Openwhisk Client Go

This project openwhisk-client-go is a Go client library to access Openwhisk API.

Prerequisites

You need to install the following package in order to run this Go client library:

Go
govendor

Make sure you select the package that fits your local environment, and set the GOPATH environment variable.

Installation

After you download the source code either from the Github or the release page of OpenWhisk, you should have a directory named openwhisk-client-go to host all the source code. Please copy this root directory openwhisk-client-go into the directory $GOPATH/src/github.com/apache.

Test

Open a terminal, and run the following commands to run the unit tests:

$ cd $GOPATH/src/github.com/apache/openwhisk-client-go
$ govendor sync
$ go test -v ./... -tags=unit

You should see all the unit tests passed. If not, please log an issue for us.

Configuration

This Go client library is used to access the OpenWhisk API, so please make sure you have an OpenWhisk service running somewhere available for you to run this library.

We use a configuration file called wskprop to specify all the parameters necessary for this Go client library to access the OpenWhisk services. Make sure you create or edit the file ~/.wskprops, and add the mandatory parameters APIHOST, APIVERSION, NAMESPACE and AUTH.

The parameter APIHOST is the OpenWhisk API hostname (for example, openwhisk.ng.bluemix.net, 172.17.0.1, and so on). The parameter APIVERSION is the version of OpenWhisk API to be used to access the OpenWhisk resources. The parameter NAMESPACE is the OpenWhisk namespace used to specify the OpenWhisk resources about to be accessed. The parameter AUTH is the authentication key used to authenticate the incoming requests to the OpenWhisk services.

For more information regarding the REST API of OpenWhisk, please refer to OpenWhisk REST API.

Usage

import "github.com/apache/openwhisk-client-go/whisk"

Construct a new whisk client, then use various services to access different parts of the whisk api. For example to get the hello action:

client, _ := whisk.NewClient(http.DefaultClient, nil)
action, resp, err := client.Actions.List("hello")

Some API methods have optional parameters that can be passed. For example, to list the first 30 actions, after the 30th action:

client, _ := whisk.NewClient(http.DefaultClient, nil)

options := &whisk.ActionListOptions{
  Limit: 30,
  Skip: 30,
}

actions, resp, err := client.Actions.List(options)

By default, this Go client library is automatically configured by the configuration file wskprop. The parameters of APIHOST, APIVERSION, NAMESPACE and AUTH will be used to access the OpenWhisk services.

In addition, it can also be configured by passing in a *whisk.Config object as the second argument to whisk.New( ... ). For example:

config := &whisk.Config{
  Host: "openwhisk.ng.bluemix.net",
  Version: "v1"
  Namespace: "_",
  AuthKey: "aaaaa-bbbbb-ccccc-ddddd-eeeee"
}
client, err := whisk.Newclient(http.DefaultClient, config)

Example

You need to have an OpenWhisk service accessible, to run the following example.

Please be advised that all the Go files you are about to create should be under the directory of $GOPATH or its subdirectories. For example, create the Go file named openwhisk_client_go.go under a directory called $GOPATH/src/example to try the following code.

import (
  "net/http"
  "net/url"

  "github.com/apache/openwhisk-client-go/whisk"
)

func main() {
  client, err := whisk.NewClient(http.DefaultClient, nil)
  if err != nil {
    fmt.Println(err)
    os.Exit(-1)
  }

  options := &whisk.ActionListOptions{
    Limit: 30,
    Skip: 30,
  }

  actions, resp, err := client.Actions.List(options)
  if err != nil {
    fmt.Println(err)
    os.Exit(-1)
  }

  fmt.Println("Returned with status: ", resp.Status)
  fmt.Println("Returned actions: \n%+v", actions)

}

Then build it with the go tool:

$ cd $GOPATH/src/example
$ go build

The command above will build an executable named client in the directory alongside your source code. Execute it to see the the result:

$ ./openwhisk_client_go

If the openWhisk service is available and your configuration is correct, you should receive the status and the actions with the above example.