feat(decorators): add rate limit decorator

examples/website/src/docs/decorators.nim

@@ -40,6 +40,10 @@ proc Decorators*(): TagRef =
 
       CodeBlock("nim", nimCachedDecorator, "cached_decorator")
 
+      tP: { translate"Besides caching and authorization, HappyX also has a RateLimit decorator:" }
+
+      CodeBlock("nim", nimRateLimitDecorator, "rate_limit_decorator")
+
       tH2: { translate"Custom Decorators 💡"}
       tP: { translate"You can create your own decorators also:" }
 

examples/website/src/ui/code/nim_ssr.nim

@@ -698,4 +698,12 @@ serve ... :
   post "/cached/[m:TestModel]":
     await sleepAsync(1000)
     return m.username
+"""
+  nimRateLimitDecorator* = """serve ... :
+  # default values is perSecond=60, fromAll=false
+  @RateLimit(perSecond = 2, fromAll = true)
+  get "/test/rate-limit":
+    outHeaders["Test"] = 10
+    outHeaders["HappyXHeader"] = "Hello"
+    return "Hello, world!"
 """

examples/website/src/ui/translations.nim

@@ -2720,6 +2720,12 @@ translatable:
     "zh" -> "请输入点什么"
     "fr" -> "Entrez quelque chose"
     "ko" -> "무언가를 입력하세요"
+  "Besides caching and authorization, HappyX also has a RateLimit decorator:":
+    "ru" -> "Помимо кэширования и авторизации HappyX имеет также декоратор RateLimit:"
+    "ja" -> "キャッシングや認証に加えて、HappyXにはRateLimitデコレーターもあります："
+    "zh" -> "除了缓存和授权，HappyX还具有RateLimit装饰器："
+    "fr" -> "En plus de la mise en cache et de l'autorisation, HappyX dispose également d'un décorateur RateLimit :"
+    "ko" -> "캐싱 및 인증 외에도 HappyX에는 RateLimit 데코레이터가 있습니다:"
 
 
 var spokenLang: cstring

happyx.nimble

@@ -2,7 +2,7 @@
 
 description = "Macro-oriented asynchronous web-framework written with ♥"
 author = "HapticX"
-version = "4.7.0"
+version = "4.7.1"
 license = "MIT"
 srcDir = "src"
 installExt = @["nim"]

src/happyx/core/constants.nim

@@ -110,7 +110,7 @@ const
   # Framework version
   HpxMajor* = 4
   HpxMinor* = 7
-  HpxPatch* = 0
+  HpxPatch* = 1
   HpxVersion* = $HpxMajor & "." & $HpxMinor & "." & $HpxPatch
 
 

src/happyx/routing/decorators.nim

@@ -60,6 +60,9 @@ type
   CachedRoute* = object
     create_at*: float
     res*: CachedResult
+  RateLimitInfo* = object
+    amount*: int
+    update_at*: float
 
 
 var decorators* {.compileTime.} = newTable[string, DecoratorImpl]()
@@ -93,6 +96,9 @@ when enableDefaultDecorators:
   var cachedRoutes* {.threadvar.}: Table[string, CachedRoute]
   cachedRoutes = initTable[string, CachedRoute]()
 
+  var rateLimits* {.threadvar.}: Table[string, RateLimitInfo]
+  rateLimits = initTable[string, RateLimitInfo]()
+
   proc authBasicDecoratorImpl(httpMethods: seq[string], routePath: string, statementList: NimNode, arguments: seq[NimNode]) =
     statementList.insert(0, parseStmt"""
 var (username, password) = ("", "")
@@ -142,16 +148,58 @@ var userAgent = navigator.userAgent
     )
 
 
+  proc rateLimitDecoratorImpl(httpMethods: seq[string], routePath: string, statementList: NimNode, arguments: seq[NimNode]) =
+    var
+      fromAll = true
+      perSecond = 60
+
+    const intLits = { nnkIntLit..nnkInt64Lit }
+    let boolean = [newLit(true), newLit(false)]
+
+    for argument in arguments:
+      if argument.kind == nnkExprEqExpr and argument[0] == ident"fromAll" and argument[1] in boolean:
+        fromAll = argument[1].boolVal
+      elif argument.kind == nnkExprEqExpr and argument[0] == ident"perSecond" and argument[1].kind in intLits:
+        perSecond = argument[1].intVal.int
+
+    statementList.insert(0, parseStmt(fmt"""
+let key =
+  when {not fromAll}:
+    if hostname != "":
+      hostname & "{routePath}"
+    elif headers.hasKey("X-Forwarded-For"):
+      headers["X-Forwarded-For"].split(",", 1)[0] & "{routePath}"
+    elif headers.hasKey("X-Real-Ip"):
+      headers["X-Real-Ip"] & "{routePath}"
+    else:
+      "{routePath}"
+  else:
+    "{routePath}"
+if not rateLimits.hasKey(key):
+  rateLimits[key] = RateLimitInfo(amount: 1, update_at: cpuTime())
+elif cpuTime() - rateLimits[key].update_at < 1.0:
+  inc rateLimits[key].amount
+else:
+  rateLimits[key].update_at = cpuTime()
+  rateLimits[key].amount = 1
+
+if rateLimits[key].amount > {perSecond}:
+  var statusCode = 429
+  return "Too many requests"
+""")
+    )
+
+
   proc cachedDecoratorImpl(httpMethods: seq[string], routePath: string, statementList: NimNode, arguments: seq[NimNode]) =
     let
       route = handleRoute(routePath)
       purePath = route.purePath.replace('{', '_').replace('}', '_')
 
     let expiresIn =
-      if arguments.len == 1 and arguments[0].kind in {nnkIntLit, nnkInt16Lit, nnkInt32Lit, nnkInt64Lit, nnkInt8Lit}:
+      if arguments.len == 1 and arguments[0].kind in { nnkIntLit..nnkInt64Lit }:
         newLit(arguments[0].intVal.int)
       elif arguments.len == 1 and arguments[0].kind == nnkExprEqExpr and arguments[0][0] == ident"expires":
-        if arguments[0][1].kind in {nnkIntLit, nnkInt16Lit, nnkInt32Lit, nnkInt64Lit, nnkInt8Lit}:
+        if arguments[0][1].kind in { nnkIntLit..nnkInt64Lit }:
           newLit(arguments[0][1].intVal.int)
         else:
           newLit(60)
@@ -239,3 +287,4 @@ var userAgent = navigator.userAgent
     regDecorator("AuthJWT", authJwtDecoratorImpl)
     regDecorator("GetUserAgent", getUserAgentDecoratorImpl)
     regDecorator("Cached", cachedDecoratorImpl)
+    regDecorator("RateLimit", rateLimitDecoratorImpl)

tests/testc16.nim

@@ -95,6 +95,13 @@ serve "127.0.0.1", 5000:
     outHeaders["Test"] = 10
     outHeaders["HappyXHeader"] = "Hello"
     return "Hello, world!"
+
+  # default values is perSecond=60, fromAll=false
+  @RateLimit(perSecond = 2, fromAll = true)
+  get "/test/rate-limit":
+    outHeaders["Test"] = 10
+    outHeaders["HappyXHeader"] = "Hello"
+    return "Hello, world!"
 
   post "/post":
     ## Creates a new post