feat(plugins/proxy-cache): add wildcard and parameter match support f…

…or content_type

CHANGELOG.md

@@ -80,6 +80,8 @@
   as little as possible. During that time, the invalid sessions could cause failures and partial downtime.
   All existing sessions are invalidated when upgrading to this version.
   [#10199](https://github.com/Kong/kong/pull/10199)
+- **Proxy Cache**: Add wildcard and parameter match support for content_type
+  [#10209](https://github.com/Kong/kong/pull/10209)
 
 ### Additions
 

kong/plugins/proxy-cache/handler.lua

@@ -1,7 +1,9 @@
 local require     = require
 local cache_key   = require "kong.plugins.proxy-cache.cache_key"
 local utils       = require "kong.tools.utils"
-local kong_meta = require "kong.meta"
+local kong_meta   = require "kong.meta"
+local mime_type   = require "kong.tools.mime_type"
+local nkeys       = require "table.nkeys"
 
 
 local ngx              = ngx
@@ -20,6 +22,7 @@ local ngx_re_gmatch    = ngx.re.gmatch
 local ngx_re_sub       = ngx.re.gsub
 local ngx_re_match     = ngx.re.match
 local parse_http_time  = ngx.parse_http_time
+local parse_mime_type  = mime_type.parse_mime_type
 
 
 local tab_new = require("table.new")
@@ -173,11 +176,27 @@ local function cacheable_response(conf, cc)
       return false
     end
 
+    local t, subtype, params = parse_mime_type(content_type)
     local content_match = false
     for i = 1, #conf.content_type do
-      if conf.content_type[i] == content_type then
-        content_match = true
-        break
+      local expected_ct = conf.content_type[i]
+      local exp_type, exp_subtype, exp_params = parse_mime_type(expected_ct)
+      if exp_type then
+        if (exp_type == "*" or t == exp_type) and
+          (exp_subtype == "*" or subtype == exp_subtype) then
+          local params_match = true
+          for key, value in pairs(exp_params or EMPTY) do
+            if value ~= (params or EMPTY)[key] then
+              params_match = false
+              break
+            end
+          end
+          if params_match and
+            (nkeys(params or EMPTY) == nkeys(exp_params or EMPTY)) then
+            content_match = true
+            break
+          end
+        end
       end
     end
 

spec/03-plugins/31-proxy-cache/01-schema_spec.lua

@@ -121,4 +121,32 @@ describe("proxy-cache schema", function()
     assert.is_nil(err)
     assert.is_truthy(entity)
   end)
+
+  it("accepts wildcard content_type", function()
+    local entity, err = v({
+      strategy = "memory",
+      content_type = { "application/*", "*/text" },
+    }, proxy_cache_schema)
+
+    assert.is_nil(err)
+    assert.is_truthy(entity)
+
+    local entity, err = v({
+      strategy = "memory",
+      content_type = { "*/*" },
+    }, proxy_cache_schema)
+
+    assert.is_nil(err)
+    assert.is_truthy(entity)
+  end)
+
+  it("accepts content_type with parameter", function()
+    local entity, err = v({
+      strategy = "memory",
+      content_type = { "application/json; charset=UTF-8" },
+    }, proxy_cache_schema)
+
+    assert.is_nil(err)
+    assert.is_truthy(entity)
+  end)
 end)

spec/03-plugins/31-proxy-cache/02-access_spec.lua

@@ -77,6 +77,16 @@ do
       local route16 = assert(bp.routes:insert({
         hosts = { "route-16.com" },
       }))
+      local route17 = assert(bp.routes:insert({
+        hosts = { "route-17.com" },
+      }))
+      local route18 = assert(bp.routes:insert({
+        hosts = { "route-18.com" },
+      }))
+      local route19 = assert(bp.routes:insert({
+        hosts = { "route-19.com" },
+      }))
+
 
       local consumer1 = assert(bp.consumers:insert {
         username = "bob",
@@ -242,6 +252,36 @@ do
         },
       })
 
+      assert(bp.plugins:insert {
+        name = "proxy-cache",
+        route = { id = route17.id },
+        config = {
+          strategy = policy,
+          [policy] = policy_config,
+          content_type = { "*/*" },
+        },
+      })
+
+      assert(bp.plugins:insert {
+        name = "proxy-cache",
+        route = { id = route18.id },
+        config = {
+          strategy = policy,
+          [policy] = policy_config,
+          content_type = { "application/xml; charset=UTF-8" },
+        },
+      })
+
+      assert(bp.plugins:insert {
+        name = "proxy-cache",
+        route = { id = route19.id },
+        config = {
+          strategy = policy,
+          [policy] = policy_config,
+          content_type = { "application/xml;" }, -- invalid content_type
+        },
+      })
+
       assert(helpers.start_kong({
         plugins = "bundled",
         nginx_conf = "spec/fixtures/custom_nginx.template",
@@ -1240,5 +1280,71 @@ do
         assert.matches("^%d+$", res.headers["X-Kong-Upstream-Latency"])
       end)
     end)
+
+    describe("content-type", function()
+      it("should cache a request with wildcard content_type(*/*)", function()
+        local request = {
+          method = "GET",
+          path = "/xml",
+          headers = {
+            host = "route-17.com",
+          },
+        }
+
+        local res = assert(client:send(request))
+        assert.res_status(200, res)
+        assert.same("application/xml", res.headers["Content-Type"])
+        assert.same("Miss", res.headers["X-Cache-Status"])
+
+        local res = assert(client:send(request))
+        assert.res_status(200, res)
+        assert.same("application/xml", res.headers["Content-Type"])
+        assert.same("Hit", res.headers["X-Cache-Status"])
+      end)
+
+      it("should not cache a request while parameter is not match", function()
+        local res = assert(client:send {
+          method = "GET",
+          path = "/xml",
+          headers = {
+            host = "route-18.com",
+          },
+        })
+
+        assert.res_status(200, res)
+        assert.same("application/xml", res.headers["Content-Type"])
+        assert.same("Bypass", res.headers["X-Cache-Status"])
+      end)
+
+
+      it("should not cause error while upstream returns a invalid content type", function()
+        local res = assert(client:send {
+          method = "GET",
+          path = "/response-headers?Content-Type=application/xml;",
+          headers = {
+            host = "route-18.com",
+          },
+        })
+
+        assert.res_status(200, res)
+        assert.same("application/xml;", res.headers["Content-Type"])
+        assert.same("Bypass", res.headers["X-Cache-Status"])
+      end)
+
+      it("should not cause error while config.content_type has invalid element", function()
+        local res, err = client:send {
+          method = "GET",
+          path = "/xml",
+          headers = {
+            host = "route-19.com",
+          },
+        }
+
+        assert.is_nil(err)
+        assert.res_status(200, res)
+        assert.same("application/xml", res.headers["Content-Type"])
+        assert.same("Bypass", res.headers["X-Cache-Status"])
+      end)
+    end)
   end)
 end