add spa logic

2 files changed, 369 insertions, 1 deletions

diff --git a/src/mhd/Makefile.am b/src/mhd/Makefile.am
index 703e34ca4..563ebf398 100644
--- a/src/mhd/Makefile.am
+++ b/src/mhd/Makefile.am
@@ -14,7 +14,8 @@ libtalermhd_la_SOURCES = \
   mhd_legal.c \
   mhd_parsing.c \
   mhd_responses.c \
-  mhd_run.c
+  mhd_run.c \
+  mhd_spa.c
 libtalermhd_la_LDFLAGS = \
   -version-info 3:1:3 \
   -no-undefined
diff --git a/src/mhd/mhd_spa.c b/src/mhd/mhd_spa.c
new file mode 100644
index 000000000..c4aff281d
--- /dev/null
+++ b/src/mhd/mhd_spa.c
@@ -0,0 +1,367 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2020, 2023, 2024 Taler Systems SA
+
+  TALER is free software; you can redistribute it and/or modify it under the
+  terms of the GNU General Public License as published by the Free Software
+  Foundation; either version 3, 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 EXCHANGEABILITY or FITNESS FOR
+  A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along with
+  TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file mhd_spa.c
+ * @brief logic to load single page apps
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <gnunet/gnunet_util_lib.h>
+#include "taler_util.h"
+#include "taler_mhd_lib.h"
+#include <gnunet/gnunet_mhd_compat.h>
+
+
+/**
+ * Resource from the WebUi.
+ */
+struct WebuiFile
+{
+  /**
+   * Kept in a DLL.
+   */
+  struct WebuiFile *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct WebuiFile *prev;
+
+  /**
+   * Path this resource matches.
+   */
+  char *path;
+
+  /**
+   * SPA resource, compressed.
+   */
+  struct MHD_Response *zresponse;
+
+  /**
+   * SPA resource, vanilla.
+   */
+  struct MHD_Response *response;
+
+};
+
+
+/**
+ * Resource from the WebUi.
+ */
+struct TALER_MHD_Spa
+{
+  /**
+   * Resources of the WebUI, kept in a DLL.
+   */
+  struct WebuiFile *webui_head;
+
+  /**
+   * Resources of the WebUI, kept in a DLL.
+   */
+  struct WebuiFile *webui_tail;
+};
+
+
+MHD_RESULT
+TALER_MHD_spa_handler (const struct TALER_MHD_Spa *spa,
+                       struct MHD_Connection *connection,
+                       const char *path)
+{
+  struct WebuiFile *w = NULL;
+
+  if ( (NULL == path) ||
+       (0 == strcmp (path,
+                     "")) )
+    path = "index.html";
+  for (struct WebuiFile *pos = spa->webui_head;
+       NULL != pos;
+       pos = pos->next)
+    if (0 == strcmp (path,
+                     pos->path))
+    {
+      w = pos;
+      break;
+    }
+  if (NULL == w)
+    return TALER_MHD_reply_with_error (connection,
+                                       MHD_HTTP_NOT_FOUND,
+                                       TALER_EC_GENERIC_ENDPOINT_UNKNOWN,
+                                       path);
+  if ( (MHD_YES ==
+        TALER_MHD_can_compress (connection)) &&
+       (NULL != w->zresponse) )
+    return MHD_queue_response (connection,
+                               MHD_HTTP_OK,
+                               w->zresponse);
+  return MHD_queue_response (connection,
+                             MHD_HTTP_OK,
+                             w->response);
+}
+
+
+/**
+ * Function called on each file to load for the WebUI.
+ *
+ * @param cls the `struct TALER_MHD_Spa *` to build
+ * @param dn name of the file to load
+ */
+static enum GNUNET_GenericReturnValue
+build_webui (void *cls,
+             const char *dn)
+{
+  static const struct
+  {
+    const char *ext;
+    const char *mime;
+  } mime_map[] = {
+    {
+      .ext = "css",
+      .mime = "text/css"
+    },
+    {
+      .ext = "html",
+      .mime = "text/html"
+    },
+    {
+      .ext = "js",
+      .mime = "text/javascript"
+    },
+    {
+      .ext = "jpg",
+      .mime = "image/jpeg"
+    },
+    {
+      .ext = "jpeg",
+      .mime = "image/jpeg"
+    },
+    {
+      .ext = "png",
+      .mime = "image/png"
+    },
+    {
+      .ext = "svg",
+      .mime = "image/svg+xml"
+    },
+    {
+      .ext = NULL,
+      .mime = NULL
+    },
+  };
+  struct TALER_MHD_Spa *spa = cls;
+  int fd;
+  struct stat sb;
+  struct MHD_Response *zresponse = NULL;
+  struct MHD_Response *response;
+  const char *ext;
+  const char *mime;
+
+  fd = open (dn,
+             O_RDONLY);
+  if (-1 == fd)
+  {
+    GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+                              "open",
+                              dn);
+    return GNUNET_SYSERR;
+  }
+  if (0 !=
+      fstat (fd,
+             &sb))
+  {
+    GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+                              "open",
+                              dn);
+    GNUNET_break (0 == close (fd));
+    return GNUNET_SYSERR;
+  }
+
+  mime = NULL;
+  ext = strrchr (dn, '.');
+  if (NULL == ext)
+  {
+    GNUNET_break (0 == close (fd));
+    return GNUNET_OK;
+  }
+  ext++;
+  for (unsigned int i = 0; NULL != mime_map[i].ext; i++)
+    if (0 == strcasecmp (ext,
+                         mime_map[i].ext))
+    {
+      mime = mime_map[i].mime;
+      break;
+    }
+
+  {
+    void *in;
+    ssize_t r;
+    size_t csize;
+
+    in = GNUNET_malloc_large (sb.st_size);
+    if (NULL == in)
+    {
+      GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                           "malloc");
+      GNUNET_break (0 == close (fd));
+      return GNUNET_SYSERR;
+    }
+    r = read (fd,
+              in,
+              sb.st_size);
+    if ( (-1 == r) ||
+         (sb.st_size != (size_t) r) )
+    {
+      GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+                                "read",
+                                dn);
+      GNUNET_free (in);
+      GNUNET_break (0 == close (fd));
+      return GNUNET_SYSERR;
+    }
+    csize = (size_t) r;
+    if (MHD_YES ==
+        TALER_MHD_body_compress (&in,
+                                 &csize))
+    {
+      zresponse = MHD_create_response_from_buffer (csize,
+                                                   in,
+                                                   MHD_RESPMEM_MUST_FREE);
+      if (NULL != zresponse)
+      {
+        if (MHD_NO ==
+            MHD_add_response_header (zresponse,
+                                     MHD_HTTP_HEADER_CONTENT_ENCODING,
+                                     "deflate"))
+        {
+          GNUNET_break (0);
+          MHD_destroy_response (zresponse);
+          zresponse = NULL;
+        }
+        if (NULL != mime)
+          GNUNET_break (MHD_YES ==
+                        MHD_add_response_header (zresponse,
+                                                 MHD_HTTP_HEADER_CONTENT_TYPE,
+                                                 mime));
+      }
+    }
+    else
+    {
+      GNUNET_free (in);
+    }
+  }
+
+  response = MHD_create_response_from_fd (sb.st_size,
+                                          fd);
+  if (NULL == response)
+  {
+    GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+                              "open",
+                              dn);
+    GNUNET_break (0 == close (fd));
+    if (NULL != zresponse)
+    {
+      MHD_destroy_response (zresponse);
+      zresponse = NULL;
+    }
+    return GNUNET_SYSERR;
+  }
+  if (NULL != mime)
+    GNUNET_break (MHD_YES ==
+                  MHD_add_response_header (response,
+                                           MHD_HTTP_HEADER_CONTENT_TYPE,
+                                           mime));
+
+  {
+    struct WebuiFile *w;
+    const char *fn;
+
+    fn = strrchr (dn, '/');
+    GNUNET_assert (NULL != fn);
+    w = GNUNET_new (struct WebuiFile);
+    w->path = GNUNET_strdup (fn + 1);
+    w->response = response;
+    w->zresponse = zresponse;
+    GNUNET_CONTAINER_DLL_insert (spa->webui_head,
+                                 spa->webui_tail,
+                                 w);
+  }
+  return GNUNET_OK;
+}
+
+
+struct TALER_MHD_Spa *
+TALER_MHD_spa_load (const char *dir)
+{
+  struct TALER_MHD_Spa *spa;
+  char *dn;
+
+  {
+    char *path;
+
+    path = GNUNET_OS_installation_get_path (GNUNET_OS_IPK_DATADIR);
+    if (NULL == path)
+    {
+      GNUNET_break (0);
+      return NULL;
+    }
+    GNUNET_asprintf (&dn,
+                     "%s%s",
+                     path,
+                     dir);
+    GNUNET_free (path);
+  }
+  spa = GNUNET_new (struct TALER_MHD_Spa);
+  if (-1 ==
+      GNUNET_DISK_directory_scan (dn,
+                                  &build_webui,
+                                  spa))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Failed to load WebUI from `%s'\n",
+                dn);
+    GNUNET_free (dn);
+    TALER_MHD_spa_free (spa);
+    return NULL;
+  }
+  GNUNET_free (dn);
+  return spa;
+}
+
+
+void
+TALER_MHD_spa_free (struct TALER_MHD_Spa *spa)
+{
+  struct WebuiFile *w;
+
+  while (NULL != (w = spa->webui_head))
+  {
+    GNUNET_CONTAINER_DLL_remove (spa->webui_head,
+                                 spa->webui_tail,
+                                 w);
+    if (NULL != w->response)
+    {
+      MHD_destroy_response (w->response);
+      w->response = NULL;
+    }
+    if (NULL != w->zresponse)
+    {
+      MHD_destroy_response (w->zresponse);
+      w->zresponse = NULL;
+    }
+    GNUNET_free (w->path);
+    GNUNET_free (w);
+  }
+  GNUNET_free (spa);
+}