Testing and Debugging Directives

Testing and Debugging Directives

Effective CSP implementation requires thorough testing of directive interactions:

// CSP testing utility
class CSPTester {
    constructor(policy) {
        this.policy = policy;
        this.violations = [];
    }
    
    testResource(resourceType, source) {
        const directive = this.getEffectiveDirective(resourceType);
        const allowed = this.isSourceAllowed(directive, source);
        
        if (!allowed) {
            this.violations.push({
                directive: directive,
                source: source,
                resourceType: resourceType
            });
        }
        
        return allowed;
    }
    
    getEffectiveDirective(resourceType) {
        // Check for specific directive
        if (this.policy[`${resourceType}-src`]) {
            return `${resourceType}-src`;
        }
        // Fall back to default-src
        return 'default-src';
    }
    
    generateReport() {
        return {
            policy: this.policy,
            violations: this.violations,
            coverage: this.calculateCoverage()
        };
    }
}

Understanding CSP directives thoroughly enables you to create policies that provide maximum security while maintaining application functionality. Each directive serves a specific purpose in your defense strategy, and their careful combination creates a comprehensive security posture. As you implement CSP, start with permissive policies and gradually tighten them based on your application's actual needs, using violation reports to guide your decisions. Remember that the most secure policy is one that's actually deployed and working, not a theoretically perfect policy that breaks your application.## How to Implement CSP Headers - Step by Step Tutorial

Implementing Content Security Policy headers requires careful planning and a systematic approach to ensure security without breaking functionality. This comprehensive tutorial walks through the entire implementation process, from initial setup to production deployment, covering various server configurations and frameworks. Whether you're securing a simple static site or a complex web application, this guide provides practical steps for successful CSP implementation.