add integration test for "outfile append.."

4 files changed, 485 insertions, 9 deletions

diff --git a/integrationtests/dmap4.csv.expected b/integrationtests/dmap4.csv.expected
new file mode 100644
index 0000000..f6dc4cc
--- /dev/null
+++ b/integrationtests/dmap4.csv.expected
@@ -0,0 +1,407 @@
+count($time),$time,max($goroutines),avg($goroutines),min($goroutines)
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+2,1002-071239,11.000000,11.000000,11.000000
+2,1002-071427,11.000000,11.000000,11.000000
+2,1002-071636,11.000000,11.000000,11.000000
+2,1002-071148,11.000000,11.000000,11.000000
+2,1002-071237,11.000000,11.000000,11.000000
+2,1002-071518,11.000000,11.000000,11.000000
+2,1002-071708,11.000000,11.000000,11.000000
+2,1002-071736,11.000000,11.000000,11.000000
+2,1002-071319,11.000000,11.000000,11.000000
+2,1002-071528,11.000000,11.000000,11.000000
+2,1002-071738,11.000000,11.000000,11.000000
+2,1002-071307,11.000000,11.000000,11.000000
+2,1002-071449,11.000000,11.000000,11.000000
+2,1002-071459,11.000000,11.000000,11.000000
+2,1002-071748,11.000000,11.000000,11.000000
+2,1002-071407,11.000000,11.000000,11.000000
+2,1002-071938,11.000000,11.000000,11.000000
+2,1002-071618,11.000000,11.000000,11.000000
+2,1002-071828,11.000000,11.000000,11.000000
+2,1002-071509,11.000000,11.000000,11.000000
+2,1002-071227,11.000000,11.000000,11.000000
+2,1002-071908,11.000000,11.000000,11.000000
+2,1002-071339,11.000000,11.000000,11.000000
+2,1002-071758,11.000000,11.000000,11.000000
+2,1002-071149,11.000000,11.000000,11.000000
+2,1002-071838,11.000000,11.000000,11.000000
+2,1002-071349,11.000000,11.000000,11.000000
+2,1002-071716,11.000000,11.000000,11.000000
+2,1002-071718,11.000000,11.000000,11.000000
+2,1002-071806,11.000000,11.000000,11.000000
+2,1002-071706,11.000000,11.000000,11.000000
+2,1002-071507,11.000000,11.000000,11.000000
+2,1002-071816,11.000000,11.000000,11.000000
+2,1002-071439,11.000000,11.000000,11.000000
+2,1002-071257,11.000000,11.000000,11.000000
+2,1002-071846,11.000000,11.000000,11.000000
+2,1002-071457,11.000000,11.000000,11.000000
+2,1002-071329,11.000000,11.000000,11.000000
+2,1002-071259,11.000000,11.000000,11.000000
+1,1002-071949,15.000000,15.000000,15.000000
diff --git a/integrationtests/dmap4.csv.query.expected b/integrationtests/dmap4.csv.query.expected
new file mode 100644
index 0000000..84b37e3
--- /dev/null
+++ b/integrationtests/dmap4.csv.query.expected
@@ -0,0 +1 @@
+from STATS select count($time),$time,max($goroutines),avg($goroutines),min($goroutines) group by $time order by count($time) outfile append dmap4.csv.tmp
\ No newline at end of file
diff --git a/integrationtests/dmap_test.go b/integrationtests/dmap_test.go
index 346a872..600aaa9 100644
--- a/integrationtests/dmap_test.go
+++ b/integrationtests/dmap_test.go
@@ -189,3 +189,59 @@ func TestDMap3(t *testing.T) {
 	os.Remove(csvFile)
 	os.Remove(queryFile)
 }
+
+func TestDMap4Append(t *testing.T) {
+	if !config.Env("DTAIL_INTEGRATION_TEST_RUN_MODE") {
+		t.Log("Skipping")
+		return
+	}
+	inFile := "mapr_testdata.log"
+	outFile := "dmap4.stdout.tmp"
+	csvFile := "dmap4.csv.tmp"
+	expectedCsvFile := "dmap4.csv.expected"
+	queryFile := fmt.Sprintf("%s.query", csvFile)
+	expectedQueryFile := "dmap4.csv.query.expected"
+
+	// Delete in case it exists already. Otherwise, test will fail.
+	os.Remove(csvFile)
+
+	query := fmt.Sprintf("from STATS select count($time),$time,max($goroutines),"+
+		"avg($goroutines),min($goroutines) group by $time order by count($time) "+
+		"outfile append %s", csvFile)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// Run dmap command twice, it should append in the 2nd iteration the new results to the already existing
+	// fille as we specified "outfile append". That works transparently for any mapreduce query
+	// (e.g. also for the dtail command in streaming mode). But it is easier to test with the dmap
+	// command.
+	for i := 0; i < 2; i++ {
+		stdoutCh, stderrCh, cmdErrCh, err := startCommand(ctx, t,
+			"", "../dmap",
+			"--query", query,
+			"--cfg", "none",
+			"--logger", "stdout",
+			"--logLevel", "info",
+			"--noColor", inFile)
+
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		waitForCommand(ctx, t, stdoutCh, stderrCh, cmdErrCh)
+	}
+
+	if err := compareFilesContents(t, csvFile, expectedCsvFile); err != nil {
+		t.Error(err)
+		return
+	}
+	if err := compareFiles(t, queryFile, expectedQueryFile); err != nil {
+		t.Error(err)
+		return
+	}
+
+	os.Remove(outFile)
+	os.Remove(csvFile)
+	os.Remove(queryFile)
+}
diff --git a/internal/mapr/groupsetresult.go b/internal/mapr/groupsetresult.go
index 40c10fe..4b86025 100644
--- a/internal/mapr/groupsetresult.go
+++ b/internal/mapr/groupsetresult.go
@@ -187,13 +187,23 @@ func (g *GroupSet) WriteResult(query *Query) error {
 		return err
 	}
 
+	// By default, also write the CSV header.
+	writeHeader := true
+
+	// In append mode, only write CSV header when file doesn't exist yet or is empty.
+	if query.Outfile.AppendMode {
+		if info, err := os.Stat(query.Outfile.FilePath); err == nil && info.Size() > 0 {
+			writeHeader = false
+		}
+	}
+
 	fd, err := g.getOutfileFD(query)
 	if err != nil {
 		return err
 	}
 	defer fd.Close()
 
-	return g.resultWriteUnformatted(query, rows, fd)
+	return g.resultWriteUnformatted(query, rows, fd, writeHeader)
 }
 
 func (g *GroupSet) getOutfileFD(query *Query) (*os.File, error) {
@@ -208,17 +218,19 @@ func (g *GroupSet) getOutfileFD(query *Query) (*os.File, error) {
 	return os.OpenFile(query.Outfile.FilePath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
 }
 
-func (g *GroupSet) resultWriteUnformatted(query *Query, rows []result, fd *os.File) error {
-	// Generate header now
+func (g *GroupSet) resultWriteUnformatted(query *Query, rows []result, fd *os.File, writeHeader bool) error {
 	lastColumn := len(query.Select) - 1
-	for i, sc := range query.Select {
-		fd.WriteString(sc.FieldStorage)
-		if i == lastColumn {
-			continue
+
+	if writeHeader {
+		for i, sc := range query.Select {
+			fd.WriteString(sc.FieldStorage)
+			if i == lastColumn {
+				continue
+			}
+			fd.WriteString(protocol.CSVDelimiter)
 		}
-		fd.WriteString(protocol.CSVDelimiter)
+		fd.WriteString("\n")
 	}
-	fd.WriteString("\n")
 
 	// And now write the data
 	for i, r := range rows {