Remove session-cookie-hash annotation

rootfs/etc/nginx/lua/balancer/sticky.lua

@@ -2,29 +2,20 @@ local balancer_resty = require("balancer.resty")
 local resty_chash = require("resty.chash")
 local util = require("util")
 local ck = require("resty.cookie")
+local math = require("math")
 
 local _M = balancer_resty:new({ factory = resty_chash, name = "sticky" })
 local DEFAULT_COOKIE_NAME = "route"
 
-local function get_digest_func(hash)
-  local digest_func = util.md5_digest
-  if hash == "sha1" then
-    digest_func = util.sha1_digest
-  end
-  return digest_func
-end
-
 function _M.cookie_name(self)
   return self.cookie_session_affinity.name or DEFAULT_COOKIE_NAME
 end
 
 function _M.new(self, backend)
   local nodes = util.get_nodes(backend.endpoints)
-  local digest_func = get_digest_func(backend["sessionAffinityConfig"]["cookieSessionAffinity"]["hash"])
 
   local o = {
     instance = self.factory:new(nodes),
-    digest_func = digest_func,
     traffic_shaping_policy = backend.trafficShapingPolicy,
     alternative_backends = backend.alternativeBackends,
     cookie_session_affinity = backend["sessionAffinityConfig"]["cookieSessionAffinity"]
@@ -34,15 +25,6 @@ function _M.new(self, backend)
   return o
 end
 
-local function encrypted_endpoint_string(self, endpoint_string)
-  local encrypted, err = self.digest_func(endpoint_string)
-  if err ~= nil then
-    ngx.log(ngx.ERR, err)
-  end
-
-  return encrypted
-end
-
 local function set_cookie(self, value)
   local cookie, err = ck:new()
   if not cookie then
@@ -86,8 +68,7 @@ function _M.balance(self)
 
   local key = cookie:get(self:cookie_name())
   if not key then
-    local random_str = string.format("%s.%s", ngx.now(), ngx.worker.pid())
-    key = encrypted_endpoint_string(self, random_str)
+    key = string.format("%s.%s.%s", ngx.now(), ngx.worker.pid(), math.random(999999))
 
     if self.cookie_session_affinity.locations then
       local locs = self.cookie_session_affinity.locations[ngx.var.host]
@@ -118,7 +99,6 @@ function _M.sync(self, backend)
   end
 
   self.cookie_session_affinity = backend.sessionAffinityConfig.cookieSessionAffinity
-  self.digest_func = get_digest_func(backend.sessionAffinityConfig.cookieSessionAffinity.hash)
 end
 
 return _M

rootfs/etc/nginx/lua/test/balancer/sticky_test.lua

@@ -68,26 +68,6 @@ describe("Sticky", function()
         assert.equal(sticky_balancer_instance:cookie_name(), default_cookie_name)
       end)
     end)
-
-    context("when backend specifies hash function", function()
-      it("returns an instance with the corresponding hash implementation", function()
-        local sticky_balancer_instance = sticky:new(test_backend)
-        local test_backend_hash_fn = test_backend.sessionAffinityConfig.cookieSessionAffinity.hash
-        local test_backend_hash_implementation = util[test_backend_hash_fn .. "_digest"]
-        assert.equal(sticky_balancer_instance.digest_func, test_backend_hash_implementation)
-      end)
-    end)
-
-    context("when backend does not specify hash function", function()
-      it("returns an instance with the default implementation (md5)", function()
-        local temp_backend = util.deepcopy(test_backend)
-        temp_backend.sessionAffinityConfig.cookieSessionAffinity.hash = nil
-        local sticky_balancer_instance = sticky:new(temp_backend)
-        local default_hash_fn = "md5"
-        local default_hash_implementation = util[default_hash_fn .. "_digest"]
-        assert.equal(sticky_balancer_instance.digest_func, default_hash_implementation)
-      end)
-    end)
   end)
 
   describe("balance()", function()
@@ -112,12 +92,9 @@ describe("Sticky", function()
       it("sets a cookie on the client", function()
         local s = {}
         cookie.new = function(self)
-          local test_backend_hash_fn = test_backend.sessionAffinityConfig.cookieSessionAffinity.hash
           local cookie_instance = {
             set = function(self, payload)
               assert.equal(payload.key, test_backend.sessionAffinityConfig.cookieSessionAffinity.name)
-              local expected_len = #util[test_backend_hash_fn .. "_digest"]("anything")
-              assert.equal(#payload.value, expected_len)
               assert.equal(payload.path, ngx.var.location_path)
               assert.equal(payload.domain, nil)
               assert.equal(payload.httponly, true)
@@ -141,12 +118,9 @@ describe("Sticky", function()
         ngx.var.https = "on"
         local s = {}
         cookie.new = function(self)
-          local test_backend_hash_fn = test_backend.sessionAffinityConfig.cookieSessionAffinity.hash
           local cookie_instance = {
             set = function(self, payload)
               assert.equal(payload.key, test_backend.sessionAffinityConfig.cookieSessionAffinity.name)
-              local expected_len = #util[test_backend_hash_fn .. "_digest"]("anything")
-              assert.equal(#payload.value, expected_len)
               assert.equal(payload.path, ngx.var.location_path)
               assert.equal(payload.domain, nil)
               assert.equal(payload.httponly, true)
@@ -177,12 +151,9 @@ describe("Sticky", function()
       it("does not set a cookie on the client", function()
         local s = {}
         cookie.new = function(self)
-          local test_backend_hash_fn = test_backend.sessionAffinityConfig.cookieSessionAffinity.hash
           local cookie_instance = {
             set = function(self, payload)
               assert.equal(payload.key, test_backend.sessionAffinityConfig.cookieSessionAffinity.name)
-              local expected_len = #util[test_backend_hash_fn .. "_digest"]("anything")
-              assert.equal(#payload.value, expected_len)
               assert.equal(payload.path, ngx.var.location_path)
               assert.equal(payload.domain, ngx.var.host)
               assert.equal(payload.httponly, true)

rootfs/etc/nginx/lua/test/balancer_test.lua

@@ -29,7 +29,7 @@ local function reset_backends()
         { address = "10.184.97.100", port = "8080", maxFails = 0, failTimeout = 0 },
         { address = "10.184.98.239", port = "8080", maxFails = 0, failTimeout = 0 },
       },
-      sessionAffinityConfig = { name = "", cookieSessionAffinity = { name = "", hash = "" } },
+      sessionAffinityConfig = { name = "", cookieSessionAffinity = { name = "" } },
     },
     { name = "my-dummy-app-1", ["load-balance"] = "round_robin", },
     { 
@@ -38,12 +38,12 @@ local function reset_backends()
     },
     {
       name = "my-dummy-app-3", ["load-balance"] = "ewma",
-      sessionAffinityConfig = { name = "cookie", cookieSessionAffinity = { name = "route", hash = "sha1" } }
+      sessionAffinityConfig = { name = "cookie", cookieSessionAffinity = { name = "route" } }
     },
     { name = "my-dummy-app-4", ["load-balance"] = "ewma", },
     {
       name = "my-dummy-app-5", ["load-balance"] = "ewma", ["upstream-hash-by"] = "$request_uri",
-      sessionAffinityConfig = { name = "cookie", cookieSessionAffinity = { name = "route", hash = "sha1" } }
+      sessionAffinityConfig = { name = "cookie", cookieSessionAffinity = { name = "route" } }
     },
   }
 end

rootfs/etc/nginx/lua/test/configuration_test.lua

@@ -10,7 +10,7 @@ function get_backends()
         {
             name = "my-dummy-backend-1", ["load-balance"] = "sticky",
             endpoints = { { address = "10.183.7.40", port = "8080", maxFails = 0, failTimeout = 0 } },
-            sessionAffinityConfig = { name = "cookie", cookieSessionAffinity = { name = "route", hash = "sha1" } },
+            sessionAffinityConfig = { name = "cookie", cookieSessionAffinity = { name = "route" } },
         },
         {
             name = "my-dummy-backend-2", ["load-balance"] = "ewma",

rootfs/etc/nginx/lua/util.lua

@@ -1,8 +1,5 @@
 local string_len = string.len
 local string_sub = string.sub
-local resty_str = require("resty.string")
-local resty_sha1 = require("resty.sha1")
-local resty_md5 = require("resty.md5")
 
 local _M = {}
 
@@ -18,30 +15,6 @@ function _M.get_nodes(endpoints)
   return nodes
 end
 
-local function hash_digest(hash_factory, message)
-  local hash = hash_factory:new()
-  if not hash then
-    return nil, "failed to create object"
-  end
-  local ok = hash:update(message)
-  if not ok then
-    return nil, "failed to add data"
-  end
-  local binary_digest = hash:final()
-  if binary_digest == nil then
-    return nil, "failed to create digest"
-  end
-  return resty_str.to_hex(binary_digest), nil
-end
-
-function _M.sha1_digest(message)
-  return hash_digest(resty_sha1, message)
-end
-
-function _M.md5_digest(message)
-  return hash_digest(resty_md5, message)
-end
-
 -- given an Nginx variable i.e $request_uri
 -- it returns value of ngx.var[request_uri]
 function _M.lua_ngx_var(ngx_var)