Orchard has a REST API that follows [OpenAPI specification](https://swagger.io/specification/) and is described in [`api/openapi.yaml`](https://github.com/cirruslabs/orchard/blob/main/api/openapi.yaml).

You can run `orchard dev` locally and navigate to `http://127.0.0.1:6120/v1/` for interactive documentation.

![](../assets/images/orchard/orchard-api-documentation-browser.png)

## Using the API

Below you'll find examples of using Orchard API via vanilla Python's request library and Golang package that Orchard CLI build on top of.

### Authentication

When running in non-development mode, Orchard API expects a [basic access authentication](https://en.wikipedia.org/wiki/Basic_access_authentication) to be provided for each API call.

Below you'll find two snippets that retrieve controller's information and output its version:

#### Authentication in Python

```python
import requests
from requests.auth import HTTPBasicAuth


def main():
  # Authentication
  basic_auth = HTTPBasicAuth("service account name", "service account token")

  response = requests.get("http://127.0.0.1:6120/v1/info", auth=basic_auth)

  print(response.json()["version"])


if __name__ == '__main__':
  main()
```

#### Authentication in Golang

```go
package main

import (
  "context"
  "fmt"
  "github.com/cirruslabs/orchard/pkg/client"
  "log"
)

func main() {
  client, err := client.New()
  if err != nil {
    log.Fatalf("failed to initialize Orchard API client: %v", err)
  }

  controllerInfo, err := client.Controller().Info(context.Background())
  if err != nil {
    log.Fatalf("failed to retrieve controller's information: %v", err)
  }

  fmt.Println(controllerInfo.Version)
}
```

Note that we don't provide any credentials for Golang's version of the snippet: this is because Orchard's Golang API client (`github.com/cirruslabs/orchard/pkg/client`) has the ability to read the current's user Orchard context automatically.

### Creating a VM

A more intricate example would be spinning off a VM with a startup script that outputs date, reading its logs and removing it from the controller:

#### Creating a VM in Python

```python
import time
import uuid

import requests
from requests.auth import HTTPBasicAuth


def main():
  vm_name = str(uuid.uuid4())

  basic_auth = HTTPBasicAuth("service account name", "service account token")

  # Create VM
  response = requests.post("http://127.0.0.1:6120/v1/vms", auth=basic_auth, json={
    "name": vm_name,
    "image": "ghcr.io/cirruslabs/macos-sequoia-base:latest",
    "cpu": 4,
    "memory": 4096,
    "startup_script": {
      "script_content": "date",
    }
  })
  response.raise_for_status()

  # Retrieve VM's logs
  while True:
    response = requests.get(f"http://127.0.0.1:6120/v1/vms/{vm_name}/events", auth=basic_auth)
    response.raise_for_status()

    result = response.json()

    if isinstance(result, list) and len(result) != 0:
      print(result[0]["payload"])
      break

    time.sleep(1)

  # Delete VM
  response = requests.delete(f"http://127.0.0.1:6120/v1/vms/{vm_name}", auth=basic_auth)
  response.raise_for_status()


if __name__ == '__main__':
  main()
```

#### Creating a VM in Golang

```go
package main

import (
  "context"
  "fmt"
  "github.com/cirruslabs/orchard/pkg/client"
  v1 "github.com/cirruslabs/orchard/pkg/resource/v1"
  "github.com/google/uuid"
  "log"
  "time"
)

func main() {
  vmName := uuid.New().String()

  client, err := client.New()
  if err != nil {
    log.Fatalf("failed to initialize Orchard API client: %v", err)
  }

  // Create VM
  err = client.VMs().Create(context.Background(), &v1.VM{
    Meta: v1.Meta{
      Name: vmName,
    },
    Image:  "ghcr.io/cirruslabs/macos-sequoia-base:latest",
    CPU:    4,
    Memory: 4096,
    StartupScript: &v1.VMScript{
      ScriptContent: "date",
    },
  })
  if err != nil {
    log.Fatalf("failed to create VM: %v")
  }

  // Retrieve VM's logs
  for {
    vmLogs, err := client.VMs().Logs(context.Background(), vmName)
    if err != nil {
      log.Fatalf("failed to retrieve VM logs")
    }

    if len(vmLogs) != 0 {
      fmt.Println(vmLogs[0])
      break
    }

    time.Sleep(time.Second)
  }

  // Delete VM
  if err := client.VMs().Delete(context.Background(), vmName); err != nil {
    log.Fatalf("failed to delete VM: %v", err)
  }
}
```

## Resource management

Some resources, such as `Worker` and `VM`, have a `resource` field which is a dictionary that maps between resource names and their amounts (amount requested or amount provided, depending on the resource) and is useful for scheduling.

Well-known resources:

* `org.cirruslabs.tart-vms` — number of Tart VM slots available on the machine or requested by the VM
    * this number is `2` for workers and `1` for VMs by default
