feat: implement @cached route decorator

Author: Ethosa

src/happyx/private/macro_utils.nim

@@ -60,6 +60,26 @@ proc isIdentUsed*(body, name: NimNode): bool =
   false
 
 
+proc findAllUses*(body, name: NimNode, uses: var seq[NimNode]) =
+  ## Рекурсивно ищет все использования идентификатора `name` в дереве AST `body`.
+  for statement in body:
+    if body.kind in {nnkIdentDefs, nnkExprEqExpr, nnkExprColonExpr} and statement == body[0]:
+      continue
+    if body.kind == nnkDotExpr and statement == body[1] and statement != body[0]:
+      continue
+    if statement == name:
+      uses.add(body)  # Добавляем узел, где найдено использование
+    elif statement.kind notin AtomicNodes:
+      findAllUses(statement, name, uses)
+
+
+proc getIdentUses*(body, name: NimNode): seq[NimNode] =
+  ## Возвращает все использования идентификатора `name` в дереве AST `body`.
+  var uses: seq[NimNode] = @[]
+  findAllUses(body, name, uses)
+  return uses
+
+
 proc newCast*(fromType, toType: NimNode): NimNode =
   newNimNode(nnkCast).add(toType, fromType)
 

src/happyx/routing/decorators.nim

@@ -35,15 +35,31 @@ import
   std/macros,
   std/tables,
   std/strformat,
+  std/strutils,
   std/base64,
-  ../core/constants
+  std/httpcore,
+  ../core/constants,
+  ../private/macro_utils,
+  ./routing
 
 
 export base64
 
 
 type
-  DecoratorImpl* = proc(httpMethods: seq[string], routePath: string, statementList: NimNode, arguments: seq[NimNode])
+  DecoratorImpl* = proc(
+    httpMethods: seq[string],
+    routePath: string,
+    statementList: NimNode,
+    arguments: seq[NimNode]
+  )
+  CachedResult* = object
+    data*: string
+    headers*: HttpHeaders
+    statusCode*: HttpCode
+  CachedRoute* = object
+    create_at*: float
+    res*: CachedResult
 
 
 var decorators* {.compileTime.} = newTable[string, DecoratorImpl]()
@@ -74,6 +90,9 @@ macro decorator*(name, body: untyped): untyped =
 
 
 when enableDefaultDecorators:
+  var cachedRoutes* {.threadvar.}: Table[string, CachedRoute]
+  cachedRoutes = initTable[string, CachedRoute]()
+
   proc authBasicDecoratorImpl(httpMethods: seq[string], routePath: string, statementList: NimNode, arguments: seq[NimNode]) =
     statementList.insert(0, parseStmt"""
 var (username, password) = ("", "")
@@ -123,8 +142,87 @@ var userAgent = navigator.userAgent
     )
 
 
+  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:
+        arguments[0]
+      else:
+        newLit(60)
+    
+    var routeKey = fmt"{purePath}:pp("
+    for i in route.pathParams:
+      routeKey &= i.name & "={" & i.name & "}"
+    routeKey &= ")"
+    echo routeKey
+
+    let
+      queryStmt = newStmtList()
+      queryArrStmt = newStmtList()
+
+    if statementList.isIdentUsed(ident"query"):
+      var usages = statementList.getIdentUses(ident"query")
+      for i in usages:
+        if i.kind == nnkInfix and i[0] == ident"?" and i[1] == ident"query" and i[2].kind == nnkIdent:
+          queryStmt.add parseStmt(fmt"""routeKey &= "{i[2]}" & "=" & query.getOrDefault("{i[2]}", "")""")
+        elif i.kind == nnkBracketExpr and i[0] == ident"query" and i[1].kind == nnkStrLit:
+          queryStmt.add parseStmt(fmt"""routeKey &= "{i[1].strVal}" & "=" & query.getOrDefault("{i[1].strVal}", "")""")
+        elif i.kind == nnkBracketExpr and i[0] == ident"query":
+          queryStmt.add parseStmt(fmt"""routeKey &= {i[1].toStrLit} & "=" & query.getOrDefault({i[1].toStrLit}, "")""")
+        else:
+          discard
+          # echo i.treeRepr
+    if statementList.isIdentUsed(ident"queryArr"):
+      var usages = statementList.getIdentUses(ident"queryArr")
+      for i in usages:
+        if i.kind == nnkInfix and i[0] == ident"?" and i[1] == ident"queryArr" and i[2].kind == nnkIdent:
+          queryStmt.add parseStmt(fmt"""routeKey &= "{i[2]}" & "=" & $queryArr.getOrDefault("{i[2]}", "")""")
+        elif i.kind == nnkBracketExpr and i[0] == ident"queryArr" and i[1].kind == nnkStrLit:
+          queryStmt.add parseStmt(fmt"""routeKey &= "{i[1].strVal}" & "=" & $queryArr.getOrDefault("{i[1].strVal}", "")""")
+        elif i.kind == nnkBracketExpr and i[0] == ident"queryArr":
+          queryStmt.add parseStmt(fmt"""routeKey &= {i[1].toStrLit} & "=" & $queryArr.getOrDefault({i[1].toStrLit}, "")""")
+        else:
+          discard
+          # echo i.treeRepr
+
+    let cachedRoutesResult = newNimNode(nnkDotExpr).add(
+      newNimNode(nnkBracketExpr).add(ident"cachedRoutes", ident"routeKey"), ident"res"
+    )
+    let cachedRoutesCreateAt = newNimNode(nnkDotExpr).add(
+      newNimNode(nnkBracketExpr).add(ident"cachedRoutes", ident"routeKey"), ident"create_at"
+    )
+
+    statementList.insert(0, newStmtList(
+      newVarStmt(ident"routeKey", newCall("fmt", newLit(fmt"{routeKey}"))),
+      queryStmt,
+      queryArrStmt,
+      newConstStmt(ident"thisRouteCanBeCached", newLit(true)),
+      newNimNode(nnkIfStmt).add(newNimNode(nnkElifBranch).add(
+        newCall("hasKey", ident"cachedRoutes", ident"routeKey"),
+        newNimNode(nnkIfStmt).add(newNimNode(nnkElifBranch).add(
+          newCall("<", newCall("-", newCall("cpuTime"), cachedRoutesCreateAt), expiresIn),
+          newStmtList(
+            newConstStmt(ident"thisIsCachedResponse", newLit(true)),
+            newCall(
+              "answer",
+              ident"req",
+              newNimNode(nnkDotExpr).add(cachedRoutesResult, ident"data"),
+              newNimNode(nnkDotExpr).add(cachedRoutesResult, ident"statusCode"),
+              newNimNode(nnkDotExpr).add(cachedRoutesResult, ident"headers"),
+            ),
+            newNimNode(nnkBreakStmt).add(ident"__handleRequestBlock")
+          )
+        )),
+      )),
+    ))
+
+
   static:
     regDecorator("AuthBasic", authBasicDecoratorImpl)
     regDecorator("AuthBearerJWT", authBearerJwtDecoratorImpl)
     regDecorator("AuthJWT", authJwtDecoratorImpl)
     regDecorator("GetUserAgent", getUserAgentDecoratorImpl)
+    regDecorator("Cached", cachedDecoratorImpl)

src/happyx/ssr/core.nim

@@ -45,7 +45,7 @@ else:
   import std/posix
   import std/osproc
 
-export httpcore
+export httpcore, times
 
 
 func parseHttpMethod*(data: string): Option[HttpMethod] =

src/happyx/ssr/server.nim

@@ -286,6 +286,22 @@ template answer*(
   when declared(outHeaders):
     for key, val in outHeaders.pairs():
       h[key] = val
+  
+  # Cache result
+  when declared(thisRouteCanBeCached) and declared(routeKey) and not declared(thisIsCachedResponse):
+    cachedRoutes[routeKey] = CachedRoute(create_at: cpuTime())
+    when message is string:
+      cachedRoutes[routeKey].res = CachedResult(data: message)
+    else:
+      cachedRoutes[routeKey].res = CachedResult(data: $message)
+    cachedRoutes[routeKey].res.statusCode = code
+    when useHeaders:
+      cachedRoutes[routeKey].res.headers = h
+    else:
+      cachedRoutes[routeKey].res.headers = newHttpHeaders([
+        ("Content-Type", "text/plain;charset=utf-8")
+      ])
+
   # HTTPX
   when enableHttpx or enableBuiltin:
     when useHeaders:
@@ -395,6 +411,17 @@ template answer*(
   when declared(outHeaders):
     for key, val in outHeaders.pairs():
       h[key] = val
+  
+  # Cache result
+  when declared(thisRouteCanBeCached) and declared(routeKey) and not declared(thisIsCachedResponse):
+    cachedRoutes[routeKey] = CachedRoute(create_at: cpuTime())
+    when message is string:
+      cachedRoutes[routeKey].res = CachedResult(data: message)
+    else:
+      cachedRoutes[routeKey].res = CachedResult(data: $message)
+    cachedRoutes[routeKey].res.statusCode = code
+    cachedRoutes[routeKey].res.headers = h
+  
   # HTTPX
   when enableHttpx or enableBuiltin:
     var headersArr = ""

tests/testc16.nim

@@ -1,4 +1,5 @@
 import
+  std/asyncdispatch,
   ../src/happyx,
   jwt
 
@@ -102,6 +103,23 @@ serve "127.0.0.1", 5000:
   put "/post/$id:int":
     ## Edits a post
     return "Hello, world!"
+  
+  @Cached  # Expires in 60 seconds by default
+  get "/cached/{i:int}":
+    await sleepAsync(1000)
+    if true:
+      if (query?test) == "hello":
+        return 100
+    echo query?one
+    return i
+  
+  @Cached(120)  # Expires in 60 seconds by default
+  get "/cached/{x}":
+    await sleepAsync(1000)
+    if query.hasKey("key"):
+      return query["key"]
+    await sleepAsync(1000)
+    return x
 
   @AuthBasic
   post "/test/basic-auth":