00:00:01Commons greater learning greater
00:00:03opportunities greater life visit us at
00:00:07Greater Commons comm so I want to show
00:00:10you how to do a basic web app using the
00:00:12go programming language and I’m just
00:00:14going to introduce you to the resources
00:00:15and give you all the code that you need
00:00:17and get you up and running and you’ll be
00:00:20able to do create read update delete and
00:00:22you’ll be able to use Postgres to do it
00:00:25and and it will all be with the go
00:00:27programming language but I want you to
00:00:30like this video and I want you to
00:00:33retweet this video and I want you to
00:00:35share it on social networks because here
00:00:38on YouTube these are the videos in my
00:00:40channel and in this video here build web
00:00:45apps go language 135,000 people have
00:00:48watched it and that’s an OK video but I
00:00:51made that like a year ago and so I
00:00:53really need this video here to be what
00:00:56people are watching because this video
00:00:58and the material I have to share with
00:01:00you is way way better and I’ve been
00:01:03teaching go and web dev would go at the
00:01:06University and the college level for a
00:01:08couple years now and I’ve worked with
00:01:10Caleb doxy and Bill Kennedy right just
00:01:13to get the go code perfect and here’s
00:01:17the code base you know the resource
00:01:20here’s here’s the code pathway for
00:01:23learning go web dev and this is the best
00:01:26code pathway in the entire world
00:01:28and I know because this is what I do
00:01:30full time I study go I study go web dev
00:01:34and I teach it at the college of the
00:01:36University and I’ve worked with you know
00:01:38Caleb dachsie like created the
00:01:41foundation of this code base and we’ve
00:01:43built upon it so it’s an amazing code
00:01:45base it’s the best code base in the
00:01:47entire world screaming web dev let’s go
00:01:49so just discovering this like just tweet
00:01:52this video so people can discover this
00:01:53because I want people to get into the
00:01:57gogo language I love it and I want to I
00:02:00want to spread the gospel of go and and
00:02:03so people have a good way to learn it
00:02:05and get into it they’ll be more likely
00:02:08to use it I’m not paid by Google either
00:02:11by the way
00:02:12so down here is Postgres we’re going to
00:02:15like do this post grass and look at this
00:02:17code that’s when we’re going to look at
00:02:19but in post grass and you can go install
00:02:21post grass and Postgres website alright
00:02:26I’ve lost my voice I just got to talk
00:02:29quiet I guess but down here you hit
00:02:32download and if you’re on a Mac you just
00:02:35want to get this one right here that’s
00:02:36light and that’s easy and if you’re on a
00:02:38Windows you could you can watch my
00:02:41training where I show you how to do all
00:02:43this my training you can find it for
00:02:46migrator comments comm look there first
00:02:48we’re building a site all and go and
00:02:51it’s a place where you’ll be able to
00:02:53teach and and and you know deliver
00:02:55educational content very economically to
00:02:58help people learn for the greater good
00:03:00of humanity greater Commons so if it’s
00:03:03not if it hasn’t launched yet the course
00:03:05will be up there when this launches
00:03:06right now you can also find the course
00:03:08on Todd MacLeod view to me so just go
00:03:11google that and you’ll get to the course
00:03:13go web dev and that shows you how to do
00:03:16it on Windows Postgres and everything
00:03:18all right so let’s see it so you get
00:03:22Postgres installed and then you want to
00:03:24create a database a book store so you
00:03:27can see there i have a database
00:03:28bookstore that’s right there that’s my
00:03:30database if we go go into in the
00:03:33bookstore and then take a look at you
00:03:36know it’s got one table books so we can
00:03:38select everything from books right and
00:03:41there what did I mess up select star
00:03:44from books select let’s just try it
00:03:48again
00:03:49sometimes my terminal does that see same
00:03:51command and in there out so there are my
00:03:54three records I got three records in
00:03:56there let’s look at the code and yeah
00:04:00it’s working on us on a map Mac I just
00:04:02wander if I to pull it but here here we
00:04:04have the code and this is the exact same
00:04:06code which is right here right exact
00:04:10same code it’s probably I can note but
00:04:14I’m in that so you have access to this
00:04:15code did I already show you the URL
00:04:17there’s the URL
00:04:20so you go into this code and then here
00:04:23all the steps to build it up and this is
00:04:26like you know an hour to of training
00:04:29right there so I’m not going to go
00:04:30through all of it but this is the
00:04:32finished deal let’s just watch it run
00:04:34and then I’ll show you the code walk you
00:04:36through the code so I’m going to switch
00:04:38into that over here on this side I’m
00:04:40already there yeah I’m in 44:22 so I’m
00:04:46going to run that and we’ll come over
00:04:50and take a look at it and so yeah there
00:04:54are those three records we saw and I
00:04:56could insert a book but I don’t want to
00:04:59have to think of an ISBN number and so I
00:05:05don’t know what’s the title of a book
00:05:08West with night a Beryl Markham if you
00:05:15have not read this book I will not be
00:05:19steering you wrong go get this book this
00:05:23book is like one of the best books I’ve
00:05:25ever read in my life it’s so great I
00:05:28created that book showed the record go
00:05:31back to all books it’s in there I can
00:05:33update it if I want
00:05:35that’s like I’m a blues singer or some
00:05:39so change numbers out of the West with
00:05:42the night Beryl Markham let’s say we’re
00:05:44making it on sale so now it’s 1499 go
00:05:49back to all books and Emma Jane Austen
00:05:52who wanted to read that delete that we
00:05:55got crud created read update delete and
00:06:02it’s all restful right we go look at a
00:06:05book books show nice URLs drop the drop
00:06:10to you know some value in there URL
00:06:12parameters so look at that code right
00:06:15here you know I could go into this in
00:06:21quite a bit of depth so I was the first
00:06:24place to start if you don’t know any go
00:06:26web dev it’s a really it’s a kind of an
00:06:30entire process so I
00:06:32think I’m just going to keep this video
00:06:34short because this would be about 40
00:06:37minutes for me to walk you through all
00:06:38this but I think that this is the best
00:06:45example this code for learning how to do
00:06:50go web dev I kind of want to go into it
00:06:54I kind of feel you say man go into it
00:06:57let’s go into it so if you don’t if if
00:07:05this doesn’t make sense to you I’ve got
00:07:07an introduction to the go programming
00:07:08language and I’m just giving me the
00:07:10resources and I’m not trying to sell you
00:07:12something I mean obviously this is also
00:07:14how help support my family got two kids
00:07:17and but if you don’t have the resources
00:07:22the money the course is usually like ten
00:07:23or fifteen dollars if you don’t have the
00:07:26money to pay for that just send me an
00:07:27email on Twitter message me on Twitter
00:07:31and here’s my Twitter deal and at Todd
00:07:37McCloud I guess the shade URL that’s
00:07:38better send me a message on Twitter and
00:07:41just interesting god I totally want to
00:07:44take course but I’m college to it in our
00:07:46live in India or you know I don’t have
00:07:49that money whatever I don’t care what
00:07:50your reason is you don’t have the money
00:07:52that’s fine I’ll give you free access I
00:07:55want you to learn it for the good of all
00:07:56for the greater good the greater cons
00:07:58that’s why we’re building that site so
00:08:02just send me a message and I’ll give you
00:08:03free access but I have an introduction
00:08:05of a go programming language to teach
00:08:07you everything all right so really go
00:08:11look at the net HTTP package so if this
00:08:14doesn’t make sense
00:08:15take that introduction course and here
00:08:17in the net HT package we have type
00:08:19Handler and type handler is an interface
00:08:22okay so an interface allows polymorphism
00:08:26and go so I click on that and I see type
00:08:29handler and anything that has this
00:08:31method implicitly implements the handler
00:08:34interface and that means that if I have
00:08:36some type and it has a method and that
00:08:39method has this signature and that a
00:08:42value of that type also is of a handler
00:08:45type
00:08:45and and so that’s how the interfaces
00:08:50work and again go watch the introduction
00:08:52training it doesn’t make sense because
00:08:53I’m going to try to keep this a little
00:08:54brief you got a little bit of like a
00:08:58hangnail I’m not totally weird all right
00:09:02so that’s the handler interface and
00:09:04serve HTTP response writer an employer
00:09:08to request my joke which I tell on class
00:09:11is what is a interface say says hey baby
00:09:14if you’ve got these methods then you’re
00:09:17my type so the handler interface and the
00:09:22reason the handler interface is the
00:09:24entry point for understanding the net
00:09:27HTTP package is because if you look up
00:09:29here handlers are used all over you see
00:09:32them in the index of all the different
00:09:34functions and things it’s like it’s used
00:09:37all over handler and their handler and
00:09:40particularly here right if we look for
00:09:43listening served there’s listen and
00:09:45serve and it takes an address in the
00:09:48handler and so that handler right here
00:09:52that we pass in right that’s going to be
00:09:54our server or serve MUX at the false or
00:09:56MUX or MUX whatever you want to call it
00:09:58and so if we pass in nil as I was
00:10:02passing in so let’s just go down here
00:10:04and look at it and we’ll search for nil
00:10:15so there’s no and if you pass a nil you
00:10:19use the default serve MUX okay so the
00:10:22default serve MUX well with the default
00:10:25serve MUX we can use handle and handle
00:10:36func handle and handle fog so handle and
00:10:42handle func registers the handler
00:10:43function for given pattern in the
00:10:45default serve MUX the defaults for MUX
00:10:48is your server so you can say server you
00:10:50can say router you could say serve mug
00:10:52so you say mugs it’s all pretty much the
00:10:54same the documentation for serve MUX
00:10:59explains how patterns are matched let me
00:11:01just show you so the starting point is
00:11:05HP listen and serve port 8080 mill right
00:11:09meaning to fall serve MUX and with the
00:11:11fall serve MUX we can use handle func
00:11:13HTTP handle func handle func wants a
00:11:16pattern and the string and then a
00:11:19function with that signature that is a
00:11:21type in go you can look at the language
00:11:24speculative speculation you can look at
00:11:27the language spec here’s the language
00:11:29spec and in the language spec you can
00:11:33see all the different types including
00:11:37function types first-class citizens
00:11:40right so we’ve got a type here go back
00:11:44to the documentation which is a function
00:11:46with that signature I’m in the pantry by
00:11:50the way because my kids are asleep I
00:11:52don’t want to make too much noise so
00:11:54it’s like my little sound booth so
00:12:00handle func takes the pattern string
00:12:03which is the route and then it takes a
00:12:05func with this signature so there’s my
00:12:07first func with that signature func
00:12:09index response writer pointer to request
00:12:12response write a pointer to request said
00:12:15now I’m wrapping up my whole deal so
00:12:18this route run this code this route run
00:12:22this code this route run this code
00:12:24that’s it
00:12:25these route from this code it’s totally
00:12:28cool
00:12:29so HB redirect here just to keep it easy
00:12:32keep it restful keep the route to
00:12:34meaningful HP redirect can redirect
00:12:37takes the response writer and by the way
00:12:40this is how servers work client-server
00:12:42architecture right it’s like a request
00:12:45comes in you write a response the
00:12:47request comes into the server to the
00:12:49server writes a response so that’s why
00:12:52this wants that signature because it’s
00:12:54like okay requests came in we got a
00:12:56right response requests came in got a
00:12:58write a response right that’s why you
00:13:01need to function with that signature so
00:13:03redirect takes the response to requests
00:13:06where you want to send and then the
00:13:09status code and that’s just a constant
00:13:11says you know hey it’s 303 the other
00:13:15which means if you come into default you
00:13:18end up getting taken to route books and
00:13:20that’s where you go and that serves this
00:13:23one looks index so if the request method
00:13:26is not yet you’re out of here each to be
00:13:29err can respond and the response writer
00:13:32and then the status text and and status
00:13:35method not allowed and then we return so
00:13:38if you try to post something to this
00:13:40route now we don’t take that method here
00:13:42when we get and then we do a database
00:13:44query and this DB here that comes from
00:13:49go doc I don’t know how much longer I
00:13:53keep going go dog database sequel all
00:13:58right and so here we have the DV stock
00:14:01and you look up at the top package
00:14:06sequel provides a generic interface
00:14:07around sequel databases must be using
00:14:11injunction with a database driver just
00:14:14your drivers car drivers let you drive
00:14:16something let’s go driving and here’s
00:14:21for Poe’s grass so I like this one here
00:14:23we go and you just get that driver get
00:14:30back here so on TV and
00:14:37we can do a query and a queries right
00:14:40here and here’s the query string where
00:14:41you put in your sequel
00:14:43you got any arguments it will take an
00:14:45unlimited 0 to unlimited number of
00:14:47arguments gives you back a pointer to
00:14:49rows so you just get the address back
00:14:52it’s pointer to an address for all the
00:14:54values are stored get a pointer to rows
00:14:57and then there with a pointer to rows
00:15:00you have all these methods available to
00:15:03you so you can do next and scan so you
00:15:07can do a for loop because next returns a
00:15:09bool so you get for loop over the next
00:15:11next next and you can scan and get the
00:15:15values and put it into the destination
00:15:17can we put it into the destination you
00:15:20need that pointer like I said if you
00:15:23don’t understand it could let go coarser
00:15:25so how is that use TB right it goes up
00:15:30here up here I have bar DB and from
00:15:36package sequel right DV I think I might
00:15:40set package TV earlier so that was just
00:15:42me being tired DB query you know from
00:15:47that DB query so pointer to DB x full
00:15:50query because let me just explain ER
00:15:52make sure it’s clear
00:15:54alright so package sequel package sequel
00:15:57package sequel I do open I get a pointer
00:16:02to a DB see that open pointer to DB and
00:16:06open takes a driver name and then like
00:16:09how do you connect to that database and
00:16:11that’s all specified and whatever driver
00:16:13you’re using so up here I create VAR DB
00:16:17from package sequel type DB a pointer to
00:16:21it right and then here I do from package
00:16:25sequel open from package sequel open and
00:16:29then I pass in the driver name Postgres
00:16:33and I pass in the datasource stuff so
00:16:37here it is it’s how you connect Postgres
00:16:39close grass username password then all
00:16:43that stuff move this over come to reason
00:16:47that
00:16:49and so now DB when you do open it gives
00:16:53you back a pointer to a DP with a
00:16:55pointer to DB a value of type DB to be
00:16:59specific with my language when you have
00:17:01a pointer to type DB you have all these
00:17:04methods available I can now run query
00:17:07this one right here so I have a pointer
00:17:10to DB here I ping it just to make sure
00:17:13we really connect to the database and
00:17:16what the pointer to DB I can do that
00:17:18query pass in my sequel and when I do
00:17:23that gives me back roses in there check
00:17:26my air right here there are my rows and
00:17:30then I do my four rows next so that
00:17:32returns a bool long as there’s another
00:17:34record it’ll be true true true false no
00:17:37more records were done and then I do
00:17:40rows scan and I give it give it a
00:17:43pointer to where I want that value
00:17:45stored and I match it up tries the
00:17:49entitled look hot and here I have a
00:17:53slice of book a book is a struck with
00:17:57ISBN title author prices struct is just
00:18:00an aggregate composite data structure
00:18:02and it holds all of your uh all your
00:18:06other data whatever other pieces of data
00:18:08you want to put in there stick them in
00:18:11astruc composes together composite a
00:18:15structure to aggregate aggregates
00:18:17together as much data as you want
00:18:21alright so that’s a book here’s a slice
00:18:25a book which is books so I’m appending
00:18:28two books each book and that pass all
00:18:31those books in here this one I have my
00:18:37templates in go so I pass in books which
00:18:42is a slice and then I range over all
00:18:46those books and for each book I print
00:18:50out the ISBN titled author the price
00:18:55very sweet to beautiful language it’s
00:18:58very elegant really clean once you
00:19:01understand it
00:19:02man codes so nice so that’s books and
00:19:08then the rest of it is a lot like that
00:19:10like books show instead of getting all
00:19:13the books and using query less are just
00:19:17fun past we use query row and that just
00:19:21gives us one row where we’re saying hey
00:19:23where is B n is equal to you know
00:19:27whatever the ISBN is just for and that’s
00:19:29the Postgres right there that’s just how
00:19:32you had done it pass in and identify a
00:19:34parameter to a sequel standard and then
00:19:41it’s the same way the other thing which
00:19:42is neat is a let me see here here’s
00:19:47where we create a book so we get form
00:19:50submissions and you can look at form
00:19:53value here so from my request I want the
00:19:55form value you can go in and look at
00:19:58that and that will give it from the body
00:20:01parameters and forms been submitted or
00:20:04from the URL that’s how form value works
00:20:08so we’re getting it from the URL so just
00:20:11give me the form value or a sign in it
00:20:13we create a book write using the
00:20:15composite literal composite literals the
00:20:18type and then curly braces we’re putting
00:20:21nothing in it so there’s nothing in
00:20:23there yet
00:20:23but then we accept ISBN equal to that
00:20:25title that and then for the price that
00:20:28came back as a string so we now have to
00:20:32take that P and parse it as a float so
00:20:36string convert parse is float we want
00:20:39parse is a float 32 right and I give
00:20:42this back a float
00:20:44sorry parse it as that’s kind of weird
00:20:46float 32 parses float 3 I’m going to
00:20:49check that code and think that’s good
00:20:51for a second here parsefloat converts
00:20:55the string as to a floating-point number
00:20:57with precision specified by bit size 32
00:21:00for float 32 or 64 explode 64 we’re bit
00:21:03size of 32 the result still has type
00:21:06float 64 but it will be convertible to
00:21:08float 32 without changing its value so
00:21:11that was an area my Park can change just
00:21:13that part that’s what
00:21:15you float32 I think it said still
00:21:25float64 there’s ol still has tight
00:21:30float64 so that’s not an era apart
00:21:32change that back so that’s still tight
00:21:35float64 which seems weird it’s 32 now we
00:21:39do DB exec so DB exec is where is it
00:21:46it’s right here so exact execute is how
00:21:51you execute another query right you want
00:21:54to do some of you or excuse some other
00:21:55sequel you don’t just want to do a query
00:21:57a query row but you want to insert or
00:22:00update use XQ and it gives you back a
00:22:02result and air so result just tells you
00:22:05like how many rows were affected or what
00:22:07the results of your executed sequel
00:22:09statement was and and so you do that
00:22:14DB execute and then insert into bugs you
00:22:17know those those those fields in the
00:22:20database and then these values and it
00:22:22inserts record and then updates very
00:22:25similar so you just do here we go update
00:22:29update form oak updates form this one
00:22:33was what create processbook update form
00:22:35here’s book update process and so update
00:22:39process is another DB execute update
00:22:42books set is be into this can it updates
00:22:46it and then delete is just TVXQ delete
00:22:50from books where this is acquired p.m.
00:22:52it’s pretty elegant pretty beautiful you
00:22:55are operating at the level of complete
00:23:00understanding when you use this you have
00:23:02an abstracted away your responsibility
00:23:05as a engineer and a programmer to know
00:23:08what you’re doing
00:23:09and that doesn’t mean we’re all going to
00:23:12build our own CPUs and and write
00:23:15everything in zeros ones we still have
00:23:17strapped away into a language but you
00:23:20understand methods you understand status
00:23:24codes right we’ve got methods here we’ve
00:23:27got status codes
00:23:29you know you’re looking at the forum
00:23:30values coming back you know you’re
00:23:33working in a static language you’re
00:23:35doing your right conversions you’re
00:23:36checking your types you’re doing all of
00:23:39your restful routing it’s really the
00:23:43best way to go you’re not relying on
00:23:44somebody else to build some framework
00:23:47where you don’t really understand the
00:23:50fundamentals and the language you’re
00:23:52working with but are instead up at some
00:23:55abstracted level working in the way
00:23:57somebody else prescribed restricting you
00:24:00not giving you flexibility slowing down
00:24:02your performance you don’t want that you
00:24:04want to learn how to do it real do it
00:24:07right so that’s just a little bit I just
00:24:11have to get this out here man because
00:24:13this stuff is like many years in process
00:24:17to you know get a code pathway and and
00:24:22this solution right here is like the
00:24:25best T sweetest and you know the
00:24:29clearest just this one little example
00:24:32right here this culmination of the
00:24:34Postgres section is actually a
00:24:37culmination of so much of years of work
00:24:40of many people so if you found this to
00:24:43be beneficial and if it gave you insight
00:24:45please like this video and tweet it and
00:24:48share with others even though my voice
00:24:49is all whacked and and I want to I want
00:24:53to get that message out there to people
00:24:55that you know look at how you should be
00:24:57doing go programming web dev we gotta
00:24:59get this video replaced so thanks for
00:25:03watching and I hope this was helpful and
00:25:06if you have any questions or you know
00:25:08anything you can find me on Twitter and
00:25:11I watch that several times a week and so
00:25:13I love connect with people around the
00:25:15world and I think it’s fantastic this
00:25:18amazing world we live in now and so
00:25:20don’t hesitate to reach out if you want
00:25:23to access to my courses for free just
00:25:25let me know be more than happy to help
00:25:26if you don’t have the financial means
00:25:28pay for it it’s my honor to return the
00:25:31favor so many people helped me in life
00:25:33with my education to my honor to give it
00:25:36back all right you all have a good day
”