You can find the Gist of movies references in this lesson here:
https://gist.github.com/tomgobich/2f29d392c67c9cc01dfa14e42f2995d5
Tapping into Model Factory States
In this lesson, we'll dive a little bit deeper into Model Factories by introducing factory states. We'll also learn how we can use the tap method to alter a factory result prior to it persisting into the database
- Author
- Tom Gobich
- Published
- Mar 15
- Duration
- 9m 15s
Developer, dog lover, and burrito eater. Currently teaching AdonisJS, a fully featured NodeJS framework, and running Adocasts where I post new lessons weekly. Professionally, I work with JavaScript, .Net C#, and SQL Server.
Adocasts
Burlington, KY
Transcript
Tapping into Model Factory States
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(upbeat music)
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So it'd be great if we actually had real movie titles
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inside of our application using faker information
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rather than just song names
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because now our application feels more like a song database
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rather than a movie database.
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So I've taken movies listed from the National Film Registry
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and I've normalized this into a JavaScript
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or TypeScript array of objects containing a title
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and a released year.
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So today we're gonna take this list
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and use it to seed our information
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inside of our application.
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So let's go ahead and hide our browser back away.
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Now we could use this list of titles
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directly inside of our Model Factory,
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but it would be great to also be able to generate out
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random movies that are future dated and the like
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since our list stops at 2017.
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So instead what we'll do is just use it
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directly inside of our fake seeder.
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It will just generate out one movie per record
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that we have inside of this list.
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Oops, I actually forgot to copy that list.
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So let's dive back into this gist that I have here,
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click on raw and let's Control or Command + A,
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Control or Command + C to give that a copy.
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Okay, now we can hide that back away.
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And inside of our database directory,
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let's go ahead and right click, new file,
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and let's create a folder.
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We could call this data, we could call this faker.
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I'm just gonna call this data for now, movies.ts.
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And let's go ahead and paste that list in
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and give it a save so that it formats.
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Cool, you see up here at line one,
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we're exporting const movies.
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So within our fake seeder, we can import that
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and let's make use of it inside of a separate method
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within here.
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So we'll call this async, we'll make it private
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and we'll call it create movies.
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Okay, now we still wanna make use of our Movie Factory.
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So we'll await movie factory.createMany
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and we'll wanna create one movie record per movie
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that we have inside of our data list here.
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So we wanna import our movies, so we'll type out movies
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and hit tab to auto import that from database data movies
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and provide it its array length.
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Now, currently this would create one movie
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with any random song name as its title.
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What we wanna do instead is tap into this
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prior to its actual creation.
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And with this tap method, we can provide a callback function
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that's provided a row, which in this case
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is going to be an instance of our movie model class.
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It'll also provide us a factory context
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and a factory builder.
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So within here, we can do row,
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provide that as a callback method
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and now if we type out row,
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we'll see that this looks exactly like a typical model would
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so we can type out title and overwrite the title
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prior to this record being persisted into the database
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because tap is run just before it is persistent.
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So within our tap callback method,
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what we wanna do is grab the index
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of the current movie that we're on.
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So let's do let index equals zero.
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We'll want to index plus plus at the end of this
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to increment that.
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We can go ahead and plop our movie into a variable.
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So we'll do const movie equals movies.index
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and then we can set the current movie title
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by calling movie.title.
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Now we can do something similar
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with the release data as well.
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Since we have the released year,
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so we can use faker by extracting that
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out of our factory context just like so.
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We can do faker.date.
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We can use the between method to start dates
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that the random date should be between.
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Since we only have the released year,
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we can set this to a random date within that year
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so that all of our movies aren't using the same month
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and day as we're looping over them here.
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So we'll say from and let's grab an instance
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of a LuxonDateTime object set to the movies released year.
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So we'll say released equals date time,
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importing that from Luxon just like so.
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So we'll say date time dot,
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and we can just set this to now
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and then overwrite the year to our movie.releasedYear.
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Cool, so now this object is set to a LuxonDateTime
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set to the current movies released year.
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So meaning we can do released.startOf
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to go to the start of the year
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and then to released.endOf
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to go to the end of the year.
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Now we have a couple of issues here to fix.
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Firstly, faker.date is going to return back
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an actual JavaScript date,
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whereas our released.dat is expecting a LuxonDateTime.
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So we can wrap this in dateTime from JS date
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to ingest the faker.date in as a LuxonDateTime.
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Give that a save.
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And now we have our second issue,
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which is that faker in the from and to
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is expecting a JavaScript date or a string or a number.
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So we have a couple of options there.
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We can either do toISO, toString, toFormat,
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or we can just do toJSDate
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to convert that to a JavaScript date.
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We'll just go ahead with that one, cool.
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So now as we loop through the movies that we're creating,
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one per record inside of our movie array here,
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we'll increment our index
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so that we can get an instance of the movie
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that we're currently on inside of our tap callback,
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overwrite the record's title with the actual movie title,
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and overwrite the released out with some random date
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between January 1st and December 31st
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of the current released year for that particular movie.
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Before we give this a go,
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let's go ahead and move our other movie factories,
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creation calls inside of our createMovies
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so that it's true to the method's name.
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So we'll go ahead and plop these down at the end
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after we run through our real movies, cool.
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We can also clean this particular movie factory
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up a little bit.
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So instead of merging in
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every time that we wanna create a movie that's released,
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we can instead specify a state directly on the movie factory
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and then just call that state here
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so that we don't need to merge the state in
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every single time.
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So within our movie factory, we can scroll down here,
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do .state, give the state a name.
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So we could do released.
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And then the second argument to this
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is going to be very similar to the tap method.
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It's going to provide us in the row for the movie
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prior to it being persisted into the database.
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And then we also get the factory context
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and factory builder as well.
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So we can extract faker out of this too.
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So we can do pretty much the exact same thing
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that we just did inside of our fake cedar
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to specify a movie has been released
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for whatever factory we're running this with.
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So we could do row.statusId to set that to
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movieStatuses.released,
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and then row.releasedAt equals dateTime.fromJSDate.
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We need to import that from Luxon.
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So dateTime, hit tab to auto import that from Luxon,
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just like so.
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And then we can use faker.date.
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And set this to sometime in the past
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since the movie will have been released.
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We can also do one for releasing soon.
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So if we give that a copy and a paste,
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we could do releasing soon,
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or just soon if you want to keep that nice and short.
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We can keep the movie status to released,
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and this will give the scope that we defined
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on our movie model a nice test case.
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So we can set the release date to soon
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rather than sometime in the past
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so that our movie status is set to released,
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but the release date is still sometime soon there
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in the future.
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So although the movie is set to released,
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it's not actually physically released
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because the release date has not been met yet.
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Let's do one more.
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So let's do one for post-production here.
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So we'll do state name of post-production,
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set the movie status to post-production,
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and we can leave the faker date to soon there.
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Okay, give that a save,
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jump into our faker cedar,
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and now we can replace this merge call here
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instead by applying one of our states.
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And for this, we just need to provide in the state name.
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So here we were creating released movies,
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so we'll call apply there with released as the argument,
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and now we're creating our released movies
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without having to merge in information for that.
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We can give that a copy,
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paste it two more times
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because we also have releasing soon
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as well as post-production that we can create as well.
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So we give that a save.
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Lastly, we need to actually call our create movie method.
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So up here within our run method,
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all we wanna do is await this create movies, just like so.
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Awesome.
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Now we're ready to go ahead and roll back our database,
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rerun everything and reseed our database as well.
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Now, one thing to note before we do that though,
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is that you don't wanna place this data directory
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inside of cedars because whenever we run our seed command,
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Athonis JS is going to try and auto import
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whatever cedar files we have within here,
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and if it's not an actual cedar,
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it's going to result in an error.
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So we've placed our data directory
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directly underneath database here
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for a very particular reason,
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even though we're only using it inside of our cedars.
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Okay, so let's go ahead and hide our text editor back away.
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Let's reset our database.
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So node ace migration reset.
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This is going to roll back
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all of the migrations that we have,
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regardless of what batch number it was run within.
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Okay, let's go ahead and node ace migration run
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to rerun those migrations.
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All right, and lastly, let's go ahead and node ace db seed.
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And we've run into an error.
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Now, here it's saying it cannot insert into users
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and specifically it's complaining
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about the user's role ID foreign key constraint.
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Essentially, we're trying to insert into users
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because our fake cedar is running prior to our start cedar.
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So our roles don't actually exist
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at the time that we're trying to insert
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into our user's database.
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So what we need to do is specify
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that we want the start cedar to run before our fake cedar,
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so that those roles and the information
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that we're creating inside of our start cedar
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actually exists whenever we get to our fake cedar.
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So let's go ahead and node ace migration reset
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to roll back all of our database migrations
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because our start cedar did succeed.
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So we wanna get rid of that information
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to test to make sure that our fix here works properly.
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Dive back in the Visual Studio Code.
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And by default, AdonisJS is going to run these
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similar to migrations.
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It's going to run them in alphabetical order
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or whatever order they're displayed in
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using a natural sort.
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And we want our fake cedar to run after our start cedar.
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So we'll just do 01 with an underscore there.
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And now we'll jump down to our start cedar.
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And we're always going to want this to run first.
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So we'll do 00.
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So now our start cedar is naturally sorted
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before our fake cedar.
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So AdonisJS should now run them
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in the order that we want them to.
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So we can hide our text editor back away.
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We've already reset our database.
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So let's go ahead and re-migrate it.
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So node is migration run.
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Cool, let's clear that out.
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And let's go ahead and seed our database once more.
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There we go, awesome.
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So it ran it in the order that we wanted it to
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and everything completed successfully.
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All right, let's go and run our server.
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So npm run dev, jump back into our browser,
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jump over to our application and look at that.
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Wow, we can keep scrolling and scrolling and scrolling
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and we're just gonna have a bunch of movies
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and even better yet, we now have actual movie titles.
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Some of these are gonna be song names,
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but for the most part, what we have here
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are actual movie titles that we're working with now.
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Awesome.
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So now we need to take care of the number
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that we're displaying,
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but we have plenty of movies to work with now
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at our disposal.
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Introduction
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Fundamentals
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2.0Routes and How To Create Them5m 23s
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2.1Rendering a View for a Route6m 29s
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2.2Linking Between Routes7m 51s
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2.3Loading A Movie Using Route Parameters9m 17s
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2.4Validating Route Parameters6m 6s
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2.5Vite and Our Assets6m 38s
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2.6Setting Up Tailwind CSS9m 5s
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2.7Reading and Supporting Markdown Content4m 32s
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2.8Listing Movies from their Markdown Files8m 51s
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2.9Extracting Reusable Code with Services7m 4s
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2.10Cleaning Up Routes with Controllers4m 52s
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2.11Defining A Structure for our Movie using Models9m 38s
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2.12Singleton Services and the Idea of Caching6m 11s
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2.13Environment Variables and their Validation4m 16s
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2.14Improved Caching with Redis10m 44s
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2.15Deleting Items and Flushing our Redis Cache6m 46s
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2.16Quick Start Apps with Custom Starter Kits6m 28s
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2.17Easy Imports with NodeJS Subpath Imports8m 40s
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Building Views with EdgeJS
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3.0EdgeJS Templating Basics8m 49s
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3.1HTML Attribute and Class Utilities6m 9s
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3.2Making A Reusable Movie Card Component10m 24s
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3.3Component Tags, State, and Props4m 53s
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3.4Use Slots To Make A Button Component6m 56s
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3.5Extracting A Layout Component5m 13s
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3.6State vs Share Data Flow2m 59s
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3.7Share vs Global Data Flow6m 7s
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3.8Form Basics and CSRF Protection6m 13s
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3.9HTTP Method Spoofing HTML Forms3m 3s
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3.10Easy SVG Icons with Edge Iconify7m 57s
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Database and Lucid ORM Basics
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4.0Configuring Lucid and our Database Connection4m 3s
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4.1Understanding our Database Schema9m 35s
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4.2Introducing and Defining Database Migrations18m 35s
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4.3The Flow of Migrations8m 28s
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4.4Introducing Lucid Models5m 43s
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4.5Defining Our Models6m 49s
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4.6The Basics of CRUD11m 56s
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4.7Defining Required Data with Seeders11m 11s
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4.8Stubbing Fake Data with Model Factories13m 48s
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4.9Querying Our Movies with the Query Builder15m 30s
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4.10Unmapped and Computed Model Properties3m 24s
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4.11Altering Tables with Migrations7m 6s
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4.12Adding A Profile Model, Migration, Factory, and Controller2m 57s
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4.13SQL Parameters and Injection Protection9m 19s
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4.14Reusable Query Statements with Model Query Scopes8m 11s
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4.15Tapping into Model Factory States9m 15s
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4.16Querying Recently Released and Coming Soon Movies4m 59s
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4.17Generating A Unique Movie Slug With Model Hooks7m 59s
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Lucid ORM Relationships
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5.0Defining One to One Relationships Within Lucid Models5m 49s
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5.1Model Factory Relationships2m 54s
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5.2Querying Relationships and Eager Vs Lazy Loading5m 17s
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5.3Cascading and Deleting Model Relationships5m 16s
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5.4Defining One to Many Relationships with Lucid Models6m 56s
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5.5Seeding Movies with One to Many Model Factory Relationships5m 24s
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5.6Listing A Director's Movies with Relationship Existence Queries8m 41s
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5.7Listing and Counting a Writer's Movies8m 41s
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5.8Using Eager and Lazy Loading to Load A Movie's Writer and Director5m 18s
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5.9Defining Many-To-Many Relationships and Pivot Columns9m 48s
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5.10Many-To-Many Model Factory Relationships4m 50s
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5.11A Deep Dive Into Relationship CRUD with Models18m 5s
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5.12How To Create Factory Relationships from a Pool of Data13m 55s
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5.13How To Query, Sort, and Filter by Pivot Table Data9m 47s
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Working With Forms
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6.0Accepting Form Data12m 15s
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6.1Validating Form Data with VineJS9m 29s
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6.2Displaying Validation Errors and Validating from our Request7m 16s
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6.3Reusing Old Form Values After A Validation Error2m 3s
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6.4Creating An EdgeJS Form Input Component5m 28s
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6.5Creating A Login Form and Validator5m 1s
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6.6How To Create A Custom VineJS Validation Rule9m 7s
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Authentication & Middleware
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The Flow of Middleware7m 49s
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Authenticating A Newly Registered User4m 14s
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Checking For and Populating an Authenticated User2m 10s
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Logging Out An Authenticated User2m 24s
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Logging In An Existing User6m 54s
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Remembering A User's Authenticated Session6m 55s
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Protecting Routes with Auth, Guest, and Admin Middleware5m 36s
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Filtering and Paginating Queries
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