From e1e215467775c7475206711aaa48e5ab41a6c180 Mon Sep 17 00:00:00 2001
From: Yessiest <yessiest@memeware.net>
Date: Tue, 7 May 2024 19:07:34 +0400
Subject: [PATCH] Version bump and, finally, thread safety and shared request
 context memory

---
 examples/rack_app.ru           | 59 ++++++++++++++++------------------
 examples/thread_safety_test.ru | 39 ++++++++++++++++++++++
 examples/websockets.ru         | 40 +++++++++++------------
 landline.gemspec               |  2 +-
 lib/landline.rb                |  2 +-
 lib/landline/app.rb            | 41 +++++++++++++++--------
 lib/landline/path.rb           | 31 ++----------------
 lib/landline/probe.rb          | 22 -------------
 lib/landline/probe/handler.rb  | 12 +++++--
 lib/landline/request.rb        | 14 ++++++--
 lib/landline/sandbox.rb        | 32 ++++++++++++++++++
 lib/landline/server.rb         |  2 +-
 lib/landline/util/lookup.rb    |  2 ++
 13 files changed, 174 insertions(+), 124 deletions(-)
 create mode 100644 examples/thread_safety_test.ru
 create mode 100644 lib/landline/sandbox.rb

diff --git a/examples/rack_app.ru b/examples/rack_app.ru
index 4d502cf..cc8aaa3 100644
--- a/examples/rack_app.ru
+++ b/examples/rack_app.ru
@@ -19,31 +19,28 @@ end
 
 # Example Landline application as rack middleware
 class HelloServer < Landline::App
-  setup do
-    get "/test2" do
-      "Hello world from #{self}!"
-    end
-    handle do |status, backtrace: nil|
-      page = ([Landline::Util::HTTP_STATUS[status]] +
-              (backtrace || [""])).join("\n")
-      [
-        {
-          "content-length": page.bytesize,
-          "content-type": "text/plain",
-          "x-cascade": true
-        },
-        page
-      ]
-    end
+  get "/test2" do
+    "Hello world from #{self}!"
+  end
+
+  handle do |status, backtrace: nil|
+    page = ([Landline::Util::HTTP_STATUS[status]] +
+            (backtrace || [""])).join("\n")
+    [
+      {
+        "content-length": page.bytesize,
+        "content-type": "text/plain",
+        "x-cascade": true
+      },
+      page
+    ]
   end
 end
 
 # Example Landline app as rack application
 class CrossCallServer < Landline::App
-  setup do
-    get "/inner_test" do
-      "Hello world, through crosscall!"
-    end
+  get "/inner_test" do
+    "Hello world, through crosscall!"
   end
 end
 
@@ -52,21 +49,19 @@ class Server < Landline::App
   use TimerMiddleware
   use HelloServer
 
-  setup do
-    crosscall_server = CrossCallServer.new
+  crosscall_server = CrossCallServer.new
 
-    get "/test" do
-      "Hello from #{self}!"
-    end
+  get "/test" do
+    "Hello from #{self}!"
+  end
 
-    # Cross-callable application included as a subpath
-    link "/outer", crosscall_server
+  # Cross-callable application included as a subpath
+  link "/outer", crosscall_server
 
-    # Cross calling an application in a probe context
-    get "/crosscall" do
-      request.path = "/inner_test"
-      call(crosscall_server)
-    end
+  # Cross calling an application in a probe context
+  get "/crosscall" do
+    request.path = "/inner_test"
+    call(crosscall_server)
   end
 end
 
diff --git a/examples/thread_safety_test.ru b/examples/thread_safety_test.ru
new file mode 100644
index 0000000..14e1a84
--- /dev/null
+++ b/examples/thread_safety_test.ru
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require 'landline'
+
+class Application < Landline::App
+  def initialize(*args)
+    puts self
+    super(*args)
+  end
+
+  preprocess do
+    puts Thread.current.inspect
+  end
+
+  get "/long" do
+    before = request
+    sleep 10
+    "Request didn't change mid-execution: #{before == request}"
+  end
+
+  get "/long2" do
+    puts self
+    @instance_property = (rand * 1000).floor
+    response = "Your magic number is #{@instance_property}\n"
+    sleep 20
+    response += "Your magic number after waiting 20 seconds is #{@instance_property}"
+    response
+  end
+
+  get "/magic" do
+    @instance_property = (rand * 1000).floor
+  end
+
+  postprocess do
+    puts "Last value of instance_property: #{@instance_property}"
+  end
+end
+
+run Application.new
diff --git a/examples/websockets.ru b/examples/websockets.ru
index 012cd84..1475584 100644
--- a/examples/websockets.ru
+++ b/examples/websockets.ru
@@ -4,28 +4,26 @@ require 'landline'
 require 'landline/extensions/websocket'
 
 class Test < Landline::App
-  setup do
-    websocket "/test", version: 7 do |socket|
-      socket.on :message do |msg|
-        puts "Client wrote: #{msg}"
-      end
-      socket.on :error do |err|
-        puts "Error occured: #{err.inspect}"
-        puts err.backtrace
-      end
-      socket.on :close do
-        puts "Client closed read connection"
-      end
-      socket.ready
-      socket.write("Hi!")
-      response = socket.read
-      socket.write("You said: #{response}")
-      socket.write("Goodbye!")
-      socket.close
-    rescue Exception => e
-      puts e.inspect
-      puts e.backtrace
+  websocket "/test", version: 7 do |socket|
+    socket.on :message do |msg|
+      puts "Client wrote: #{msg}"
     end
+    socket.on :error do |err|
+      puts "Error occured: #{err.inspect}"
+      puts err.backtrace
+    end
+    socket.on :close do
+      puts "Client closed read connection"
+    end
+    socket.ready
+    socket.write("Hi!")
+    response = socket.read
+    socket.write("You said: #{response}")
+    socket.write("Goodbye!")
+    socket.close
+  rescue Exception => e
+    puts e.inspect
+    puts e.backtrace
   end
 end
 
diff --git a/landline.gemspec b/landline.gemspec
index c4eb1d4..3a28288 100644
--- a/landline.gemspec
+++ b/landline.gemspec
@@ -2,7 +2,7 @@
 
 Gem::Specification.new do |spec|
   spec.name                  = "landline"
-  spec.version               = "0.12.0"
+  spec.version               = "0.12.1"
   spec.summary               = "Elegant HTTP DSL"
   spec.description           = <<~DESC
     Landline is a no-hard-dependencies HTTP routing DSL that was made entirely for fun.
diff --git a/lib/landline.rb b/lib/landline.rb
index 8b55a36..72f564e 100644
--- a/lib/landline.rb
+++ b/lib/landline.rb
@@ -12,7 +12,7 @@ require_relative 'landline/app'
 # Landline is a backend framework born as a by-product of experimentation
 module Landline
   # Landline version
-  VERSION = '0.12 "Concrete and Gold" (pre-alpha)'
+  VERSION = '0.12.1 "Concrete and Gold" (pre-alpha)'
 
   # Landline branding and version
   VLINE = "Landline/#{Landline::VERSION} (Ruby/#{RUBY_VERSION}/#{RUBY_RELEASE_DATE})\n".freeze
diff --git a/lib/landline/app.rb b/lib/landline/app.rb
index 341e479..afbdf20 100644
--- a/lib/landline/app.rb
+++ b/lib/landline/app.rb
@@ -3,18 +3,20 @@
 module Landline
   # Rack application interface
   class App
-    # TODO: fix this mess somehow (probably impossible)
-
-    # @!parse include Landline::DSL::PathMethods
-    # @!parse include Landline::DSL::PathConstructors
-    # @!parse include Landline::DSL::ProbeConstructors
-    # @!parse include Landline::DSL::ProbeMethods
-    # @!parse include Landline::DSL::CommonMethods
     class << self
+      # TODO: fix this mess somehow (probably impossible)
+      # @!parse include Landline::DSL::PathMethods
+      # @!parse include Landline::DSL::PathConstructors
+      # @!parse include Landline::DSL::ProbeConstructors
+      # @!parse include Landline::DSL::ProbeMethods
+      # @!parse include Landline::DSL::CommonMethods
+
       # Duplicate used middleware for the subclassed app
       def inherited(subclass)
         super(subclass)
+        @setup_chain ||= []
         subclass.middleware = @middleware.dup
+        subclass.setup_chain = @setup_chain.dup
       end
 
       # Include a middleware in application
@@ -24,17 +26,30 @@ module Landline
         @middleware.append(middleware)
       end
 
-      # Setup block
-      # @param block [#call]
-      def setup(&block)
-        @setup_block = block
+      # Check if Server can respond to given symbol
+      def respond_to_missing?(symbol, _include_private)
+        Landline::ServerContext.instance_methods.include?(symbol) || super
       end
 
-      attr_accessor :middleware, :setup_block
+      # Store applied app manipulations
+      def method_missing(symbol, *args, **params, &callback)
+        if Landline::ServerContext.instance_methods.include? symbol
+          @setup_chain.append([symbol, args, params, callback])
+        else
+          super(symbol, *args, **params, &callback)
+        end
+      end
+
+      attr_accessor :middleware, :setup_chain
     end
 
     def initialize(*args, **opts)
-      @app = ::Landline::Server.new(*args, **opts, &self.class.setup_block)
+      setup_chain = self.class.setup_chain
+      @app = ::Landline::Server.new(*args, **opts) do
+        setup_chain.each do |symbol, cargs, cparams, callback|
+          send(symbol, *cargs, **cparams, &callback)
+        end
+      end
       self.class.middleware&.reverse_each do |cls|
         @app = cls.new(@app)
       end
diff --git a/lib/landline/path.rb b/lib/landline/path.rb
index 999e361..620ac2f 100644
--- a/lib/landline/path.rb
+++ b/lib/landline/path.rb
@@ -4,23 +4,9 @@ require_relative 'pattern_matching'
 require_relative 'node'
 require_relative 'dsl/constructors_path'
 require_relative 'dsl/methods_path'
-require_relative 'dsl/methods_common'
-require_relative 'dsl/methods_probe'
-require_relative 'dsl/constructors_probe'
 require_relative 'util/lookup'
 
 module Landline
-  # Execution context for filters and preprocessors.
-  class ProcessorContext
-    include Landline::DSL::CommonMethods
-    include Landline::DSL::ProbeMethods
-    include Landline::DSL::ProbeConstructors
-
-    def initialize(path)
-      @origin = path
-    end
-  end
-
   # Execution context for path setup block.
   class PathContext
     include Landline::DSL::PathConstructors
@@ -31,21 +17,8 @@ module Landline
     end
   end
 
-  # Ephemeral proxy class to which callback execution binds
-  class PathExecutionOrigin
-    def initialize(request, properties)
-      @request = request
-      @properties = Landline::Util::LookupROProxy.new(properties)
-    end
-
-    attr_accessor :response
-    attr_reader :request, :properties
-  end
-
   # Primary building block of request navigation.
   class Path < Landline::Node
-    ExecutionOrigin = Landline::PathExecutionOrigin
-    ProcContext = Landline::ProcessorContext
     Context = Landline::PathContext
 
     # @param path [Object] Object to generate {Landline::Pattern} from
@@ -108,8 +81,8 @@ module Landline
 
     # Create an execution context for in-path processing blocks
     def get_context(request)
-      exec_origin = self.class::ExecutionOrigin.new(request, @properties)
-      self.class::ProcContext.new(exec_origin)
+      request.context.origin.properties.lookup = @properties
+      request.context
     end
 
     # Sequentially run through all filters and drop request if one is false
diff --git a/lib/landline/probe.rb b/lib/landline/probe.rb
index a5e1db1..d19ddb6 100644
--- a/lib/landline/probe.rb
+++ b/lib/landline/probe.rb
@@ -24,28 +24,6 @@ module Landline
     autoload :Link, "landline/probe/crosscall_handler"
   end
 
-  # Context that provides execution context for Probes.
-  class ProbeContext
-    include Landline::DSL::ProbeConstructors
-    include Landline::DSL::ProbeMethods
-    include Landline::DSL::CommonMethods
-
-    def initialize(origin)
-      @origin = origin
-    end
-  end
-
-  # Ephemeral proxy class to which callback execution binds
-  class ProbeExecutionOrigin
-    def initialize(request, properties)
-      @request = request
-      @properties = Landline::Util::LookupROProxy.new(properties)
-    end
-
-    attr_accessor :response
-    attr_reader :request, :properties
-  end
-
   # Test probe. Also base for all "reactive" nodes.
   class Probe < Landline::Node
     # @param path [Object]
diff --git a/lib/landline/probe/handler.rb b/lib/landline/probe/handler.rb
index e090d85..eb92089 100644
--- a/lib/landline/probe/handler.rb
+++ b/lib/landline/probe/handler.rb
@@ -29,8 +29,8 @@ module Landline
       # @return [Boolean] true if further navigation is possible
       # @raise [UncaughtThrowError] may raise if die() is called.
       def process(request)
-        origin = Landline::ProbeExecutionOrigin.new(request, @properties)
-        context = Landline::ProbeContext.new(origin)
+        origin, context = get_context(request)
+
         return reject(request) unless request.path.match?(/^\/?$/)
 
         response = catch(:break) do
@@ -47,6 +47,14 @@ module Landline
         end
         throw :finish, response
       end
+
+      private
+
+      # Create a context to run handler in
+      def get_context(request)
+        request.context.origin.properties.lookup = @properties
+        [request.context.origin, request.context]
+      end
     end
   end
 end
diff --git a/lib/landline/request.rb b/lib/landline/request.rb
index e93155d..357d821 100644
--- a/lib/landline/request.rb
+++ b/lib/landline/request.rb
@@ -3,6 +3,7 @@
 require 'uri'
 require_relative 'util/query'
 require_relative 'util/cookie'
+require_relative 'sandbox'
 
 module Landline
   # Request wrapper for Rack protocol
@@ -30,13 +31,16 @@ module Landline
       @states = []
       # Postprocessors for current request
       @postprocessors = []
+      # Execution context
+      @context = init_context
     end
 
     # Run postprocessors
     # @param response [Landline::Response]
     def run_postprocessors(response)
+      @context.origin.properties.lookup = {}
       @postprocessors.reverse_each do |postproc|
-        postproc.call(self, response)
+        @context.instance_exec(self, response, &postproc)
       end
       @postprocessors = []
     end
@@ -90,11 +94,17 @@ module Landline
 
     attr_reader :request_method, :script_name, :path_info, :server_name,
                 :server_port, :server_protocol, :headers, :param, :splat,
-                :postprocessors, :cookies, :rack
+                :postprocessors, :cookies, :rack, :context
     attr_accessor :path, :filepath, :query
 
     private
 
+    # Initialize execution context
+    def init_context
+      origin = Landline::ProcessorOrigin.new(self, {})
+      Landline::ProcessorContext.new(origin)
+    end
+
     # Initialize basic rack request parameters
     # @param env [Hash]
     def init_request_params(env)
diff --git a/lib/landline/sandbox.rb b/lib/landline/sandbox.rb
new file mode 100644
index 0000000..39b1495
--- /dev/null
+++ b/lib/landline/sandbox.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require_relative 'dsl/methods_common'
+require_relative 'dsl/methods_probe'
+require_relative 'dsl/constructors_probe'
+require_relative 'util/lookup'
+
+module Landline
+  # Execution context for filters and preprocessors.
+  class ProcessorContext
+    include Landline::DSL::CommonMethods
+    include Landline::DSL::ProbeMethods
+    include Landline::DSL::ProbeConstructors
+
+    def initialize(path)
+      @origin = path
+    end
+
+    attr_reader :origin
+  end
+
+  # Ephemeral proxy class to which callback execution binds
+  class ProcessorOrigin
+    def initialize(request, properties)
+      @request = request
+      @properties = Landline::Util::LookupROProxy.new(properties)
+    end
+
+    attr_accessor :response
+    attr_reader :request, :properties
+  end
+end
diff --git a/lib/landline/server.rb b/lib/landline/server.rb
index 174e8c3..52b686e 100644
--- a/lib/landline/server.rb
+++ b/lib/landline/server.rb
@@ -14,7 +14,7 @@ module Landline
     # @param parent [Landline::Node, nil] Parent object to inherit properties to
     # @param setup [#call] Setup block
     def initialize(passthrough = nil, parent: nil, **opts, &setup)
-      super("", parent: nil, **opts, &setup)
+      super("", parent: parent, **opts, &setup)
       return if parent
 
       @passthrough = passthrough
diff --git a/lib/landline/util/lookup.rb b/lib/landline/util/lookup.rb
index d92f226..30b585a 100644
--- a/lib/landline/util/lookup.rb
+++ b/lib/landline/util/lookup.rb
@@ -46,6 +46,8 @@ module Landline
       def [](key)
         @lookup.[](key)
       end
+
+      attr_accessor :lookup
     end
   end
 end