{"action":"created","comment":{"url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/comments/41794245","id":41794245,"diff_hunk":"@@ -0,0 +1,113 @@\n+---\n+comments: true\n+date: 2015-10-15 14:00:00\n+layout: post\n+slug: shapeless-and-futures\n+title: Shapeless Futures\n+summary: In this post we will look into shapeless and use it to impove working with futures.\n+author: Tomasz Perek\n+feed_group: scala\n+tags:\n+- Scala\n+- Shapeless\n+- Futures\n+- Backend\n+- Type-level programming\n+---\n+\n+## <a href=\"#the-problem\" name=\"the-problem\">The problem</a>\n+Today, when reactive programming is so popular concept and you can see 'We're reactive!' claim on so many pages that have anything to do with scala (and not only), `Future`s are something you have to deal all the time. Things like getting records from the database, be it good old sql, mongo, or elasticsearch, dispatching http requests, communication between actors - are all handled in asynchronous way and you'll have to deal with `Future`s whether you want it or not. You probably will want to, because they are as a matter of fact extremely useful and convenient concept and simplify async programing a lot. You can easily wait on future completion, but as it's discouraged practice in most cases, you would rather chain it or do something else with it before it comes back to you with the result. Quite often you have to deal with many futures at once. In such cases for comprehension comes handy,and because scala's Future is actually a monad, you can do things like that:","path":"_posts/2015-10-15-shapeless-and-futures.md","position":19,"original_position":19,"commit_id":"f3987ab0e3e378d007437ab604f548a688ae2a5a","original_commit_id":"f3987ab0e3e378d007437ab604f548a688ae2a5a","user":{"login":"pjazdzewski1990","id":1136843,"avatar_url":"https://avatars.githubusercontent.com/u/1136843?v=3","gravatar_id":"","url":"https://api.github.com/users/pjazdzewski1990","html_url":"https://github.com/pjazdzewski1990","followers_url":"https://api.github.com/users/pjazdzewski1990/followers","following_url":"https://api.github.com/users/pjazdzewski1990/following{/other_user}","gists_url":"https://api.github.com/users/pjazdzewski1990/gists{/gist_id}","starred_url":"https://api.github.com/users/pjazdzewski1990/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/pjazdzewski1990/subscriptions","organizations_url":"https://api.github.com/users/pjazdzewski1990/orgs","repos_url":"https://api.github.com/users/pjazdzewski1990/repos","events_url":"https://api.github.com/users/pjazdzewski1990/events{/privacy}","received_events_url":"https://api.github.com/users/pjazdzewski1990/received_events","type":"User","site_admin":false},"body":"I would consider splitting the two first paragraphs into four smaller - large blocks of text don't do good for bounce rate. They are intimidating for most users","created_at":"2015-10-12T19:54:08Z","updated_at":"2015-10-12T19:54:08Z","html_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io/pull/81#discussion_r41794245","pull_request_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81","_links":{"self":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/comments/41794245"},"html":{"href":"https://github.com/ScalaConsultants/ScalaConsultants.github.io/pull/81#discussion_r41794245"},"pull_request":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81"}}},"pull_request":{"url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81","id":47343930,"html_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io/pull/81","diff_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io/pull/81.diff","patch_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io/pull/81.patch","issue_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/81","number":81,"state":"open","locked":false,"title":"shapeless and futures - first version","user":{"login":"tomaszperek","id":3693402,"avatar_url":"https://avatars.githubusercontent.com/u/3693402?v=3","gravatar_id":"","url":"https://api.github.com/users/tomaszperek","html_url":"https://github.com/tomaszperek","followers_url":"https://api.github.com/users/tomaszperek/followers","following_url":"https://api.github.com/users/tomaszperek/following{/other_user}","gists_url":"https://api.github.com/users/tomaszperek/gists{/gist_id}","starred_url":"https://api.github.com/users/tomaszperek/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/tomaszperek/subscriptions","organizations_url":"https://api.github.com/users/tomaszperek/orgs","repos_url":"https://api.github.com/users/tomaszperek/repos","events_url":"https://api.github.com/users/tomaszperek/events{/privacy}","received_events_url":"https://api.github.com/users/tomaszperek/received_events","type":"User","site_admin":false},"body":"","created_at":"2015-10-10T11:38:29Z","updated_at":"2015-10-12T19:54:08Z","closed_at":null,"merged_at":null,"merge_commit_sha":"f67ed2725378fc6eb1f9c4eb2927ee1848fd266e","assignee":null,"milestone":null,"commits_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81/commits","review_comments_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81/comments","review_comment_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/comments{/number}","comments_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/81/comments","statuses_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/statuses/f3987ab0e3e378d007437ab604f548a688ae2a5a","head":{"label":"ScalaConsultants:tperek-shapeless-futures","ref":"tperek-shapeless-futures","sha":"f3987ab0e3e378d007437ab604f548a688ae2a5a","user":{"login":"ScalaConsultants","id":6207831,"avatar_url":"https://avatars.githubusercontent.com/u/6207831?v=3","gravatar_id":"","url":"https://api.github.com/users/ScalaConsultants","html_url":"https://github.com/ScalaConsultants","followers_url":"https://api.github.com/users/ScalaConsultants/followers","following_url":"https://api.github.com/users/ScalaConsultants/following{/other_user}","gists_url":"https://api.github.com/users/ScalaConsultants/gists{/gist_id}","starred_url":"https://api.github.com/users/ScalaConsultants/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ScalaConsultants/subscriptions","organizations_url":"https://api.github.com/users/ScalaConsultants/orgs","repos_url":"https://api.github.com/users/ScalaConsultants/repos","events_url":"https://api.github.com/users/ScalaConsultants/events{/privacy}","received_events_url":"https://api.github.com/users/ScalaConsultants/received_events","type":"Organization","site_admin":false},"repo":{"id":15366666,"name":"ScalaConsultants.github.io","full_name":"ScalaConsultants/ScalaConsultants.github.io","owner":{"login":"ScalaConsultants","id":6207831,"avatar_url":"https://avatars.githubusercontent.com/u/6207831?v=3","gravatar_id":"","url":"https://api.github.com/users/ScalaConsultants","html_url":"https://github.com/ScalaConsultants","followers_url":"https://api.github.com/users/ScalaConsultants/followers","following_url":"https://api.github.com/users/ScalaConsultants/following{/other_user}","gists_url":"https://api.github.com/users/ScalaConsultants/gists{/gist_id}","starred_url":"https://api.github.com/users/ScalaConsultants/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ScalaConsultants/subscriptions","organizations_url":"https://api.github.com/users/ScalaConsultants/orgs","repos_url":"https://api.github.com/users/ScalaConsultants/repos","events_url":"https://api.github.com/users/ScalaConsultants/events{/privacy}","received_events_url":"https://api.github.com/users/ScalaConsultants/received_events","type":"Organization","site_admin":false},"private":false,"html_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io","description":"Scalac blog","fork":false,"url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io","forks_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/forks","keys_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/keys{/key_id}","collaborators_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/collaborators{/collaborator}","teams_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/teams","hooks_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/hooks","issue_events_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/events{/number}","events_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/events","assignees_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/assignees{/user}","branches_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/branches{/branch}","tags_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/tags","blobs_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/blobs{/sha}","git_tags_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/tags{/sha}","git_refs_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/refs{/sha}","trees_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/trees{/sha}","statuses_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/statuses/{sha}","languages_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/languages","stargazers_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/stargazers","contributors_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/contributors","subscribers_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/subscribers","subscription_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/subscription","commits_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/commits{/sha}","git_commits_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/commits{/sha}","comments_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/comments{/number}","issue_comment_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/comments{/number}","contents_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/contents/{+path}","compare_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/compare/{base}...{head}","merges_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/merges","archive_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/{archive_format}{/ref}","downloads_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/downloads","issues_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues{/number}","pulls_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls{/number}","milestones_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/milestones{/number}","notifications_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/notifications{?since,all,participating}","labels_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/labels{/name}","releases_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/releases{/id}","created_at":"2013-12-21T22:28:57Z","updated_at":"2015-10-12T13:00:18Z","pushed_at":"2015-10-12T13:11:34Z","git_url":"git://github.com/ScalaConsultants/ScalaConsultants.github.io.git","ssh_url":"git@github.com:ScalaConsultants/ScalaConsultants.github.io.git","clone_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io.git","svn_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io","homepage":null,"size":5252,"stargazers_count":2,"watchers_count":2,"language":"HTML","has_issues":true,"has_downloads":true,"has_wiki":true,"has_pages":true,"forks_count":9,"mirror_url":null,"open_issues_count":3,"forks":9,"open_issues":3,"watchers":2,"default_branch":"master"}},"base":{"label":"ScalaConsultants:master","ref":"master","sha":"4b637e6ec4f773bf602574bf125b3164f0c8617e","user":{"login":"ScalaConsultants","id":6207831,"avatar_url":"https://avatars.githubusercontent.com/u/6207831?v=3","gravatar_id":"","url":"https://api.github.com/users/ScalaConsultants","html_url":"https://github.com/ScalaConsultants","followers_url":"https://api.github.com/users/ScalaConsultants/followers","following_url":"https://api.github.com/users/ScalaConsultants/following{/other_user}","gists_url":"https://api.github.com/users/ScalaConsultants/gists{/gist_id}","starred_url":"https://api.github.com/users/ScalaConsultants/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ScalaConsultants/subscriptions","organizations_url":"https://api.github.com/users/ScalaConsultants/orgs","repos_url":"https://api.github.com/users/ScalaConsultants/repos","events_url":"https://api.github.com/users/ScalaConsultants/events{/privacy}","received_events_url":"https://api.github.com/users/ScalaConsultants/received_events","type":"Organization","site_admin":false},"repo":{"id":15366666,"name":"ScalaConsultants.github.io","full_name":"ScalaConsultants/ScalaConsultants.github.io","owner":{"login":"ScalaConsultants","id":6207831,"avatar_url":"https://avatars.githubusercontent.com/u/6207831?v=3","gravatar_id":"","url":"https://api.github.com/users/ScalaConsultants","html_url":"https://github.com/ScalaConsultants","followers_url":"https://api.github.com/users/ScalaConsultants/followers","following_url":"https://api.github.com/users/ScalaConsultants/following{/other_user}","gists_url":"https://api.github.com/users/ScalaConsultants/gists{/gist_id}","starred_url":"https://api.github.com/users/ScalaConsultants/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ScalaConsultants/subscriptions","organizations_url":"https://api.github.com/users/ScalaConsultants/orgs","repos_url":"https://api.github.com/users/ScalaConsultants/repos","events_url":"https://api.github.com/users/ScalaConsultants/events{/privacy}","received_events_url":"https://api.github.com/users/ScalaConsultants/received_events","type":"Organization","site_admin":false},"private":false,"html_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io","description":"Scalac blog","fork":false,"url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io","forks_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/forks","keys_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/keys{/key_id}","collaborators_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/collaborators{/collaborator}","teams_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/teams","hooks_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/hooks","issue_events_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/events{/number}","events_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/events","assignees_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/assignees{/user}","branches_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/branches{/branch}","tags_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/tags","blobs_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/blobs{/sha}","git_tags_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/tags{/sha}","git_refs_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/refs{/sha}","trees_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/trees{/sha}","statuses_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/statuses/{sha}","languages_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/languages","stargazers_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/stargazers","contributors_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/contributors","subscribers_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/subscribers","subscription_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/subscription","commits_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/commits{/sha}","git_commits_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/git/commits{/sha}","comments_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/comments{/number}","issue_comment_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/comments{/number}","contents_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/contents/{+path}","compare_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/compare/{base}...{head}","merges_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/merges","archive_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/{archive_format}{/ref}","downloads_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/downloads","issues_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues{/number}","pulls_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls{/number}","milestones_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/milestones{/number}","notifications_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/notifications{?since,all,participating}","labels_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/labels{/name}","releases_url":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/releases{/id}","created_at":"2013-12-21T22:28:57Z","updated_at":"2015-10-12T13:00:18Z","pushed_at":"2015-10-12T13:11:34Z","git_url":"git://github.com/ScalaConsultants/ScalaConsultants.github.io.git","ssh_url":"git@github.com:ScalaConsultants/ScalaConsultants.github.io.git","clone_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io.git","svn_url":"https://github.com/ScalaConsultants/ScalaConsultants.github.io","homepage":null,"size":5252,"stargazers_count":2,"watchers_count":2,"language":"HTML","has_issues":true,"has_downloads":true,"has_wiki":true,"has_pages":true,"forks_count":9,"mirror_url":null,"open_issues_count":3,"forks":9,"open_issues":3,"watchers":2,"default_branch":"master"}},"_links":{"self":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81"},"html":{"href":"https://github.com/ScalaConsultants/ScalaConsultants.github.io/pull/81"},"issue":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/81"},"comments":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/issues/81/comments"},"review_comments":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81/comments"},"review_comment":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/comments{/number}"},"commits":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/pulls/81/commits"},"statuses":{"href":"https://api.github.com/repos/ScalaConsultants/ScalaConsultants.github.io/statuses/f3987ab0e3e378d007437ab604f548a688ae2a5a"}}}}