From 2d48f3a029611d79d664238895ec84a900d2470e Mon Sep 17 00:00:00 2001
From: Michael Marineau <michael.marineau@coreos.com>
Date: Thu, 8 Jun 2017 14:28:48 -0700
Subject: [PATCH] client: send error events if update check or ping fails

Does not report errors when sending events since that would be cyclic.
---
 omaha/client/client.go | 20 +++++++++++++++++---
 omaha/client/error.go  | 36 +++++++++++++++++++++++++++++++++---
 omaha/client/http.go   |  9 ++++-----
 3 files changed, 54 insertions(+), 11 deletions(-)

diff --git a/omaha/client/client.go b/omaha/client/client.go
index 8e287e3..61c25cd 100644
--- a/omaha/client/client.go
+++ b/omaha/client/client.go
@@ -209,11 +209,16 @@ func (ac *AppClient) UpdateCheck() (*omaha.UpdateResponse, error) {
 	ac.sentPing = true
 
 	appResp, err := ac.doReq(ac.apiEndpoint, req)
-	if err != nil {
+	if err, ok := err.(ErrorEvent); ok {
+		ac.Event(err.ErrorEvent())
+		return nil, err
+	} else if err != nil {
+		ac.Event(NewErrorEvent(ExitCodeOmahaRequestError))
 		return nil, err
 	}
 
 	if appResp.Ping == nil {
+		ac.Event(NewErrorEvent(ExitCodeOmahaResponseInvalid))
 		return nil, fmt.Errorf("omaha: ping status missing from response")
 	}
 
@@ -222,6 +227,7 @@ func (ac *AppClient) UpdateCheck() (*omaha.UpdateResponse, error) {
 	}
 
 	if appResp.UpdateCheck == nil {
+		ac.Event(NewErrorEvent(ExitCodeOmahaResponseInvalid))
 		return nil, fmt.Errorf("omaha: update check missing from response")
 	}
 
@@ -240,11 +246,16 @@ func (ac *AppClient) Ping() error {
 	ac.sentPing = true
 
 	appResp, err := ac.doReq(ac.apiEndpoint, req)
-	if err != nil {
+	if err, ok := err.(ErrorEvent); ok {
+		ac.Event(err.ErrorEvent())
+		return err
+	} else if err != nil {
+		ac.Event(NewErrorEvent(ExitCodeOmahaRequestError))
 		return err
 	}
 
 	if appResp.Ping == nil {
+		ac.Event(NewErrorEvent(ExitCodeOmahaResponseInvalid))
 		return fmt.Errorf("omaha: ping status missing from response")
 	}
 
@@ -325,7 +336,10 @@ func (ac *AppClient) doReq(url string, req *omaha.Request) (*omaha.AppResponse,
 
 	appResp := resp.GetApp(appID)
 	if appResp == nil {
-		return nil, fmt.Errorf("omaha: app %s missing from response", appID)
+		return nil, &omahaError{
+			Err:  fmt.Errorf("app %s missing from response", appID),
+			Code: ExitCodeOmahaResponseInvalid,
+		}
 	}
 
 	if appResp.Status != omaha.AppOK {
diff --git a/omaha/client/error.go b/omaha/client/error.go
index 9e1a80e..cf221a2 100644
--- a/omaha/client/error.go
+++ b/omaha/client/error.go
@@ -21,11 +21,19 @@ import (
 	"net"
 	"net/http"
 	"time"
+
+	"github.com/coreos/go-omaha/omaha"
 )
 
 var (
-	bodySizeError  = errors.New("http response exceeded 1MB")
-	bodyEmptyError = errors.New("http response was empty")
+	bodySizeError = &omahaError{
+		Err:  errors.New("http response exceeded 1MB"),
+		Code: ExitCodeOmahaResponseInvalid,
+	}
+	bodyEmptyError = &omahaError{
+		Err:  errors.New("http response was empty"),
+		Code: ExitCodeOmahaRequestEmptyResponseError,
+	}
 
 	// default parameters for expNetBackoff
 	backoffStart = time.Second
@@ -60,7 +68,21 @@ func isUnexpectedEOF(err error) bool {
 	return err == io.ErrUnexpectedEOF
 }
 
-// httpError implements error and net.Error for http responses.
+// omahaError implements error and ErrorEvent for omaha requests/responses.
+type omahaError struct {
+	Err  error
+	Code ExitCode
+}
+
+func (oe *omahaError) Error() string {
+	return "omaha: request failed: " + oe.Err.Error()
+}
+
+func (oe *omahaError) ErrorEvent() *omaha.EventRequest {
+	return NewErrorEvent(oe.Code)
+}
+
+// httpError implements error, net.Error, and ErrorEvent for http responses.
 type httpError struct {
 	*http.Response
 }
@@ -69,6 +91,14 @@ func (he *httpError) Error() string {
 	return "http error: " + he.Status
 }
 
+func (he *httpError) ErrorEvent() *omaha.EventRequest {
+	code := ExitCodeOmahaRequestError
+	if he.StatusCode > 0 && he.StatusCode < 1000 {
+		code = ExitCodeOmahaRequestHTTPResponseBase + ExitCode(he.StatusCode)
+	}
+	return NewErrorEvent(code)
+}
+
 func (he *httpError) Timeout() bool {
 	switch he.StatusCode {
 	case http.StatusRequestTimeout: // 408
diff --git a/omaha/client/http.go b/omaha/client/http.go
index 13e4a7b..9a634b7 100644
--- a/omaha/client/http.go
+++ b/omaha/client/http.go
@@ -45,7 +45,7 @@ func newHTTPClient() *httpClient {
 func (hc *httpClient) doPost(url string, reqBody []byte) (*omaha.Response, error) {
 	resp, err := hc.Post(url, "text/xml; charset=utf-8", bytes.NewReader(reqBody))
 	if err != nil {
-		return nil, err
+		return nil, &omahaError{err, ExitCodeOmahaRequestError}
 	}
 	defer resp.Body.Close()
 
@@ -59,6 +59,8 @@ func (hc *httpClient) doPost(url string, reqBody []byte) (*omaha.Response, error
 		err = bodySizeError
 	} else if err == io.EOF {
 		err = bodyEmptyError
+	} else if err != nil {
+		err = &omahaError{err, ExitCodeOmahaRequestXMLParseError}
 	}
 
 	// Prefer reporting HTTP errors over XML parsing errors.
@@ -81,9 +83,6 @@ func (hc *httpClient) Omaha(url string, req *omaha.Request) (resp *omaha.Respons
 		resp, err = hc.doPost(url, buf.Bytes())
 		return err
 	})
-	if err != nil {
-		return nil, fmt.Errorf("omaha: request failed: %v", err)
-	}
 
-	return resp, nil
+	return resp, err
 }