title: First API Call

description: Build a complete API request with proper error handling and response parsing.

First API Call

Walk through a complete request lifecycle: client setup, request, response, and error handling.

Set up the client

Initialize the SDK client with your API key.

// JavaScript
import Wontopos from "@wontopos/sdk";

const client = new Wontopos(process.env.WONTOPOS_API_KEY, {
  baseUrl: "https://api.wontopos.com",
  timeout: 30000,
});

# Python
import wontopos
import os

client = wontopos.Client(
    api_key=os.environ["WONTOPOS_API_KEY"],
    base_url="https://api.wontopos.com",
    timeout=30.0,
)

// Go
client := wontopos.NewClient(
    os.Getenv("WONTOPOS_API_KEY"),
    wontopos.WithBaseURL("https://api.wontopos.com"),
    wontopos.WithTimeout(30 * time.Second),
)

Make a request

List available APIs from the marketplace.

// JavaScript
const apis = await client.marketplace.list({
  limit: 10,
  status: "active",
});

for (const api of apis.data) {
  console.log(`${api.name} (${api.version})`);
}

# Python
apis = client.marketplace.list(limit=10, status="active")

for api in apis.data:
    print(f"{api.name} ({api.version})")

// Go
apis, err := client.Marketplace.List(ctx, wontopos.MarketplaceListParams{
    Limit:  wontopos.Int(10),
    Status: wontopos.String("active"),
})
if err != nil {
    log.Fatal(err)
}
for _, api := range apis.Data {
    fmt.Printf("%s (%s)\n", api.Name, api.Version)
}

# cURL
curl https://api.wontopos.com/v1/marketplace/apis 
  -H "Authorization: Bearer $WONTOPOS_API_KEY" 
  -G -d limit=10 -d status=active

Handle the response

All responses follow a consistent envelope format.

{
  "data": [...],
  "has_more": true,
  "total_count": 42
}

Error handling

Handle errors gracefully using SDK-specific patterns.

// JavaScript
import { WontoposError, RateLimitError } from "@wontopos/sdk";

try {
  const apis = await client.marketplace.list({ limit: 10 });
} catch (err) {
  if (err instanceof RateLimitError) {
    console.log(`Rate limited. Retry after ${err.retryAfter}s`);
  } else if (err instanceof WontoposError) {
    console.error(`API error: ${err.code} — ${err.message}`);
  } else {
    throw err;
  }
}

# Python
from wontopos.errors import WontoposError, RateLimitError

try:
    apis = client.marketplace.list(limit=10)
except RateLimitError as e:
    print(f"Rate limited. Retry after {e.retry_after}s")
except WontoposError as e:
    print(f"API error: {e.code} — {e.message}")

// Go
apis, err := client.Marketplace.List(ctx, params)
if err != nil {
    var apiErr *wontopos.Error
    if errors.As(err, &apiErr) {
        fmt.Printf("API error: %s — %s\n", apiErr.Code, apiErr.Message)
    } else {
        log.Fatal(err)
    }
}

Common error codes

Next steps

• Environments — Switch between sandbox and production
• Authentication — OAuth 2.0 and scoped tokens
• API Reference — Full endpoint documentation