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# PM · Deps · Add a BLOCKS, RELATES_TO, or DUPLICATES dependency between two tasks

POST https://api.simplified.com/api/v1/pm/tasks/{task_id}/add_dependency
Content-Type: application/json

Create a dependency relationship between two tasks.
Required fields: `target_task_id` (UUID of the other task), `relation_type`
(must be UPPERCASE): `BLOCKS`, `RELATES_TO`, or `DUPLICATES`.
Use `getTaskDependencies` to read the current dependency graph before adding,
to avoid duplicates. Returns the created relationship object.


Reference: https://docs.simplified.com/api-reference/project-manager/dependencies/add-task-dependency

## Authentication

- `Authorization` header (required) (prefixed with ` Api-Key   `) — Header authentication of the form `Api-Key  <token>`
- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Path parameters

- `task_id` (string, required)

### Headers

- `Organization` (string, optional) — Workspace (organization) ID the request is scoped to.
- `Space` (string, optional) — Optional sub-space ID for further scoping inside the workspace.

### Body (application/json)

This endpoint expects an AddDependencyRequest.

- `target_task_id` (string, required)
- `relation_type` (enum, optional, default: BLOCKS)
  - Allowed values: `BLOCKS`, `RELATES_TO`, `DUPLICATES`

## Response

### 201

Relationship created.

- `any`

## Examples

**Request**

```json
{
  "target_task_id": "string"
}
```

**SDK Code**

```python
import requests

url = "https://api.simplified.com/api/v1/pm/tasks/task_id/add_dependency"

payload = { "target_task_id": "string" }
headers = {
    "Authorization": "Api-Key  <apiKey>",
    "Content-Type": "application/json"
}

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

print(response.json())
```

```javascript
const url = 'https://api.simplified.com/api/v1/pm/tasks/task_id/add_dependency';
const options = {
  method: 'POST',
  headers: {Authorization: 'Api-Key  <apiKey>', 'Content-Type': 'application/json'},
  body: '{"target_task_id":"string"}'
};

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.simplified.com/api/v1/pm/tasks/task_id/add_dependency"

	payload := strings.NewReader("{\n  \"target_task_id\": \"string\"\n}")

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

	req.Header.Add("Authorization", "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.simplified.com/api/v1/pm/tasks/task_id/add_dependency")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Api-Key  <apiKey>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"target_task_id\": \"string\"\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.simplified.com/api/v1/pm/tasks/task_id/add_dependency")
  .header("Authorization", "Api-Key  <apiKey>")
  .header("Content-Type", "application/json")
  .body("{\n  \"target_task_id\": \"string\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.simplified.com/api/v1/pm/tasks/task_id/add_dependency', [
  'body' => '{
  "target_task_id": "string"
}',
  'headers' => [
    'Authorization' => 'Api-Key  <apiKey>',
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://api.simplified.com/api/v1/pm/tasks/task_id/add_dependency");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Api-Key  <apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"target_task_id\": \"string\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Api-Key  <apiKey>",
  "Content-Type": "application/json"
]
let parameters = ["target_task_id": "string"] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "https://api.simplified.com/api/v1/pm/tasks/task_id/add_dependency")! 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()
```