Merge #472

472: feat(http): Distinct app and internal error codes in the handleError function r=48d90782 a=48d90782

This PR introduces distinct error codes for the app and internal RR errors.
Errors: 
```go
roadrunner.ErrNoAssociatedPool
roadrunner.ErrAllocateWorker
roadrunner.ErrWorkerNotReady
roadrunner.ErrEmptyPayload
roadrunner.ErrPoolStopped
roadrunner.ErrWorkerAllocateTimeout
roadrunner.ErrAllWorkersAreDead
```
now associated with the internal error codes. All other errors are application errors.
Some types of errors are impossible to distinguish in the RR1, for example `json.Unmarshall` internal error or similar.
The `.rr.yaml` now contain two more options for the errors.
```yaml
http:
    internalErrorCode: 502,
    appErrorCode: 502
```
Default behavior unchanged (500 error code as before), but now might be overridden.
closes #471 

Co-authored-by: Valery Piashchynski <[email protected]>

4 files changed, 13 insertions, 11 deletions

diff --git a/service/static/config.go b/service/static/config.go
index 3ca20a83..db50c7dd 100644
--- a/service/static/config.go
+++ b/service/static/config.go
@@ -2,10 +2,11 @@ package static
 
 import (
 	"fmt"
-	"github.com/spiral/roadrunner/service"
 	"os"
 	"path"
 	"strings"
+
+	"github.com/spiral/roadrunner/service"
 )
 
 // Config describes file location and controls access to them.
diff --git a/service/static/config_test.go b/service/static/config_test.go
index 8bf0d372..2bc936bb 100644
--- a/service/static/config_test.go
+++ b/service/static/config_test.go
@@ -1,10 +1,11 @@
 package static
 
 import (
+	"testing"
+
 	json "github.com/json-iterator/go"
 	"github.com/spiral/roadrunner/service"
 	"github.com/stretchr/testify/assert"
-	"testing"
 )
 
 type mockCfg struct{ cfg string }
diff --git a/service/static/service.go b/service/static/service.go
index 95b99860..49dbedab 100644
--- a/service/static/service.go
+++ b/service/static/service.go
@@ -1,9 +1,10 @@
 package static
 
 import (
-	rrhttp "github.com/spiral/roadrunner/service/http"
 	"net/http"
 	"path"
+
+	rrhttp "github.com/spiral/roadrunner/service/http"
 )
 
 // ID contains default service name.
diff --git a/service/static/service_test.go b/service/static/service_test.go
index 842662c9..bbab86c2 100644
--- a/service/static/service_test.go
+++ b/service/static/service_test.go
@@ -2,18 +2,19 @@ package static
 
 import (
 	"bytes"
-	json "github.com/json-iterator/go"
-	"github.com/sirupsen/logrus"
-	"github.com/sirupsen/logrus/hooks/test"
-	"github.com/spiral/roadrunner/service"
-	rrhttp "github.com/spiral/roadrunner/service/http"
-	"github.com/stretchr/testify/assert"
 	"io"
 	"io/ioutil"
 	"net/http"
 	"os"
 	"testing"
 	"time"
+
+	json "github.com/json-iterator/go"
+	"github.com/sirupsen/logrus"
+	"github.com/sirupsen/logrus/hooks/test"
+	"github.com/spiral/roadrunner/service"
+	rrhttp "github.com/spiral/roadrunner/service/http"
+	"github.com/stretchr/testify/assert"
 )
 
 type testCfg struct {
@@ -75,7 +76,6 @@ func Test_Files(t *testing.T) {
 
 	time.Sleep(time.Second)
 
-
 	b, _, _ := get("http://localhost:8029/sample.txt")
 	assert.Equal(t, "sample", b)
 	c.Stop()
@@ -475,7 +475,6 @@ func TestStatic_Headers(t *testing.T) {
 		t.Fatal("can't find output header in response")
 	}
 
-
 	b, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatal(err)