Exploring on Salesforce: Display Google Map using Salesforce Lightning Web Components leveraging modern JavaScript

Motivation behind this

Currently I am exploring Lightning Web Components (LWC) and trying to display Google map using LWC leveraging modern JavaScript (ES6 Standard). Since modern JavaScript has new functions like Spread function, Arrow function which are well blended into LWC JavaScript controller and hence, drives me to come out with this proof-of-concept.

Use Case

Business has a requirement to display their various office locations in the Google Map which will get retrieved from Salesforce Account Object.

Developer wants to build this requirement using Lightning Web Components.

Expected Outcome

In the above picture I am displaying our company office locations (Bangaluru and Noida) in Google Map. I have taken only 2 locations for simplicity.

Solution Approach

Salesforce provides lightning-map component which displays one or more locations. It inherits the styling from map of Lighting Design System.

So, it is better to use it.

Syntax for using lightning-map component

<template>
    <lightning-map
 map-markers={mapMarkers}
 markers-title="Our Company Location">
  </lightning-map>
</template>

A marker contains

Location Information: A coordinate pair of latitude and longitude, or an address composed of address elements.
Descriptive Information: Optional title, description, and an icon. These are relevant to the marker but not specifically related to location.

For more information, refer lightning-map documentation

Little bit homework for preparing data

Since data to be displayed dynamically from database, so created 2 Account records with a name starts with Tavant providing complete BillingAddress information. I have not given Latitude and Longitude as Location which can also be used alternatively.

Let's first construct the Apex class.

DisplayMapController.cls

getOfficeLocations method accepts accountNameInitial as input parameter and returns List of Accounts based on SOQL query. We are not doing any data transformation which can be recognized in map display, rather let it be handled by LWC js controller will be mentioned below.

Note:
@AuraEnabled (cacheable=true) used as it will be called from js controller and @wire is calling the method
Secondly, use of bind (:str) variables to get rid of SOQL injection.

public with sharing class DisplayMapController {
    
    @AuraEnabled (cacheable=true)
    public static List<Account> getOfficeLocations(String accountNameInitial){
        String str = accountNameInitial + '%';
        return [SELECT Id, Name, BillingStreet, BillingCity, BillingState, BillingPostalCode, BillingCountry 
                FROM Account 
                WHERE Name LIKE :str];       
    }
}

Let's develop Lightning Web Components

Create a VSCode project with a menu selection SFDX: Create Lightning Web Component and provide a name displayLWCMap, which creates 3 files html (UI) , js (Controller) and xml (Configuration) at your chosen directory.

displayLWCMap.html

Inside the template lightning-map component has been used and also zoom-level has been used as additional attribute apart from map-markers and markers-title.

<template>
    <div class="slds-m-around_medium">
        <h1 class="slds-text-heading_small">Tavant Technologies</h1>
        <p class="slds-text-body_regular">Office locations</p>
    </div>
    <lightning-map 
        map-markers={mapMarkers}
        markers-title={markersTitle}
        zoom-level={zoomLevel}>
    </lightning-map>   
</template>

displayLWCMap.js

Good thing of LWC is handling all attributes as js controller level which is opposed to Aura and this class is most important for implementing this functionality.

Follow these steps:

import LightningElement, api, wire, track which will be used in this class.
import getOfficeLocations as we will be using getOfficeLocations method of DisplayMapController apex class.
At the class level,

accountNameParam which is public reactive property decorated with @api
error, mapMarkers, markersTitle and zoomLevel are private reactive properties

@wire to function i.e getOfficeLocations and passing parameter '$accountNameParam' for accountName (here, parameter has been hard coded, though it can passed from html)

This is function, retrieve the data and prepare mapMarkers array with location, icon and title which should be recognized and used in the lightning-map.

import { LightningElement , wire, track, api} from 'lwc';

import getOfficeLocations from '@salesforce/apex/DisplayMapController.getOfficeLocations';

export default class DisplayLWCMap extends LightningElement {

    @api accountNameParam; 
    accountNameParam = 'Tavant';
    @track error;   //this holds errors

    @track mapMarkers = [];
    @track markersTitle = 'Tavant Technologies';
    @track zoomLevel = 4;
    /* Load address information based on accountNameParam from Controller */
    @wire(getOfficeLocations, { accountNameInitial: '$accountNameParam'})
    wiredOfficeLocations({ error, data }) {
        if (data) {            
            data.forEach(dataItem => {
                this.mapMarkers = [...this.mapMarkers ,
                    {
                        location: {
                            City: dataItem.BillingCity,
                            Country: dataItem.BillingCountry,
                        },
        
                        icon: 'custom:custom26',
                        title: dataItem.Name,
                    }                                    
                ];
              });            
            this.error = undefined;
        } else if (error) {
            this.error = error;
            this.contacts = undefined;
        }
    }

}

displayLWCMap.js-meta.xml

This is configuration file which states where this component will be available.

<?xml version="1.0" encoding="UTF-8"?>
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata" fqn="displayLWCMap">
    <apiVersion>45.0</apiVersion>
    <isExposed>true</isExposed>
    <targets>
    <target>lightning__AppPage</target>
    <target>lightning__RecordPage</target>
    <target>lightning__HomePage</target>
  </targets>
</LightningComponentBundle>

Leveraging Modern JavaScript

Arrow Function

You can observe that following statement has been used which doesn't have function() and return statement.

data.forEach(dataItem => {
  //method body without return statement
}

For example, earlier we use write this way to using function and return statement.

let result = function (a,b) {
  return a+b; 
}
console.log(result(1,2));

Now, with Arrow function, it can be written as:

let result = (a,b) => return a+b; 

console.log(result(1,2))

Also, Arrow function resolves some confusion when dealing with this keyword, when nested functions are involved. Functions have a special variable called this, often referred to as the “dynamic this,” which refers to the object used to invoke the function.

For more information, Refer Understand JavaScript Functions

Spread Operator

Spread operator helps to expand the array which we have used for creating mapMarkers array. Here is an example:

let arr = ['a','b']; 
let arr2 = [...arr,'c','d']; 
  
console.log(arr2); // [ 'a', 'b', 'c', 'd' ]

We can see, arr values has been appended first and then c and d have been added to the same array.

Similarly, we can append array values at end the array too.

let arr = ['a','b']; 
let arr2 = ['c','d',...arr]; 
  
console.log(arr2); // [ 'c', 'd', 'a', 'b']

For more information, refer javascript-spread-operator

Finally, after deployment, create a Lightning App page (just for testing) and add this displayLWCMap component on the page. It will display the 2 office locations plotted in Google Map.

Exploring on Salesforce

Pages

Sunday, July 28, 2019

Display Google Map using Salesforce Lightning Web Components leveraging modern JavaScript