search: add support for streaming search (#485)

This adds the flag `-stream` to the `search` sub-command. Searches
submitted with `-stream` are routed to the endpoint `search/stream`
instead of the GraphQL API.

In addition, users can set `-display <int>` to set the display limit.

We will add support for JSON in a follow-up PR.

Author: stefanhengl

cmd/src/format.go

@@ -60,6 +60,9 @@ func parseTemplate(text string) (*template.Template, error) {
 		"addFloat": func(x, y float64) float64 {
 			return x + y
 		},
+		"addInt32": func(x, y int32) int32 {
+			return x + y
+		},
 		"debug": func(v interface{}) string {
 			data, _ := marshalIndent(v)
 			fmt.Println(string(data))
@@ -91,6 +94,13 @@ func parseTemplate(text string) (*template.Template, error) {
 		"buildVersionHasNewSearchInterface": searchTemplateFuncs["buildVersionHasNewSearchInterface"],
 		"renderResult":                      searchTemplateFuncs["renderResult"],
 
+		// Register stream-search specific template functions.
+		"streamSearchSequentialLineNumber": streamSearchTemplateFuncs["streamSearchSequentialLineNumber"],
+		"streamSearchHighlightMatch":       streamSearchTemplateFuncs["streamSearchHighlightMatch"],
+		"streamSearchHighlightCommit":      streamSearchTemplateFuncs["streamSearchHighlightCommit"],
+		"streamSearchRenderCommitLabel":    streamSearchTemplateFuncs["streamSearchRenderCommitLabel"],
+		"matchOrMatches":                   streamSearchTemplateFuncs["matchOrMatches"],
+
 		// Alert rendering
 		"searchAlertRender": func(alert searchResultsAlert) string {
 			if content, err := alert.Render(); err != nil {

cmd/src/search.go

@@ -17,6 +17,7 @@ import (
 
 	isatty "github.com/mattn/go-isatty"
 	"github.com/sourcegraph/src-cli/internal/api"
+	"github.com/sourcegraph/src-cli/internal/streaming"
 	"jaytaylor.com/html2text"
 )
 
@@ -50,17 +51,28 @@ Other tips:
 
 	flagSet := flag.NewFlagSet("search", flag.ExitOnError)
 	var (
-		jsonFlag        = flagSet.Bool("json", false, "Whether or not to output results as JSON")
+		jsonFlag        = flagSet.Bool("json", false, "Whether or not to output results as JSON.")
 		explainJSONFlag = flagSet.Bool("explain-json", false, "Explain the JSON output schema and exit.")
 		apiFlags        = api.NewFlags(flagSet)
-		lessFlag        = flagSet.Bool("less", true, "Pipe output to 'less -R' (only if stdout is terminal, and not json flag)")
+		lessFlag        = flagSet.Bool("less", true, "Pipe output to 'less -R' (only if stdout is terminal, and not json flag).")
+		streamFlag      = flagSet.Bool("stream", false, "Consume results as stream. Streaming search only supports a subset of flags and parameters: trace, insecure-skip-verify, display.")
+		display         = flagSet.Int("display", -1, "Limit the number of results that are displayed. Only supported together with stream flag. Statistics continue to report all results.")
 	)
 
 	handler := func(args []string) error {
 		if err := flagSet.Parse(args); err != nil {
 			return err
 		}
 
+		if *streamFlag {
+			opts := streaming.Opts{
+				Display: *display,
+				Trace:   apiFlags.Trace(),
+			}
+			client := cfg.apiClient(apiFlags, flagSet.Output())
+			return streamSearch(flagSet.Arg(0), opts, client, os.Stdout)
+		}
+
 		if *explainJSONFlag {
 			fmt.Println(searchJSONExplanation)
 			return nil

cmd/src/search_alert.go

@@ -19,15 +19,18 @@ func init() {
 	}
 }
 
+// ProposedQuery is a suggested query to run when we emit an alert.
+type ProposedQuery struct {
+	Description string
+	Query       string
+}
+
 // searchResultsAlert is a type that can be used to unmarshal values returned by
 // the searchResultsAlertFragment GraphQL fragment below.
 type searchResultsAlert struct {
 	Title           string
 	Description     string
-	ProposedQueries []struct {
-		Description string
-		Query       string
-	}
+	ProposedQueries []ProposedQuery
 }
 
 // Render renders an alert to a string ready to be output to a console,

cmd/src/search_alert_test.go

@@ -13,10 +13,7 @@ func TestRender(t *testing.T) {
 	full := &searchResultsAlert{
 		Title:       "foo",
 		Description: "bar",
-		ProposedQueries: []struct {
-			Description string
-			Query       string
-		}{
+		ProposedQueries: []ProposedQuery{
 			{
 				Description: "quux",
 				Query:       "xyz:abc",