Merge pull request #96 in STORAGEOS/c2-cli from feature/CP-4409-cli-a…

…llow-http-500-response-for-get-diagnostics to master

Squashed commit of the following:

commit 5c316295f95d0b9807448a6604f8849430d2a64c
Author: Dom <[email protected]>
Date:   Thu Aug 13 15:28:49 2020 +0100

    cmd/get/diagnostics: print newlines around warning

    Makes it a little easier to spot

commit d42b0309efee845cacdee07e24b6c7ed2fe6d135
Author: Dom <[email protected]>
Date:   Thu Aug 13 15:28:27 2020 +0100

    apiclient/openapi: handle 502 instead of 500

commit f1b785fb2317efc5b50b617d9eb8eca29178ff0c
Author: Fraser Savage <[email protected]>
Date:   Wed Aug 12 13:50:23 2020 +0100

    Update lint rule

commit f0647eb3ba0fdb4027425be2694c914bf9dadf81
Author: Fraser Savage <[email protected]>
Date:   Wed Aug 12 13:40:32 2020 +0100

    diagnostics: Accept 500 as a potential partial bundle if we cannot get a sensible error out

.golangci.yml

@@ -73,6 +73,9 @@ issues:
     - linters:
         - gosec
       text: "G304: Potential file inclusion via variable"
+    - linters:
+        - gosec
+      text: 'G307: Deferring unsafe method "\*os\.File" on type "Close"'
 
     - path: mock_.+\.go
       text: "should have comment or be unexported"

apiclient/errors.go

@@ -1,6 +1,9 @@
 package apiclient
 
-import "fmt"
+import (
+	"fmt"
+	"io"
+)
 
 // AuthenticationError indicates that the requested operation could not be
 // performed for the client due to an issue with the authentication credentials
@@ -194,3 +197,25 @@ func NewEncodingError(err error, targetType, value interface{}) EncodingError {
 		value:      value,
 	}
 }
+
+// IncompleteDiagnosticsError provides an error type
+type IncompleteDiagnosticsError struct {
+	bundleData io.ReadCloser
+}
+
+func (e IncompleteDiagnosticsError) Error() string {
+	return "received an incomplete diagnostic bundle"
+}
+
+// BundleData returns the read closer for the bundle data associated with the error.
+func (e IncompleteDiagnosticsError) BundleData() io.ReadCloser {
+	return e.bundleData
+}
+
+// NewIncompleteDiagnosticsError constructs an incomplete diagnostics error for
+// the provided bundle data.
+func NewIncompleteDiagnosticsError(bundleData io.ReadCloser) IncompleteDiagnosticsError {
+	return IncompleteDiagnosticsError{
+		bundleData: bundleData,
+	}
+}

apiclient/openapi/diagnostics.go

@@ -7,6 +7,7 @@ import (
 	"io/ioutil"
 	"net/http"
 
+	"code.storageos.net/storageos/c2-cli/apiclient"
 	"code.storageos.net/storageos/openapi"
 )
 
@@ -40,8 +41,19 @@ func (o *OpenAPI) GetDiagnostics(ctx context.Context) (io.ReadCloser, error) {
 	}
 
 	switch resp.StatusCode {
-	case 200:
+	case http.StatusOK:
 		// Carry on.
+	case http.StatusBadGateway:
+		// Check if the response content-type indicates a partial bundle. That
+		// is, it has a gzip content type.
+		for _, value := range resp.Header["Content-Type"] {
+			if value == "application/gzip" {
+				return nil, apiclient.NewIncompleteDiagnosticsError(resp.Body)
+			}
+		}
+
+		// If not, use the normal error handling code.
+		fallthrough
 	default:
 		defer resp.Body.Close()
 		// Try to read the response body and unmarshal it into an openapi.Error

cmd/get/diagnostics.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/spf13/cobra"
 
+	"code.storageos.net/storageos/c2-cli/apiclient"
 	"code.storageos.net/storageos/c2-cli/cmd/runwrappers"
 	"code.storageos.net/storageos/c2-cli/pkg/cmdcontext"
 )
@@ -53,9 +54,19 @@ func (c *diagnosticsCommand) runWithCtx(ctx context.Context, cmd *cobra.Command,
 
 	bundle, err := c.client.GetDiagnostics(ctx)
 	if err != nil {
-		// If we failed to get a bundle then remove the file we created.
-		os.Remove(outputfile.Name())
-		return err
+		switch v := err.(type) {
+
+		case apiclient.IncompleteDiagnosticsError:
+			// If the error is for an incomplete diagnostic bundle, extract
+			// the data and warn the user.
+			bundle = v.BundleData()
+			fmt.Fprintf(os.Stderr, "\nWarning: %v\n\n", v)
+
+		default:
+			// If we failed to get a bundle at all then remove the file we created.
+			os.Remove(outputfile.Name())
+			return err
+		}
 	}
 	defer bundle.Close()