fix(client) ensure validTtl override does not interfere with TTL of

README.md

@@ -50,7 +50,12 @@ Release process:
 4. commit and tag the release
 5. upload rock to LuaRocks
 
-### 6.0.1 (22-Jun-2021) 
+### 6.0.x (unreleased)
+
+- Fix: `validTtl` should not be used for host-file entries.
+  [PR 134](https://github.com/Kong/lua-resty-dns-client/pull/134)
+
+### 6.0.1 (22-Jun-2021)
 
 - Performance: reduce amount of timers on init_worker. [PR 130](https://github.com/Kong/lua-resty-dns-client/pull/130)
 

spec/client_cache_spec.lua

@@ -551,4 +551,31 @@ describe("[DNS client cache]", function()
 
   end)
 
+
+  describe("hosts entries", function()
+    -- hosts file names are cached for 10 years, verify that
+    -- it is not overwritten with validTtl settings.
+    -- Regressions reported in https://github.com/Kong/kong/issues/7444
+    local lrucache, mock_records, config  -- luacheck: ignore
+    before_each(function()
+      config = {
+        nameservers = { "8.8.8.8" },
+        hosts = {"127.0.0.1 myname.lan"},
+        resolvConf = {},
+        validTtl = 0.1,
+        staleTtl = 0,
+      }
+
+      assert(client.init(config))
+      lrucache = client.getcache()
+    end)
+
+    it("entries from hosts file ignores validTtl overrides, Kong/kong #7444", function()
+      ngx.sleep(0.2) -- must be > validTtl + staleTtl
+
+      record = client.getcache():get("1:myname.lan")
+      assert.equal("127.0.0.1", record[1].address)
+    end)
+  end)
+
 end)

src/resty/dns/client.lua

@@ -460,9 +460,6 @@ _M.init = function(options)
   staleTtl = options.staleTtl or 4
   log(DEBUG, PREFIX, "staleTtl = ", staleTtl)
 
-  validTtl = options.validTtl
-  log(DEBUG, PREFIX, "validTtl = ", tostring(validTtl))
-
   cacheSize = options.cacheSize or 10000  -- default set here to be able to reset the cache
   noSynchronisation = options.noSynchronisation
   log(DEBUG, PREFIX, "noSynchronisation = ", tostring(noSynchronisation))
@@ -543,6 +540,12 @@ _M.init = function(options)
     end
   end
 
+  -- see: https://github.com/Kong/kong/issues/7444
+  -- since the validTtl affects ttl of caching entries,
+  -- only set it after hosts entries are inserted
+  -- so that the 10 years of TTL for hosts file actually takes effect.
+  validTtl = options.validTtl
+  log(DEBUG, PREFIX, "validTtl = ", tostring(validTtl))
 
   -- Deal with the `resolv.conf` file