From 49ec565a044568ccf27e2f20102e00a6cd29b856 Mon Sep 17 00:00:00 2001
From: Peter Bourgon <peter@bourgon.org>
Date: Tue, 16 Jun 2015 10:42:40 +0200
Subject: [PATCH] Improve error messages during report validation

---
 .gitignore         |  1 +
 report/topology.go | 44 ++++++++++++++++++++++++++++----------------
 xfer/collector.go  |  2 +-
 3 files changed, 30 insertions(+), 17 deletions(-)

diff --git a/.gitignore b/.gitignore
index e14a70224..f5472e787 100644
--- a/.gitignore
+++ b/.gitignore
@@ -40,6 +40,7 @@ docker/probe
 experimental/bridge/bridge
 experimental/demoprobe/demoprobe
 experimental/fixprobe/fixprobe
+experimental/fixprobe/*.json
 experimental/genreport/genreport
 experimental/graphviz/graphviz
 experimental/oneshot/oneshot
diff --git a/report/topology.go b/report/topology.go
index 544102f74..13c85e1ed 100644
--- a/report/topology.go
+++ b/report/topology.go
@@ -5,6 +5,7 @@ import (
 	"log"
 	"net"
 	"reflect"
+	"strings"
 )
 
 const localUnknown = "localUnknown"
@@ -274,43 +275,54 @@ func (r ByID) Less(i, j int) bool { return r[i].ID < r[j].ID }
 
 // Validate checks the topology for various inconsistencies.
 func (t Topology) Validate() error {
-	// Check all edge metadata keys must have the appropriate entries in adjacencies & node metadata
+	// Check all edge metadata keys must have the appropriate entries in
+	// adjacencies & node metadata.
+	var errs []string
 	for edgeID := range t.EdgeMetadatas {
 		srcNodeID, dstNodeID, ok := ParseEdgeID(edgeID)
 		if !ok {
-			return fmt.Errorf("Invalid edge id: %s", edgeID)
+			errs = append(errs, fmt.Sprintf("invalid edge ID %q", edgeID))
+			continue
 		}
 		if _, ok := t.NodeMetadatas[srcNodeID]; !ok {
-			return fmt.Errorf("Source node missing for edge id: %s", edgeID)
+			errs = append(errs, fmt.Sprintf("node metadata missing for source node ID %q (from edge %q)", srcNodeID, edgeID))
+			continue
 		}
-
-		adjs, ok := t.Adjacency[MakeAdjacencyID(srcNodeID)]
+		dstNodeIDs, ok := t.Adjacency[MakeAdjacencyID(srcNodeID)]
 		if !ok {
-			return fmt.Errorf("Adjancey entries for missing for node id: %s (from edge %s)", srcNodeID, edgeID)
+			errs = append(errs, fmt.Sprintf("adjacency entries missing for source node ID %q (from edge %q)", srcNodeID, edgeID))
+			continue
 		}
-		if !adjs.Contains(dstNodeID) {
-			return fmt.Errorf("Adjancey entry missing for edge id: %s", edgeID)
+		if !dstNodeIDs.Contains(dstNodeID) {
+			errs = append(errs, fmt.Sprintf("adjacency destination missing for destination node ID %q (from edge %q)", dstNodeID, edgeID))
+			continue
 		}
 	}
 
-	// Check all adjancency keys has entries in NodeMetadata
-	for adjID := range t.Adjacency {
-		nodeID, ok := ParseAdjacencyID(adjID)
+	// Check all adjancency keys has entries in NodeMetadata.
+	for adjacencyID := range t.Adjacency {
+		nodeID, ok := ParseAdjacencyID(adjacencyID)
 		if !ok {
-			return fmt.Errorf("Invalid adjacency id: %s", adjID)
+			errs = append(errs, fmt.Sprintf("invalid adjacency ID %q", adjacencyID))
+			continue
 		}
-
 		if _, ok := t.NodeMetadatas[nodeID]; !ok {
-			return fmt.Errorf("Source node missing for adjancency id: %s", adjID)
+			errs = append(errs, fmt.Sprintf("node metadata missing for source node %q (from adjacency %q)", nodeID, adjacencyID))
+			continue
 		}
 	}
 
-	// Check all node metadata keys are parse-able (ie, contain a scope)
+	// Check all node metadata keys are parse-able (i.e. contain a scope)
 	for nodeID := range t.NodeMetadatas {
 		if _, _, ok := ParseNodeID(nodeID); !ok {
-			return fmt.Errorf("Invalid node id: %s", nodeID)
+			errs = append(errs, fmt.Sprintf("invalid node ID %q", nodeID))
+			continue
 		}
 	}
 
+	if len(errs) > 0 {
+		return fmt.Errorf(strings.Join(errs, "; "))
+	}
+
 	return nil
 }
diff --git a/xfer/collector.go b/xfer/collector.go
index 464d8e8fe..9333ee106 100644
--- a/xfer/collector.go
+++ b/xfer/collector.go
@@ -103,7 +103,7 @@ func (c *realCollector) loop(batchTime time.Duration) {
 
 		case r := <-c.in:
 			if err := r.Validate(); err != nil {
-				log.Printf("Received invalid report from: %v", err)
+				log.Printf("Received invalid report: %v", err)
 				continue
 			}
 			current.Merge(r)