Split out a nylas-streaming gem (#151)

This lays the foundation for a future `nylas-rails` gem while keeping
our build process and core dependencies lightweight.

We can now have `nylas` be the rest/http client while `nylas-streaming`
includes the event machine and yajl functionality so that users who
aren't using those don't pull in unnecessary dependencies or run into
dependency resolution conflicts.

* Inform users that delta streams are now part of nylas-streaming in the README
* Add post install message to ask people to read the upgrade guide

Gemfile

@@ -1,3 +1,3 @@
 source 'https://rubygems.org'
 
-gemspec
+gemspec name: 'nylas-streaming'

README.md

@@ -1,6 +1,6 @@
 # Nylas REST API Ruby bindings ![Travis build status](https://travis-ci.org/nylas/nylas-ruby.svg?branch=master)
 
-This README is for the Nylas Ruby SDK version 4. For those who are still using Nylas Ruby SDK Version 3, the documentation and source code is located in the [3.X-master branch](https://github.com/nylas/nylas-ruby/tree/3.X-master)
+This README is for the Nylas Ruby SDK version 4. For those who are still using Nylas Ruby SDK Version 3, the documentation and source code is located in the [3.X-master branch](https://github.com/nylas/nylas-ruby/tree/3.X-master). For those upgrading from 3.X to 4.0, review the [upgrade guide](https://github.com/nylas/nylas-ruby/wiki/Upgrading-from-3.X-to-4.0)
 
 ## Installation
 

gemfiles/Gemfile.rails4

@@ -2,4 +2,4 @@ source 'https://rubygems.org'
 
 gem 'rails', '~> 4.2'
 
-gemspec path: ".."
+gemspec path: '..', name: 'nylas-streaming'

gemfiles/Gemfile.rails4.lock

@@ -3,6 +3,10 @@ PATH
   specs:
     nylas (4.0.0.rc1)
       rest-client (>= 1.6)
+    nylas-streaming (4.0.0.rc1)
+      em-http-request (~> 1.1, >= 1.1.3)
+      nylas (>= 4.0)
+      yajl-ruby (~> 1.2, >= 1.2.1)
 
 GEM
   remote: https://rubygems.org/
@@ -220,9 +224,8 @@ PLATFORMS
 
 DEPENDENCIES
   bundler (>= 1.3.5)
-  em-http-request (~> 1.1, >= 1.1.3)
   jeweler (>= 2.1.2)
-  nylas!
+  nylas-streaming!
   pry (>= 0.10.4)
   pry-nav (>= 0.2.4)
   pry-stack_explorer (>= 0.4.9.2)
@@ -231,7 +234,6 @@ DEPENDENCIES
   shoulda (>= 3.4.0)
   sinatra (>= 1.4.7)
   webmock (>= 2.1.0)
-  yajl-ruby (~> 1.2, >= 1.2.1)
   yard (>= 0.9.12)
 
 BUNDLED WITH

gemfiles/Gemfile.rails5

@@ -2,4 +2,4 @@ source 'https://rubygems.org'
 
 gem 'rails', '~> 5'
 
-gemspec path: ".."
+gemspec path: "..", name: 'nylas-streaming'

gemfiles/Gemfile.rails5.lock

@@ -3,6 +3,10 @@ PATH
   specs:
     nylas (4.0.0.rc1)
       rest-client (>= 1.6)
+    nylas-streaming (4.0.0.rc1)
+      em-http-request (~> 1.1, >= 1.1.3)
+      nylas (>= 4.0)
+      yajl-ruby (~> 1.2, >= 1.2.1)
 
 GEM
   remote: https://rubygems.org/
@@ -228,9 +232,8 @@ PLATFORMS
 
 DEPENDENCIES
   bundler (>= 1.3.5)
-  em-http-request (~> 1.1, >= 1.1.3)
   jeweler (>= 2.1.2)
-  nylas!
+  nylas-streaming!
   pry (>= 0.10.4)
   pry-nav (>= 0.2.4)
   pry-stack_explorer (>= 0.4.9.2)
@@ -239,7 +242,6 @@ DEPENDENCIES
   shoulda (>= 3.4.0)
   sinatra (>= 1.4.7)
   webmock (>= 2.1.0)
-  yajl-ruby (~> 1.2, >= 1.2.1)
   yard (>= 0.9.12)
 
 BUNDLED WITH

gemfiles/Gemfile.rest-client.1

@@ -2,4 +2,4 @@ source 'https://rubygems.org'
 
 gem 'rest-client', '~> 1.6'
 
-gemspec path: ".."
+gemspec path: "..", name: 'nylas-streaming'

gemfiles/Gemfile.rest-client.1.lock

@@ -3,6 +3,10 @@ PATH
   specs:
     nylas (4.0.0.rc1)
       rest-client (>= 1.6)
+    nylas-streaming (4.0.0.rc1)
+      em-http-request (~> 1.1, >= 1.1.3)
+      nylas (>= 4.0)
+      yajl-ruby (~> 1.2, >= 1.2.1)
 
 GEM
   remote: https://rubygems.org/
@@ -148,9 +152,8 @@ PLATFORMS
 
 DEPENDENCIES
   bundler (>= 1.3.5)
-  em-http-request (~> 1.1, >= 1.1.3)
   jeweler (>= 2.1.2)
-  nylas!
+  nylas-streaming!
   pry (>= 0.10.4)
   pry-nav (>= 0.2.4)
   pry-stack_explorer (>= 0.4.9.2)
@@ -159,7 +162,6 @@ DEPENDENCIES
   shoulda (>= 3.4.0)
   sinatra (>= 1.4.7)
   webmock (>= 2.1.0)
-  yajl-ruby (~> 1.2, >= 1.2.1)
   yard (>= 0.9.12)
 
 BUNDLED WITH

gemfiles/Gemfile.rest-client.2

@@ -2,4 +2,4 @@ source 'https://rubygems.org'
 
 gem 'rest-client', '~> 2.0'
 
-gemspec path: ".."
+gemspec path: "..", name: 'nylas-streaming'

gemfiles/Gemfile.rest-client.2.lock

@@ -3,6 +3,10 @@ PATH
   specs:
     nylas (4.0.0.rc1)
       rest-client (>= 1.6)
+    nylas-streaming (4.0.0.rc1)
+      em-http-request (~> 1.1, >= 1.1.3)
+      nylas (>= 4.0)
+      yajl-ruby (~> 1.2, >= 1.2.1)
 
 GEM
   remote: https://rubygems.org/
@@ -148,9 +152,8 @@ PLATFORMS
 
 DEPENDENCIES
   bundler (>= 1.3.5)
-  em-http-request (~> 1.1, >= 1.1.3)
   jeweler (>= 2.1.2)
-  nylas!
+  nylas-streaming!
   pry (>= 0.10.4)
   pry-nav (>= 0.2.4)
   pry-stack_explorer (>= 0.4.9.2)
@@ -159,7 +162,6 @@ DEPENDENCIES
   shoulda (>= 3.4.0)
   sinatra (>= 1.4.7)
   webmock (>= 2.1.0)
-  yajl-ruby (~> 1.2, >= 1.2.1)
   yard (>= 0.9.12)
 
 BUNDLED WITH

lib/nylas-streaming.rb

@@ -0,0 +1,81 @@
+require 'yajl'
+require 'em-http'
+require 'nylas'
+
+module Nylas
+  class API
+    def delta_stream(cursor, exclude_types=[], timeout=0, expanded_view=false, include_types=[], &block)
+      Streaming::Stream.new(api: self, cursor: cursor, timeout: timeout, expanded_view: expanded_view,
+                            exclude_types: exclude_types, include_types: include_types).listen(&block)
+    end
+  end
+
+  module Streaming
+    class Stream
+      extend Forwardable
+      def_delegators :api, :url_for_path
+      attr_accessor :api, :timeout, :expanded_view, :include_types, :exclude_types, :cursor
+
+      def initialize(api: , cursor: , timeout: 0, expanded_view: false, include_types: [], exclude_types: [])
+        self.api = api
+        self.cursor = cursor
+        self.timeout = timeout
+        self.expanded_view = expanded_view
+        self.include_types = TypesFilter.new(:include, types: include_types)
+        self.exclude_types = TypesFilter.new(:exclude, types: exclude_types)
+      end
+
+      def listen
+        raise 'Please provide a block for receiving the delta objects' if !block_given?
+
+        exclude_string = exclude_types.to_query_string
+        include_string = include_types.to_query_string
+
+        # loop and yield deltas indefinitely.
+        path = self.url_for_path("/delta/streaming?exclude_folders=false&cursor=#{cursor}#{exclude_string}#{include_string}")
+        if expanded_view
+          path += '&view=expanded'
+        end
+
+        parser = Yajl::Parser.new(:symbolize_keys => false)
+        parser.on_parse_complete = proc do |data|
+          delta = Nylas.interpret_response(OpenStruct.new(:code => '200'), data, {:expected_class => Object, :result_parsed => true})
+
+          if not OBJECTS_TABLE.has_key?(delta['object'])
+            next
+          end
+
+          cls = OBJECTS_TABLE[delta['object']]
+          if EXPANDED_OBJECTS_TABLE.has_key?(delta['object']) and expanded_view
+            cls = EXPANDED_OBJECTS_TABLE[delta['object']]
+          end
+
+          obj = cls.new(api)
+
+          case delta["event"]
+          when 'create', 'modify'
+            obj.inflate(delta['attributes'])
+            obj.cursor = delta["cursor"]
+            yield delta["event"], obj
+          when 'delete'
+            obj.id = delta["id"]
+            obj.cursor = delta["cursor"]
+            yield delta["event"], obj
+          end
+        end
+
+        http = EventMachine::HttpRequest.new(path, :connect_timeout => 0, :inactivity_timeout => timeout).get(:keepalive => true)
+
+        # set a callback on the HTTP stream that parses incoming chunks as they come in
+        http.stream do |chunk|
+          parser << chunk
+        end
+
+        http.errback do
+          raise UnexpectedResponse.new http.error
+        end
+      end
+    end
+  end
+end
+

lib/nylas.rb

@@ -4,6 +4,8 @@
 require 'ostruct'
 require_relative 'nylas/to_query'
 
+require_relative 'nylas/types_filter'
+
 require 'nylas/account'
 require 'nylas/api_account'
 require 'nylas/thread'
@@ -23,6 +25,25 @@
 require 'nylas/version'
 
 module Nylas
+  OBJECTS_TABLE = {
+    "account" => Nylas::Account,
+    "calendar" => Nylas::Calendar,
+    "draft" => Nylas::Draft,
+    "thread" => Nylas::Thread,
+    "contact" => Nylas::Contact,
+    "event" => Nylas::Event,
+    "file" => Nylas::File,
+    "message" => Nylas::Message,
+    "folder" => Nylas::Folder,
+    "label" => Nylas::Label,
+  }
+
+  # It's possible to ask the API to expand objects.
+  # In this case, we do the right thing and return
+  # an expanded object.
+  EXPANDED_OBJECTS_TABLE = {
+    "message" => Nylas::ExpandedMessage,
+  }
   Error = Class.new(::StandardError)
   NoAuthToken = Class.new(Error)
   UnexpectedAccountAction = Class.new(Error)
@@ -265,46 +286,13 @@ def latest_cursor
       cursor
     end
 
-    OBJECTS_TABLE = {
-      "account" => Nylas::Account,
-      "calendar" => Nylas::Calendar,
-      "draft" => Nylas::Draft,
-      "thread" => Nylas::Thread,
-      "contact" => Nylas::Contact,
-      "event" => Nylas::Event,
-      "file" => Nylas::File,
-      "message" => Nylas::Message,
-      "folder" => Nylas::Folder,
-      "label" => Nylas::Label,
-    }
-
-    # It's possible to ask the API to expand objects.
-    # In this case, we do the right thing and return
-    # an expanded object.
-    EXPANDED_OBJECTS_TABLE = {
-      "message" => Nylas::ExpandedMessage,
-    }
-
-    def _build_types_filter_string(filter, types)
-      return "" if types.empty?
-      query_string = "&#{filter}_types="
-
-      types.each do |value|
-        count = 0
-        if OBJECTS_TABLE.has_value?(value)
-          param_name = OBJECTS_TABLE.key(value)
-          query_string += "#{param_name},"
-        end
-      end
 
-      query_string = query_string[0..-2]
-    end
 
     def deltas(cursor, exclude_types=[], expanded_view=false, include_types=[])
       return enum_for(:deltas, cursor, exclude_types, expanded_view, include_types) unless block_given?
 
-      exclude_string = _build_types_filter_string(:exclude, exclude_types)
-      include_string = _build_types_filter_string(:include, include_types)
+      exclude_string = TypesFilter.new(:exclude, types: exclude_types).to_query_string
+      include_string = TypesFilter.new(:include, types: include_types).to_query_string
 
       # loop and yield deltas until we've come to the end.
       loop do
@@ -351,6 +339,10 @@ def deltas(cursor, exclude_types=[], expanded_view=false, include_types=[])
       end
     end
 
-    require 'nylas/api/delta_stream'
+    def delta_stream(cursor, exclude_types=[], timeout=0, expanded_view=false, include_types=[], &block)
+      raise NotImplementedError, "the `#delta_stream` method was removed in 4.0 in favor of using the " \
+                                 "`nylas-streming` gem. This reduces the dependency footprint of the core " \
+                                 "nylas gem for those not using the streaming API."
+    end
   end
 end