# Matrix API — Vietmap API Playground

> Calculate distance matrix between multiple points, suitable for logistics and delivery applications (find nearest driver, find shortest/fastest route between multiple points).

The Matrix API (Distance Matrix API) computes travel time and distance between many origins and many destinations in a single call, instead of one Route call per pair. Sources and destinations can be listed separately so only the pairs needed are computed. The result feeds dispatch decisions: the nearest driver for a customer, the depot to serve each order, or input for your own optimiser.

What it is for:
- Finding the nearest driver in a ride-hailing app.
- Choosing the depot that serves each order.
- Filtering stores within a travel-time budget.
- Input for an in-house routing algorithm.

- Interactive page: https://tools.vietmap.vn/playground/en/matrix
- Endpoint: `GET /api/matrix/v4` on `https://maps.vietmap.vn` (giữ /api/matrix?api-version=1.1 để đối chiếu)
- Official documentation: https://maps.vietmap.vn/docs/map-api/matrix-version/matrix-v4/
- API key: every request needs the `apikey` parameter. Samples use `YOUR_API_KEY` as the placeholder — when integrating, read the key from an environment variable (e.g. `VIETMAP_API_KEY`). Get a key at https://maps.vietmap.vn/console-v2/consumers
- Error codes: `401` wrong API key · `403` key restricted to another domain/IP · `423` API not enabled for the key's consumer, or out of credit (body contains "exceeded credit") · `429` rate limit exceeded.

## Code samples

_This is an example request with sample parameters; open the interactive page to change them and run it for real._

### cURL

```bash
curl 'https://maps.vietmap.vn/api/matrix/v4?apikey=YOUR_API_KEY&point=10.776889,106.700806&point=10.818,106.6585&points_encoded=true&vehicle=car&sources=all&destinations=all&annotation=duration'
```

### JavaScript

```javascript
// In production, read the key from an environment variable instead.
const API_KEY = "YOUR_API_KEY";

const params = new URLSearchParams([
  ["apikey", API_KEY],
  ["point", "10.776889,106.700806"],
  ["point", "10.818,106.6585"],
  ["points_encoded", "true"],
  ["vehicle", "car"],
  ["sources", "all"],
  ["destinations", "all"],
  ["annotation", "duration"],
]);

const response = await fetch(`https://maps.vietmap.vn/api/matrix/v4?${params}`);
if (!response.ok) {
  throw new Error(`Vietmap ${response.status}: ${await response.text()}`);
}
const data = await response.json();
console.log(data);
```

### Python

```python
import requests

# In production, read the key from an environment variable instead.
API_KEY = "YOUR_API_KEY"

params = [
    ("apikey", API_KEY),
    ("point", "10.776889,106.700806"),
    ("point", "10.818,106.6585"),
    ("points_encoded", "true"),
    ("vehicle", "car"),
    ("sources", "all"),
    ("destinations", "all"),
    ("annotation", "duration"),
]

response = requests.get("https://maps.vietmap.vn/api/matrix/v4", params=params, timeout=30)
response.raise_for_status()
print(response.json())
```

### URL

```text
https://maps.vietmap.vn/api/matrix/v4?apikey=YOUR_API_KEY&point=10.776889,106.700806&point=10.818,106.6585&points_encoded=true&vehicle=car&sources=all&destinations=all&annotation=duration
```

## AI prompt

A ready-made prompt for a coding assistant (ChatGPT, Claude, Copilot…) to write the integration:

````text
I need to integrate Vietmap's Matrix API v4 into my application.

Official documentation: https://maps.vietmap.vn/docs/map-api/matrix-version/matrix-v4/

Here is a sample request that works in the Vietmap API Playground:

GET https://maps.vietmap.vn/api/matrix/v4?apikey=YOUR_API_KEY&point=10.776889,106.700806&point=10.818,106.6585&points_encoded=true&vehicle=car&sources=all&destinations=all&annotation=duration

Parameters in use:
- point = 10.776889,106.700806
- point = 10.818,106.6585
- points_encoded = true
- vehicle = car
- sources = all
- destinations = all
- annotation = duration

Write code in [my language / framework] that calls this API, with these requirements:
1. Read the API key from the VIETMAP_API_KEY environment variable; never hard-code it.
2. Send the parameters in the query string exactly as in the sample; repeated parameters (such as `point`) must keep their order.
3. Handle Vietmap's HTTP errors:
   - 401: the API key is wrong or revoked.
   - 403: the key is restricted to a domain / IP that does not match.
   - 423: the API is not enabled for the key's consumer, OR the account is out of credit — tell them apart by the response body ("exceeded credit" means out of credit).
   - 429: rate limit exceeded — retry with increasing backoff.
4. Set a request timeout, and define types (type / interface / dataclass) for the response.

If unsure about a field name, look it up in the documentation linked above instead of guessing.
````

## Reopen this exact request in the Playground

https://tools.vietmap.vn/playground/en/matrix?point=10.776889,106.700806&point=10.818,106.6585&version=v4&vehicle=car&annotation=duration