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# Render a template

POST https://mandrillapp.com/api/1.4/templates/render
Content-Type: application/json

Injects content and merge variables into a template, returning the HTML that results.

Reference: https://mailchimp.com/developer/transactional/api/templates/render

## Request

### Body (application/json)

This endpoint expects a TemplatesRenderRequest.

- `key` (string, required) — A valid Mandrill API key
- `template_name` (string, required) — Immutable name or slug of a template that exists in the user's account
- `template_content` (list of TemplateContent, required) — Array of template content to render
- `merge_vars` (list of MergeVar, optional, nullable) — Optional merge variables to use for injecting merge field content

## Response

### 200

Success

- `html` (string, required) — Rendered HTML as a string with content and merge variables injected

## Errors

### 401 Unauthorized Error

Invalid or missing API key.

- `status` (string, required) — Status of the response, typically "error"
- `code` (enum, required) — Numeric error code
  - Allowed values: `401`
- `name` (enum, required) — Machine-friendly error name
  - Allowed values: `Invalid_Key`
- `message` (string, required) — Human-readable error message

### 404 Not Found Error

Template not found

- `status` (string, required) — Status of the response, typically "error"
- `code` (integer, required) — Numeric error code
- `name` (string, required) — Machine-friendly error name
- `message` (string, required) — Human-readable error message

### 500 Internal Server Error

An unexpected internal server error occurred.

- `status` (string, required) — Status of the response, typically "error"
- `code` (integer, required) — Numeric error code
- `name` (string, required) — Machine-friendly error name
- `message` (string, required) — Human-readable error message

## Types

### TemplateContent

Content injection for template editable regions. Fields are optional to allow empty objects.

- `name` (string, optional, nullable) — Name of the mc:edit editable region to inject into
- `content` (string, optional, nullable) — Content to inject into the editable region

### MergeVar

Merge variable for template content injection

- `name` (string, optional) — Merge variable name (case-insensitive, may not start with _)
- `content` (string, optional) — Content value for the merge variable

## Examples

**Request**

```json
{
  "key": "ONzNrsmbtNXoIKyfPmjnig",
  "template_name": "example-template",
  "template_content": [
    {
      "name": "editable",
      "content": "content"
    }
  ],
  "merge_vars": [
    {
      "name": "merge1",
      "content": "merge1 content"
    }
  ]
}
```

**Response**

```json
{
  "html": "<div>Rendered template content with merge variables</div>"
}
```

**SDK Code**

```python
import requests

url = "https://mandrillapp.com/api/1.4/templates/render"

payload = {
    "key": "ONzNrsmbtNXoIKyfPmjnig",
    "template_name": "example-template",
    "template_content": [
        {
            "name": "editable",
            "content": "content"
        }
    ],
    "merge_vars": [
        {
            "name": "merge1",
            "content": "merge1 content"
        }
    ]
}
headers = {"Content-Type": "application/json"}

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

print(response.json())
```

```javascript
const url = 'https://mandrillapp.com/api/1.4/templates/render';
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: '{"key":"ONzNrsmbtNXoIKyfPmjnig","template_name":"example-template","template_content":[{"name":"editable","content":"content"}],"merge_vars":[{"name":"merge1","content":"merge1 content"}]}'
};

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://mandrillapp.com/api/1.4/templates/render"

	payload := strings.NewReader("{\n  \"key\": \"ONzNrsmbtNXoIKyfPmjnig\",\n  \"template_name\": \"example-template\",\n  \"template_content\": [\n    {\n      \"name\": \"editable\",\n      \"content\": \"content\"\n    }\n  ],\n  \"merge_vars\": [\n    {\n      \"name\": \"merge1\",\n      \"content\": \"merge1 content\"\n    }\n  ]\n}")

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

	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://mandrillapp.com/api/1.4/templates/render")

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

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"key\": \"ONzNrsmbtNXoIKyfPmjnig\",\n  \"template_name\": \"example-template\",\n  \"template_content\": [\n    {\n      \"name\": \"editable\",\n      \"content\": \"content\"\n    }\n  ],\n  \"merge_vars\": [\n    {\n      \"name\": \"merge1\",\n      \"content\": \"merge1 content\"\n    }\n  ]\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://mandrillapp.com/api/1.4/templates/render")
  .header("Content-Type", "application/json")
  .body("{\n  \"key\": \"ONzNrsmbtNXoIKyfPmjnig\",\n  \"template_name\": \"example-template\",\n  \"template_content\": [\n    {\n      \"name\": \"editable\",\n      \"content\": \"content\"\n    }\n  ],\n  \"merge_vars\": [\n    {\n      \"name\": \"merge1\",\n      \"content\": \"merge1 content\"\n    }\n  ]\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://mandrillapp.com/api/1.4/templates/render', [
  'body' => '{
  "key": "ONzNrsmbtNXoIKyfPmjnig",
  "template_name": "example-template",
  "template_content": [
    {
      "name": "editable",
      "content": "content"
    }
  ],
  "merge_vars": [
    {
      "name": "merge1",
      "content": "merge1 content"
    }
  ]
}',
  'headers' => [
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://mandrillapp.com/api/1.4/templates/render");
var request = new RestRequest(Method.POST);
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"key\": \"ONzNrsmbtNXoIKyfPmjnig\",\n  \"template_name\": \"example-template\",\n  \"template_content\": [\n    {\n      \"name\": \"editable\",\n      \"content\": \"content\"\n    }\n  ],\n  \"merge_vars\": [\n    {\n      \"name\": \"merge1\",\n      \"content\": \"merge1 content\"\n    }\n  ]\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["Content-Type": "application/json"]
let parameters = [
  "key": "ONzNrsmbtNXoIKyfPmjnig",
  "template_name": "example-template",
  "template_content": [
    [
      "name": "editable",
      "content": "content"
    ]
  ],
  "merge_vars": [
    [
      "name": "merge1",
      "content": "merge1 content"
    ]
  ]
] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "https://mandrillapp.com/api/1.4/templates/render")! 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()
```