Scalable Architecture & System Design

1// Scalable Architecture Patterns
2
3// 1. Configuration-Driven Architecture
4// Use Custom Metadata Types instead of hard-coded values
5public class ConfigurableProcessor {
6    
7    public static void processRecords(List<SObject> records, String processType) {
8        // Read configuration from Custom Metadata
9        List<Process_Config__mdt> configs = [
10            SELECT Handler_Class__c, Is_Active__c, Execution_Order__c
11            FROM Process_Config__mdt
12            WHERE Process_Type__c = :processType
13            AND Is_Active__c = true
14            ORDER BY Execution_Order__c ASC
15        ];
16        
17        for (Process_Config__mdt config : configs) {
18            // Dynamic handler instantiation
19            Type handlerType = Type.forName(config.Handler_Class__c);
20            if (handlerType != null) {
21                IProcessor handler = (IProcessor) handlerType.newInstance();
22                handler.process(records);
23            }
24        }
25    }
26    
27    public interface IProcessor {
28        void process(List<SObject> records);
29    }
30}
31
32// 2. Feature Flags using Custom Metadata
33public class FeatureFlags {
34    
35    private static Map<String, Feature_Flag__mdt> flags;
36    
37    static {
38        flags = new Map<String, Feature_Flag__mdt>();
39        for (Feature_Flag__mdt flag : [
40            SELECT DeveloperName, Is_Enabled__c, Rollout_Percentage__c
41            FROM Feature_Flag__mdt
42        ]) {
43            flags.put(flag.DeveloperName, flag);
44        }
45    }
46    
47    public static Boolean isEnabled(String featureName) {
48        Feature_Flag__mdt flag = flags.get(featureName);
49        if (flag == null) return false;
50        
51        if (flag.Rollout_Percentage__c != null && flag.Rollout_Percentage__c < 100) {
52            // Percentage-based rollout
53            Integer hash = Math.abs(UserInfo.getUserId().hashCode());
54            return Math.mod(hash, 100) < flag.Rollout_Percentage__c;
55        }
56        
57        return flag.Is_Enabled__c;
58    }
59}
60
61// Usage in code:
62// if (FeatureFlags.isEnabled('New_Pricing_Engine')) {
63//     NewPricingEngine.calculate(opp);
64// } else {
65//     LegacyPricing.calculate(opp);
66// }
67
68// 3. Multi-Org Data Architecture
69public class CrossOrgDataService {
70    
71    // Using Salesforce Connect / External Objects
72    // External_Account__x maps to Account in another org
73    
74    public static List<External_Account__x> getExternalAccounts(String industry) {
75        return [
76            SELECT ExternalId, Name__c, Industry__c, Revenue__c
77            FROM External_Account__x
78            WHERE Industry__c = :industry
79            LIMIT 100
80        ];
81    }
82    
83    // Org-to-Org sync via Named Credentials
84    @future(callout=true)
85    public static void syncToSecondaryOrg(Set<Id> accountIds) {
86        List<Account> accounts = [
87            SELECT Id, Name, Industry, AnnualRevenue
88            FROM Account WHERE Id IN :accountIds
89        ];
90        
91        HttpRequest req = new HttpRequest();
92        req.setEndpoint('callout:Secondary_Org/services/apexrest/api/accounts');
93        req.setMethod('POST');
94        req.setHeader('Content-Type', 'application/json');
95        req.setBody(JSON.serialize(accounts));
96        
97        HttpResponse res = new Http().send(req);
98        if (res.getStatusCode() != 200) {
99            System.debug('Sync failed: ' + res.getBody());
100        }
101    }
102}