func sendCloudFormationResponse(customResourceRequest *AbstractCustomResourceRequest,
results map[string]interface{},
responseErr error,
logger *logrus.Logger) error {
parsedURL, parsedURLErr := url.ParseRequestURI(customResourceRequest.ResponseURL)
if nil != parsedURLErr {
return parsedURLErr
}
status := "FAILED"
if nil == responseErr {
status = "SUCCESS"
}
reasonText := ""
if nil != responseErr {
reasonText = fmt.Sprintf("%s. Details in CloudWatch Logs: %s : %s",
responseErr.Error(),
customResourceRequest.LogGroupName,
customResourceRequest.LogStreamName)
} else {
reasonText = fmt.Sprintf("Details in CloudWatch Logs: %s : %s",
customResourceRequest.LogGroupName,
customResourceRequest.LogStreamName)
}
responseData := map[string]interface{}{
"Status": status,
"Reason": reasonText,
"PhysicalResourceId": customResourceRequest.PhysicalResourceID,
"StackId": customResourceRequest.StackID,
"RequestId": customResourceRequest.RequestID,
"LogicalResourceId": customResourceRequest.LogicalResourceID,
}
if nil != responseErr {
responseData["Data"] = map[string]interface{}{
"Error": responseErr,
}
} else if nil != results {
responseData["Data"] = results
} else {
responseData["Data"] = map[string]interface{}{}
}
logger.WithFields(logrus.Fields{
"ResponsePayload": responseData,
}).Debug("Response Info")
jsonData, jsonError := json.Marshal(responseData)
if nil != jsonError {
return jsonError
}
responseBuffer := strings.NewReader(string(jsonData))
req, httpErr := http.NewRequest("PUT", customResourceRequest.ResponseURL, responseBuffer)
if nil != httpErr {
return httpErr
}
// Need to use the Opaque field b/c Go will parse inline encoded values
// which are supposed to be roundtripped to AWS.
// Ref: https://tools.ietf.org/html/rfc3986#section-2.2
// Ref: https://golang.org/pkg/net/url/#URL
req.URL = &url.URL{
Scheme: parsedURL.Scheme,
Host: parsedURL.Host,
Opaque: parsedURL.RawPath,
RawQuery: parsedURL.RawQuery,
}
logger.WithFields(logrus.Fields{
"URL": req.URL,
}).Debug("Created URL response")
// Although it seems reasonable to set the Content-Type to "application/json" - don't.
// The Content-Type must be an empty string in order for the
// AWS Signature checker to pass.
// Ref: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-lambda-function-code.html
req.Header.Set("Content-Type", "")
client := &http.Client{}
resp, httpErr := client.Do(req)
if httpErr != nil {
return httpErr
}
logger.WithFields(logrus.Fields{
"LogicalResourceId": customResourceRequest.LogicalResourceID,
"Result": responseData["Status"],
"ResponseStatusCode": resp.StatusCode,
}).Info("Sent CloudFormation response")
if resp.StatusCode < 200 || resp.StatusCode > 299 {
body, bodyErr := ioutil.ReadAll(resp.Body)
if bodyErr != nil {
logger.Warn("Unable to read body: " + bodyErr.Error())
body = []byte{}
}
return fmt.Errorf("Error sending response: %d. Data: %s", resp.StatusCode, string(body))
}
defer resp.Body.Close()
return nil
}