lib-http: http_client_request_add_header() - Replace existing header

If header with the same key already exists, just replace the value.
HTTP supports having multiple headers with the same key only when they
can be rewritten into a single comma-separated header. So practically
there's no reason for lib-http to need to support adding multiple
headers. Replacing an existing value is more useful generally.

diff --git a/src/lib-http/http-client-request.c b/src/lib-http/http-client-request.c
index e50d0d551575bce4bd25c300059bdc632dc55b9c..6847b327b0823e3cc00850559a0cbf9c7f01c1cf 100644 (file)
--- a/src/lib-http/http-client-request.c
+++ b/src/lib-http/http-client-request.c
@@ -364,6 +364,8 @@ http_client_request_lookup_header_pos(struct http_client_request *req,
 void http_client_request_add_header(struct http_client_request *req,
                                    const char *key, const char *value)
 {
+       size_t key_pos, value_pos, next_pos;
+
        i_assert(req->state == HTTP_REQUEST_STATE_NEW ||
                 /* allow calling for retries */
                 req->state == HTTP_REQUEST_STATE_GOT_RESPONSE ||
@@ -410,7 +412,14 @@ void http_client_request_add_header(struct http_client_request *req,
        }
        if (req->headers == NULL)
                req->headers = str_new(default_pool, 256);
-       str_printfa(req->headers, "%s: %s\r\n", key, value);
+       if (!http_client_request_lookup_header_pos(req, key, &key_pos,
+                                                  &value_pos, &next_pos))
+               str_printfa(req->headers, "%s: %s\r\n", key, value);
+       else {
+               /* don't delete CRLF */
+               size_t old_value_len = next_pos - value_pos - 2;
+               str_replace(req->headers, value_pos, old_value_len, value);
+       }
 }
 
 void http_client_request_remove_header(struct http_client_request *req,

diff --git a/src/lib-http/http-client.h b/src/lib-http/http-client.h
index bc63cc1bf9afab34095251b341a0312662794776..74733502a7e780fe19d80a312396862513f68ea6 100644 (file)
--- a/src/lib-http/http-client.h
+++ b/src/lib-http/http-client.h
@@ -280,7 +280,8 @@ void http_client_request_set_urgent(struct http_client_request *req);
 void http_client_request_set_preserve_exact_reason(struct http_client_request *req);
 
 /* add a custom header to the request. This can override headers that are
-   otherwise created implicitly. */
+   otherwise created implicitly. If the same header key was already added,
+   the value is replaced. */
 void http_client_request_add_header(struct http_client_request *req,
                                    const char *key, const char *value);
 /* remove a header added earlier. This has no influence on implicitly created