MINOR: added possibility to change HTTP headers that are sent to mirror URL

The function spoa_msg_arg_hdrs() has been added, which allows changing the
type of the SPOE argument 'arg_hdrs' to a string (until now, that argument
could only be binary).  In this way, the use of the regsub() converter is
enabled in that argument, so that it is now possible to change the HTTP
headers that are sent to the mirror URL.

For example, instead of:

  args arg_method=method arg_path=url arg_ver=req.ver arg_hdrs=req.hdrs_bin arg_body=req.body

, the following can be used:

  args arg_method=method arg_path=url arg_ver=req.ver arg_hdrs=req.hdrs,regsub(foo,bar) arg_body=req.body

Version of the program changed to v1.2.18.

Author: zaga00

README

@@ -162,6 +162,21 @@ configuration file:
   # /path-to/haproxy -f haproxy.cfg
 
 
+Note related to SPOE configuration: in the 'spoe-message' section (in the
+given example, this section is called 'mirror') the 'args' keyword must always
+(and only) contain the following arguments (after the sign '=' there is a
+permitted argument type):
+
+  arg_method=STR arg_path=STR arg_ver=STR arg_hdrs=(BIN|STR) arg_body=BIN
+
+'arg_hdrs' can have a binary (req.hdrs_bin) or string (req.hdrs) data type
+argument specified.  In case we want to make some changes in the HTTP headers
+that are sent to the mirror URL, then we will use the string data type for
+that argument to which we can add the regsub() converter, as in the example:
+
+  .. arg_hdrs=req.hdrs,regsub(foo,bar)
+
+
 4. Known bugs and limitations
 ------------------------------------------------------------------------
 

VERSION

@@ -1 +1 @@
-1.2.17
+1.2.18

src/.build-counter

@@ -1 +1 @@
-2513
+2519

src/spoa-message.c

@@ -316,6 +316,72 @@ static int spoa_msg_arg_hdrs_bin(struct spoe_frame *frame, const char *buf, cons
 }
 
 
+/***
+ * NAME
+ *   spoa_msg_arg_hdrs -
+ *
+ * ARGUMENTS
+ *   frame -
+ *   buf   -
+ *   end   -
+ *   hdrs  -
+ *
+ * DESCRIPTION
+ *   -
+ *
+ * RETURN VALUE
+ *   -
+ */
+static int spoa_msg_arg_hdrs(struct spoe_frame *frame, const char *buf, const char *end, struct list *hdrs)
+{
+	struct buffer *hdr = NULL, *hdr_back;
+	const char    *ptr;
+	int            i, retval = FUNC_RET_OK;
+
+	DBG_FUNC(FW_PTR, "%p, %p, %p, %p", frame, buf, end, hdrs);
+
+	/* Build the HTTP headers. */
+	for (i = 0; buf < end; i++) {
+		/* Find end of the HTTP header (CRLF). */
+		for (ptr = buf; ptr < end; ptr++)
+			if (TEST_OR2(*ptr, '\r', '\n'))
+				break;
+
+		/*
+		 * Can the HTTP header be empty?
+		 * In that case, this block is skipped.
+		 */
+		if (ptr != buf) {
+			if (_NULL(hdr = buffer_alloc(cfg.max_frame_size, buf, ptr - buf, NULL)))
+				break;
+
+			F_DBG(SPOA, frame, "header[%d]: <%.*s>", i, (int)hdr->len, hdr->ptr);
+
+			LIST_ADDQ(hdrs, &(hdr->list));
+		}
+
+		/* Skip the end of the HTTP header (CRLF). */
+		for (buf = ptr; buf < end; buf++)
+			if (TEST_NAND2(*buf, '\r', '\n'))
+				break;
+	}
+
+	/* In the case of a fault, the allocated memory is released. */
+	if (_ERROR(retval) || ((i > 0) && _NULL(hdr))) {
+		buffer_ptr_free(&hdr);
+
+		list_for_each_entry_safe(hdr, hdr_back, hdrs, list) {
+			LIST_DEL(&(hdr->list));
+			buffer_ptr_free(&hdr);
+		}
+
+		retval = FUNC_RET_ERROR;
+	}
+
+	DBG_RETURN_INT(retval);
+}
+
+
 /***
  * NAME
  *   spoa_msg_mirror -
@@ -373,6 +439,17 @@ int spoa_msg_mirror(struct spoe_frame *frame, const char **buf, const char *end)
 				mir_ptr = &(mir->path);
 			else if ((len == STR_SIZE(SPOE_MSG_ARG_VER)) && (memcmp(str, STR_ADDRSIZE(SPOE_MSG_ARG_VER)) == 0))
 				mir_ptr = &(mir->version);
+			else if ((len == STR_SIZE(SPOE_MSG_ARG_HDRS)) && (memcmp(str, STR_ADDRSIZE(SPOE_MSG_ARG_HDRS)) == 0)) {
+				if (!LIST_ISEMPTY(&(mir->hdrs))) {
+					f_log(frame, _E("arg[%d] '%.*s': Duplicated argument"), i, (int)len, str);
+
+					retval = FUNC_RET_ERROR;
+				}
+				else
+					retval = spoa_msg_arg_hdrs(frame, data.chk.ptr, data.chk.ptr + data.chk.len - 1, &(mir->hdrs));
+
+				continue;
+			}
 			else {
 				f_log(frame, _W("Unknown argument, ignored: '%.*s'"), (int)len, str);