Shopify

Shopify Best Practices & Common Issues

Webhook Signature Validation

Always validate webhook signatures to ensure authenticity:

// Always validate webhook signatures
String calculatedSignature = ShopifyWebhookUtils.calculateSignature(payload, webhookSecret);
if (!ShopifyWebhookUtils.isValidSignature(receivedSignature, calculatedSignature)) {
  throw new InvalidWebhookSignatureException();
}

Rate Limiting Strategy

• GraphQL: 1000 points/sec (preferred for complex queries)
• REST: 40 calls/sec (legacy operations only)
• Implement exponential backoff with jitter
• Monitor X-Rate-Limit-Remaining headers in responses
• Burst limits: REST has 80 calls burst, GraphQL has 2000 points burst

App Scope Management

// Check required scopes before API calls
List<String> requiredScopes = Arrays.asList("read_products", "write_orders");
if (!ShopifyScopeUtils.hasRequiredScopes(merchant, requiredScopes)) {
  throw new InsufficientScopesException();
}

Common Issues & Solutions

GraphQL vs REST API Decision

• Prefer GraphQL for new implementations (better performance, type safety)
• Use REST only for operations not supported in GraphQL (legacy apps, specific operations)
• Migrate legacy REST implementations to GraphQL when possible
• GraphQL batching reduces rate limit impact

Product Variant Handling

• Shopify has complex variant structures (options + values)
• Variant limits: Max 3 options, Max 100 variants per product
• Careful mapping required to Violet's variant system
• Test variant creation with edge cases (all 3 options, custom options)

Inventory Location Management

• Shopify supports multiple inventory locations
• Handle location-specific stock quantities
• Consider fulfillment location preferences in orders
• Track inventory changes across locations

Metafield Namespace Management

• Use consistent namespacing for Violet-specific data
• violet.offer_id, violet.mapping_id, etc.
• Be aware of metafield storage limits
• Use metafield versioning for breaking changes

Currency Handling

• Shopify supports presentment currencies (store currency + display currency)
• Handle exchange rates for multi-currency orders
• Use PriceUtils.centsToDollars() for accurate conversions
• Test with edge cases: zero-decimal currencies, high-precision currencies

Regional Pricing (Shopify Markets)

Shopify Markets allows merchants to set different prices per country/region using Price Lists and Catalogs.

Querying Regional Prices (Admin API)

Use contextualPricing on ProductVariant to get region-specific prices:

{
  product(id: "gid://shopify/Product/123") {
    variants(first: 10) {
      edges {
        node {
          price              # Base price (store default currency)
          compareAtPrice     # Base compare-at price

          # Regional pricing - pass country code
          contextualPricing(context: { country: GB }) {
            price { amount currencyCode }
            compareAtPrice { amount currencyCode }
          }
        }
      }
    }
  }
}

Key Points

• Base prices (price, compareAtPrice) return the store's default currency
• Contextual prices return the regional currency and adjusted amounts
• Common country codes: US, CA, GB, DE, FR, AU
• Regional prices may differ due to currency conversion, regional adjustments, or region-specific price lists

Storefront API Context

For Storefront API, use the @inContext directive:

query @inContext(country: GB) {
  product(handle: "example") {
    variants(first: 10) {
      edges {
        node {
          price { amount currencyCode }
          compareAtPrice { amount currencyCode }
        }
      }
    }
  }
}

Tax-Inclusive Pricing Detection

Different regions handle sales tax differently:

Detecting Tax-Inclusive Orders (Admin API)

Use draftOrderCalculate mutation to detect if taxes are included:

mutation {
  draftOrderCalculate(input: {
    email: "customer@example.com"
    lineItems: [{
      variantId: "gid://shopify/ProductVariant/123"
      quantity: 1
    }]
    shippingAddress: {
      address1: "123 Example St"
      city: "London"
      zip: "SW1A 1AA"
      countryCode: GB
    }
    presentmentCurrencyCode: GBP
  }) {
    calculatedDraftOrder {
      taxesIncluded          # KEY FIELD: true = tax-inclusive pricing
      presentmentCurrencyCode
      totalPriceSet { presentmentMoney { amount currencyCode } }
      totalTaxSet { presentmentMoney { amount currencyCode } }
      taxLines { title rate priceSet { presentmentMoney { amount currencyCode } } }
    }
    userErrors { field message }
  }
}

Required Input for Accurate Tax Calculation

Third-Party Tax Providers (Avalara)

When merchants use Avalara or other tax apps:

• draftOrderCalculate may use Shopify's fallback rates instead of Avalara
• Storefront checkout may behave differently than Admin API
• "Dynamic tax display" settings can affect API responses
• Always verify API responses match expected storefront behavior

Checkout & Payment

• Support for Shopify Payments and external gateways
• Handle payment intent flows
• Support for multi-currency checkout
• Test with different payment methods

Testing Patterns

Test Structure

• Tests located in src/test/java/io/drizzl/platform/ecom/platforms/shopify/
• Use @SpringBootTest with Shopify-specific mocks
• Comprehensive GraphQL response mocking

Mock Examples

@MockBean
private ShopifyServiceClientFactory shopifyServiceClientFactory;

@MockBean
private ShopifyGraphUtils shopifyGraphUtils;

// Mock GraphQL responses
when(shopifyGraphUtils.executeQuery(any(), any()))
    .thenReturn(mockShopifyGraphqlResponse);

Test Data

• JSON fixtures in src/test/resources/platform/shopify/
• Realistic Shopify API response structures
• Both REST and GraphQL response formats
• Edge cases: null variants, missing fields, large datasets

Debugging Tools

GraphQL Query Testing

• Use Shopify GraphiQL explorer for query development
• Test queries with actual merchant data
• Validate query complexity and performance
• Check query depth (Shopify limits query depth for performance)

Webhook Development

• Use ngrok for local webhook development
• Validate webhook signatures in development
• Test webhook retry behavior
• Monitor webhook delivery timeline

API Client Testing

// Use proxy endpoints for direct API testing
String proxyUrl = "/proxy/shopify/admin/api/2023-04/products.json";
// Test authentication and API responses

Performance Optimization

GraphQL Query Optimization

• Batch multiple operations into single queries
• Request only needed fields
• Use aliases to avoid multiple queries for similar data
• Monitor query complexity score

Rate Limit Optimization

• Use GraphQL for complex operations (better rate limiting)
• Batch REST API calls when necessary
• Implement caching for frequently accessed data
• Monitor rate limit headers and adjust request patterns

Connection Management

• Reuse API client instances
• Implement connection pooling
• Handle graceful degradation under high load

Version Management

• Stay current with Shopify API versions
• Shopify deprecates API versions after 1 year
• Test compatibility with API version changes
• Document version-specific behavior

Security Best Practices

• Never log webhook secrets or access tokens
• Use environment variables for credentials
• Validate all webhook signatures
• Implement API rate limiting detection and alerting
• Use TLS 1.2+ for all API calls
• Validate SSL certificates

Integration Checklist

• GraphQL queries optimized for rate limits
• Webhook signature validation implemented
• Proper error handling for API failures
• Rate limiting with exponential backoff
• Metafield namespacing consistent
• Currency handling tested with edge cases
• Inventory location management properly scoped
• Static architecture patterns followed
• Comprehensive test coverage with mocks
• Production monitoring and alerting configured