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# List Invoices

GET https://api.coperniq.io/v1/invoices

Retrieve a paginated list of invoices.

Supports:
- Pagination (`page_size`, `page`)
- Date filtering (`updated_after`, `updated_before`)
- Sorting (`order_by`)


Reference: https://docs.coperniq.io/api-reference/invoices/list-invoices

## Authentication

- `x-api-key` header (required) — API Key authentication via header

## Request

### Query parameters

- `page_size` (integer, optional, default: 20) — Number of items per page (max 100)
- `page` (integer, optional, default: 1) — Page number (1-based)
- `order_by` (enum, optional, default: asc) — Sort order for results
  - Allowed values: `asc`, `desc`
- `updated_after` (InvoicesGetParametersUpdatedAfter, optional) — Filter items updated after this timestamp (ISO 8601). Also matches records whose custom property values changed within the window.
- `updated_before` (InvoicesGetParametersUpdatedBefore, optional) — Filter items updated before this timestamp (ISO 8601). Also matches records whose custom property values changed within the window.

## Response

### 200

List of invoices

- `list of Invoice`

## Errors

### 400 Bad Request Error

Invalid request

- `message` (string, optional)
- `code` (enum, optional)
  - Allowed values: `UNAUTHORIZED`
- `field` (string, optional) — Field that caused the validation error (if applicable)

### 401 Unauthorized Error

Authentication failed

- `message` (string, optional)
- `code` (enum, optional)
  - Allowed values: `UNAUTHORIZED`

## Types

### InvoicesGetParametersUpdatedAfter

- string
- string

### InvoicesGetParametersUpdatedBefore

- string
- string

### Invoice

- `id` (integer, required) — Invoice identifier
- `invoiceNumber` (integer, required) — Unique invoice number
- `status` (enum, required) — Invoice status
  - Allowed values: `DRAFT`, `SENT`, `DECLINED`, `PAID`, `PARTIALLY_PAID`, `OVERDUE`
- `amount` (double, required) — Total invoice amount
- `amountPaid` (double, required) — Amount paid
- `calculationMethod` (string, required) — Calculation method (e.g., LINE_ITEMS)
- `createdAt` (string, required) — Creation timestamp
- `updatedAt` (string, required) — Last update timestamp
- `description` (string, optional, nullable) — Invoice description
- `internalMemo` (string, optional, nullable) — Internal-only memo, never shown to customers or on the PDF or portal. Rich text (HTML, like the app's editor stores). On update, send null or "" to clear it; responses return null when empty. Invoices and bills created in the app from a quote or purchase order inherit its memo.
- `basedOnId` (integer, optional, nullable) — ID of the record this invoice is based on
- `basedOnUid` (integer, optional, nullable) — UID of the record this invoice is based on
- `dueDate` (string, optional) — Due date
- `issueDate` (string, optional, nullable) — Issue date when the invoice has been issued
- `isArchived` (boolean, optional) — Whether the invoice is archived
- `sharedWithPortal` (boolean, optional) — Whether the invoice is shared with portal
- `percentage` (double, optional, nullable) — Percentage if applicable
- `baseAmount` (double, optional, nullable) — Base amount if applicable
- `account` (InvoiceAccount, optional, nullable)
- `record` (InvoiceRecord, optional, nullable)
- `lineItems` (list of InvoiceLineItem, optional)

### InvoiceAccount

- `id` (integer, optional)
- `title` (string, optional)

### InvoiceRecord

- `id` (integer, optional)
- `uid` (integer, optional)
- `title` (string, optional)

### InvoiceLineItem

- `id` (integer, required) — Line item identifier
- `catalogItemId` (integer, required) — Catalog item identifier
- `quantity` (integer, required) — Quantity
- `unitCost` (double, required) — Cost per unit
- `unitPrice` (double, required) — Price per unit
- `description` (string, optional, nullable) — Line item description
- `catalogItem` (InvoiceLineItemCatalogItem, optional, nullable)

### InvoiceLineItemCatalogItem

- `id` (integer, optional)
- `name` (string, optional)
- `manufacturer` (string, optional, nullable)
- `sku` (string, optional, nullable)
- `type` (enum, optional)
  - Allowed values: `PRODUCT`, `SERVICE`

## Examples

**Response**

```json
[
  {
    "id": 1,
    "invoiceNumber": 1,
    "status": "DRAFT",
    "amount": 1.1,
    "amountPaid": 1.1,
    "calculationMethod": "string",
    "createdAt": "2024-01-15T09:30:00Z",
    "updatedAt": "2024-01-15T09:30:00Z",
    "description": "string",
    "internalMemo": "string",
    "basedOnId": 1,
    "basedOnUid": 1,
    "dueDate": "2024-01-15T09:30:00Z",
    "issueDate": "2024-01-15T09:30:00Z",
    "isArchived": true,
    "sharedWithPortal": true,
    "percentage": 1.1,
    "baseAmount": 1.1,
    "account": {
      "id": 1,
      "title": "string"
    },
    "record": {
      "id": 1,
      "uid": 1,
      "title": "string"
    },
    "lineItems": [
      {
        "id": 1,
        "catalogItemId": 1,
        "quantity": 1,
        "unitCost": 1.1,
        "unitPrice": 1.1,
        "description": "string",
        "catalogItem": {
          "id": 1,
          "name": "string",
          "manufacturer": "string",
          "sku": "string",
          "type": "PRODUCT"
        }
      }
    ]
  }
]
```

**SDK Code**

```python
import requests

url = "https://api.coperniq.io/v1/invoices"

headers = {"x-api-key": "<apiKey>"}

response = requests.get(url, headers=headers)

print(response.json())
```

```javascript
const url = 'https://api.coperniq.io/v1/invoices';
const options = {method: 'GET', headers: {'x-api-key': '<apiKey>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.coperniq.io/v1/invoices"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("x-api-key", "<apiKey>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://api.coperniq.io/v1/invoices")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Get.new(url)
request["x-api-key"] = '<apiKey>'

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.get("https://api.coperniq.io/v1/invoices")
  .header("x-api-key", "<apiKey>")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('GET', 'https://api.coperniq.io/v1/invoices', [
  'headers' => [
    'x-api-key' => '<apiKey>',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://api.coperniq.io/v1/invoices");
var request = new RestRequest(Method.GET);
request.AddHeader("x-api-key", "<apiKey>");
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["x-api-key": "<apiKey>"]

let request = NSMutableURLRequest(url: NSURL(string: "https://api.coperniq.io/v1/invoices")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "GET"
request.allHTTPHeaderFields = headers

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```