cloud

Cisco pxGrid Cloud SDK for Go

Overview

cloud-sdk-go is the Cisco pxGrid Cloud SDK for the Go programming language. This SDK requires a minimum version of Go 1.18.

The SDK lets you easily create applications for Cisco pxGrid Cloud and consume pxGrid, ERS and OpenAPI services from Cisco Identity Services Engine (ISE) devices.

Features

• Multi-tenancy support
• Create an instance of an application
• Link application with a Cisco DNA - Cloud tenant
• Receive pxGrid topic messages from Cisco ISE devices
• Invoke HTTP APIs on Cisco ISE devices
  • pxGrid APIs
  • ERS APIs
  • OpenAPI APIs

Install

go get github.com/cisco-pxgrid/cloud-sdk-go

Usage

Examples

Create a new app instance

import (
    "fmt"
    sdk "github.com/cisco-pxgrid/cloud-sdk-go"
)

// activationHandler is invoked when the app gets activated for a new device for a tenant
func activationHandler(device *sdk.Device) {
    fmt.Printf("New device activated: %s\n", device)
}

// deactivationHandler is invoked when the app gets deactivated for an existing device for a tenant
func deactivationHandler(device *sdk.Device) {
    fmt.Printf("Device deactivated: %s\n", device)
}

// messageHandler is invoked when there's a new message received by the app for a device
func messageHandler(id string, device *sdk.Device, stream string, payload []byte) {
    fmt.Printf("Received new message (%s) from %s\n", id, device)
    fmt.Printf("Message stream: %s\n", stream)
    fmt.Printf("Message payload: %s\n", payload)
}

// getCredentials is invoked whenever the app needs to retrieve the app credentials
func getCredentials() (*sdk.Credentials, error) {
    return &sdk.Credentials{
        ApiKey: []byte("api-key-obtained-during-app-onboarding"),
    }, nil
}

func main() {
    // create app configuration required for creating a new app instance
    config := sdk.Config{
        ID:                        "pxgrid-cloud-sample-app",
        GetCredentials:            getCredentials,
        RegionalFQDN:              "regional.cloud.cisco.com",
        GlobalFQDN:                "global.cloud.cisco.com",
        DeviceActivationHandler:   activationHandler,
        DeviceDeactivationHandler: deactivationHandler,
        DeviceMessageHandler:      messageHandler,
        ReadStreamID:              "app--pxgrid-cloud-sample-app-R",
        WriteStreamID:             "app--pxgrid-cloud-sample-app-W",
    }

   	app, err := sdk.New(config)
    if err != nil {
        fmt.Printf("Failed to create new app: %v", err)
        os.Exit(1)
    }
    // make sure to Close() the app instance to release resources acquired during app creation
    defer func() {
        if err := app.Close(); err != nil {
            fmt.Printf("Disconnected with error: %v", err)
        }
    }()

    // wait for any errors from the app instance created above
    err = <- app.Error
    if err != nil {
        fmt.Printf("%s received an error: %v", app, err)
    }
}

Link and unlink with a tenant

tenant, err := app.LinkTenant("otp-obtained-from-cisco-dna-portal")
if err != nil {
    fmt.Printf("Failed to obtain tenant information using supplied OTP: %v", err)
}

// Securely store tenant.ID(), tenant.Name() and tenant.ApiToken()

err = app.UnlinkTenant(tenant)
if err != nil {
    fmt.Printf("Failed to unlink %s from %s: %v", tenant, app, err)
}

Setup already linked tenants

If the app needs to be restarted, use the stored tenant info to re-link.

tenant, err := app.SetTenant("tenant-id", "tenant-name", "tenant-api-token")
if err != nil {
    fmt.Printf("Failed to set tenant: %v", err)
}

Create app instances

If the app is registered as multi-instance, create and delete app instances can be used.

// With the parent app object, create an app instance
appInstance, err = app.CreateAppInstance(ac.Name)

// Securely store appInstance.ID(), appInstance.ApiKey()

// appInstance can then be used to LinkTenant
tenant, err = appInstance.LinkTenant("otp-obtained-from-cisco-dna-portal")

// When finish, delete app instance with parent app
app.DeleteAppInstance(appInstance.ID())

Invoke an ERS or OpenAPI HTTP API call on a device

ERS and OpenAPI URLs start with "/ers" and "/api" respectively.

API guide and reference

req, _ := http.NewRequest(http.MethodGet, "/ers/config/op/systemconfig/iseversion", nil)
resp, err := device.Query(req)
if err != nil {
    fmt.Printf("Failed to invoke %s on %s: %v", req, device, err)
}

Invoke pxGrid HTTP API on a device

pxGrid Reference

In order to invoke pxGrid APIs directly on the device, ServiceLookup is not required. Instead map the service name to the keyword and append it to the URL along with pxgrid

req, _ := http.NewRequest(http.MethodPost, "/pxgrid/trustsec/getSecurityGroups", strings.NewReader("{}"))
resp, err := device.Query(req)
if err != nil {
    fmt.Printf("Failed to invoke %s on %s: %v", req, device, err)
}

Query limitation

There is currently a limitation on the payload size

Stream names mappings

These are the mappings of pxGrid Cloud stream names from pxGrid topic

Terminology

• App: An app represents an application that's available on the Cisco DNA - Cloud App Store.
• Tenant: A tenant represents a Cisco customer that subscribes to and intends to use services Cisco DNA - Cloud services.
• Device: A device represents an on-premise entity (an appliance, a VM, a deployment, a cluster, etc.) that is registered with the Cisco DNA - Cloud. Cisco ISE is such an example.