feature: add a priority field to match routes with the same path in t… (#35)

* feature: add a priority field to match routes with the same path in the order of priority.

Fix #31.

* feature: supported priority for prefix matching.

* doc.

Author: membphis

README.md

@@ -7,7 +7,7 @@ This is Lua-Openresty implementation library base on FFI for [rax](https://githu
 
 This project depends on [lua-resty-ipmatcher](https://github.com/iresty/lua-resty-ipmatcher).
 
-This project has been working in projects microservices API gateway [Apache APISIX](https://github.com/apache/incubator-apisix).
+This project has been working in microservices API gateway [Apache APISIX](https://github.com/apache/incubator-apisix).
 
 The project is open sourced by Shenzhen [ZhiLiu](https://www.iresty.com/) Technology Company. In addition to this open source version, our company also provides a more powerful and performing commercial version, and provides technical support. If you are interested in our commercial version, please contact us. email: [[email protected]]([email protected]) .
 
@@ -83,6 +83,7 @@ The attributes of each element may contain these:
 |methods    |option  |A list of method name. Here is full valid method list: "GET", "POST", "PUT", "DELETE", "PATCH", "HEAD", "OPTIONS", "CONNECT" and "TRACE".|{"GET", "POST"}|
 |vars       |option  |A list of `{var, operator, val}`. For example: {{var, operator, val}, {var, operator, val}, ...}, `{"arg_name", "==", "json"}` means the value of argument `name` expect to `json`. Here is the full [Operator List](#operator-list).|{{"arg_name", "==", "json"}, {"arg_age", ">", 18}}|
 |filter_fun |option  |User defined filter function, We can use it to achieve matching logic for special scenes. `radixtree` will pass `vars` and other arguments when matching route.|function(vars) return vars["arg_name"] == "json" end|
+|priority      |option  |Routing priority, default is 0.|priority = 100|
 |metadata   |option  |Will return this field if using `rx:match` to match route.||
 |handler    |option  |Will call this function using `rx:dispatch` to match route.||
 

lib/resty/radixtree.lua

@@ -25,6 +25,7 @@ local cur_level   = ngx.config.subsystem == "http" and
                     require("ngx.errlog").get_sys_filter_level()
 local ngx_var     = ngx.var
 local re_find     = ngx.re.find
+local sort_tab    = table.sort
 local empty_table = {}
 
 
@@ -98,7 +99,7 @@ for i, name in ipairs({"GET", "POST", "PUT", "DELETE", "PATCH", "HEAD",
 end
 
 
-local _M = { _VERSION = 0.02 }
+local _M = { _VERSION = 1.7 }
 
 
 -- only work under lua51 or luajit
@@ -133,6 +134,11 @@ end
 local mt = { __index = _M, __gc = gc_free }
 
 
+local function sort_route(route_a, route_b)
+    return (route_a.priority or 0) > (route_b.priority or 0)
+end
+
+
 local function insert_route(self, opts)
     local path = opts.path
     opts = clone_tab(opts)
@@ -146,6 +152,7 @@ local function insert_route(self, opts)
             insert_tab(self.hash_path[path], opts)
         end
 
+        sort_tab(self.hash_path[path], sort_route)
         return true
     end
 
@@ -156,6 +163,7 @@ local function insert_route(self, opts)
         local routes = self.match_data[idx]
         if routes and routes[1].path == path then
             insert_tab(routes, opts)
+            sort_tab(routes, sort_route)
             return true
         end
     end
@@ -286,6 +294,7 @@ function pre_insert_route(self, path, route)
     route_opts.method   = bit_methods
     route_opts.vars     = route.vars
     route_opts.filter_fun   = route.filter_fun
+    route_opts.priority = route.priority or 0
 
     local err
     local remote_addrs = route.remote_addrs

t/path.t

@@ -69,6 +69,7 @@ nil
 nil
 
 
+
 === TEST 3: multiple path with overlap
 --- config
     location /t {

t/priority.t

@@ -0,0 +1,119 @@
+use t::RX 'no_plan';
+
+repeat_each(1);
+run_tests();
+
+__DATA__
+
+=== TEST 1: multiple route (same priority)
+--- config
+    location /t {
+        content_by_lua_block {
+            local radix = require("resty.radixtree")
+            local rx = radix.new({
+                {
+                    paths = {"/aa"},
+                    metadata = "metadata 1",
+                },
+                {
+                    paths = {"/aa"},
+                    metadata = "metadata 2",
+                },
+            })
+
+            ngx.say(rx:match("/aa"))
+        }
+    }
+--- request
+GET /t
+--- no_error_log
+[error]
+--- response_body
+metadata 1
+
+
+
+=== TEST 2: multiple route (different priority)
+--- config
+    location /t {
+        content_by_lua_block {
+            local radix = require("resty.radixtree")
+            local rx = radix.new({
+                {
+                    paths = {"/aa"},
+                    metadata = "metadata 1",
+                    priority = 1,
+                },
+                {
+                    paths = {"/aa"},
+                    metadata = "metadata 2",
+                    priority = 2,
+                },
+            })
+
+            ngx.say(rx:match("/aa"))
+        }
+    }
+--- request
+GET /t
+--- no_error_log
+[error]
+--- response_body
+metadata 2
+
+
+
+=== TEST 3: multiple route (same priority)
+--- config
+    location /t {
+        content_by_lua_block {
+            local radix = require("resty.radixtree")
+            local rx = radix.new({
+                {
+                    paths = {"/aa*"},
+                    metadata = "metadata 1",
+                },
+                {
+                    paths = {"/aa*"},
+                    metadata = "metadata 2",
+                },
+            })
+
+            ngx.say(rx:match("/aa/bb"))
+        }
+    }
+--- request
+GET /t
+--- no_error_log
+[error]
+--- response_body
+metadata 1
+
+
+
+=== TEST 4: multiple route (different priority)
+--- config
+    location /t {
+        content_by_lua_block {
+            local radix = require("resty.radixtree")
+            local rx = radix.new({
+                {
+                    paths = {"/aa*"},
+                    metadata = "metadata 1",
+                },
+                {
+                    paths = {"/aa*"},
+                    metadata = "metadata 2",
+                    priority = 1,
+                },
+            })
+
+            ngx.say(rx:match("/aa/bb"))
+        }
+    }
+--- request
+GET /t
+--- no_error_log
+[error]
+--- response_body
+metadata 2