Background
Greenhouse Monitoring System will be taken as an example to illustrate creating User Interface applications using TQL Queries.
TQL Queries Vs REST Services
REST is an architecture style for designing networked applications and in virtually all cases, the HTTP protocol is used. In many ways, the World Wide Web itself, based on HTTP, can be viewed as a REST-based architecture. By this definition of REST coupled with the fact that TQL Queries are executed over an HTTP endpoint that is automatically generated when models are deployed to TQLEngine, make TQL Queries Restful in nature.
In the table below we note fixed REST pattern that is applicable to TQL Queries.
TQL Queries | Restful Services |
---|---|
XML Oriented (Request & Response) (Note that TQLEngine supports both JSON & XML; the recommended guideline is XML for TQL Queries readability) | Restful Services are JSON oriented |
TQL Queries are sent as payload, therefore the HTTP Method to be used always POST. | Method can be: GET/PUT/POST/DELETE |
UI Technologies
Most commonly used UI technologies are:
- HTML,CSS and JavaScript
- JavaScript Frameworks (Angular JS, Backbone JS, etc.)
- HTML5, CSS/CSS3 and JavaScript/jQuery
Design Patterns
Model-View-Controller (MVC) is popular design pattern to develop HTML/JS app that consumes TQL Queries.
View | Technology | In this tutorial |
---|---|---|
View | HTML, CSS, JS (Bootstrap is a good starting point) | index.html |
Model | JS - Services & Factories independent of underlying framework (OR) Angular JS provided Model | Angular Model Service (TQLQueryService.js) |
Controller | JS - Can be independent of underlying framework (Write your own using JS) or Angular provided model | Angular Controller and bind with HTML using Angular directive ng-controller. [MainController.js] |
Implementation Steps
All the implementation steps must be against Simulated Greenhouse project.
Creating View
a) Main View - Single Page HTML file
<!DOCTYPE html> <html ng-app="GreenhouseUIApp"> <head> <title>Smart Greenhouse</title> <script src="https://code.jquery.com/jquery-2.2.3.min.js"></script> <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.5/angular.min.js"></script> <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet"> <link href="style.css" rel="stylesheet"> <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/x2js/1.2.0/xml2json.min.js"></script> <script type="text/javascript" src="config/url_config.js"></script> <script type="text/javascript" src="controllers/mainController.js"></script> <script type="text/javascript" src="services/queryService.js"></script> </head> <body> <div ng-controller="mainController"> <div class="row text-center header"> <h2>SMART GREENHOUSE</h2> </div> <div class="row text-center greenhouseDetails"> <h4>{{selectedGreenhouse.GreenhouseName}} | Zones: {{selectedGreenhouse.ZoneCount}} | Location: ({{selectedGreenhouse.Location.latitude}}, {{selectedGreenhouse.Location.longitude}})</h4> </div> <div class="row"> <div class="col-md-2"></div> <div class="col-md-3 statusBlock"> <div> <h3>Internal Status</h3> </div> <div>Temperature: {{selectedGreenhouse.InternalEnv.Temperature}} °C</div> <div>Humidity: {{selectedGreenhouse.InternalEnv.Humidity}} %</div> <div>Amb. Light: {{selectedGreenhouse.InternalEnv.Light}} lux</div> <div>Soil Moisture: {{selectedGreenhouse.InternalEnv.SoilMoisture}} cb</div> </div> <div class="col-md-1"></div> <div class="col-md-4 statusBlock"> <div> <h3>External Conditions</h3> </div> <div>Temperature: {{selectedGreenhouse.ExternalEnv.Temperature}} °C</div> <div>Humidity: {{selectedGreenhouse.ExternalEnv.Humidity}} %</div> <div>Sunlight: {{selectedGreenhouse.ExternalEnv.Light}} lux</div> <div>Soil Moisture: {{selectedGreenhouse.ExternalEnv.SoilMoisture}} cb</div> <div>Wind: {{selectedGreenhouse.ExternalEnv.Wind}} mph</div> </div> <div class="col-md-3"></div> </div> </div> </body> </html>
b) Creating Style Sheet
body{ background: url(images/greenhouse.jpg); background-size: cover; padding: 0; margin: 0; } .header{ background: #000; color: #fff; margin-bottom: 20px; } .greenhouseDetails{ background: #39404a; color: #fff; } .statusBlock{ background: #39404a; color: #fff; padding: 30px; margin: 30px 0; }
Creating Model
Model is where we capture consuming of TQL Queries.
Identify Queries
Before we start wrapping TQL Queries into a Service model, we need to identify the list of queries to be executed.
Discovering TQL EndPoints URL:
Application TQL endpoint discovery query<Query> <Find> <project> <projName eq='Greenhouse'/> </project> </Find> </Query> <GetProjectEndPoints> <ProjectSysId> Find.Result.Project.SysId </ProjectSysId> </GetProjectEndPoints>
Never hardcode the TQL Query endpoint urls as they are subject to change.
Instead the endpoints must be auto discovered given the project name.
The model developer (owner) will project you appropriate project name to discover your query endpoints.
- You can test the queries and make sure they are working via Query Editor (TQLStudio or Local TQLEngine)
Gather App related queries: In this example we will wrap only one single query to get Greenhouse information.
App Queries - Greenhouse Monitoring App<Query> <Find> <Greenhouse> <GreenhouseID ne=''/> </Greenhouse> </Find> </Query>
Creating Controller
angular.module('GreenhouseUIApp', []) .controller('mainController', function($scope, QueryService) { $scope.greenhouses = []; $scope.httpEndpoint = ""; $scope.wsEndpoint = ""; $scope.getGreenhouses = function(){ QueryService.getGreenhouses($scope.httpEndpoint).then(function(response){ if(angular.isArray(response.Find.Result.Greenhouse)){ $scope.greenhouses = response.Find.Result.Greenhouse; } else if(angular.isObject(response.Find.Result.Greenhouse)){ $scope.greenhouses.push(response.Find.Result.Greenhouse); } $scope.selectedGreenhouse = $scope.greenhouses[0]; console.log($scope.greenhouses); }); }; $scope.replaceIPWithHostName = function(){ $scope.wsEndpoint = $scope.wsEndpoint.replace( /:.*?\:/, '://'+greenhouseHostName+':' ); $scope.httpEndpoint = $scope.httpEndpoint.replace( /:.*?\:/, '://'+greenhouseHostName+':' ); }; QueryService.discoverGreenhouseEndpoint().then(function(data){ angular.forEach(data.Find.projectEndpointMap.DataMap, function(obj){ if(obj.Value.indexOf("ws:") > -1){ $scope.wsEndpoint = obj.Value; } else if(obj.Value.indexOf("http:") > -1 || obj.Value.indexOf("https:") > -1){ $scope.httpEndpoint = obj.Value; } }); $scope.replaceIPWithHostName(); $scope.getGreenhouses(); }); }
Deploy & Test
It is recommended to serve your applications (html,css,js) files directly from the running TQLEngine.
Download & Install TQLEngine
Please refer to download section to download and install TQLEngine.
Attach applications to the project (Locally) (Even if it is part of different Project)
Now you can point your browser to URL and load the UI