> For the complete documentation index, see [llms.txt](https://docs.navigaglobal.com/writer/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.navigaglobal.com/writer/6.4.1/developer-guide/tutorials/integrating-external-spell-checking.md).

# Integrating External Spell Checking

## Writer Configuration

In order to enable the spellcheck integration, the Writer's server-config needs to be edited. The following should be added to your server-config's `external`-config object:

```
"spellcheck": {
    "check": {
        "url": "[your-spellcheck-endpoint]",
        "headers": {
            "x-foo": "bar"
        }
    },
    "suggestion": {
        "url": "[your-suggestion-endpoint]",
        "headers": {
            "x-foo": "bar"
        }
    }
}
```

### Field Description

| Field                                    | Description                                                                                      |
| ---------------------------------------- | ------------------------------------------------------------------------------------------------ |
| `external.spellcheck`                    | Contains the configuration for external spellchecking endpoints.                                 |
| `external.spellcheck.check`              | **Optional** Object containing configuration for external spellcheck requests.                   |
| `external.spellcheck.check.url`          | **Required** Full url and path to your check request implementation.                             |
| `external.spellcheck.check.headers`      | **Optional** Key-value object with extra header's which will be used in the request to your API. |
| `external.spellcheck.suggestion`         | **Optional** Object containing configuration for external suggestion requests.                   |
| `external.spellcheck.suggestion.url`     | **Required** Full url and path to your suggestion request implementation.                        |
| `external.spellcheck.suggestion.headers` | **Optional** Key-value object with extra header's which will be used in the request to your API. |

The `headers`-properties are useful if you need to send additional headers to your API.

{% hint style="warning" %}
Remember, the writer service needs to be restarted for server config changes to take effect
{% endhint %}

## External API Specification

Your API needs to be able to handle the following requests to integrate with spell checking and suggestion.

### Language Codes

Language codes from the writer are sent in the format `[language-identifier]_[region_identifier]`. Where `[language-identifier]` follows the [ISO 639-1](https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes) standard, which is two letters, lowercased. The `[region-identifier]` follows the [ISO 3166-2](https://en.wikipedia.org/wiki/ISO_3166-2) standard, which is two letters, uppercased.

Examples: `sv_SE`, `en_GB`, `en_US`, `nl_NL`

### Spellcheck Request

The API must be able to receive the following request on an endpoint you define:

#### **Request**

```
    POST [your-spellcheck-endpoint]
    headers
        Accept: application/json
        Content-Type: application/json 
    body
        {
            "lang": "sv_SE",
            "words": [
                { "start": 0, "end": 5, "text": "Lorem" },
                { "start": 6, "end": 11, "text": "ipsum" },
                { "start": 12, "end": 17, "text": "dolor" },
                { "start": 18, "end": 21, "text": "sit" },
                { "start": 22, "end": 26, "text": "amet" },
                { "start": 28, "end": 39, "text": "consectetur" },
                { "start": 40, "end": 50, "text": "adipiscing" },
                { "start": 51, "end": 55, "text": "elit" },
                { "start": 57, "end": 60, "text": "sed" },
                { "start": 61, "end": 63, "text": "do" },
                { "start": 64, "end": 71, "text": "eiusmod" },
                { "start": 72, "end": 78, "text": "tempor" }
            ]
        }
```

#### **Response**

The API should respond with a single array containing the misspelled words in the same json-format as they were sent, if no words were misspelled, response should contain an empty array.

**Response Format**

```
headers
    Content-Type: application/json 
body
    [
      { "start": 0, "end": 5, "text": "Lorem" },
      { "start": 6, "end": 11, "text": "ipsum" },
      { "start": 12, "end": 17, "text": "dolor" },
      { "start": 61, "end": 63, "text": "do" },
      { "start": 64, "end": 71, "text": "eiusmod" }
    ]
```

**Example Request**

The API should be able to perform the call below, and output an array of the misspelled words, or an empty array.

```
fetch("[your-spellcheck-endpoint]", {
    method: 'post',
    headers: {'Accept': 'application/json', 'Content-Type': 'application/json'},
    body: JSON.stringify({
        "lang": "[language_code]",
        "words": [
            { "start": 0, "end": 5, "text": "Lorem" },
            { "start": 6, "end": 11, "text": "ipsum" },
            { "start": 12, "end": 17, "text": "dolor" },
            { "start": 61, "end": 63, "text": "do" },
            { "start": 64, "end": 71, "text": "eiusmod" }
        ]
    })
})
    .then((res) => res.json())
    .then((json) => console.log(json))
```

Output:

```
    [
        {"start":0,"end":5,"text":"Lorem"},
        {"start":6,"end":11,"text":"ipsum"},
        {"start":64,"end":71,"text":"eiusmod"}
    ]
```

#### Suggestions

The API must be able to receive the following request on an endpoint you define:

**Request**

```
    POST [your-suggestion-endpoint]
    headers
        Accept: application/json
        Content-Type: application/json
    URL Params
        word=String
        lang=[language_code]
```

**Response**

The API should respond with a single array containing the misspelled words in the same json-format as they were sent, if no words were misspelled, response should be an empty array.

**Response Format**

```
    headers
        Content-Type: application/json
    body
        [
            "tempot",
            "tempo",
            "tempon",
            "tempos",
            "teorem"
        ]
```

**Example Request**

The API should be able to perform the call below, and output an array of words, or an empty array.

```javascript
fetch("[your-suggestion-endpoint]?word=tempor&lang=en_US", {
    headers: {'Accept': 'application/json', 'Content-Type': 'application/json'}
})
    .then((res) => res.json())
    .then((json) => console.log(json))
```

Output

```javascript
["tempo", "temper", "tempos", "temp or", "temp-or", "tempo r"]
```