CLI: print extra headers in structured output

This is based on a patch from Johan Parin [1], which is in turn
responding to a bug report / feature requiest from Jan Malkhovski.

The update to the structured output documented in schemata is intended
to be upward compatible, so the format version stays the same

[1]: id:20191116162723.18343-1-johan.parin@gmail.com
[2]: id:87h8sdemnr.fsf@oxij.org

devel/schemata

@@ -145,9 +145,11 @@ headers = {
     Cc?:            string,
     Bcc?:           string,
     Reply-To?:      string,
-    Date:           string
+    Date:           string,
+    extra_header_pair*
 }
 
+extra_header_pair=  (header_name: string)
 # Encryption status (format_part_sprinter)
 encstatus = [{status: "good"|"bad"}]
 

notmuch-show.c

@@ -209,6 +209,30 @@ _is_from_line (const char *line)
 	return 0;
 }
 
+/* Output extra headers if configured with the `show.extra_headers'
+ * configuration option
+ */
+static void
+format_extra_headers_sprinter (sprinter_t *sp, GMimeMessage *message)
+{
+    GMimeHeaderList *header_list = g_mime_object_get_header_list (GMIME_OBJECT (message));
+
+    for (notmuch_config_values_t *extra_headers = notmuch_config_get_values (
+	     sp->notmuch, NOTMUCH_CONFIG_EXTRA_HEADERS);
+	 notmuch_config_values_valid (extra_headers);
+	 notmuch_config_values_move_to_next (extra_headers)) {
+	GMimeHeader *header;
+	const char *header_name = notmuch_config_values_get (extra_headers);
+
+	header = g_mime_header_list_get_header (header_list, header_name);
+	if (header == NULL)
+	    continue;
+
+	sp->map_key (sp, g_mime_header_get_name (header));
+	sp->string (sp, g_mime_header_get_value (header));
+    }
+}
+
 void
 format_headers_sprinter (sprinter_t *sp, GMimeMessage *message,
 			 bool reply, const _notmuch_message_crypto_t *msg_crypto)
@@ -269,6 +293,8 @@ format_headers_sprinter (sprinter_t *sp, GMimeMessage *message,
 	sp->string (sp, g_mime_message_get_date_string (sp, message));
     }
 
+    /* Output extra headers the user has configured, if any */
+    format_extra_headers_sprinter (sp, message);
     sp->end (sp);
     talloc_free (local);
 }

test/T160-json.sh

@@ -156,4 +156,46 @@ EOF
 output=$(notmuch show --format=json --body=false --format-version=2 id:message-id@example.com)
 test_expect_equal_json "$output" "$(cat EXPECTED)"
 
+test_begin_subtest "show extra headers"
+add_message "[subject]=\"extra-headers\"" "[date]=\"Sat, 01 Jan 2000 12:00:00 -0000\"" "[in-reply-to]=\"<parent@notmuch-test-suite>\"" "[body]=\"extra-headers test\""\
+	   "[header]=\"Received: from mail.example.com (mail.example.com [1.1.1.1])
+	by mail.notmuchmail.org (some MTA) with ESMTP id 12345678
+	for <test_suite_other@notmuchmail.org>; Sat, 10 Apr 2010 07:54:51 -0400 (EDT)\"" \
+
+notmuch config set show.extra_headers "in-reply-to;received"
+output=$(notmuch show --format=json --body=false id:${gen_msg_id} | notmuch_json_show_sanitize)
+cat <<EOF > EXPECTED
+[
+    [
+        [
+            {
+                "crypto": {},
+                "date_relative": "2000-01-01",
+                "excluded": false,
+                "filename": [
+                    "YYYYY"
+                ],
+                "headers": {
+                    "Date": "Sat, 01 Jan 2000 12:00:00 +0000",
+                    "From": "Notmuch Test Suite <test_suite@notmuchmail.org>",
+                    "In-Reply-To": "<parent@notmuch-test-suite>",
+                    "Received": "from mail.example.com (mail.example.com [1.1.1.1])\tby mail.notmuchmail.org (some MTA) with ESMTP id 12345678\tfor <test_suite_other@notmuchmail.org>; Sat, 10 Apr 2010 07:54:51 -0400 (EDT)",
+                    "Subject": "extra-headers",
+                    "To": "Notmuch Test Suite <test_suite@notmuchmail.org>"
+                },
+                "id": "XXXXX",
+                "match": true,
+                "tags": [
+                    "inbox",
+                    "unread"
+                ],
+                "timestamp": 946728000
+            },
+            []
+        ]
+    ]
+]
+EOF
+test_expect_equal_json "${output}" "$(cat EXPECTED)"
+
 test_done

test/T170-sexp.sh

@@ -47,4 +47,18 @@ filename=$(notmuch search --output=files "id:$id")
 attachment_length=$(( $(base64 $NOTMUCH_SRCDIR/test/README | wc -c) - 1 ))
 test_expect_equal "$output" "((((:id \"$id\" :match t :excluded nil :filename (\"$filename\") :timestamp 946728000 :date_relative \"2000-01-01\" :tags (\"inbox\") :body ((:id 1 :content-type \"multipart/mixed\" :content ((:id 2 :content-type \"text/plain\" :content \"This is a test message with inline attachment with a filename\") (:id 3 :content-type \"application/octet-stream\" :content-disposition \"inline\" :filename \"README\" :content-transfer-encoding \"base64\" :content-length $attachment_length)))) :crypto () :headers (:Subject \"sexp-show-inline-attachment-filename\" :From \"Notmuch Test Suite <test_suite@notmuchmail.org>\" :To \"test_suite@notmuchmail.org\" :Date \"Sat, 01 Jan 2000 12:00:00 +0000\")) ())))"
 
+test_begin_subtest "show extra headers"
+add_message "[subject]=\"extra-headers\"" "[date]=\"Sat, 01 Jan 2000 12:00:00 -0000\"" "[in-reply-to]=\"<parent@notmuch-test-suite>\"" "[body]=\"extra-headers test\""\
+	   "[header]=\"Received: from mail.example.com (mail.example.com [1.1.1.1])
+	by mail.notmuchmail.org (some MTA) with ESMTP id 12345678
+	for <test_suite_other@notmuchmail.org>; Sat, 10 Apr 2010 07:54:51 -0400 (EDT)\"" \
+
+notmuch config set show.extra_headers "in-reply-to;received"
+notmuch show --format=sexp --body=false id:${gen_msg_id} | \
+    notmuch_dir_sanitize | sed 's/msg-[0-9]*/MSG/g'> OUTPUT
+cat <<EOF > EXPECTED
+((((:id "MSG@notmuch-test-suite" :match t :excluded nil :filename ("MAIL_DIR/MSG") :timestamp 946728000 :date_relative "2000-01-01" :tags ("inbox" "unread") :crypto () :headers (:Subject "extra-headers" :From "Notmuch Test Suite <test_suite@notmuchmail.org>" :To "Notmuch Test Suite <test_suite@notmuchmail.org>" :Date "Sat, 01 Jan 2000 12:00:00 +0000" :In-Reply-To "<parent@notmuch-test-suite>" :Received "from mail.example.com (mail.example.com [1.1.1.1])\011by mail.notmuchmail.org (some MTA) with ESMTP id 12345678\011for <test_suite_other@notmuchmail.org>; Sat, 10 Apr 2010 07:54:51 -0400 (EDT)")) ())))
+EOF
+test_expect_equal_file EXPECTED OUTPUT
+
 test_done