webcit-ng/server/forum_view.c

   1 // The code in here feeds messages out as JSON to the client browser.  It is currently being used
   2 // for the forum view, but as we implement other views we'll probably reuse a lot of what's here.
   3 //
   4 // Copyright (c) 1996-2022 by the citadel.org team
   5 //
   6 // This program is open source software.  Use, duplication, or
   7 // disclosure are subject to the GNU General Public License v3.
   8
   9 #include "webcit.h"
  10
  11 // Commands we need to send to Citadel Server before we begin rendering forum view.
  12 // These are common to flat and threaded views.
  13 void setup_for_forum_view(struct ctdlsession *c) {
  14         char buf[1024];
  15         ctdl_printf(c, "MSGP text/html|text/plain");    // Declare the MIME types we know how to render
  16         ctdl_readline(c, buf, sizeof(buf));             // Ignore the response
  17         ctdl_printf(c, "MSGP dont_decode");             // Tell the server we will decode base64/etc client-side
  18         ctdl_readline(c, buf, sizeof(buf));             // Ignore the response
  19 }
  20
  21
  22 // Convenience function for json_render_one_message()
  23 // Converts a string of comma-separated recipients into a JSON Array
  24 JsonValue *json_tokenize_recipients(const char *Key, long keylen, char *recp) {
  25         char tokbuf[1024];
  26
  27         JsonValue *j = NewJsonArray(Key, keylen);
  28         int num_recp = num_tokens(recp, ',');
  29         for (int i=0; i<num_recp; ++i) {
  30                 extract_token(tokbuf, recp, i, ',', sizeof(tokbuf));
  31                 string_trim(tokbuf);
  32                 JsonArrayAppend(j, NewJsonPlainString(HKEY("r"), tokbuf, strlen(tokbuf)));
  33         }
  34         return(j);
  35 }
  36
  37
  38 // Fetch a single message and return it in JSON format for client-side rendering
  39 void json_render_one_message(struct http_transaction *h, struct ctdlsession *c, long msgnum) {
  40         StrBuf *raw_msg = NULL;
  41         StrBuf *sanitized_msg = NULL;
  42         char buf[1024];
  43         char content_transfer_encoding[1024] = { 0 };
  44         char content_type[1024] = { 0 };
  45         char datetime[128] = { 0 };
  46         int message_originated_locally = 0;
  47
  48         setup_for_forum_view(c);
  49
  50         ctdl_printf(c, "MSG4 %ld", msgnum);
  51         ctdl_readline(c, buf, sizeof(buf));
  52         if (buf[0] != '1') {
  53                 do_404(h);
  54                 return;
  55         }
  56
  57         JsonValue *j = NewJsonObject(HKEY("message"));
  58         JsonObjectAppend(j, NewJsonNumber(HKEY("msgnum"), msgnum));
  59
  60         while ((ctdl_readline(c, buf, sizeof(buf)) >= 0) && (strcmp(buf, "text")) && (strcmp(buf, "000"))) {
  61                 utf8ify_rfc822_string(&buf[5]);
  62
  63                 // citadel header parsing here
  64                 if (!strncasecmp(buf, "from=", 5)) {
  65                         JsonObjectAppend(j, NewJsonPlainString(HKEY("from"), &buf[5], -1));
  66                 }
  67                 else if (!strncasecmp(buf, "rfca=", 5)) {
  68                         JsonObjectAppend(j, NewJsonPlainString(HKEY("rfca"), &buf[5], -1));
  69                 }
  70                 else if (!strncasecmp(buf, "time=", 5)) {
  71                         JsonObjectAppend(j, NewJsonNumber(HKEY("time"), atol(&buf[5])));
  72                 }
  73                 else if (!strncasecmp(buf, "locl=", 5)) {
  74                         message_originated_locally = 1;
  75                 }
  76                 else if (!strncasecmp(buf, "subj=", 5)) {
  77                         JsonObjectAppend(j, NewJsonPlainString(HKEY("subj"), &buf[5], -1));
  78                 }
  79                 else if (!strncasecmp(buf, "msgn=", 5)) {
  80                         JsonObjectAppend(j, NewJsonPlainString(HKEY("msgn"), &buf[5], -1));
  81                 }
  82                 else if (!strncasecmp(buf, "wefw=", 5)) {
  83                         JsonObjectAppend(j, NewJsonPlainString(HKEY("wefw"), &buf[5], -1));
  84                 }
  85                 else if (!strncasecmp(buf, "rcpt=", 5)) {
  86                         JsonObjectAppend(j, json_tokenize_recipients(HKEY("rcpt"), &buf[5]));
  87                 }
  88                 else if (!strncasecmp(buf, "cccc=", 5)) {
  89                         JsonObjectAppend(j, json_tokenize_recipients(HKEY("cccc"), &buf[5]));
  90                 }
  91         }
  92         JsonObjectAppend(j, NewJsonNumber(HKEY("locl"), message_originated_locally));
  93
  94         if (!strcmp(buf, "text")) {
  95                 while ((ctdl_readline(c, buf, sizeof(buf)) >= 0) && (strcmp(buf, "")) && (strcmp(buf, "000"))) {
  96                         // rfc822 header parsing here
  97                         if (!strncasecmp(buf, "Content-transfer-encoding:", 26)) {
  98                                 strcpy(content_transfer_encoding, &buf[26]);
  99                                 string_trim(content_transfer_encoding);
 100                         }
 101                         if (!strncasecmp(buf, "Content-type:", 13)) {
 102                                 strcpy(content_type, &buf[13]);
 103                                 string_trim(content_type);
 104                         }
 105                 }
 106                 if (!strcmp(buf, "000")) {              // if we have an empty message, don't try to read further
 107                         raw_msg = NULL;
 108                 }
 109                 else {
 110                         raw_msg = ctdl_readtextmsg(c);
 111                 }
 112         }
 113         else {
 114                 raw_msg = NULL;
 115         }
 116
 117         if (raw_msg) {
 118                 // These are the encodings we know how to handle.  Decode in-place.
 119
 120                 if (!strcasecmp(content_transfer_encoding, "base64")) {
 121                         StrBufDecodeBase64(raw_msg);
 122                 }
 123                 if (!strcasecmp(content_transfer_encoding, "quoted-printable")) {
 124                         StrBufDecodeQP(raw_msg);
 125                 }
 126
 127                 // At this point, raw_msg contains the decoded message.
 128                 // Now run through the renderers we have available.
 129
 130                 if (!strncasecmp(content_type, "text/html", 9)) {
 131                         sanitized_msg = html2html("UTF-8", 0, c->room, msgnum, raw_msg);
 132                 }
 133                 else if (!strncasecmp(content_type, "text/plain", 10)) {
 134                         sanitized_msg = text2html("UTF-8", 0, c->room, msgnum, raw_msg);
 135                 }
 136                 else if (!strncasecmp(content_type, "text/x-citadel-variformat", 25)) {
 137                         sanitized_msg = variformat2html(raw_msg);
 138                 }
 139                 else {
 140                         sanitized_msg = NewStrBufPlain(HKEY("<i>No renderer for this content type</i><br>"));
 141                         syslog(LOG_WARNING, "forum_view: no renderer for content type %s", content_type);
 142                 }
 143                 FreeStrBuf(&raw_msg);
 144
 145                 // If sanitized_msg is not NULL, we have rendered the message and can output it.
 146                 if (sanitized_msg) {
 147                         JsonObjectAppend(j, NewJsonString(HKEY("text"), sanitized_msg, NEWJSONSTRING_SMASHBUF));
 148                 }
 149                 else {
 150                         syslog(LOG_WARNING, "forum_view: message %ld of content type %s converted to NULL", msgnum, content_type);
 151                 }
 152         }
 153
 154         StrBuf *sj = NewStrBuf();
 155         SerializeJson(sj, j, 1);        // '1' == free the source object
 156
 157         add_response_header(h, strdup("Content-type"), strdup("application/json"));
 158         h->response_code = 200;
 159         h->response_string = strdup("OK");
 160         h->response_body_length = StrLength(sj);
 161         h->response_body = SmashStrBuf(&sj);
 162 }