nci/gsky: processor/drill_indexer.go; 138 LoC

Found a possible issue in [nci/gsky](https://www.github.com/nci/gsky) at [processor/drill_indexer.go](https://github.com/nci/gsky/blob/5dd6b599e9b0e3f1bdc1174e8b9a115a208449d1/processor/drill_indexer.go#L74-L211)

Below is the message reported by the analyzer for this snippet of code. Beware that the analyzer only reports the first
issue it finds, so please do not limit your consideration to the contents of the below message.

> range-loop variable geoReq used in defer or goroutine at line 154

[Click here to see the code in its original context.](https://github.com/nci/gsky/blob/5dd6b599e9b0e3f1bdc1174e8b9a115a208449d1/processor/drill_indexer.go#L74-L211)

Click here to show the 138 line(s) of Go which triggered the analyzer.

```go
for geoReq := range p.In {
var feat geo.Feature
err := json.Unmarshal([]byte(geoReq.Geometry), &feat)
if err != nil {
p.sendError(fmt.Errorf("Drill Indexer: Problem unmarshalling GeoJSON object: %v", geoReq.Geometry))
return
}

ns := geoReq.NameSpaces
if geoReq.Mask != nil {
for _, v := range geoReq.Mask.IDExpressions.VarList {
ns = append(ns, v)
}
}
namespaces := strings.Join(ns, ",")

reqURL := p.getRequestURL(geoReq, namespaces)
featWKT := feat.Geometry.MarshalWKT()

if isInit {
if geoReq.MetricsCollector != nil {
if len(geoReq.MetricsCollector.Info.Indexer.URL.RawURL) == 0 {
geoReq.MetricsCollector.Info.Indexer.URL.RawURL = reqURL
}

if len(geoReq.MetricsCollector.Info.Indexer.Geometry) == 0 {
geoReq.MetricsCollector.Info.Indexer.Geometry = featWKT
}

if len(geoReq.MetricsCollector.Info.Indexer.SRS) == 0 {
geoReq.MetricsCollector.Info.Indexer.SRS = geoReq.CRS
}
}

isInit = false
}

if verbose {
logRequestGeometry("Drill Indexer: original request: ", reqURL, featWKT)
}

tiledGeoms, err := getTiledGeometries(feat.Geometry.MarshalWKT(), geoReq, verbose)
if err != nil || len(tiledGeoms) == 0 {
tiledGeoms = append(tiledGeoms, featWKT)
}

if verbose && err != nil {
log.Printf("Drill Indexer: %v", err)
}

tiledResChanSize := len(tiledGeoms)
if tiledResChanSize > 100 {
tiledResChanSize = 100
}

tiledRes := make(chan *TiledResponse, tiledResChanSize)

go func() {
defer close(tiledRes)
for ig, geomWKT := range tiledGeoms {
postBody := url.Values{"wkt": {geomWKT}}
if verbose {
logRequestGeometry(fmt.Sprintf("Drill Indexer(%d/%d): ", ig+1, len(tiledGeoms)), reqURL, geomWKT)
}

start := time.Now()
resp, err := http.PostForm(reqURL, postBody)
if err != nil {
p.sendError(fmt.Errorf("Drill Indexer: POST request to %s failed. Error: %v", reqURL, err))
continue
}

body, err := ioutil.ReadAll(resp.Body)
resp.Body.Close()
if err != nil {
p.sendError(fmt.Errorf("Drill Indexer: Error parsing response body from %s. Error: %v", reqURL, err))
break
}

indexTime := time.Since(start)
if geoReq.MetricsCollector != nil {
geoReq.MetricsCollector.Info.Indexer.Duration += indexTime
}

var metadata MetadataResponse
err = json.Unmarshal(body, &metadata)
if err != nil {
fmt.Println(string(body))
p.sendError(fmt.Errorf("Drill Indexer: Problem parsing JSON response from %s. Error: %v", reqURL, err))
break
}

if len(metadata.Error) > 0 {
fmt.Printf("Drill Indexer error: %v", string(body))
p.sendError(fmt.Errorf("Drill Indexer error: %v", metadata.Error))
break
}

if p.checkCancellation() {
return
}
tiledRes <- &TiledResponse{IndexerID: ig, NumIndexers: len(tiledGeoms), IndexerTime: indexTime, Metadata: &metadata}
}
}()

var template *jet.Template
if geoReq.Mask != nil {
path := "."
view := jet.NewSet(jet.SafeWriter(func(w io.Writer, b []byte) {
w.Write(b)
}), path, "/")

template, err = view.GetTemplate(geoReq.VRTURL)
if err != nil {
log.Printf("Drill Indexer error: %v", err)
p.sendError(fmt.Errorf("Drill Indexer error: %v", err))
return
}
}

isFirst := true
dedupGranules := make(map[string]struct{})
for res := range tiledRes {
p.processDatasets(res, geoReq, template, dedupGranules, verbose, &isFirst)
if p.checkCancellation() {
break
}
}

if geoReq.MetricsCollector != nil {
geoReq.MetricsCollector.Info.Indexer.NumFiles += len(dedupGranules)
geoReq.MetricsCollector.Info.Indexer.NumGranules += len(dedupGranules)
}

if verbose {
log.Printf("Drill Indexer: total effective GDAL subdatasets: %v", len(dedupGranules))
}
}

```

Leave a reaction on this issue to contribute to the project by classifying this instance as a **Bug** :-1:, **Mitigated** :+1:, or **Desirable Behavior** :rocket:
See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: 5dd6b599e9b0e3f1bdc1174e8b9a115a208449d1