Added a "fallback" option to be used with the "share" action.

It allows proceeding to another action if a file isn't available.

An example:

    {
        "share": "/data/www/",

        "fallback": {
            "pass": "applications/php"
        }
    }

In the example above, an attempt is made first to serve a request with
a file from the "/data/www/" directory.  If there's no such file, the
request is passed to the "php" application.

Fallback actions may be nested:

    {
        "share": "/data/www/",

        "fallback": {
            "share": "/data/cache/",

            "fallback": {
                "proxy": "http://127.0.0.1:9000"
            }
        }
    }

1 files changed, 13 insertions, 0 deletions

diff --git a/src/nxt_http_static.c b/src/nxt_http_static.c
index 44132859..46ae57a7 100644
--- a/src/nxt_http_static.c
+++ b/src/nxt_http_static.c
@@ -49,6 +49,10 @@ nxt_http_static_handler(nxt_task_t *task, nxt_http_request_t *r,
     if (nxt_slow_path(!nxt_str_eq(r->method, "GET", 3))) {
 
         if (!nxt_str_eq(r->method, "HEAD", 4)) {
+            if (action->u.fallback != NULL) {
+                return action->u.fallback;
+            }
+
             nxt_http_request_error(task, r, NXT_HTTP_METHOD_NOT_ALLOWED);
             return NULL;
         }
@@ -123,6 +127,10 @@ nxt_http_static_handler(nxt_task_t *task, nxt_http_request_t *r,
             break;
         }
 
+        if (level == NXT_LOG_ERR && action->u.fallback != NULL) {
+            return action->u.fallback;
+        }
+
         if (status != NXT_HTTP_NOT_FOUND) {
             nxt_log(task, level, "open(\"%FN\") failed %E", f->name, f->error);
         }
@@ -222,8 +230,13 @@ nxt_http_static_handler(nxt_task_t *task, nxt_http_request_t *r,
         nxt_file_close(task, f);
 
         if (nxt_slow_path(!nxt_is_dir(&fi))) {
+            if (action->u.fallback != NULL) {
+                return action->u.fallback;
+            }
+
             nxt_log(task, NXT_LOG_ERR, "\"%FN\" is not a regular file",
                     f->name);
+
             nxt_http_request_error(task, r, NXT_HTTP_NOT_FOUND);
             return NULL;
         }