Hi!
Thanks for the reply!
This plugin is being used to support sending metrics to a Wavefront proxy container in the GCP CloudRun cloud space. In order to send metrics into the proxy in this space you need to send a HTTP REST POST request with a token that has a maximum expiration time of one hour. In order to account for that I have a package that I added to Telegraf that is referenced in the plugin:
Some of that code is below
func GetToken(secret string, email string, url string) string {
token, err := generateJWT(secret, email, url, 3000)
if err != nil {
println(err.Error())
}
//fmt.Printf("Token: %s\n", token)
accessToken, err := getGoogleID(token)
if err != nil {
println(err.Error())
}
return accessToken
}
On the plugin side, I basically took most of the code from the outputs.http package but added a few extra fields to the http struct to account for the additional fields required in order to refresh the token in the above code:
type HTTP struct {
URL string `toml:"url"`
Timeout internal.Duration `toml:"timeout"`
Method string `toml:"method"`
Username string `toml:"username"`
Password string `toml:"password"`
Headers map[string]string `toml:"headers"`
ClientID string `toml:"client_id"`
ClientSecret string `toml:"client_secret"`
TokenURL string `toml:"token_url"`
Scopes []string `toml:"scopes"`
ContentEncoding string `toml:"content_encoding"`
JSONSecret string `toml:"json_file_location"`
GCPEmailAddress string `toml:"cloudrun_email"`
tls.ClientConfig
client *http.Client
serializer serializers.Serializer
}
I added some constants (not shown here) to create some defaults for the headers and then added the return of the token code (the first code block) into a variable called token and set it as a header.
token := gcp.GetToken(h.JSONSecret, h.GCPEmailAddress, h.URL)
req.Header.Set("User-Agent", internal.ProductToken())
req.Header.Set("Content-Type", defaultContentType)
req.Header.Set("Accept", defaultAccept)
req.Header.Set("Authorization = Bearer", token)
if h.ContentEncoding == "gzip" {
req.Header.Set("Content-Encoding", "gzip")
It looks like it all works:
2020-08-04T14:47:05Z D! [agent] Connecting outputs
2020-08-04T14:47:05Z D! [agent] Attempting connection to [outputs.cloudrun]
2020-08-04T14:47:05Z D! [agent] Successfully connected to outputs.cloudrun
2020-08-04T14:47:05Z D! [agent] Starting service inputs
2020-08-04T14:47:18Z D! [outputs.cloudrun] Buffer fullness: 0 / 10000 metrics
But then errors when it tries to send to the proxy because what looks like it not using a token:
2020-08-04T14:49:18Z D! [outputs.cloudrun] Buffer fullness: 27 / 10000 metrics
2020-08-04T14:49:18Z E! [agent] Error writing to outputs.cloudrun: Post https://wavefront-proxy-.run.app: net/http: invalid header field name "Authorization = Bearer"
I’m trying to figure out what might be going on by adding some logging.
Thoughts?
EDIT:
ssorka over at github gave me this information:
This is a great question, thanks!
Add this to your plugin struct, and a logger will be set automatically for it when it’s registered:
type MyPlugin {
...
Log telegraf.Logger `toml:"-"`
}
in your tests, you’ll have to set this yourself to the test logger, eg:
myplugin := &MyPlugin{}
myplugin.Log = testutil.Logger{}
Using the logger is easy, it implements the telegraf.Logger interface
For example, using it in an input’s gather function would look like this:
func (p *MyPlugin) Gather(acc telegraf.Accumulator) error {
p.Log.Debug("Starting the gather function!")
...
}
Now that that’s said, we should get that into the docs somewhere.
