# Run a Process API calculation

Note: The time to run a calculation using the OLI Process API cannot be predicted accurately and also some calculations may take longer to compute than others. Hence, a polling mechanism is required to retrieve the result of each calculation. The steps for this mechanism are described below.

1. Send a **POST** request to the run URL below
2. If the request was successful(status:200), the JSON response back will contain a link to the results and status of the computation. The status inside the ***"data"*** array will be **IN QUEUE/IN PROGRESS**
3. Keep polling the returned results link with a **GET** request until the status member of the response changes from **IN PROGRESS to PROCESSED/FAILED/ERROR or COMPLETED**
4. When the status is **COMPLETED**, then response will also contain the result of the computation

###

## Run the selected process

<mark style="color:green;">`POST`</mark> `https://api.olisystems.com/process/run/{process_id}`

The input to run the calculation is provided in the body of the message as JSON, the input is  the data.flowsheet.properties object retrieved using the [get-input-specs-for-process-api-package](https://devdocs.olisystems.com/group2/get-input-specs-for-process-api-package "mention") call.

#### Headers

| Name          | Type   | Description            |
| ------------- | ------ | ---------------------- |
| Authorization | string | Bearer {access\_token} |
| Content-Type  | string | application/json       |

#### Request Body

| Name                               | Type | Description                                         |
| ---------------------------------- | ---- | --------------------------------------------------- |
| <mark style="color:red;">\*</mark> | JSON | <p>{ "properties" : { "input" " { ...}}}</p><p></p> |

{% tabs %}
{% tab title="200 " %}

```
{
	"code": 200,
	"data": {
		"file_id": "dee854a6-59db-487d-ad08-a20dee691133",
		"jobId": "f6b3375e-cd0f-4ace-a5ee-71e047b76754",
		"resultsLink": "https://api.olisystems.com/result/flash/f6b3375e-cd0f-4ace-a5ee-71e047b76754?context=engine",
		"status": "IN PROGRESS"
	},
	"message": "Process execution started Successfully",
	"status": "SUCCESS"
}
```

{% endtab %}
{% endtabs %}

### Response description

| field            | description                                                                                |
| ---------------- | ------------------------------------------------------------------------------------------ |
| data.jobId       | the current request job identifier                                                         |
| data.processId   | the processId used for the job being run                                                   |
| data.resultsLink | the https endpoint to poll to get the final result                                         |
| data.status      | <p>current status of the job<br><strong>IN QUEUE</strong>/<strong>IN PROGRESS</strong></p> |
| message          | message describing the request                                                             |
| status           | status of the current request, can be **SUCCESS** or **FAILED**                            |

```json
// Response from process-run call
{
    "data": {
        "jobId": "20978bbb-5f88-4ecd-ae90-582953afdedf",
        "processId": "a5c645fe-578b-4a48-a541-3d818d4ef564",
        "resultsLink": "https://api.olisystems.com/result/20978bbb-5f88-4ecd-ae90-582953afdedf?flash=&count=20",
        "status": "IN QUEUE"
    },
    "message": "Process execution started Successfully",
    "status": "SUCCESS"
}
```