diff --git a/watchdog/README.md b/watchdog/README.md
index 0b0e44ef9a483f7b7fec0383a4423a33c978c3ba..c152fa52d140984bd26c7dd7ee7e3774d2dbc9c6 100644
--- a/watchdog/README.md
+++ b/watchdog/README.md
@@ -71,16 +71,16 @@ The watchdog can be configured through environmental variables. You must always
| Option | Usage |
|------------------------|--------------|
-| `fprocess` | The process to invoke for each function call (function process). This must be a UNIX binary and accept input via STDIN and output via STDOUT. |
-| `cgi_headers` | HTTP headers from request are made available through environmental variables - `Http_X_Served_By` etc. See section: *Handling headers* for more detail. Enabled by default. |
+| `fprocess` | The process to invoke for each function call (function process). This must be a UNIX binary and accept input via STDIN and output via STDOUT |
+| `cgi_headers` | HTTP headers from request are made available through environmental variables - `Http_X_Served_By` etc. See section: *Handling headers* for more detail. Enabled by default |
| `marshal_request` | Instead of re-directing the raw HTTP body into your fprocess, it will first be marshalled into JSON. Use this if you need to work with HTTP headers and do not want to use environmental variables via the `cgi_headers` flag. |
-| `content_type` | Force a specific Content-Type response for all responses. |
+| `content_type` | Force a specific Content-Type response for all responses |
| `write_timeout` | HTTP timeout for writing a response body from your function (in seconds) |
| `read_timeout` | HTTP timeout for reading the payload from the client caller (in seconds) |
| `suppress_lock` | The watchdog will attempt to write a lockfile to /tmp/ for swarm healthchecks - set this to true to disable behaviour. |
-| `exec_timeout` | Hard timeout for process exec'd for each incoming request (in seconds). Disabled if set to 0. |
-| `write_debug` | Write all output, error messages, and additional information to the logs. Default is false. |
-
+| `exec_timeout` | Hard timeout for process exec'd for each incoming request (in seconds). Disabled if set to 0 |
+| `write_debug` | Write all output, error messages, and additional information to the logs. Default is false |
+| `combine_output` | True by default - combines stdout/stderr in function response, when set to false `stderr` is written to the container logs and stdout is used for function response |
## Advanced / tuning
diff --git a/watchdog/main.go b/watchdog/main.go
index b13acc9b43d205bb9143233ac649424f5b1583fc..a3ac15a5fe0dd2f7177a84390b48b25412f19474 100644
--- a/watchdog/main.go
+++ b/watchdog/main.go
@@ -133,11 +133,27 @@ func pipeRequest(config *WatchdogConfig, w http.ResponseWriter, r *http.Request,
writer.Close()
}()
- // Read the output from stdout/stderr and combine into one variable for output.
- go func() {
- defer wg.Done()
- out, err = targetCmd.CombinedOutput()
- }()
+ if config.combineOutput {
+ // Read the output from stdout/stderr and combine into one variable for output.
+ go func() {
+ defer wg.Done()
+
+ out, err = targetCmd.CombinedOutput()
+ }()
+ } else {
+ go func() {
+ var b bytes.Buffer
+ targetCmd.Stderr = &b
+
+ defer wg.Done()
+
+ out, err = targetCmd.Output()
+ if b.Len() > 0 {
+ log.Printf("stderr: %s", b.Bytes())
+ }
+ b.Reset()
+ }()
+ }
wg.Wait()
if timer != nil {
@@ -181,9 +197,9 @@ func pipeRequest(config *WatchdogConfig, w http.ResponseWriter, r *http.Request,
}
}
- execTime := time.Since(startTime).Seconds()
+ execDuration := time.Since(startTime).Seconds()
if ri.headerWritten == false {
- w.Header().Set("X-Duration-Seconds", fmt.Sprintf("%f", execTime))
+ w.Header().Set("X-Duration-Seconds", fmt.Sprintf("%f", execDuration))
ri.headerWritten = true
w.WriteHeader(200)
w.Write(out)
@@ -195,9 +211,9 @@ func pipeRequest(config *WatchdogConfig, w http.ResponseWriter, r *http.Request,
}
if len(bytesWritten) > 0 {
- log.Printf("%s - Duration: %f seconds", bytesWritten, execTime)
+ log.Printf("%s - Duration: %f seconds", bytesWritten, execDuration)
} else {
- log.Printf("Duration: %f seconds", execTime)
+ log.Printf("Duration: %f seconds", execDuration)
}
}
diff --git a/watchdog/readconfig.go b/watchdog/readconfig.go
index b4cc73554403e7ae1fdb33eee2e93a729791367d..d8a1f760a36611a146e6d001640272efb9e1294a 100644
--- a/watchdog/readconfig.go
+++ b/watchdog/readconfig.go
@@ -57,8 +57,9 @@ func parseIntValue(val string, fallback int) int {
// Read fetches config from environmental variables.
func (ReadConfig) Read(hasEnv HasEnv) WatchdogConfig {
cfg := WatchdogConfig{
- writeDebug: false,
- cgiHeaders: true,
+ writeDebug: false,
+ cgiHeaders: true,
+ combineOutput: true,
}
cfg.faasProcess = hasEnv.Getenv("fprocess")
@@ -86,6 +87,10 @@ func (ReadConfig) Read(hasEnv HasEnv) WatchdogConfig {
cfg.contentType = hasEnv.Getenv("content_type")
+ if isBoolValueSet("combine_output") {
+ cfg.combineOutput = parseBoolValue(hasEnv.Getenv("combine_output"))
+ }
+
return cfg
}
@@ -124,4 +129,7 @@ type WatchdogConfig struct {
// port for HTTP server
port int
+
+ // combineOutput combines stderr and stdout in response
+ combineOutput bool
}
diff --git a/watchdog/requesthandler_test.go b/watchdog/requesthandler_test.go
index f5cbfa7a4c78a11072ce10d6ff91bac42448f2d5..da9fd96d1e4a2be5a9c3cc08cbb595e0ea3048b4 100644
--- a/watchdog/requesthandler_test.go
+++ b/watchdog/requesthandler_test.go
@@ -7,8 +7,10 @@ import (
"bytes"
"fmt"
"io/ioutil"
+ "log"
"net/http"
"net/http/httptest"
+ "os"
"strings"
"testing"
"time"
@@ -101,6 +103,96 @@ func TestHandler_HasCustomHeaderInFunction_WithCgiMode_AndBody(t *testing.T) {
}
}
+func TestHandler_StderrWritesToStderr_CombinedOutput_False(t *testing.T) {
+ rr := httptest.NewRecorder()
+
+ b := bytes.NewBuffer([]byte{})
+ log.SetOutput(b)
+
+ body := ""
+ req, err := http.NewRequest("POST", "/", bytes.NewBufferString(body))
+
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ config := WatchdogConfig{
+ faasProcess: "man badtopic",
+ cgiHeaders: true,
+ combineOutput: false,
+ }
+
+ handler := makeRequestHandler(&config)
+ handler(rr, req)
+
+ required := http.StatusInternalServerError
+
+ if status := rr.Code; status != required {
+ t.Errorf("handler returned wrong status code - got: %v, want: %v",
+ status, required)
+ }
+
+ log.SetOutput(os.Stderr)
+
+ stderrBytes, _ := ioutil.ReadAll(b)
+ stderrVal := string(stderrBytes)
+
+ if strings.Contains(stderrVal, "No manual entry for") == false {
+ t.Logf("Stderr should have contained error from function \"No manual entry for\", but was: %s", stderrVal)
+ t.Fail()
+ }
+}
+
+func TestHandler_StderrWritesToResponse_CombinedOutput_True(t *testing.T) {
+ rr := httptest.NewRecorder()
+
+ b := bytes.NewBuffer([]byte{})
+ log.SetOutput(b)
+
+ body := ""
+ req, err := http.NewRequest("POST", "/", bytes.NewBufferString(body))
+
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ config := WatchdogConfig{
+ faasProcess: "man badtopic",
+ cgiHeaders: true,
+ combineOutput: true,
+ }
+
+ handler := makeRequestHandler(&config)
+ handler(rr, req)
+
+ required := http.StatusInternalServerError
+
+ if status := rr.Code; status != required {
+ t.Errorf("handler returned wrong status code - got: %v, want: %v",
+ status, required)
+ }
+
+ log.SetOutput(os.Stderr)
+
+ stderrBytes, _ := ioutil.ReadAll(b)
+ stderrVal := string(stderrBytes)
+
+ if strings.Contains(stderrVal, "No manual entry for") {
+ t.Logf("stderr should have not included any function errors, but did")
+ t.Fail()
+ }
+
+ bodyBytes, _ := ioutil.ReadAll(rr.Body)
+ bodyStr := string(bodyBytes)
+ want := `exit status 1
+No manual entry for badtopic`
+ if strings.Contains(bodyStr, want) == false {
+ t.Logf("response want: %s, got: %s", want, bodyStr)
+ t.Fail()
+ }
+
+}
+
func TestHandler_DoesntHaveCustomHeaderInFunction_WithoutCgi_Mode(t *testing.T) {
rr := httptest.NewRecorder()