WWDC2001 Session 612

Transcript

Kind: captions Language: en good afternoon everybody welcome back to director web I'd like to introduce our next presenter Miguel Sanchez good afternoon everyone can you hear me okay thank you for coming to hear our session on director web I know you probably sick of this polls at the beginning of the sessions but I really need to get a read of how many of you are with objects developers here in the audience now how many of you have used director web okay so there's this is this a good number of people there they're using directory of rules we'll say something like 5% or so so you probably feel a little lonely being the only users of director web right but you know by now we've all been indoctrinated about the relevance of BMW and are you so let's see we can bend some statistics here so we all know that BMW has 3% of the market but for anybody that's been out here in California for more than a week realizes that locally it looks more like this right so it's when you're doing this statistics thing it's very important to have a good grip of your of your universe that you're you're getting your sample from you can't just make up numbers right so we take this thing very seriously in webobjects so over the lunch break I stood over in the corner and I try to count cars and I didn't really find any data that substantiates this but I'm just guessing that but 6% of the remaining people use 76 Ford pintos right and you can't compare apples and oranges but out of those people that use Ford pintos about 90 percent prefer pinto beans in their burritos when they go have Mexican food right so what does this have to do with direct to web not really not nothing not much okay director web is not a technology it's not a technology you can explain with pie charts so you'll have to sit through my presentation of one hour and hopefully you'll get a little more excited this just as a point of reference this is classified as an advanced web object session so I'm assuming some web objects knowledge here this is sort of like if you're already a director web user how I'm sorry a web objects use or how can you take real advantage of director web so you've probably seen in the past it's been demoed in other sessions and we've shown you how director web jump-starts your application in this session I'm going to focus more on how much you can customize your application once once you've started what will we learn I'm going to talk about the architecture of there are two web so you become familiar with what's going on behind this one of these one of the most important things in the architecture of director web is the rule system so I'm going to spend some time explaining to you what the rule system does and of course the recurring theme of the talk is how you can customize director web applications at all kinds of levels brief overview of what director web is director whether it's infrastructure for making your development of web objects applications easier much easier how do we achieve this we achieve this by giving you a lot of pre-built functionality we give you a head start so you don't have to you don't have to start from zero from basically doing nothing other than giving us your database model we give you a full full running application director web is not really an application don't don't expect to find a director web app anywhere in your system rather it's a set of frameworks and tools although I will be referring to director web applications I mean your applications that use director web and director web introduces something new to web objects which is rule-based programming to say to say it one way I'll talk about that what is it director web application most importantly it's a it's a normal web objects application with an HTML front-end and that uses GOF in the back like I said before you probably started with a lot of the pre-built components you we give you and you customize the application we give you either from zero you actually have a running database application without doing anything to quite extensively as I'm going to show you and you know with objects gives you a lot of great runtime flexibility director web adds to that it gives you yet another level in which you can change your application so now we're going to go to a brief demo to show just to to show director web to those that have that have never seen your director level application we get the demo machine up on screen could we get the demo machine up on screen thank you so the starting point for a direct web application is always a database model that we ask from you in addition to the price of web objects so the example we're going to be using throughout our application is a simple bug tracking tool you're all developers you probably all have a need for something like this within your projects we have a very small simple database that has two main tables the bugs which problems you have but on your software the users users can either have created the bugs or be the engineers assigned to fix the bugs and you have look-up tables like the state of the bug and which project it belongs to so that's that's what we start out with once once you have the project and you create a director web project in project builder he uses it oh let me let me stop here for a moment I know I've noticed that a lot of web objects developers out there have been paying very very close attention to our demos and whether we click something or not let me let me come clean on there before to save some time I pre-compile we pre compile some of the applications and we've set some defaults so we're not showing every single step here okay so don't don't spend too much time trying to figure out why why we skip that we just were just trying to save some time here so this is the project having that was created using direct web all you get is a basic template for for a web objects application it has an application classes session and basic very basic components and it knows about the model oh oh you gave us was the model so now let's look at the project in the browser remember you haven't done anything other than prepared your database and giving us your model what do you get for free you get a full fledged database application with a fake login page that's just a starting point for your app it doesn't have any login logic we're just going to log in right now but the application automatically knows about every entity in your model about all the attributes in your model and creates the most generic database access application for it so if we look at the pop up on the left you'll see that this application already knows about bugs and projects and and UN states and users and it gives you the basic pages you would need in any database application to query on them to see that to list the results to edit to edit data so for example let's go to the search page for the bug director web gear gives us this page it knows about all the fields in the bug table in our database we're let's query on it we won't specify any search criteria for the demo here we have a list page here we get all the results from the from the database we can we can go down to a particular page click on the first one please we can look at the Edit we can look at the edit page for to analyze the attributes of the bug so I'm not going to go into much detail here the point is you get this for free so any web object developers out there should at least use direct web as your sort of your database administration until you get this application for free why not use it now of course we can't guess everything you're going to want in your application so you're you're going to want to customize certain things for that we have an applet written in Java running alongside your application which Ernest is going to maximize now which it hung actually we have to restart the app I promised myself that every time this thing crashed I was going to give out a t-shirt I hope it doesn't crash more than twice did you realize the applet or D happens okay so by now you've probably all heard that have if you've been coming to our talks how we're using we're not using the final bits of the Java of the VM RJ drop that's going to be released tomorrow so we the things didn't just didn't come together at the same time so we relaunch we that's also why we're launching it from the command line because we didn't have Java embedding embedded embedded Java running in the browser so anyway we have the applet running alongside our application which allows certain levels of basic customization for example if we go back to the Edit Page you'll see that the title is at the bottom of the page let's say we want to rearrange them so we want to rearrange think of the applet sort of as an inspector into your application and you rearrange the title to be the first thing and then you do your project and then you put the state of the bug as your second thing and here's where the power comes in you save and without restarting your application you refresh and you get the change okay you can do other kinds of things see the project line and the state line those are relationships we want to use another other kinds of components to display them we want to use a little browser to display the available projects that the bug can be assigned to and a little list of radio buttons to display them the list of states that the bug can be assigned to so you have those kinds of components available to you with directive web again he's doing those changes he saves we do a refresh and we see things like that so I'm not going to spend a lot of time actually any more time than this explaining all the little things you can configure with direct web the point is you get an application for free you gave us your model and you can configure it at least that this is the first level you can configure it at now let's go to the project just to briefly show the project the point is the point here is all what you just saw on the screen has for now no code in your project we're not a code generation wizard here okay we didn't just dump out of all these pages for you all of this is being generated dynamically behind the scenes by the director web infrastructure okay so there's really there's no code in your project yet for any of this now could we go back to the slides please can we go back to the slides oh thank you so let's look at the architecture of the apps in a little more detail like I said these are basic web objects application these are normal web blog objects applications using HTML with the app server in the back if we look inside you probably have your code interacting with the uof framework and the web objects framework you would use AOF to access your database giving us get having given us the definition of your database throw in your model and you probably defined a bunch of wall components that give the look of your pages so those are the applications you should all be familiar with being web objects developers director web ivory reiated here as d2w is just another framework you including your project or another framework already included in your project when you have when you create a direct web project like you saw this framework must have a whole bunch of pre-built components to do this to display lists and edits and queries of the of the entities you have in your database now these components are built using normal web objects component there isn't too much trickery here but they have to be configured at runtime by something which we call the rule system the rule system uses information from your ear model to find out about your entities obviously we don't know what they are until you give us one and also from another file we introduced which has the extension d2w model file for now I'll call it a rule file think of it as a text file with a bunch of rules so the rules uses the yo model the rule file and then the components to to to display and configure the application the pages at runtime now let's talk about the rule system in more detail the rule system consists of a set of rules and classes to derive values from those rules it answers questions at runtime we might want to know as developers we might want to know well what background color should I be using to display this string what are the how should I display the property name in case I'm localizing my application which component should I use now so we use the rule system to get an answer to all these things how do we interact with the rule system the first thing the rule system needs to know is that is where our application currently is what is it doing we have to tell at this we have to tell it which task we're trying to perform which entity we're dealing with and more specifically at the entity level which property or attribute were we're handling so that's what the rule system asks from us tell us where you are once you I'm sorry I forgot something in this slide we know we tell the rule system there's something using an instance of a class which we call the d2w context for now think of it as nothing more than a dictionary of key value pairs where you tell it how where your application is once you've initialized one of these contexts and you've told the rule system this is where I am you can now ask it to derive more values you can now say okay so what is the background color I should be using at this point in time what is the display name for property notice that I've shortened the full English questions into into into variable names here the context uses the rules who is a process which we call firing to get information back to us let's give an example here we have a very simple rule set with three rules what kind of information is is specified in this rule in the first rule we say if the task is is edit and the Edit and the entity that we're handling is a bug and somebody asks us what the page name should be the result should be my edit page the second rule says if the property is named and the entity is user and somebody wants to know what the localized name is assuming we're localizing to Spanish we return nombre the third one says if we're listing users and somebody wants to know what table color we should be using we use red ok this is a very simple rule system a very simple rule set but it just hopefully you get to see how the rules look how would this be used by a context let's say we initialize a context with the following two values we say the entity is user and the property is named and we want to know what the localized name is so we initialize the context and we ask the context now derive this value for me the context goes off and says and finds a rule that resolves something about the localized name then it checks on its left-hand side and says does the context I was given bind in with the conditions that this rule specifies and he will find it and it will return us localized name so from a developer's point of view anywhere in our code where we see d2w context dot localized name that will be resolved at runtime to numbering assuming we have initialized the context to these values now this is a very simple example but the rule system is recursive so the end question you might be asking might require several other intermediate steps for the rule system to you to get yet more values to the context so it will ask more questions and initialize itself with yet more values and then in the end it will give you the answer you want so it's recursive now that I've talked a little bit about the rule system let me show you like pull the curtain on director web and show you what the essence of this how do we all the pages that we provide for you really work like I said we use standard web objects components to build our pages the only difference is that these components use the rule system to configure themselves at runtime this is a normal web object component that doesn't use direct to web as ice you should all be familiar with you have an HTML part and a WOD definition let's say that you have your generating some sort of edit page so this is your solution so you even hard code something like name : and the only runtime information you want is the actual value of that name so you introduce a web objects tag and then you resolve that tag using a wool string messaging the current objects name attribute or one thing this is normal web objects programing the pages we provide for you look very similar we have HTML and we have a wad definition but our pages have to be more general than yours because let me go back one page yours says name : there because you know it's your solution we don't know really which attribute we're displaying and until run time so there has to be another dynamic thing that we resolve and in our definite in our bindings file notice the use of d2w context dot display name for property so we we tie into the rule system to find out okay what is internet what is the name of the property I should be displaying now and we do that so components like that is what the direct web framework provides you those are called direct web templates and as you saw in the first demo we give you some basic things we give you pages to do queries we give you pages to edit and to do listing these templates automatically configure themselves to the database model you're using in your particular situation and we use the rule system to get information at one time of course what you're all here for is these can be customized how do you customize them you can customize them at the very basic level like we showed you in the first demo by using the web application web the web assistant applet running alongside your applet you also have full access to the HTML so that's a very high level you can really just redraw the HTML as you as you see fit you also have low level access into into certain components we plug into the page so you might like our HTML but you just want to display your strengths a certain way so you can do that you can plug in your own components so I'm going to show you these two things in the following in the in the next demo do we have the demo machine please so when we last left our application in the prior demo we had this generic database access application that had loose pages and query pages and so here's a list page right now let's say that we're just picky developers and we don't want that that garbage can on the right to show up there and the Edit icon on the left to show up so you just don't want that but then you bring up the web assistant and you realize that I didn't think far enough and I didn't really offer you a way of getting rid of those things using the web assistant no problem you still have access to that page using the web assistant you can tell it please give me the HTML to this page copy the HTML of this page into my project we did it we did this operation before the demo can you bring up the project once the HTML is copied into your project you had you see it can you point to the list yeah there it is so we copied the the actual HTML that direct web uses to generate that page is now copied into your project we can open that HTML in web objects builder and you have full access to it to do to do edits now there's something special about this HTML remember this is the HTML that comes from direct to web is HTML it's HTML that should be able to adapt to all kinds of models so you won't find any references to your particular project in this HTML there'll be a bunch of repetitions and conditionals and no reference to your specific model because all of that is resolved until run time so if we look at the actual raw HTML and the bindings let's look at the bindings there and let's say for example the attributes order there if you look at the line that resolves the display key you will see a reference to the d2w context right so this is the HTML we direct web uses to to draw your applet your page on runtime so it's a very generic form of HTML you will see why that's important in a minute for now can we go back to the page briefly Ernest to show what we wanted to do in Internet Explorer remember we wanted to get rid of the of the of the trashcan and the Edit icon so first let's show that we're actually editing that page Ernest is going to type a little message saying this is my HTML we make the font a little bigger so that you can all see we save and then we we I pre compile the app before before this part of the demo so we were able to refresh the page and just so you know where we are accessing this version of the HTML so now we go back and do the actual changes we wanted to do we wanted to get rid of the trashcan so we look for the trashcan and we just get rid of it we don't want it in our application and we want to change the Edit icon from being an image to a hyperlink with text right so the this is not a session in graphic design so I'm not going to impress you with any fancy HTML editing I just want to show you as developers that you have access to that HTML and you refresh and those are the changes right so you might say well so what that's what HT that's what web objects does yes it's what web objects does but can you bring up the web assistant remember that this is still a direct to web page so on one hand you have access to the HTML and you do to your layout as you as you please but on the other hand look at the title property over can you can you make the browser don't refresh it yeah see the title being there on the right let's say that we want them to move the title over to the left and remove the creation date row column I'm sorry so we can still use the web assistant for that we do save and then we hit refresh right so you don't lose the ability to - to the dynamic aspects of direct web by editing the HTML those that have used direct web in the past and are familiar with freezing pages this is not freezing pages this is generating templates in Prior versions of direct to web you would freeze your page and you have full access to the Java and the HTML but then you would lose this right so that's the high level you're changing the HTML now let's go a little low level do you see where it says description text and resolution those strings are kind of kind of long let's say that you as developers have developed have written a little component that shortened strings that only displays the first 20 characters of your of your string it could be anything else but for demo purposes you have a little component that shortened strings we have such a thing in our in our project can you bring up the project please show the component short string so just a normal web objects component that takes an object and a key binding and if it if it receives a string value that is greater than 20 20 characters it just it just truncates it okay nothing nothing special here what's special is that this could be any one of your components now go back to the page and and the browser now look at look at this we don't stop the app we're still running we go over into the web assistant and we say for the description we want to use a custom component whose name is short string so we type in short string there and we're going to do the same thing for the resolution text so without restarting our application director web is going to know that in that page it should plug in or component so he's doing it for the second one and remember that our component had an object and a key binding so that's how we instantiate your component and we give you the object we want you to display and it's up to you so now remember no restarting the app just refreshing your browser there's our component okay very very simple I mean non non flashy stuff in terms of the HTML we're showing you but I hope that as developers you're seeing the hooks of where you can plug in your your your own code and your own HTML now where let's can you bring up the rule editor for the for the for the for the model bring up the project first and show the resources so you I'm showing you all this without generating much code right so where's all this information about what I should be displaying being stored as we do all these configurations we're creating rules specific to our application those rules are being stored in a file called the user dot d2w model file to look at the file to look at that file you can use a tool called the rule editor can you can you bring up a little please right so all those all those configurations we're doing using the web assistant are you are stored as rules in this file which we use deliver to edit so that's where that's where the magic is going because I haven't been showing you code I've shown you HTML but not code but you're you're noticing that we're I'm changing stuff so where's that information going here that's where it is so that's the end of our second demo can we go back to the to the slides please oh there there sorry does this monitor still shows that so I've given you an overview of the architecture of director web and how the rule system works now let's focus a little more on us developers where let's let's review some of the some of the stuff I show you on the screen and where as developers if you're working on a director application where do you think about plugging in your own HTML or your own code well first of all don't forget that a lot of the things in direct web are now driven by rules so you're all you're used to writing Java and changing component definitions in with objects builder now create another another space in your brain to think about rules you know you know maybe I could do some maybe I don't need to write Java maybe I don't need to change HTML here maybe I could change this with rules so start thinking in terms of can I just is it maybe it's simple enough for me to add a certain rule and my application could be reconfigured so don't don't limit yourself to Java a little bit unrelated to rules but another another point where you can plug in your own code is custom components custom components is what I used on the second demo to shorten the string right so you probably have your own components to display integers or whatever you're displaying your own way you use a custom component for that I'll give a little more detail you also have Java API to invoke direct webpages you might have a web objects application that does not use direct to web or at least in some parts it doesn't use the write to web and then the user clicks somewhere and they want to jump into a dynamic directory web page there's Java API to do that we also have name configurations you might want to reuse a certain page such as query in different in a slightly different style without really rewriting your whole page you can you can define two versions of the page and use it slightly differently I'm going to go into detail into each one of these and you also have Java API to plug in to the rule system rules like I said all of the configuration information where we're doing with rules is stored in two kinds of in two files the configuration you're doing with the web assistant which is the web app let along side your application is stored in the file called user d2w model so anytime you you save your changes in the web assistant they go there you probably don't want to put your own rules there because the web assistant is going to override them unless you're not using the web assistant and and then you're never saving out to that file again yeah but if you're using the web assistant you probably want to put your rules into the second file which is called d2w d2w model file you just add a text file to your project and you start adding rules there that's the second file also remember that your entry point to rules is this thing we call the d2w context so we use key value coding and you do somewhere in your code d2w context dot and then the thing you want to resolve to and it will be resolved to you by the rule system now let's look at custom components for custom components to work you need to implement two bindings or you need to be aware that director web is going to give you two bindings remember custom components are the thing that we're shortening the string so we're going to give you the object that we're working with and the key that we're currently displaying so again having that information you do whatever you want you display that that value as you want using the HTML and and the logic you want so you probably will end up using key value coding somewhere in your component in this in this manner you've seen or key value coding utilities in another session so somewhere in your custom component you're probably going to have a call a line that does this it says okay get me the actual value from the object that you pass me and then you have the value and then you do whatever whatever you want with it and as you saw once you have your custom component you can plug it into you into into application you either using the web assistant or writing your own couple of rules to plug it in you only need to do two rules one saying for this for this property please use the custom component and the custom component name you should use is this direct web api java api to plug into direct web pages you can instantiate and configure direct to web pages from your code using java now you don't use the normal web objects mechanism to call up a page to get to a page that uses director web instead your entry point is the the main class of direct way of d2w and the static method on it called factory so that's that sort of where you met instead of instead of messaging what occasional application your entry point for these kinds of pages is d2w d2w factory now that class implements methods that return all the pages all the kinds of pages that director web provides for you so there are going to be methods in that class that return the edit page for a certain entity the list page for a certain entity the query page for central entity once you get back that page the object you got back implements complies to an interface that we define so that you can configure it so within the director web framework there are certain interface definitions such as edit page interface this page interface and query page interface just to name some which you use to message this page which is just got back to configuration let me give you a more concrete example let's say that you have a web objects application where you're doing your normal stuff and you want to implement a method that returns a direct web list page you already know the data source where the where the data is coming from you just want to show that data up on the screen using a direct web list page so your method would be called something like return a list page method you know that what you're returning is going to implement the list page the list page interface because you're going to be using direct web to get to this page you use the factory to ask for the list page for the entity I don't know what entity notice that e the entity is one of the attributes you pass through this method that that's up to you right so at this point you say T to W factory dot give me the list page for this entity and we ask for a session to do certain to do certain initializations so we give you the list page but that's just a list page without knowing where it's getting its data from or where you want us to go after you're done with it so you use the methods implemented in the list page interface to kind of initialize this page so you do you set the data source where I'm not showing where the data source comes from is here that's that's your responsibility the point is that you tell us and you also tell us what the next page you want to be after you press return on the list page so this is how you would call a list page using the direct Web API or any or any other direct web page named configurations let's say that in the end the application we have remember that we're it's a bug tracking system we have ways of querying on bugs and on users etc let's say that for the query page we have two levels of access for our users we have simple users that only see a limited number of fields they can query on and we have advanced users that see a much much bigger set of fields to query on we want to use the same page so we defined what we call this a named configuration and we give it or whatever name we want and in this case we're going to call it our simple query named configuration and our advanced query named configuration once you have these two configurations I'm going to demo this I'm just showing you the slide you call up the name configuration using the method page for configuration name which behaves to the other methods I have shown you the last thing I want to I want to talk about is how to integrate your own code into the rule system up to now the rules we've shown you are these kinds of very very simple rules that have a condition on the left and I'm sorry I skipped one well this is this is the slide is wrong the instead of localized property name it should have been a constant value that was the first part of the animation so after now we had we had rules that had constant names that they the the things they resolved to work were constant specify the strings remember where it said bug title and things like that but what do you wouldn't it be nice if when you're resolving the value of this rule you're actually calling one of your methods for example localized property value let's say that's your method you you want it define in code how you're going to resolve this rule you can you can implement that method in the subclass of default assignment which is also one of the classes provided in director web here's an example of how you would implement that you have a subclass here called my assignment which is a subclass of default assignment it implements the method you can name it however you want in this case it's called localized property name within the method because you have a subclass of default assignment you have access to the context remember the context is your entry point to the rule system so once you're in the context you can ask at a what's the property I'm working on right now what's the session by the way what is the session I am dealing with and then you do whatever you want with it right I'm not showing you how you localizing here is just the point is that's that's where you do it that's the entry point for you to execute your own code you do whatever you want and then you return a value to us let me show you that with in the in the application do we have the demo machine please [Applause] so this is our application let's review where we are now Ernest just logged into our application and you'll notice that the first page that came up was something which we call the query all page this is the page we're in from which you can query on any entity in your database we don't like that that's what I give you by default you don't like it we're gonna change that what we want to happen when the user logs in is that instead of seeing the query all page they jump right into the bug query page we want to we want to pull them straight into the page where the query on a certain bug because they're looking for bugs but not only that we want to have that page be different depending on the kind of user that logged in if a normal user logged in we only want them to query on two or three attributes if an advanced user logged in an engineer fixing the bug we want them to be able to find bugs and more attributes how do we do that we use a named configuration how do we define a named configuration with rules let's bring up let's bring up the rule editor so here we have the three rules that define our simple query named configuration remember the name is arbitrary you can you can pick whatever you want when you define the name configuration the rule system needs to know okay which task and which entity am I dealing with when you ask for this configuration so that's what the two bottom rules are for it says if the name configuration is simple query the entity is bug that's what we're doing and what we're doing with the bug is querying on it so those are the two things we do then the interesting the interesting rule is the first one can you click on that first one the first rule says if we're in the simple query name configuration and somebody asks us what the display property keys are in other this is just an internal director web key if somebody asks us which which properties of this entity should I display in this case we say Oh first for simple query we only want title description project and creation date for advanced query let's go now to the rules that define the advanced query we're using rule editor we have more rules defined in this file but we're filtering to show you only the ones that are relevant to the demo so for the advanced query again we define that we say the advanced query is something that deals with bugs and we query on bugs and when you ask us what properties you want to display we have a much bigger set of lit a full set of the older properties right so that's how we define the configuration with three rules we're not writing code we will write a couple lines of code right now but we're not rewriting you're out your page so how do we plug in this rules into your page do you remember that and when I gave the first demo I said that the the the login page didn't do anything it was just it was just no logic you just click on the logic and the login button we're going to hook into that page so that when the user clicks in the clicks on the login button by default we take you to the query old page we don't want you we don't want you take you to the query all page we want to check which user logged in if they say if the if a normal user logged in for demo purposes normal users are going to have the login username just user and advanced users are going to have the login username admin so can you go to scroll down to the to the method so the fault page is the method that is executed when you log into the application we have some very simple logic here can you highlight the if the if statement we initialize with the session where you were with the kind of user that we're using and we just do a simple check you know if if the person that logged in is called user let's call up the simple query the simple query name configuration if the person that logged in is named admin let's call up the advanced query query name page if the person that logged in is none of those let's let's bring up the default page that should show up in any in any direct web application we run the application we log out logging is there's nobody right now so we log in as nobody there's a query old page we log out we login as user there is our simple query page we log out we login as admin there's our advanced query page okay again there's very little code to do all this you're defining a lot of this in rules which are stored in a text file and you're in the code you saw there was really just to plug in the the the the page that we wanted to see right after we logged in and to call up the name configuration again where is this query page you haven't even seen it it's it's out in the director web framework and it's working for you the last thing I want to show you in the demo is can you let's let's show the query page again and they're in the browser so here's a query page notice how the names of the of the properties on the left are in English it says title description project state creator creation date assignee and resolution okay but not everybody speaks English in this world we want to localize our application we want to use the rule system to change those titles without writing a lot of code now the director web when it's displaying this page its resolving a binding called display name for property as long as we can hook into that binding and plug in our own code that localizes the name we want to displayed we're okay which is what we're going to do now in the rule and we had disabled that rule by the way so you wouldn't see it in the first part of the demo now we enabled the rule all the rule says is the following it says look at the lower left hand side that's that sort of the condition part of the rule it says if my task is query and the entity I am dealing with this bug and the key I'm trying to resolve is display name for property that's one of the keys that director web uses I want to plug in my own method called localized property name that method is implemented in the custom class called localized string assignment that's that's my own class let's look at that class that's that class is in and we have a very dumb way of localizing things right now we just have a lookup table where we change from from English to Spanish the point of this class is that can you go down to where we implement localized property value or remember this is a subclass of default assignment so we have the method we use the context to get to the property we're displaying and then we figure out which user is logged in and then we use the lookup table so don't don't really pay attention to the details of the method the point is this is where you plug in your own code so now let's see how it looks in our oh the other thing I want to say about this method is for for demo purposes if the if they know if the basic user logs in the one that has the user name user that person speaks English so we won't localize their strings if the advanced user logs in the admin user that person speaks Spanish so we will localize their strings so let's look at the application so we log out let's login as user we are we are executing or localizing code but we're deciding that this person speaks English so we say remember we're using the name configuration we see title description project we logout we login as admin and there we have our page with the with the names of the properties in Spanish ok so quick review of can you log out furnace quick review of what we accomplished with this three demos first you gave us a model we gave you a full-fledged running database application there it is you logged in we have you have all this pages you don't have to write four edits for a list for queries those are there for you can you go to the list page you weren't happy with the pages we gave you from the HTML point of view you changed it you weren't happy with the pages we gave you from the at the property level you plugged in your own component can you log out can you login as user you wanted to reuse one page in two different configurations you define the name configuration and you have a simple and an advanced query configuration can you log out you want it to localize your application and take advantage of the rules of the rule system you you plot you define your own little you're you have your localized code somewhere you you define one rule to resolve the property names in this page and you have a localized page okay that's the end of our direct webcam now that was a very that was a very simple I mean on flashy demo I didn't want to distract from the essence of where the hooks were for you as developers so at this at this time I'd like to bring up on stage Patrice Gautier to show you how he has used the retro web to solve a real-world problem in a in a deployed and currently running application trees thanks Miguel good afternoon so I just want to spend a few minutes and share with you the the absolutely tremendous success we're having with direct toil first thing I'd like to explain is what we do in one slide we're in the business of providing business-to-business infrastructure for real estate for large companies so we have customers like Bank of America Prudential IBM and so on and we provide them with a mean of basically finding landlords engaging them negotiating closing lease and contracts online the process is long and complex typically three to six months and it's made complex because there's a lot of actors touching this process you have the real estate department of these companies you have brokers agents service providers lawyers architects and so on and they all do something at some point in the process so when we model this we end up with a pretty large set of iou's something like 300 so as a developer you know when you start to deal with that volume of data you should be very scared because that means a lot of code for you to write and maintain we have three production application and they have 7700 unique pages in them we also have internal applications so what we decided to do seeing this volume is we decided to beta base almost all of our pages on director web something like 95 percent at the moment is using the very same pages or extended version of these that Miguel showed you we have about 2,200 roles but only 18 templates a lot of our pages come from these templates about 95 percent and what that means is we spent our time mostly doing two things writing business logic writing little custom components like the the component that was shortening the string that Miguel showed you and doing rules only three per page and basically the upshot of all this is that we're able to achieve a tremendous volume of functionality with very few people and a lot less time than our competitors so I have a few screenshots to show you I hope that they're big enough for you see this is an example of this page this is a direct web list page you can see that it looks nothing like what Miguel had it has custom navigation everything you see on this page pretty much is written by rules from the state of the navigation the strings you see on the screen all the names even the the number of items shown per page and so on here's a more interesting page we've added the a wizard creation page which is a stepped wizard and we've added a few feature features to the standard direct web inspect or edit page you can notice if if you can see them that some of the fields have stars on their left which means that they're mandatory one really interesting characteristic of direct web pages is that they know what property of the mother displayed and so they have access to a lot of information that is not typical to a direct webpage they know for example if a property is mandatory because the mouth contains our information so it's just a matter of automatically displaying a star whenever that is the case and that is done automatically you'll have anything to do another thing you can notice is that some of these fields have units on their right that that is worth spending a minute explaining how that works because that it goes at the very heart of the raw power what happened is when we have this app at the beginning it didn't have any of these units and everybody started coming back to us and say well we don't know what parking spaces is expressed as because sometimes it's a ratio sometimes the number spot that you really have to have units so we start thinking about how can we integrate this with the direct web page and the answer it turns out to be really simple we done three three things the first thing we did is add an entry in the user info deck of whatever property were talking about for example parking spaces we would say spaces and the user info dictionary in the model then we add one component that is able to look up that property in this plate on the right of the text field and then we add exactly one rule that says if on the property you're displaying you find the unit in the user info dictionary then use my unit component and without one rule units show up throughout the app throughout 700 pages so you can imagine if you start expanding on that amount of time you were able to save other things of interest on this page notice that we've also completely changed the way validation works all the errors are collected at the top and displayed in a English format here is a an edit tab page again we've changed the way it works we've added sections I don't know if you can see them but there's three tabs and two sections in that tab here's a tab inspect page much the same as the other what I want to show you on this page is how the help system works again direct web doesn't come with a ton of help and you can see here we have two kinds of help we have the level I but ins that are next to each field and that works the same way as the unit basically what we've did is create a help database and let our tech writer access that database through of course a direct web application so he or she accesses that database and creates a help entry for the size range of our project for example the scrubber is that bit of Texas store and database when the app runs again because it knows we're properly displaying it's able to look up that bit of text and display it behind the eye button if you press the I button little Jascha window will pop up with the help and because it knows that it's attached to that property wherever that property shows up in the app the help will be there you don't have to do anything and similarly the help that you see on top of the window comes from the database and our tech writers actually have the ability to edit the help on the direct web app and to see the result of your edit live on the app I don't know how many of you have to deal with web design teams or tech rival teams but typically but it's not what happens you have to ask them for help files integrate them in the app and then have them later look at the result here they can do it live that's a very big advantage and here's a slightly more complex page this is a tab page and has to pick lists in them this is the page that we use to engage or reject responses just to see that you can actually nest direct web pages with indirect web pages you have three in this page so I hope by those few examples I've shown you that two things a direct web is not a toy you can scale to very large amounts of data if you use it properly it'll be a tremendous tool to save time and effort to give you a point of reference our apps the seven apps that I mentioned the beginning were developed by about four to six people over one year our competitors doing the same type of functionality have teams between 30 and 80 people and one last thing I want to mention if you missed the stepwise announcement on Tuesday we are open sourcing four of the base frameworks that are used in those apps you can find them on our website I've posted the URL on Omni and the step wise thank you back can you go whoops thanks for each thank you so in summary the work toya integrates into the web objects development model this isn't any new strange technology that you have to you joining curve for you you already know a lot of what you have to know by being with objects developers we give you a head start with a lot of pre-built functionality we give you an application for free the default layout on behavior can be customized that's that was the main point of the session you you have a lot of places where you can plug in your HTML and your code as developers rules introduce a new level of customization for your direct web applications so think Java would also think a higher Maido level there in your in the way you develop your applications and of course direct aware of rules so there's our lab hours I believe tomorrow is the last day only half date up to 3:30 interesting sessions coming up in this room an advanced talk on EOF after that in the same room the session on advanced Java client which uses the same rule engine of director web which provides a Java front-end to your applications and the feedback form tomorrow contact information you