Review feedback - adding plugin status field

common/xfer/plugin_spec.go

@@ -25,6 +25,8 @@ type PluginSpec struct {
 
 	// Interfaces is a list of things this plugin can be used for (e.g. "reporter")
 	Interfaces []string `json:"interfaces"`
+
+	Status string `json:"status,omitempty"`
 }
 
 // PluginSpecs is a set of plugin specs keyed on ID. Clients must use

probe/plugins/registry.go

@@ -171,6 +171,24 @@ func (r *Registry) Implementers(iface string, f func(p *Plugin)) {
 	})
 }
 
+// Name implements the Reporter interface
+func (r *Registry) Name() string { return "plugins" }
+
+// Report implements the Reporter interface
+func (r *Registry) Report() (report.Report, error) {
+	rpt := report.MakeReport()
+	r.Implementers("reporter", func(plugin *Plugin) {
+		pluginReport, err := plugin.Report()
+		if err != nil {
+			log.Errorf("plugins: error getting report from %s: %v", plugin.ID, err)
+			pluginReport = report.MakeReport()
+		}
+		pluginReport.Plugins = pluginReport.Plugins.Add(plugin.PluginSpec)
+		rpt = rpt.Merge(pluginReport)
+	})
+	return rpt, nil
+}
+
 // Close shuts down the registry. It can still be used after this, but will be
 // out of date.
 func (r *Registry) Close() {
@@ -219,7 +237,8 @@ type handshakeResponse struct {
 
 // handshake tries the handshake with this plugin.
 func (p *Plugin) handshake(ctx context.Context, expectedAPIVersion string, params url.Values) func() (bool, error) {
-	return func() (bool, error) {
+	return func() (ok bool, err error) {
+		defer func() { p.setStatus(err) }()
 		var resp handshakeResponse
 		if err := p.get("/", params, &resp); err != nil {
 			return err == context.Canceled, fmt.Errorf("plugins: error loading plugin %s: %v", p.socket, err)
@@ -243,9 +262,18 @@ func (p *Plugin) handshake(ctx context.Context, expectedAPIVersion string, param
 func (p *Plugin) Report() (report.Report, error) {
 	result := report.MakeReport()
 	err := p.get("/report", nil, &result)
+	p.setStatus(err)
 	return result, err
 }
 
+func (p *Plugin) setStatus(err error) {
+	if err == nil {
+		p.Status = "ok"
+	} else {
+		p.Status = fmt.Sprintf("error: %v", err)
+	}
+}
+
 // TODO(paulbellamy): better error handling on wrong status codes
 func (p *Plugin) get(path string, params url.Values, result interface{}) error {
 	ctx, cancel := context.WithTimeout(p.context, pluginTimeout)

probe/plugins/reporter.go

@@ -1,25 +0,0 @@
-package plugins
-
-import (
-	log "github.com/Sirupsen/logrus"
-
-	"github.com/weaveworks/scope/probe"
-	"github.com/weaveworks/scope/report"
-)
-
-// Reporter implements the Reporter interface for a plugin registry.
-func Reporter(pluginRegistry *Registry) probe.Reporter {
-	return probe.ReporterFunc("plugins", func() (report.Report, error) {
-		rpt := report.MakeReport()
-		pluginRegistry.Implementers("reporter", func(plugin *Plugin) {
-			pluginReport, err := plugin.Report()
-			if err != nil {
-				log.Errorf("plugins: error getting report from %s: %v", plugin.ID, err)
-				return
-			}
-			pluginReport.Plugins = pluginReport.Plugins.Add(plugin.PluginSpec)
-			rpt = rpt.Merge(pluginReport)
-		})
-		return rpt, nil
-	})
-}

prog/probe.go

@@ -206,7 +206,7 @@ func probeMain() {
 		}
 	}
 
-	p.AddReporter(plugins.Reporter(pluginRegistry))
+	p.AddReporter(pluginRegistry)
 
 	if *httpListen != "" {
 		go func() {