Adds support for passing the query as a parameter

Returns all version if no version is specified, updates snapctl help
and updates the href to use a parameter for the namespace query.

cmd/snapctl/commands.go

@@ -164,7 +164,7 @@ var (
 				},
 				{
 					Name:   "get",
-					Usage:  "get details on a single metric",
+					Usage:  "get details on metric(s)",
 					Action: getMetric,
 					Flags: []cli.Flag{
 						flMetricVersion,

cmd/snapctl/flags.go

@@ -135,7 +135,7 @@ var (
 	// metric
 	flMetricVersion = cli.IntFlag{
 		Name:  "metric-version, v",
-		Usage: "The metric version. Default (0) is latest",
+		Usage: "The metric version. 0 (default) returns all. -1 returns latest.",
 	}
 	flMetricNamespace = cli.StringFlag{
 		Name:  "metric-namespace, m",

mgmt/rest/client/metric.go

@@ -56,7 +56,7 @@ func (c *Client) GetMetricCatalog() *GetMetricsResult {
 // It returns the corresponding metric catalog if succeeded. Otherwise, an error is returned.
 func (c *Client) FetchMetrics(ns string, ver int) *GetMetricsResult {
 	r := &GetMetricsResult{}
-	q := fmt.Sprintf("/metrics%s?ver=%d", ns, ver)
+	q := fmt.Sprintf("/metrics?ns=%s&ver=%d", ns, ver)
 	resp, err := c.do("GET", q, ContentTypeJSON)
 	if err != nil {
 		return &GetMetricsResult{Err: err}
@@ -80,7 +80,7 @@ func (c *Client) FetchMetrics(ns string, ver int) *GetMetricsResult {
 // GetMetricVersions retrieves all versions of a metric at a given namespace.
 func (c *Client) GetMetricVersions(ns string) *GetMetricsResult {
 	r := &GetMetricsResult{}
-	q := fmt.Sprintf("/metrics%s", ns)
+	q := fmt.Sprintf("/metrics?ns=%s", ns)
 	resp, err := c.do("GET", q, ContentTypeJSON)
 	if err != nil {
 		return &GetMetricsResult{Err: err}
@@ -100,11 +100,12 @@ func (c *Client) GetMetricVersions(ns string) *GetMetricsResult {
 
 // GetMetric retrieves a metric at a given namespace and version.
 // If the version is < 1, the latest version is returned.
-// Now returns an interface as several return types are possible
-// (array of metrics)
+// Returns an interface as several return types are possible
+// (array of metrics).
 func (c *Client) GetMetric(ns string, ver int) interface{} {
 	r := &GetMetricResult{}
-	q := fmt.Sprintf("/metrics%s?ver=%d", ns, ver)
+
+	q := fmt.Sprintf("/metrics?ns=%s&ver=%d", ns, ver)
 	resp, err := c.do("GET", q, ContentTypeJSON)
 	if err != nil {
 		return &GetMetricResult{Err: err}

mgmt/rest/metric.go

@@ -22,8 +22,10 @@ package rest
 import (
 	"fmt"
 	"net/http"
+	"net/url"
 	"sort"
 	"strconv"
+	"strings"
 
 	"github.com/julienschmidt/httprouter"
 
@@ -32,6 +34,38 @@ import (
 )
 
 func (s *Server) getMetrics(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+	ver := 0 // 0: get all metrics
+
+	// If we are provided a parameter with the name 'ns' we need to
+	// perform a query
+	q := r.URL.Query()
+	v := q.Get("ver")
+	ns_query := q.Get("ns")
+	if ns_query != "" {
+		ver = 0 // 0: get all versions
+		if v != "" {
+			var err error
+			ver, err = strconv.Atoi(v)
+			if err != nil {
+				respond(400, rbody.FromError(err), w)
+				return
+			}
+		}
+		// strip the leading '/' and split on the remaining '/'
+		ns := strings.Split(strings.TrimLeft(ns_query, "/"), "/")
+		if ns[len(ns)-1] == "*" {
+			ns = ns[:len(ns)-1]
+		}
+
+		mets, err := s.mm.FetchMetrics(core.NewNamespace(ns...), ver)
+		if err != nil {
+			respond(404, rbody.FromError(err), w)
+			return
+		}
+		respondWithMetrics(r.Host, mets, w)
+		return
+	}
+
 	mets, err := s.mm.MetricCatalog()
 	if err != nil {
 		respond(500, rbody.FromError(err), w)
@@ -63,7 +97,7 @@ func (s *Server) getMetricsFromTree(w http.ResponseWriter, r *http.Request, para
 
 	if ns[len(ns)-1] == "*" {
 		if v == "" {
-			ver = -1
+			ver = 0 //return all metrics
 		} else {
 			ver, err = strconv.Atoi(v)
 			if err != nil {
@@ -81,14 +115,14 @@ func (s *Server) getMetricsFromTree(w http.ResponseWriter, r *http.Request, para
 		return
 	}
 
-	// If no version was given, get all that fall at this namespace.
+	// If no version was given, get all version that fall at this namespace.
 	if v == "" {
-		mts, err := s.mm.GetMetricVersions(core.NewNamespace(ns...))
+		mets, err := s.mm.FetchMetrics(core.NewNamespace(ns...), 0)
 		if err != nil {
 			respond(404, rbody.FromError(err), w)
 			return
 		}
-		respondWithMetrics(r.Host, mts, w)
+		respondWithMetrics(r.Host, mets, w)
 		return
 	}
 
@@ -175,7 +209,7 @@ func respondWithMetrics(host string, mets []core.CatalogedMetric, w http.Respons
 }
 
 func catalogedMetricURI(host string, mt core.CatalogedMetric) string {
-	return fmt.Sprintf("%s://%s/v1/metrics%s?ver=%d", protocolPrefix, host, mt.Namespace().String(), mt.Version())
+	return fmt.Sprintf("%s://%s/v1/metrics?ns=%s&ver=%d", protocolPrefix, host, url.QueryEscape(mt.Namespace().String()), mt.Version())
 }
 
 func getDynamicElements(ns core.Namespace, indexes []int) []rbody.DynamicElement {

mgmt/rest/server.go

@@ -20,6 +20,7 @@ limitations under the License.
 package rest
 
 import (
+	"bytes"
 	"crypto/tls"
 	"encoding/json"
 	"errors"
@@ -510,6 +511,7 @@ func respond(code int, b rbody.Body, w http.ResponseWriter) {
 	if err != nil {
 		panic(err)
 	}
+	j = bytes.Replace(j, []byte("\\u0026"), []byte("&"), -1)
 	fmt.Fprint(w, string(j))
 }