--- title: Ruby on rails - how I get started slug: ruby-on-rails-how-i-get-started published_at: 2021-02-01 08:00:05 +0000 updated_at: 2026-03-04 20:14:31 +0000 summary: description: #rails #rubyonrails tags: [] views: 2440 author: CJ Avilla url: https://www.cjav.dev/videos/ruby-on-rails-how-i-get-started youtube_url: https://www.youtube.com/watch?v=LD49oT09jHs youtube_id: LD49oT09jHs embed_url: https://www.youtube.com/embed/LD49oT09jHs thumbnail_url: https://i.ytimg.com/vi/LD49oT09jHs/hqdefault.jpg type: video --- # Ruby on rails - how I get started *Published: February 01, 2021* *Views: 2440* ## Watch [Watch on YouTube](https://www.youtube.com/watch?v=LD49oT09jHs) [![Ruby on rails - how I get started](https://i.ytimg.com/vi/LD49oT09jHs/hqdefault.jpg)](https://www.youtube.com/watch?v=LD49oT09jHs) ## Description #rails #rubyonrails ## Transcript welcome dear viewer to uh the introduction to rails so i'm just going to quickly run through the way that i set up rails applications locally and some of the things that you might think about as you're getting started so the very first one is prerequisites so your computer must have a couple things installed applications that you're going to need installed one of them is ruby you can check if that is installed i've opened item 2 here that's the terminal application i use but if you're on a mac you can just type terminal and open that there are also instructions for windows but i don't uh i don't i'm not a user window user in this this guide is going to sort of assume that you're using mac um sorry but you should also be able to follow along as the commands are going to be the same but um yeah the the like sort of assumption is that we will be working from mac so we want to check that we have ruby installed you can do so by saying ruby-v this tells me that i have uh you know 2.6.3 ruby version 2.6.3 that's great um we're also going to need node so i'm going to say node v that'll tell me which node version i'm running by default if you use the default settings then when you set up a rails application the database that it uses is sqlite or sqlite3 so if you have sqlite um sqlite3 then you can just like run sqlite3 in the terminal and that will print out the version personally i prefer postgres um which you can download it's also another free open source database management system that you can download so check that out uh the latest versions of rails so as of this recording i think it's version six then you will also want yarn installed so you can say yarn and that's actually yar lizzy yarn dash v okay so the yarn v will tell you the version i've got 1.17.3 so that's how you check your dependencies now in order to install uh the command so rails typing rails that is a command that lets you run rail specific things that help you generate and scaffold and set up stuff so in order to have the rails command available you must first install the rails gem so you can say gem install rails and that will install the rails gem now depending on your system you may also need to update your environment path your path to um so so that when uh when you go to type a command uh you want to make sure that the rails command is available in at like any in any directory in your machine and the way that you do that is by setting up your path so if you type which rails this will tell you where the rails executable lives and so by saying which you can say which uh any any command and it'll tell you like where it's um where it's available like which brew right like homebrew is installed here rails is a ruby gem that is installed and i'm using arbenv as my ruby environment manager or my ruby version manager um so when i type which rails it tells me the path the full path to where the executable is this this like the stuff before rails here is in my um in my path i'm not going to export or i'm not going to print it out right now but those are some things that you'll need when you're getting started now in order to create a new rails application you say rails new and then the name of your app so in this example i'm going to say models demo and then there's a ton of different arguments that you can pass so you can specify which database you want to use and whether or not you want to use tests and whether or not you want to use this thing called turbo links whether or not you want to use the listen gem so by default you can just say rails new and that will fire up a very basic rails application i prefer to use postgres locally and also when i deploy i i prefer to deploy to heroku and so in future guides i'll likely walk through how to deploy your rails application to heroku heroku i don't know if it runs sql lite but it definitely runs postgres and there's a lot of really helpful things that you get from postgres like support for json and geo searching and there's just a bunch of reasons why postgres is incredible you should totally use it um i have postgres.app installed and so then you'll have like a little um elephant in the top bar which will tell you which version of postgres you have running so i'm running postgresql 12 and when i initialize this new rails application i want to pass dash database equals postgres ql um so it's not like postgres sql it's postgres and then ql at the end that's that's tripped me up before so uh generally i will also do dash t because by default rails is going to come with a testing framework called mini test by passing dash t i'm saying don't install the test framework because if i'm going to write tests which i do in any production application i don't want to write them in mini test i prefer to write them with rspec which is another testing library so here i would generally pass t to skip tests and those are the only options that i'm going to go over today so this takes a little while it goes through creates a bunch of files and folders and is scaffolding out all of the different gems and installing the dependencies in order to run a local version of rails so we here we see like a bunch of different gems here like we can go through them or you can go through them and kind of like dig through and read about what which what each of them do but this is like a gem for internationalization it looks like many tests did get installed active support there's this is a library of tons of helpful things that are added on top of the ruby language that are you know exposed as helper methods and things we've got bundler and e-ruby there's you know nokogiri is a very common gem for working with xml but also helpful for like parsing html and things they've you know we've got action view a set of tools for rendering your html views rack rack test there's just a ton of really helpful gems that come out of the box so it's also installing bootsnap and by bug as a debugger jbuilder is a thing for you know rendering json uh back to the client so really it is like a full batteries included uh web framework and that's one of the reasons why i really like working with it is uh it gives you just so much out of the box so after you've run that command rail's new we called our application here modelsdemo you can name it whatever you want i would i would recommend against naming it application that's like the one thing i wouldn't name it because that'll get really confusing and i've seen some really interesting errors when a rails app is named application okay so after you've done that i will create a new directory called the name of your app so now we can cd into models demo and we have now we have a full rails application right here and starting from the very beginning we can say rails server so again we're using the rails command and this time we're passing it a sub command server now this crashed and did not start up because it says webpacker configuration files not found no such file or folder please run rails webpacker install okay so it's telling us in the error message exactly how to fix it so we're going to run that rails webpacker colon install and then it says webpacker requires node greater than 10.17.0 and remember that when i said node v it was printing out 10.16 so i can now say which node and that will tell me where node is installed again it's similar to rbn for this one is node end and it tells me where node is installed and with node n i can actually say node n and that should allow me to see the list of commands i'm going to say node and versions to see the list of installed versions i have a few versions installed 10.16 is the default that's on my machine but i do have 10.17 so i can say noden local and that says set the local node version for this directory to and then i can pass in a version so i'll just say 10 17 0 as that was the the minimum required then i will rerun rails webpacker colon install and now that i have my local node end version set at the minimum version in order to to run webpacker this should work fine okay so this is installing some more dependencies similar to those gems that were installed now we're pulling down some javascript modules for sas and for handling a whole bunch of different things on the front end that come with rails out of the box so here's just a whole bunch of different uh node modules that are being installed okay all right that looks like it went fine all right let's try this rails server command again and okay so it says is booting puma puma is the name of the the web server that we're going to use that is like the ruby gem for actually serving the application you can configure it to use a number of different web servers puma is just one of several and down here we see that the this is the the version of puma that's running we see a whole bunch of information but the thing that's really cool is that now the server is listening on port 3000 on localhost so we can copy this and open it in the web browser and in the web browser we actually see right off the bat we see an error and it says active record error no database database models underscore demo underscore development does not exist that's because when we started the application we hadn't actually created the database which is required in order to run the application so i'm going to come back to the terminal and use control c to stop the server from running and i'm going to say rails db colon create previously this was rake db create rake is another tool for like writing some local tasks so now that we have run rails db create we can rerun rails server and any of these rails commands we can actually shorten to whatever the the shortest prefix that uniquely identifies the command is so we'll go back to the browser we're still at localhost 3000 refresh the page and yay you're on rails so now we have um a the foundation for a working rails application so that is uh that's how you get started and then in the next episode we'll talk about models --- [Back to all videos](https://www.cjav.dev/videos) --- ## Hey Agent, thanks for visiting! 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