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# Create Invoice

POST https://api.coperniq.io/v1/invoices
Content-Type: application/json

Create a new invoice.

Required fields:
- `recordId`: Project or account ID (the record must exist first)
- `calculationMethod`: Must be "LINE_ITEMS" or "PERCENTAGE"

Conditionally required:
- `lineItems`: Required when `calculationMethod` is "LINE_ITEMS" (at least one item)
- `percentage`: Required when `calculationMethod` is "PERCENTAGE"

Optional fields:
- `issueDate`: ISO 8601 datetime string
- `dueDate`: ISO 8601 datetime string
- `status`: Initial invoice status (defaults to DRAFT)
- `description`: Invoice description


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

## Authentication

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

## Request

### Body (application/json)

This endpoint expects an InvoiceCreate.

- `recordId` (integer, required) — Project or account ID
- `calculationMethod` (enum, required) — Calculation method
  - Allowed values: `LINE_ITEMS`, `PERCENTAGE`
- `lineItems` (list of InvoiceLineItemCreate, optional) — Required when `calculationMethod` is `LINE_ITEMS` and `sections` is not provided. Flat array of line items (auto-grouped into one unnamed section).
- `sections` (list of InvoiceSection, optional) — Required when `calculationMethod` is `LINE_ITEMS` and `lineItems` is not provided. Grouped line items with named sections. May be combined with `lineItems` (ungrouped items).
- `percentage` (double, optional) — Required when `calculationMethod` is `PERCENTAGE`.
- `status` (enum, optional) — Optional; defaults to DRAFT when omitted. To finalize the invoice, set `SENT`, `PARTIALLY_PAID`, or `PAID` — `issueDate` is then required. Lifecycle statuses (DECLINED, OVERDUE) cannot be set at creation.
  - Allowed values: `DRAFT`, `SENT`, `PARTIALLY_PAID`, `PAID`
- `issueDate` (string, optional) — Issue date (ISO 8601). Optional. Applied only when `status` is SENT/PARTIALLY_PAID/PAID (required for those); ignored for DRAFT invoices.
- `dueDate` (string, optional) — Due date (ISO 8601 datetime string)
- `description` (string, optional, nullable) — Invoice description

## Response

### 201

Invoice created successfully

- `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
- `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)

## 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

### InvoiceLineItemCreate

- `catalogItemId` (integer, required) — Catalog item identifier
- `quantity` (integer, required) — Quantity
- `unitCost` (double, required) — Cost per unit
- `unitPrice` (double, required) — Price per unit (may be negative for discount line items)
- `id` (integer, optional, default: 0) — Line item ID (0 for new items)
- `description` (string, optional, nullable) — Line item description

### InvoiceSection

A named section grouping one or more invoice line items.

- `lineItems` (list of InvoiceLineItemCreate, required) — Line items within this section (at least one required)
- `id` (integer, optional) — Existing section ID (omit for new sections)
- `name` (string, optional, nullable) — Section name (1–500 chars). Omit or pass null for an unnamed section.

### 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

**Request**

```json
{
  "recordId": 1,
  "calculationMethod": "LINE_ITEMS"
}
```

**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",
  "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"

payload = {
    "recordId": 1,
    "calculationMethod": "LINE_ITEMS"
}
headers = {
    "x-api-key": "<apiKey>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://api.coperniq.io/v1/invoices';
const options = {
  method: 'POST',
  headers: {'x-api-key': '<apiKey>', 'Content-Type': 'application/json'},
  body: '{"recordId":1,"calculationMethod":"LINE_ITEMS"}'
};

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"
	"strings"
	"net/http"
	"io"
)

func main() {

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

	payload := strings.NewReader("{\n  \"recordId\": 1,\n  \"calculationMethod\": \"LINE_ITEMS\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-api-key", "<apiKey>")
	req.Header.Add("Content-Type", "application/json")

	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::Post.new(url)
request["x-api-key"] = '<apiKey>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"recordId\": 1,\n  \"calculationMethod\": \"LINE_ITEMS\"\n}"

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.post("https://api.coperniq.io/v1/invoices")
  .header("x-api-key", "<apiKey>")
  .header("Content-Type", "application/json")
  .body("{\n  \"recordId\": 1,\n  \"calculationMethod\": \"LINE_ITEMS\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.coperniq.io/v1/invoices', [
  'body' => '{
  "recordId": 1,
  "calculationMethod": "LINE_ITEMS"
}',
  'headers' => [
    'Content-Type' => 'application/json',
    '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.POST);
request.AddHeader("x-api-key", "<apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"recordId\": 1,\n  \"calculationMethod\": \"LINE_ITEMS\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "x-api-key": "<apiKey>",
  "Content-Type": "application/json"
]
let parameters = [
  "recordId": 1,
  "calculationMethod": "LINE_ITEMS"
] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

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

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()
```