### Example Ecommerce Event Data

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

An example of ecommerce event data for a 'purchase' event, including transaction details and items. This format is used for analysis.

```json
{
  "transaction_id": "123abc",
  "value": 3.99,
  "items": [
    {
      "item_id": "item_1",
      "item_name": "Item 1",
      "item_category": "Numbered Items",
      "item_variant": "1",
      "value": 1.99,
      "quantity": 1
    },
    {
      "item_id": "item_2",
      "item_name": "Item 2",
      "item_category": "Numbered Items",
      "item_variant": "2",
      "value": 2.00,
      "quantity": 1
    }
  ]
}
```

--------------------------------

### gtag.js API Example for GA4 Purchase

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

This is a default example for a GA4 purchase ecommerce event sent using the gtag.js API. Provide the event name and parameters separately.

```javascript
gtag('event', 'purchase', {
  'transaction_id': 'T_12345',
  'affiliation': 'Google Merchandise Store',
  'value': 25.42,
  'tax': 4.90,
  'shipping': 5.99,
  'currency': 'USD',
  'items': [
    {
      'item_id': 'SKU_12345',
      'item_name': 'Stan and Friends Tee',
      'affiliation': 'Google Merchandise Store',
      'coupon': 'SUMMER_FUN',
      'currency': 'USD',
      'item_brand': 'Google',
      'item_category': 'Apparel',
      'item_category2': 'Adult',
      'item_category3': 'Shirts',
      'item_category4': 'Crew',
      'item_category5': 'Short sleeve',
      'item_list_id': 'related_products',
      'item_list_name': 'Related Products',
      'item_variant': 'green',
      'location_id': 'ChIJIQBpAG2ahYAR_PL-W_k-Y-I',
      'price': 9.99,
      'quantity': 1
    }
  ]
});
```

--------------------------------

### Data Layer Push Example for GA4 Purchase

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

This is a default example for a GA4 purchase ecommerce event sent using the dataLayer.push API. Ensure your event object includes an 'event' key.

```javascript
{
  'event': 'purchase',
  'ecommerce': {
    'transaction_id': 'T_12345',
    'affiliation': 'Google Merchandise Store',
    'value': 25.42,
    'tax': 4.90,
    'shipping': 5.99,
    'currency': 'USD',
    'items': [
      {
        'item_id': 'SKU_12345',
        'item_name': 'Stan and Friends Tee',
        'affiliation': 'Google Merchandise Store',
        'coupon': 'SUMMER_FUN',
        'currency': 'USD',
        'item_brand': 'Google',
        'item_category': 'Apparel',
        'item_category2': 'Adult',
        'item_category3': 'Shirts',
        'item_category4': 'Crew',
        'item_category5': 'Short sleeve',
        'item_list_id': 'related_products',
        'item_list_name': 'Related Products',
        'item_variant': 'green',
        'location_id': 'ChIJIQBpAG2ahYAR_PL-W_k-Y-I',
        'price': 9.99,
        'quantity': 1
      }
    ]
  }
}
```

--------------------------------

### gtag.js Ecommerce Event

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

Example of how to send an ecommerce 'purchase' event using gtag.js. This is used when not relying on the Data Layer for ecommerce tracking.

```javascript
gtag('event', 'purchase', {
  "transaction_id": "123abc",
  "value": 3.99,
  "items": [
    {
      "item_id": "item_1",
      "item_name": "Item 1",
      "item_category": "Numbered Items",
      "item_variant": "1",
      "value": 1.99,
      "quantity": 1
    },
    {
      "item_id": "item_2",
      "item_name": "Item 2",
      "item_category": "Numbered Items",
      "item_variant": "2",
      "value": 2.00,
      "quantity": 1
    }
  ]
});
```

--------------------------------

### Example Data Layer Update for Purchase Event

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

This shows how a 'purchase' event and its associated ecommerce data are structured within the Data Layer. This is commonly used with Google Tag Manager.

```json
{
  "event": "purchase",
  "ecommerce": {
    "purchase": {
      "actionField": {
        "id": "123abc",
        "revenue": 3.99
      },
      "products": [
        {
          "id": "item_1",
          "name": "Item 1",
          "category": "Numbered Items",
          "variant": "1",
          "price": 1.99,
          "quantity": 1
        },
        {
          "id": "item_2",
          "name": "Item 2",
          "category": "Numbered Items",
          "variant": "2",
          "price": 2.00,
          "quantity": 1
        }
      ]
    }
  }
}
```

--------------------------------

### Data Layer Push for Ecommerce Event

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

Example of pushing an ecommerce event to the Data Layer using `dataLayer.push()`. This is typically used with Google Tag Manager.

```javascript
dataLayer.push({
  "event": "purchase",
  "ecommerce": {
    "purchase": {
      "actionField": {
        "id": "123abc",
        "revenue": 3.99
      },
      "products": [
        {
          "id": "item_1",
          "name": "Item 1",
          "category": "Numbered Items",
          "variant": "1",
          "price": 1.99,
          "quantity": 1
        },
        {
          "id": "item_2",
          "name": "Item 2",
          "category": "Numbered Items",
          "variant": "2",
          "price": 2.00,
          "quantity": 1
        }
      ]
    }
  }
});
```

--------------------------------

### Custom Event Name Conversion Example

Source: https://github.com/googleanalytics/ecommerce-migration-helper/blob/main/index.html

Illustrates converting a custom event name like 'productClick' to the recommended GA4 event name 'select_item' for compatibility.

```javascript
{
  'event': 'select_item',
  'ecommerce': {}
}
```

--------------------------------

### Fire Test Events and Observe Network Hits

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

This script demonstrates bootstrapping the full tool, including firing test events for both gtag and dataLayer APIs, and setting up a PerformanceObserver to intercept and parse outgoing GA4/UA network hits. It also shows how to identify the schema of an event payload before sending.

```javascript
// Bootstrapping the full tool (simplified equivalent of main.js main())
import ga4 from "./ga4.js";
import measurementProtocol from "./measurement_protocol.js";
import schemaId from "./schema_id.js";
import schemaRecommend from "./schema_recommend.js";

// 1. Fire a test gtag event (gtag API mode)
function gtag() { dataLayer.push(arguments); }

gtag("event", "add_to_cart", {
  currency: "USD",
  value: 19.99,
  items: [{ item_id: "SKU-007", item_name: "Notebook", price: 19.99, quantity: 1 }]
});

// 2. Fire a test dataLayer push (dataLayer mode)
dataLayer.push({ ecommerce: null }); // clear previous ecommerce context
dataLayer.push({
  event: "purchase",
  ecommerce: {
    transaction_id: "TXN-001",
    value: 19.99,
    currency: "USD",
    items: [{ item_id: "SKU-007", item_name: "Notebook", price: 19.99, quantity: 1 }]
  }
});

// 3. Observe outbound hits and route to the correct parser
const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    const url = entry.name;

    if (ga4.isGa4Hit(url)) {
      const parsed = ga4.parse(url);
      // Display parsed data and generate migration recommendation
      console.log("GA4 parsed:", parsed);
      console.log("Recommended command:", schemaRecommend.buildGa4GtagCommand(parsed));
    }

    if (measurementProtocol.isUaLegacyHit(url)) {
      console.log("UA Legacy parsed:", measurementProtocol.parse(url));
    }

    if (measurementProtocol.isUaGa4Hit(url)) {
      console.log("UA+GA4 schema parsed:", measurementProtocol.parse(url));
    }
  });
});
observer.observe({ entryTypes: ["resource"] });

// 4. Identify the schema of an arbitrary event payload before sending
const pendingParams = {
  currency: "USD",
  items: [{ id: "SKU-007", name: "Notebook" }] // UA-style keys
};
const schema = schemaId.identifySchema(schemaId.Api.GTAG, pendingParams);
console.log("Detected schema:", schema); // "ua-gtag" — needs migration to GA4 keys

```

--------------------------------

### schemaRecommend.buildGa4GtagCommand(parsedHitData)

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Generates a recommended GA4 `gtag` command string from a parsed hit data object. This function is useful for migrating existing ecommerce tracking to the GA4 format.

```APIDOC
## `schemaRecommend.buildGa4GtagCommand(parsedHitData)` — Generate a recommended GA4 gtag command

Takes a parsed hit data object (as returned by `ga4.parse()`) and returns a formatted `gtag('event', ...)` string following current GA4 documentation. This output is surfaced directly in the tool's UI as the recommended migration target code.

```js
import ga4 from "./ga4.js";
import schemaRecommend from "./schema_recommend.js";

// Simulate a parsed GA4 hit (e.g., from ga4.parse())
const parsedHit = {
  event: "purchase",
  params: {
    currency: "USD",
    value: "59.98",
    transaction_id: "T-12345"
  },
  products: [
    undefined, // index 0 unused by GA4 encoding
    { item_id: "SKU-001", item_name: "Widget", price: "29.99", quantity: "2" }
  ]
};

const command = schemaRecommend.buildGa4GtagCommand(parsedHit);
console.log(command);
// gtag('event', 'purchase', {
//   'currency': 'USD',
//   'value': '59.98',
//   'transaction_id': 'T-12345',
//   'items': [
//     {
//       'item_id: 'SKU-001',
//       'item_name: 'Widget',
//       'price: '29.99',
//       'quantity: '2',
//     },
//   ],
// });

// --- Full pipeline: intercept a live GA4 hit and generate recommendation ---
const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    if (ga4.isGa4Hit(entry.name)) {
      const parsed = ga4.parse(entry.name);
      const recommended = schemaRecommend.buildGa4GtagCommand(parsed);
      console.log("Recommended GA4 command:\n", recommended);
    }
  });
});
observer.observe({ entryTypes: ["resource"] });
```
```

--------------------------------

### Parse Ecommerce Data from GA4 Hit URL with `ga4.parse()`

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Extracts structured product data, event parameters, and event name from a GA4 Measurement Protocol URL. Products are decoded from a compact encoding, and event parameters are extracted from prefixed query parameters.

```javascript
import ga4 from "./ga4.js";

const ga4HitUrl =
  "https://www.google-analytics.com/g/collect?v=2" +
  "&en=purchase" +
  "&epn.value=29.99" +
  "&epn.tax=2.50" +
  "&ep.currency=USD" +
  "&pr1=id123~nmWidget Pro~pr19.99~qt1~br1Acme~ca1Tools";

const result = ga4.parse(ga4HitUrl);

console.log(result);
// {
//   event: "purchase",
//   products: [
//     undefined,  // index 0 unused
//     {
//       item_id: "123",
//       item_name: "Widget Pro",
//       price: "19.99",
//       quantity: "1",
//       item_brand: "Acme",
//       item_cateogry: "Tools"
//     }
//   ],
//   params: {
//     value: "29.99",
//     tax: "2.50",
//     currency: "USD"
//   }
// }
```

--------------------------------

### measurementProtocol.parse(url)

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Parses a Universal Analytics Measurement Protocol URL to extract ecommerce data such as products, impressions, promotions, and transaction parameters. It maps the two-character field codes to human-readable GA4-aligned field names.

```APIDOC
## `measurementProtocol.parse(url)` — Parse ecommerce data from a UA Measurement Protocol hit

Extracts product fields, impression lists, promotions, and action-level parameters from a Universal Analytics Measurement Protocol URL, mapping all two-character field codes (e.g., `id`, `nm`, `pr`, `qt`) to human-readable GA4-aligned field names.

```js
import measurementProtocol from "./measurement_protocol.js";

const uaUrl =
  "https://www.google-analytics.com/collect?v=1&t=event&el=GTM" +
  "&pr1id=SKU-001&pr1nm=Running+Shoe&pr1pr=89.99&pr1qt=2&pr1br=Nike&pr1ca=Footwear" +
  "&il1nm=Search+Results&il1pi1id=SKU-002&il1pi1nm=Trail+Boot&il1pi1pr=129.99" +
  "&promo1id=PROMO-10&promo1nm=Summer+Sale&promo1cr=banner_top" +
  "&pa=purchase&ti=TXN-42&tr=179.98&tt=14.40&ts=5.99&cu=USD";

const result = measurementProtocol.parse(uaUrl);

console.log(result);
// {
//   products: [
//     undefined,
//     { item_id: "SKU-001", item_name: "Running+Shoe", price: "89.99",
//       quantity: "2", item_brand: "Nike", item_category: "Footwear" }
//   ],
//   impressions: [
//     undefined,
//     { name: "Search+Results", impressions: [
//         undefined,
//         { item_id: "SKU-002", item_name: "Trail+Boot", price: "129.99" }
//       ]
//     }
//   ],
//   promos: [
//     undefined,
//     { item_id: "PROMO-10", item_name: "Summer+Sale", creative_name: "banner_top" }
//   ],
//   params: {
//     product_action: "purchase",
//     transaction_id: "TXN-42",
//     value: "179.98",
//     tax: "14.40",
//     shipping: "5.99",
//     currency: "USD"
//   }
// }
```
```

--------------------------------

### `ga4.parse(url)` — Parse ecommerce data from a GA4 hit URL

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Extracts structured product data, event parameters, and event name from a GA4 Measurement Protocol URL. Products are decoded from the compact `pr<index>=<field><value>~<field><value>` encoding; event parameters are extracted from `ep.` and `epn.` prefixed query params.

```APIDOC
## `ga4.parse(url)` — Parse ecommerce data from a GA4 hit URL

### Description
Extracts structured product data, event parameters, and event name from a GA4 Measurement Protocol URL. Products are decoded from the compact `pr<index>=<field><value>~<field><value>` encoding; event parameters are extracted from `ep.` and `epn.` prefixed query params.

### Method
```javascript
ga4.parse(url: string): object
```

### Parameters
#### Path Parameters
- **url** (string) - Required - The GA4 Measurement Protocol URL to parse.

### Response
#### Success Response
- **event** (string) - The name of the event.
- **products** (array) - An array of product objects, where each object contains details like `item_id`, `item_name`, `price`, `quantity`, etc.
- **params** (object) - An object containing additional event parameters like `value`, `tax`, `currency`.

### Request Example
```javascript
import ga4 from "./ga4.js";

const ga4HitUrl =
  "https://www.google-analytics.com/g/collect?v=2" +
  "&en=purchase" +
  "&epn.value=29.99" +
  "&epn.tax=2.50" +
  "&ep.currency=USD" +
  "&pr1=id123~nmWidget Pro~pr19.99~qt1~br1Acme~ca1Tools";

const result = ga4.parse(ga4HitUrl);

console.log(result);
// {
//   event: "purchase",
//   products: [
//     undefined,  // index 0 unused
//     {
//       item_id: "123",
//       item_name: "Widget Pro",
//       price: "19.99",
//       quantity: "1",
//       item_brand: "Acme",
//       item_cateogry: "Tools"
//     }
//   ],
//   params: {
//     value: "29.99",
//     tax: "2.50",
//     currency: "USD"
//   }
// }
```
```

--------------------------------

### Generate GA4 gtag Command from Parsed Hit Data

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

This function takes a parsed GA4 hit data object and generates a `gtag('event', ...)` command string that conforms to current GA4 documentation. This is useful for displaying recommended migration code.

```javascript
import ga4 from "./ga4.js";
import schemaRecommend from "./schema_recommend.js";

// Simulate a parsed GA4 hit (e.g., from ga4.parse())
const parsedHit = {
  event: "purchase",
  params: {
    currency: "USD",
    value: "59.98",
    transaction_id: "T-12345"
  },
  products: [
    undefined, // index 0 unused by GA4 encoding
    { item_id: "SKU-001", item_name: "Widget", price: "29.99", quantity: "2" }
  ]
};

const command = schemaRecommend.buildGa4GtagCommand(parsedHit);
console.log(command);
// gtag('event', 'purchase', {
//   'currency': 'USD',
//   'value': '59.98',
//   'transaction_id': 'T-12345',
//   'items': [
//     {
//       'item_id: 'SKU-001',
//       'item_name: 'Widget',
//       'price: '29.99',
//       'quantity: '2',
//     },
//   ],
// });

// --- Full pipeline: intercept a live GA4 hit and generate recommendation ---
const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    if (ga4.isGa4Hit(entry.name)) {
      const parsed = ga4.parse(entry.name);
      const recommended = schemaRecommend.buildGa4GtagCommand(parsed);
      console.log("Recommended GA4 command:\n", recommended);
    }
  });
});
observer.observe({ entryTypes: ["resource"] });

```

--------------------------------

### Parse UA Measurement Protocol URL to GA4-aligned fields

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Use this function to extract product, impression, promotion, and transaction data from a Universal Analytics Measurement Protocol URL. It maps UA's two-character field codes to human-readable GA4 field names.

```javascript
import measurementProtocol from "./measurement_protocol.js";

const uaUrl =
  "https://www.google-analytics.com/collect?v=1&t=event&el=GTM" +
  "&pr1id=SKU-001&pr1nm=Running+Shoe&pr1pr=89.99&pr1qt=2&pr1br=Nike&pr1ca=Footwear" +
  "&il1nm=Search+Results&il1pi1id=SKU-002&il1pi1nm=Trail+Boot&il1pi1pr=129.99" +
  "&promo1id=PROMO-10&promo1nm=Summer+Sale&promo1cr=banner_top" +
  "&pa=purchase&ti=TXN-42&tr=179.98&tt=14.40&ts=5.99&cu=USD";

const result = measurementProtocol.parse(uaUrl);

console.log(result);
// {
//   products: [
//     undefined,
//     { item_id: "SKU-001", item_name: "Running+Shoe", price: "89.99",
//       quantity: "2", item_brand: "Nike", item_category: "Footwear" }
//   ],
//   impressions: [
//     undefined,
//     { name: "Search+Results", impressions: [
//         undefined,
//         { item_id: "SKU-002", item_name: "Trail+Boot", price: "129.99" }
//       ]
//     }
//   ],
//   promos: [
//     undefined,
//     { item_id: "PROMO-10", item_name: "Summer+Sale", creative_name: "banner_top" }
//   ],
//   params: {
//     product_action: "purchase",
//     transaction_id: "TXN-42",
//     value: "179.98",
//     tax: "14.40",
//     shipping: "5.99",
//     currency: "USD"
//   }
// }
```

--------------------------------

### Detect UA Legacy-Schema GTM Hit with `measurementProtocol.isUaLegacyHit()`

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Identifies Universal Analytics hits sent by a GTM UA tag configured in legacy-only mode. This is determined by checking for the event label `el=GTM`.

```javascript
import measurementProtocol from "./measurement_protocol.js";

const legacyUrl =
  "https://www.google-analytics.com/collect?v=1&t=event&el=GTM&pr1idSKU-001&pr1nmSneaker";

console.log(measurementProtocol.isUaLegacyHit(legacyUrl)); // true
console.log(measurementProtocol.isUaLegacyHit(
  "https://www.google-analytics.com/collect?v=1&t=event&el=GA4"
)); // false
```

--------------------------------

### `measurementProtocol.isUaLegacyHit(url)` — Detect a UA legacy-schema GTM hit

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Returns `true` if the URL is a Universal Analytics hit fired by the GTM UA tag configured in legacy-only mode (event label `el=GTM`). Used to differentiate legacy UA traffic from GA4-aware UA traffic.

```APIDOC
## `measurementProtocol.isUaLegacyHit(url)` — Detect a UA legacy-schema GTM hit

### Description
Returns `true` if the URL is a Universal Analytics hit fired by the GTM UA tag configured in legacy-only mode (event label `el=GTM`). Used to differentiate legacy UA traffic from GA4-aware UA traffic.

### Method
```javascript
measurementProtocol.isUaLegacyHit(url: string): boolean
```

### Parameters
#### Path Parameters
- **url** (string) - Required - The URL to check for legacy UA GTM hit pattern.

### Request Example
```javascript
import measurementProtocol from "./measurement_protocol.js";

const legacyUrl =
  "https://www.google-analytics.com/collect?v=1&t=event&el=GTM&pr1idSKU-001&pr1nmSneaker";

console.log(measurementProtocol.isUaLegacyHit(legacyUrl)); // true
console.log(measurementProtocol.isUaLegacyHit(
  "https://www.google-analytics.com/collect?v=1&t=event&el=GA4"
)); // false
```
```

--------------------------------

### `measurementProtocol.isUaGa4Hit(url)` — Detect a UA hit with GA4 schema support

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Returns `true` if the URL is a Universal Analytics hit fired by the GTM UA tag with GA4 schema reading enabled (event label `el=GA4`). This distinguishes the tag configuration that can read GA4-style `dataLayer` pushes.

```APIDOC
## `measurementProtocol.isUaGa4Hit(url)` — Detect a UA hit with GA4 schema support

### Description
Returns `true` if the URL is a Universal Analytics hit fired by the GTM UA tag with GA4 schema reading enabled (event label `el=GA4`). This distinguishes the tag configuration that can read GA4-style `dataLayer` pushes.

### Method
```javascript
measurementProtocol.isUaGa4Hit(url: string): boolean
```

### Parameters
#### Path Parameters
- **url** (string) - Required - The URL to check for UA hit with GA4 schema support.

### Request Example
```javascript
import measurementProtocol from "./measurement_protocol.js";

const ga4SchemaUaUrl =
  "https://www.google-analytics.com/collect?v=1&t=event&el=GA4&pr1idSKU-001";

console.log(measurementProtocol.isUaGa4Hit(ga4SchemaUaUrl)); // true
console.log(measurementProtocol.isUaGa4Hit(
  "https://www.google-analytics.com/collect?v=1&t=event&el=GTM"
)); // false
```
```

--------------------------------

### Identify Ecommerce Schema from gtag or dataLayer

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

This function inspects a `gtag` event or `dataLayer` push object to determine which ecommerce schema is being used. It returns an enum value indicating GA4 unified, UA via gtag, UA via GTM, or GTM with GA4 schema.

```javascript
import schemaId from "./schema_id.js";

// --- gtag API with GA4-style items (KnownSchema.UNIFIED = "ga4-gtag") ---
const ga4GtagParams = {
  currency: "USD",
  value: 49.99,
  items: [{ item_id: "SKU-001", item_name: "Gadget", price: 49.99, quantity: 1 }]
};
console.log(schemaId.identifySchema(schemaId.Api.GTAG, ga4GtagParams));
// "ga4-gtag"

// --- gtag API with UA-style items (KnownSchema.GTAG_UA = "ua-gtag") ---
const uaGtagParams = {
  currency: "USD",
  items: [{ id: "SKU-001", name: "Gadget", price: 49.99, quantity: 1 }]
};
console.log(schemaId.identifySchema(schemaId.Api.GTAG, uaGtagParams));
// "ua-gtag"

// --- dataLayer push with UA schema (KnownSchema.GTM_UA = "ua-gtm") ---
const uaDataLayerPush = {
  event: "productClick",
  ecommerce: {
    click: {
      actionField: { list: "Search Results" },
      products: [{ id: "SKU-001", name: "Gadget", position: 1 }]
    }
  }
};
console.log(schemaId.identifySchema(schemaId.Api.DATA_LAYER, uaDataLayerPush));
// "ua-gtm"

// --- dataLayer push with GA4 schema (KnownSchema.GTM_LEGACY_GA4 = "ga4-gtm") ---
const ga4DataLayerPush = {
  event: "purchase",
  ecommerce: {
    transaction_id: "TXN-99",
    value: 99.99,
    items: [{ item_id: "SKU-002", item_name: "Widget", price: 99.99 }]
  }
};
console.log(schemaId.identifySchema(schemaId.Api.DATA_LAYER, ga4DataLayerPush));
// "ga4-gtm"

```

--------------------------------

### Detect UA Hit with GA4 Schema Support with `measurementProtocol.isUaGa4Hit()`

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Determines if a Universal Analytics hit was sent by a GTM UA tag with GA4 schema reading enabled. This is indicated by the event label `el=GA4` and is crucial for identifying tags that can process GA4-style `dataLayer` pushes.

```javascript
import measurementProtocol from "./measurement_protocol.js";

const ga4SchemaUaUrl =
  "https://www.google-analytics.com/collect?v=1&t=event&el=GA4&pr1idSKU-001";

console.log(measurementProtocol.isUaGa4Hit(ga4SchemaUaUrl)); // true
console.log(measurementProtocol.isUaGa4Hit(
  "https://www.google-analytics.com/collect?v=1&t=event&el=GTM"
)); // false
```

--------------------------------

### Detect GA4 Network Hit with `ga4.isGa4Hit()`

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Use this function to filter network requests and identify those that are GA4 data collection hits. It checks if the URL matches the GA4 collection path pattern.

```javascript
import ga4 from "./ga4.js";

const url = "https://www.google-analytics.com/g/collect?v=2&en=purchase&pr1=id1234~nmWidget~pr9.99~qt1";

if (ga4.isGa4Hit(url)) {
  console.log("GA4 hit detected");
  // Output: "GA4 hit detected"
}

// Non-GA4 URL returns false
console.log(ga4.isGa4Hit("https://www.google-analytics.com/collect?v=1&t=event")); // false
```

--------------------------------

### schemaId.identifySchema(api, paramsObject)

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Identifies the ecommerce schema used in a `gtag` event or `dataLayer` push object. It returns a `KnownSchema` enum value indicating whether the schema is GA4 unified, UA via gtag, UA via GTM data layer, GTM with GA4 schema, or unknown.

```APIDOC
## `schemaId.identifySchema(api, paramsObject)` — Identify the ecommerce schema in use

Inspects a `gtag` event params object or a `dataLayer` push object and returns a `KnownSchema` enum value identifying which ecommerce schema it follows: GA4 unified (`ga4-gtag`), UA via gtag (`ua-gtag`), UA via GTM data layer (`ua-gtm`), GTM with GA4 schema (`ga4-gtm`), or `unknown`/`gtag-unknown` when identification fails.

```js
import schemaId from "./schema_id.js";

// --- gtag API with GA4-style items (KnownSchema.UNIFIED = "ga4-gtag") ---
const ga4GtagParams = {
  currency: "USD",
  value: 49.99,
  items: [{ item_id: "SKU-001", item_name: "Gadget", price: 49.99, quantity: 1 }]
};
console.log(schemaId.identifySchema(schemaId.Api.GTAG, ga4GtagParams));
// "ga4-gtag"

// --- gtag API with UA-style items (KnownSchema.GTAG_UA = "ua-gtag") ---
const uaGtagParams = {
  currency: "USD",
  items: [{ id: "SKU-001", name: "Gadget", price: 49.99, quantity: 1 }]
};
console.log(schemaId.identifySchema(schemaId.Api.GTAG, uaGtagParams));
// "ua-gtag"

// --- dataLayer push with UA schema (KnownSchema.GTM_UA = "ua-gtm") ---
const uaDataLayerPush = {
  event: "productClick",
  ecommerce: {
    click: {
      actionField: { list: "Search Results" },
      products: [{ id: "SKU-001", name: "Gadget", position: 1 }]
    }
  }
};
console.log(schemaId.identifySchema(schemaId.Api.DATA_LAYER, uaDataLayerPush));
// "ua-gtm"

// --- dataLayer push with GA4 schema (KnownSchema.GTM_LEGACY_GA4 = "ga4-gtm") ---
const ga4DataLayerPush = {
  event: "purchase",
  ecommerce: {
    transaction_id: "TXN-99",
    value: 99.99,
    items: [{ item_id: "SKU-002", item_name: "Widget", price: 99.99 }]
  }
};
console.log(schemaId.identifySchema(schemaId.Api.DATA_LAYER, ga4DataLayerPush));
// "ga4-gtm"
```
```

--------------------------------

### `ga4.isGa4Hit(url)` — Detect a GA4 network hit

Source: https://context7.com/googleanalytics/ecommerce-migration-helper/llms.txt

Returns `true` if the given URL corresponds to a GA4 data collection hit (matches the `/g/collect?` path pattern). Used to filter the stream of observed network requests down to only GA4 traffic.

```APIDOC
## `ga4.isGa4Hit(url)` — Detect a GA4 network hit

### Description
Returns `true` if the given URL corresponds to a GA4 data collection hit (matches the `/g/collect?` path pattern). Used to filter the stream of observed network requests down to only GA4 traffic.

### Method
```javascript
ga4.isGa4Hit(url: string): boolean
```

### Parameters
#### Path Parameters
- **url** (string) - Required - The URL to check for GA4 hit pattern.

### Request Example
```javascript
import ga4 from "./ga4.js";

const url = "https://www.google-analytics.com/g/collect?v=2&en=purchase&pr1=id1234~nmWidget~pr9.99~qt1";

if (ga4.isGa4Hit(url)) {
  console.log("GA4 hit detected");
}

// Non-GA4 URL returns false
console.log(ga4.isGa4Hit("https://www.google-analytics.com/collect?v=1&t=event")); // false
```
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.