To import the library:
import "github.com/pulse/vtm"
To connect directly to a Virtual Traffic Manager instance:
trafficManager := vtm.NewVirtualTrafficManager("https://vtm1:9070/api", "admin", "P@55w0rD!")
To connect to a Virtual Traffic Manager instance via a Services Director proxy:
trafficManager := vtm.NewVirtualTrafficManager("https://sd1:8100/api/tmcm/2.5/instance/vtm1", "sd_admin", "SD_P@55w0rD!")
Some resources, for example global settings, occur as single occurrences. These resources support the Get<ResourceType> function and the <Instance>.Apply() method. NB. values are stored with pointers.
globalSettings, err := trafficManager.GetGlobalSettings()
*globalSettings.Connection.IdleTimeout = 22
*globalSettings.FaultTolerance.AutoFailback = false
globalSettings.Apply()
NB. settings will not be applied until the Apply() method is called.
Most resource types, for example pools, virtual servers and TrafficScript rules, have many instances. These resources support the List<ResourceType>s, Get<ResourceType>, New<ResourceType> and Delete<ResourceType> functions.
To get a list of the names of each instance of a configuration object:
vsList, err := trafficManager.ListVirtualServers()
for _, vsName := range vsList {
fmt.Println("Virtual server: ", vsName)
}
To get a specific instance of a configuration object we use the Get<ResourceType> function. This applies to both JSON-based and text-based resources:
myVs, err := trafficManager.GetVirtualServer("my_virtual_server")
myRule, err := trafficManager.GetRule("my_trafficscript_rule")
Some configuration objects are data structures (ie. JSON-based in the API) whilst some are text-based. Get<ResourceType>() calls return structures or strings respectively.
For JSON-based objects (NB. values are stored with pointers):
fmt.Println("Virtual server port: ", *myVs.Basic.Port)
fmt.Println("Virtual server default pool: ", *myVs.Basic.Pool)
For text-based object:
fmt.Printf("My TrafficScript Rule: \n%v\n", myRule)
JSON-based and text-based resources have different methods for altering their data. JSON-based resources can have their field values changed locally, and then with a call to the <Instance>.Apply() method, the changes are applied to the vTM:
*myVs.Basic.Port = 443
*myVs.WebCache.Enabled = true
myVs.Apply()
As text-based resources are a single piece of data, they use the Set<ResourceType> function to either create a new or overwrite an existing resource:
err := trafficManager.SetRule("my_trafficscript_rule", "log.info('I overwrote an existing rule');")
err := trafficManager.SetRule("new_rule", "log.info('I created a new rule');")
Creating new text-based objects was shown in the previous section (using the Set<ResourceType> function). Creating JSON-based objects is done using the New<ResourceType> functions. Depending on the resource type, initialization parameters may be required (see the function signatures or the REST API manual). *NOTE: the New<ResourceType>
To create a new instance of a configuration object with initialization parameters (in this case, the default pool and the listen port, as required to create a virtual server resource):
newVs, err := trafficManager.NewVirtualServer("new_virtual_server", "discard", 8080)
To create a new instance of an object that does not require initialization parameters:
newPool, err := trafficManager.NewPool("new_pool")
To delete a specific instance of a configuration object (same for JSON- and text-based objects):
err := trafficManager.DeleteVirtualServer("new_virtual_server")
err := trafficManager.DeleteRule("new_rule")
Virtual Traffic Manager provides many read-only counters and statistics. These can be accessed using the Get<Resource>Statistics functions.
Functions for stats on single-occurrence objects take no arguments:
globalStats, err := trafficManager.GetGlobalsStatistics()
fmt.Printf("Data memory usage: %d\n", globalStats.DataMemoryUsage)
fmt.Printf("Uptime: %d\n", globalStats.UpTime)
Functions for stats on multiple-occurrence objects take an object name as the only argument:
vsStats, err := trafficManager.GetVirtualServersStatistics("my_vs")
fmt.Printf("Bytes In: %d\n", vsStats.BytesIn)
fmt.Printf("Bytes Out: %d\n", vsStats.BytesOut)
Virtual Traffic Manger provides some resources containing current statuses:
vtmState, err := trafficManager.GetSystemState()
for _, vtmError := range vtmState.State.Errors {
fmt.Printf("Error: %s\n", vtmError)
}
vtmInformation, err := trafficManager.GetSystemInformation()
fmt.Printf("vTM UUID: %s\n", vtmInformation.Information.Uuid)
All functions/methods will return a pointer to an error as either their second or only return value. If this is a nil pointer, no error occurred. If not, an error object will be available:
myVs, err := trafficManager.GetVirtualServer("my_non_existent_vs")
if err != nil {
fmt.Println("ErrorId: ", err.ErrorId)
fmt.Println("ErrorText: ", err.ErrorText)
fmt.Println("ErrorInfo: ", err.ErrorInfo)
}
would result in:
ErrorId: resource.not_found
ErrorText: Resource '/api/tm/5.0/config/active/virtual_servers/my_non_existent_vs' does not exist
ErrorInfo:
Note that the ErrorInfo field is only populated in the case of particular errors; often it is empty.
Copyright © 2018, Pulse Secure LLC. Licensed under the terms of the MPL 2.0. See the LICENSE file for details.