fix: invalidate cache in core.request.add_haeder and fix some calls

apisix/core/request.lua

@@ -108,16 +108,13 @@ function _M.header(ctx, name)
     return _headers(ctx)[name]
 end
 
-
-function _M.set_header(ctx, header_name, header_value)
+local function modify_header(ctx, header_name, header_value, update_func, override)
     if type(ctx) == "string" then
         -- It would be simpler to keep compatibility if we put 'ctx'
         -- after 'header_value', but the style is too ugly!
         header_value = header_name
         header_name = ctx
         ctx = nil
-
-        log.warn("DEPRECATED: use set_header(ctx, header_name, header_value) instead")
     end
 
     local err
@@ -131,26 +128,36 @@ function _M.set_header(ctx, header_name, header_value)
         changed = a6_request.is_request_header_set()
     end
 
-    ngx.req.set_header(header_name, header_value)
+    update_func(header_name, header_value)
 
     if is_apisix_or and not changed then
         -- if the headers are not changed before,
         -- we can only update part of the cache instead of invalidating the whole
         a6_request.clear_request_header()
         if ctx and ctx.headers then
-            ctx.headers[header_name] = header_value
+            if override or not ctx.headers[header_name] then
+                ctx.headers[header_name] = header_value
+            else
+                ctx.headers[header_name] = ctx.headers[header_name] .. header_value
+            end
         end
     end
 end
 
-function _M.add_header(header_name, header_value)
-    local err
-    header_name, err = _validate_header_name(header_name)
-    if err then
-        error(err)
+function _M.set_header(ctx, header_name, header_value)
+    if type(ctx) == "string" then
+        log.warn("DEPRECATED: use set_header(ctx, header_name, header_value) instead")
+    end
+
+    modify_header(ctx, header_name, header_value, ngx.req.set_header, true)
+end
+
+function _M.add_header(ctx, header_name, header_value)
+    if type(ctx) == "string" then
+        log.warn("DEPRECATED: use add_header(ctx, header_name, header_value) instead")
     end
 
-    req_add_header(header_name, header_value)
+    modify_header(ctx, header_name, header_value, req_add_header, false)
 end
 
 -- return the remote address of client which directly connecting to APISIX.

apisix/plugins/proxy-rewrite.lua

@@ -311,18 +311,18 @@ do
         for i = 1, field_cnt, 2 do
             local val = core.utils.resolve_var(hdr_op.add[i + 1], ctx.var)
             local header = hdr_op.add[i]
-            core.request.add_header(header, val)
+            core.request.add_header(ctx, header, val)
         end
 
         local field_cnt = #hdr_op.set
         for i = 1, field_cnt, 2 do
             local val = core.utils.resolve_var(hdr_op.set[i + 1], ctx.var)
-            core.request.set_header(hdr_op.set[i], val)
+            core.request.set_header(ctx, hdr_op.set[i], val)
         end
 
         local field_cnt = #hdr_op.remove
         for i = 1, field_cnt do
-            core.request.set_header(hdr_op.remove[i], nil)
+            core.request.set_header(ctx, hdr_op.remove[i], nil)
         end
 
     end

t/core/request.t

@@ -439,3 +439,43 @@ while ($i <= 101) {
 $s
 --- response_body
 101
+
+
+
+=== TEST 15: add header
+--- config
+    location /t {
+        content_by_lua_block {
+            local core = require("apisix.core")
+            ngx.ctx.api_ctx = {}
+            local ctx = ngx.ctx.api_ctx
+            core.request.add_header(ctx, "test_header", "test")
+            local h = core.request.header(ctx, "test_header")
+            ngx.say(h)
+            core.request.add_header(ctx, "test_header", "t2")
+            local h2 = core.request.header(ctx, "test_header")
+            ngx.say(h2)
+        }
+    }
+--- response_body
+test
+testt2
+
+
+
+=== TEST 16: call add_header with deprecated way
+--- config
+    location /t {
+        content_by_lua_block {
+            local core = require("apisix.core")
+            ngx.ctx.api_ctx = {}
+            local ctx = ngx.ctx.api_ctx
+            core.request.add_header("test_header", "test")
+            local h = core.request.header(ctx, "test_header")
+            ngx.say(h)
+        }
+    }
+--- response_body
+test
+--- error_log
+DEPRECATED: use add_header(ctx, header_name, header_value) instead

t/plugin/proxy-rewrite3.t

@@ -455,3 +455,12 @@ passed
 GET /echo HTTP/1.1
 --- response_headers
 test: test_in_set
+
+
+
+=== TEST 21: deprecated calls test
+--- request
+GET /echo HTTP/1.1
+--- no_error_log
+DEPRECATED: use add_header(ctx, header_name, header_value) instead
+DEPRECATED: use set_header(ctx, header_name, header_value) instead