Merge pull request #83 from adobe/claude-2

feat: export CacheOverride API for cross-platform cache control

Author: trieloff

.nycrc.json

@@ -6,5 +6,8 @@
   "check-coverage": true,
   "lines": 20,
   "branches": 80,
-  "statements": 20
+  "statements": 20,
+  "exclude": [
+    "test/fixtures/**"
+  ]
 }

docs/API.md

@@ -1,12 +1,158 @@
-<a name="main"></a>
+# API Documentation
 
-## main(name) ⇒ <code>string</code>
-This is the main function
+## CacheOverride
 
-**Kind**: global function  
-**Returns**: <code>string</code> - a greeting  
+The `CacheOverride` class provides a unified API for controlling cache behavior across both Fastly Compute and Cloudflare Workers platforms.
 
-| Param | Type | Description |
-| --- | --- | --- |
-| name | <code>string</code> | name of the person to greet |
+### Import
 
+```javascript
+import { CacheOverride, fetch } from '@adobe/fetch';
+```
+
+### Constructor
+
+#### `new CacheOverride(mode, init)`
+
+Creates a new CacheOverride instance with the specified mode and options.
+
+**Parameters:**
+
+- `mode` (string): Cache override mode. One of:
+  - `"none"`: Respect origin cache control headers (default behavior)
+  - `"pass"`: Prevent caching regardless of origin headers
+  - `"override"`: Apply custom cache settings
+- `init` (object, optional): Cache configuration options
+
+**Alternative Signature:**
+
+#### `new CacheOverride(init)`
+
+Creates a new CacheOverride instance with `"override"` mode and the specified options.
+
+**Parameters:**
+
+- `init` (object): Cache configuration options
+
+### Cross-Platform Options
+
+The CacheOverride API only includes options that work on **both** Fastly and Cloudflare platforms to ensure true cross-platform compatibility:
+
+| Option | Type | Description | Platform Mapping |
+|--------|------|-------------|------------------|
+| `ttl` | number | Time-to-live in seconds | Fastly: native `ttl`<br>Cloudflare: `cf.cacheTtl` |
+| `cacheKey` | string | Custom cache key | Fastly: native `cacheKey`<br>Cloudflare: `cf.cacheKey` |
+| `surrogateKey` | string | Space-separated surrogate keys for cache purging | Fastly: native `surrogateKey`<br>Cloudflare: `cf.cacheTags` (array) |
+
+**Note:** Platform-specific options (like Fastly's `swr`, `pci`, `beforeSend`, `afterSend`) are intentionally excluded to maintain cross-platform compatibility. If you pass unsupported options, they will be ignored with a console warning.
+
+### Usage Examples
+
+#### Basic TTL Override
+
+```javascript
+import { fetch, CacheOverride } from '@adobe/fetch';
+
+const cacheOverride = new CacheOverride('override', {
+  ttl: 3600  // Cache for 1 hour
+});
+
+const response = await fetch('https://example.com/api', {
+  cacheOverride
+});
+```
+
+#### Prevent Caching
+
+```javascript
+const cacheOverride = new CacheOverride('pass');
+
+const response = await fetch('https://example.com/api', {
+  cacheOverride
+});
+```
+
+#### Advanced Configuration
+
+```javascript
+const cacheOverride = new CacheOverride({
+  ttl: 3600,              // Cache for 1 hour
+  cacheKey: 'my-key',     // Custom cache key
+  surrogateKey: 'api v1'  // Surrogate keys for purging
+});
+
+const response = await fetch('https://example.com/api', {
+  cacheOverride
+});
+```
+
+#### Conditional Caching by Path
+
+```javascript
+import { fetch, CacheOverride } from '@adobe/fetch';
+
+export async function main(request, context) {
+  const url = new URL(request.url);
+  let cacheOverride;
+
+  if (url.pathname.startsWith('/static/')) {
+    // Long cache for static resources
+    cacheOverride = new CacheOverride({ ttl: 86400 });
+  } else if (url.pathname === '/') {
+    // Short cache for homepage
+    cacheOverride = new CacheOverride({ ttl: 60 });
+  } else {
+    // Respect origin cache headers
+    cacheOverride = new CacheOverride('none');
+  }
+
+  return fetch(url, { cacheOverride });
+}
+```
+
+### Platform-Specific Behavior
+
+#### Fastly Compute
+
+On Fastly, `CacheOverride` uses the native `fastly:cache-override` module. Only cross-platform compatible options are passed through to ensure consistent behavior.
+
+```javascript
+// On Fastly, this uses native CacheOverride with cross-platform options
+const override = new CacheOverride('override', {
+  ttl: 3600,
+  cacheKey: 'my-key',
+  surrogateKey: 'homepage main'
+});
+```
+
+#### Cloudflare Workers
+
+On Cloudflare, `CacheOverride` options are automatically mapped to the `cf` object in fetch options:
+
+| CacheOverride | Cloudflare cf object |
+|---------------|---------------------|
+| `mode: "pass"` | `cf: { cacheTtl: 0 }` |
+| `mode: "none"` | No cf options added |
+| `ttl: 3600` | `cf: { cacheTtl: 3600 }` |
+| `cacheKey: "key"` | `cf: { cacheKey: "key" }` |
+| `surrogateKey: "a b"` | `cf: { cacheTags: ["a", "b"] }` |
+
+```javascript
+// On Cloudflare, this is converted to:
+// fetch(url, { cf: { cacheTtl: 3600, cacheKey: 'my-key', cacheTags: ['api', 'v1'] } })
+const override = new CacheOverride({
+  ttl: 3600,
+  cacheKey: 'my-key',
+  surrogateKey: 'api v1'
+});
+
+await fetch(url, { cacheOverride: override });
+```
+
+### Notes
+
+- **Cross-Platform Compatibility**: Only options supported on both platforms are included in this API
+- **Unsupported Options**: If you pass platform-specific options (like `swr`, `pci`, `beforeSend`, `afterSend`), they will be ignored with a console warning
+- **Cloudflare Enterprise**: The `cacheKey` feature requires a Cloudflare Enterprise plan
+- **Surrogate Keys**: On Cloudflare, the space-separated `surrogateKey` string is automatically split into an array for `cf.cacheTags`
+- **For Platform-Specific Features**: If you need platform-specific cache features, use platform detection and native APIs directly instead of the cross-platform `CacheOverride` API

package.json

@@ -5,8 +5,8 @@
   "main": "src/index.js",
   "type": "module",
   "scripts": {
-    "test": "c8 mocha -i -g Integration",
-    "integration-ci": "c8 mocha -g Integration",
+    "test": "c8 --exclude 'test/fixtures/**' mocha -i -g Integration",
+    "integration-ci": "c8 --exclude 'test/fixtures/**' mocha -g Integration",
     "lint": "eslint .",
     "semantic-release": "semantic-release",
     "semantic-release-dry": "semantic-release --dry-run --branches $CI_BRANCH",
@@ -26,7 +26,10 @@
     "require": "test/setup-env.js",
     "recursive": "true",
     "reporter": "mocha-multi-reporters",
-    "reporter-options": "configFile=.mocha-multi.json"
+    "reporter-options": "configFile=.mocha-multi.json",
+    "exclude": [
+      "test/fixtures/**"
+    ]
   },
   "devDependencies": {
     "@adobe/eslint-config-helix": "3.0.14",