Add Kemal::Context.get? to safely access context storage. Fixes #428

spec/context_spec.cr

@@ -1,71 +1,107 @@
 require "./spec_helper"
 
 describe "Context" do
-  it "sets content type" do
-    get "/" do |env|
-      env.response.content_type = "application/json"
-      "Hello"
+  context "headers" do
+    it "sets content type" do
+      get "/" do |env|
+        env.response.content_type = "application/json"
+        "Hello"
+      end
+      request = HTTP::Request.new("GET", "/")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("application/json")
+    end
+
+    it "parses headers" do
+      get "/" do |env|
+        name = env.request.headers["name"]
+        "Hello #{name}"
+      end
+      headers = HTTP::Headers.new
+      headers["name"] = "kemal"
+      request = HTTP::Request.new("GET", "/", headers)
+      client_response = call_request_on_app(request)
+      client_response.body.should eq "Hello kemal"
+    end
+
+    it "sets response headers" do
+      get "/" do |env|
+        env.response.headers.add "Accept-Language", "tr"
+      end
+      request = HTTP::Request.new("GET", "/")
+      client_response = call_request_on_app(request)
+      client_response.headers["Accept-Language"].should eq "tr"
     end
-    request = HTTP::Request.new("GET", "/")
-    client_response = call_request_on_app(request)
-    client_response.headers["Content-Type"].should eq("application/json")
   end
 
-  it "parses headers" do
-    get "/" do |env|
-      name = env.request.headers["name"]
-      "Hello #{name}"
-    end
-    headers = HTTP::Headers.new
-    headers["name"] = "kemal"
-    request = HTTP::Request.new("GET", "/", headers)
-    client_response = call_request_on_app(request)
-    client_response.body.should eq "Hello kemal"
-  end
+  context "storage" do
+    it "can store primitive types" do
+      before_get "/" do |env|
+        env.set "before_get", "Kemal"
+        env.set "before_get_int", 123
+        env.set "before_get_float", 3.5
+      end
 
-  it "sets response headers" do
-    get "/" do |env|
-      env.response.headers.add "Accept-Language", "tr"
-    end
-    request = HTTP::Request.new("GET", "/")
-    client_response = call_request_on_app(request)
-    client_response.headers["Accept-Language"].should eq "tr"
-  end
+      get "/" do |env|
+        {
+          before_get:              env.get("before_get"),
+          before_get_int:          env.get("before_get_int"),
+          before_get_float:        env.get("before_get_float")
+        }
+      end
 
-  it "can store variables" do
-    before_get "/" do |env|
-      t = TestContextStorageType.new
-      t.id = 32
-      a = AnotherContextStorageType.new
-      env.set "key", "value"
-      env.set "before_get", "Kemal"
-      env.set "before_get_int", 123
-      env.set "before_get_context_test", t
-      env.set "another_context_test", a
-      env.set "before_get_float", 3.5
+      request = HTTP::Request.new("GET", "/")
+      io = IO::Memory.new
+      response = HTTP::Server::Response.new(io)
+      context = HTTP::Server::Context.new(request, response)
+      Kemal::FilterHandler::INSTANCE.call(context)
+      Kemal::RouteHandler::INSTANCE.call(context)
+
+      context.get("before_get").should eq "Kemal"
+      context.get("before_get_int").should eq 123
+      context.get("before_get_float").should eq 3.5
     end
 
-    get "/" do |env|
-      env.set "key", "value"
-      {
-        key:                     env.get("key"),
-        before_get:              env.get("before_get"),
-        before_get_int:          env.get("before_get_int"),
-        before_get_float:        env.get("before_get_float"),
-        before_get_context_test: env.get("before_get_context_test"),
-      }
+    it "can store custom types" do
+      before_get "/" do |env|
+        t = TestContextStorageType.new
+        t.id = 32
+        a = AnotherContextStorageType.new
+
+        env.set "before_get_context_test", t
+        env.set "another_context_test", a
+      end
+
+      get "/" do |env|
+        {
+          before_get_context_test: env.get("before_get_context_test"),
+          another_context_test: env.get("another_context_test"),
+        }
+      end
+
+      request = HTTP::Request.new("GET", "/")
+      io = IO::Memory.new
+      response = HTTP::Server::Response.new(io)
+      context = HTTP::Server::Context.new(request, response)
+      Kemal::FilterHandler::INSTANCE.call(context)
+      Kemal::RouteHandler::INSTANCE.call(context)
+
+      context.get("before_get_context_test").as(TestContextStorageType).id.should eq 32
+      context.get("another_context_test").as(AnotherContextStorageType).name.should eq "kemal-context"
     end
 
-    request = HTTP::Request.new("GET", "/")
-    io = IO::Memory.new
-    response = HTTP::Server::Response.new(io)
-    context = HTTP::Server::Context.new(request, response)
-    Kemal::FilterHandler::INSTANCE.call(context)
-    Kemal::RouteHandler::INSTANCE.call(context)
-    context.store["key"].should eq "value"
-    context.store["before_get"].should eq "Kemal"
-    context.store["before_get_int"].should eq 123
-    context.store["before_get_float"].should eq 3.5
-    context.store["before_get_context_test"].as(TestContextStorageType).id.should eq 32
+    it "fetches non-existent keys from store with get?" do
+      get "/" {}
+
+      request = HTTP::Request.new("GET", "/")
+      io = IO::Memory.new
+      response = HTTP::Server::Response.new(io)
+      context = HTTP::Server::Context.new(request, response)
+      Kemal::FilterHandler::INSTANCE.call(context)
+      Kemal::RouteHandler::INSTANCE.call(context)
+
+      context.get?("non_existent_key").should eq nil
+      context.get?("another_non_existent_key").should eq nil
+    end
   end
 end

src/kemal/ext/context.cr

@@ -10,7 +10,7 @@ class HTTP::Server
 
     macro finished
       alias StoreTypes = Union({{ *STORE_MAPPINGS }})
-      getter store = {} of String => StoreTypes
+      @store = {} of String => StoreTypes
     end
 
     def params
@@ -58,5 +58,9 @@ class HTTP::Server
     def set(name : String, value : StoreTypes)
       @store[name] = value
     end
+
+    def get?(name : String)
+      @store[name]?
+    end
   end
 end