .http_status = (unsigned int) response_code,
+    .reply = json
+  };
+
+  tgh->job = NULL;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Got /private/tips response with status code %u\n",
+              (unsigned int) response_code);
+  switch (response_code)
+  {
+  case MHD_HTTP_OK:
+    {
+      json_t *tips;
+      struct GNUNET_JSON_Specification spec[] = {
+        GNUNET_JSON_spec_json ("tips",
+                               &tips),
+        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
+      {
+        if ( (! json_is_array (tips)) ||
+             (GNUNET_OK ==
+              parse_tips (tips,
+                          tgh)) )
+        {
+          GNUNET_JSON_parse_free (spec);
+          TALER_MERCHANT_tips_get_cancel (tgh);
+          return;
+        }
+        else
+        {
+          hr.http_status = 0;
+          hr.ec = TALER_EC_INVALID_RESPONSE;
+        }
+      }
+      GNUNET_JSON_parse_free (spec);
+      break;
+    }
+  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);
+    break;
+  }
+  tgh->cb (tgh->cb_cls,
+           &hr,
+           0,
+           NULL);
+  TALER_MERCHANT_tips_get_cancel (tgh);
+}
+
+
+/**
+ * Make a GET /private/tips request.
+ *
+ * @param ctx the context
+ * @param backend_url HTTP base URL for the backend
+ * @param cb function to call with the backend's tip information
+ * @param cb_cls closure for @a cb
+ * @return the request handle; NULL upon error
+ */
+struct TALER_MERCHANT_TipsGetHandle *
+TALER_MERCHANT_tips_get (
+  struct GNUNET_CURL_Context *ctx,
+  const char *backend_url,
+  TALER_MERCHANT_TipsGetCallback cb,
+  void *cb_cls)
+{
+  return TALER_MERCHANT_tips_get2 (ctx,
+                                   backend_url,
+                                   false,
+                                   -20,
+                                   UINT64_MAX,
+                                   cb,
+                                   cb_cls);
+}
+
+
+/**
+ * Issue a GET /private/tips request with filters to the backend.
+ *
+ * @param ctx execution context
+ * @param backend_url base URL of the merchant backend
+ * @param include_expired whether to return all tips or only unexpired tips
+ * @param limit number of results to return, negative for descending row id, positive for ascending
+ * @param offset row id to start returning results from
+ * @param cb function to call with the result
+ * @param cb_cls closure for @a cb
+ * @return handle for this operation, NULL upon errors
+ */
+struct TALER_MERCHANT_TipsGetHandle *
+TALER_MERCHANT_tips_get2 (struct GNUNET_CURL_Context *ctx,
+                          const char *backend_url,
+                          enum TALER_MERCHANT_YesNoAll expired,
+                          int64_t limit,
+                          uint64_t offset,
+                          TALER_MERCHANT_TipsGetCallback cb,
+                          void *cb_cls)
+{
+  struct TALER_MERCHANT_TipsGetHandle *tgh;
+  CURL *eh;
+
+  GNUNET_assert (NULL != backend_url);
+  if (0 == limit)
+  {
+    GNUNET_break (0);
+    return NULL;
+  }
+  tgh = GNUNET_new (struct TALER_MERCHANT_TipsGetHandle);
+  tgh->ctx = ctx;
+  tgh->cb = cb;
+  tgh->cb_cls = cb_cls;
+
+  /* build tgh->url with the various optional arguments */
+  {
+    struct GNUNET_Buffer buf = { 0 };
+    bool first = true;
+    /**
+     * Macro to append @a a and @a b to @a buf, using
+     * the right separators between key (@a a) and
+     * value (@a b). Uses "first" to decide between
+     * using "?" and "&" as the separator.
+     *
+     * @param a a key
+     * @param b a value
+     */
+#define APPEND(a,b)                             \
+  do { \
+    if (first) \
+    GNUNET_buffer_write_str (&buf, \
+                             "?");            \
+    else \
+    GNUNET_buffer_write_str (&buf, \
+                             "&"); \
+    first = false; \
+    GNUNET_buffer_write_str (&buf, (a)); \
+    GNUNET_buffer_write_str (&buf, "="); \
+    GNUNET_buffer_write_str (&buf, (b)); \
+  } while (0)
+
+    {
+      char *url;
+
+      url = TALER_url_join (backend_url,
+                            "private/tips",
+                            NULL);
+      if (NULL == url)
+        goto finished;
+      GNUNET_buffer_write_str (&buf,
+                               url);
+      GNUNET_free (url);
+    }
+    if (TALER_MERCHANT_YNA_NO != expired)
+      APPEND ("expired",
+              (TALER_MERCHANT_YNA_YES == expired) ? "yes" : "all");
+    if (limit > 0)
+    {
+      if (0 != offset)
+      {
+        char cbuf[30];
+
+        GNUNET_snprintf (cbuf,
+                         sizeof (cbuf),
+                         "%llu",
+                         (unsigned long long) offset);
+        APPEND ("offset",
+                cbuf);
+      }
+    }
+    else
+    {
+      if (UINT64_MAX != offset)
+      {
+        char cbuf[30];
+
+        GNUNET_snprintf (cbuf,
+                         sizeof (cbuf),
+                         "%llu",
+                         (unsigned long long) offset);
+        APPEND ("offset",
+                cbuf);
+      }
+    }
+    if (-20 != limit)
+    {
+      char cbuf[30];
+
+      GNUNET_snprintf (cbuf,
+                       sizeof (cbuf),
+                       "%lld",
+                       (long long) limit);
+      APPEND ("limit",
+              cbuf);
+    }
+    tgh->url = GNUNET_buffer_reap_str (&buf);
+#undef APPEND
+  }
+
+finished:
+  if (NULL == tgh->url)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Could not construct request URL.\n");
+    GNUNET_free (tgh);
+    return NULL;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Requesting URL '%s'\n",
+              tgh->url);
+  eh = curl_easy_init ();
+  GNUNET_assert (CURLE_OK ==
+                 curl_easy_setopt (eh,
+                                   CURLOPT_URL,
+                                   tgh->url));
+  tgh->job = GNUNET_CURL_job_add (ctx,
+                                  eh,
+                                  GNUNET_YES,
+                                  &handle_get_tips_finished,
+                                  tgh);
+  return tgh;
+}
+
+
+/**
+ * Cancel GET /private/tips request.  Must not be called by clients after
+ * the callback was invoked.
+ *
+ * @param ogh request to cancel.
+ */
+void
+TALER_MERCHANT_tips_get_cancel (
+  struct TALER_MERCHANT_TipsGetHandle *tgh)
+{
+  if (NULL != tgh->job)
+    GNUNET_CURL_job_cancel (tgh->job);
+  GNUNET_free (tgh->url);
+  GNUNET_free (tgh);
+}