Merge branch 'append-query-results-to-outfile-when-in-streaming-mode' into 'master'

Add "append" modifier to "outfile" keyword in mapreduce query.

See merge request Storage/dtail!6

8 files changed, 574 insertions, 28 deletions

diff --git a/doc/querylanguage.md b/doc/querylanguage.md
index 41e95de..c3e567e 100644
--- a/doc/querylanguage.md
+++ b/doc/querylanguage.md
@@ -35,7 +35,7 @@ QUERY := select SELECT1[,SELECT2...]
          [set SET1,[,SET2...]]
          [interval NUMBER]
          [limit NUMBER]
-         [outfile STRING]
+         [outfile [append] STRING]
          [logformat LOGFORMAT]
 ```
 
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 @@
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+2,1002-071558,11.000000,11.000000,11.000000
+2,1002-071656,11.000000,11.000000,11.000000
+2,1002-071417,11.000000,11.000000,11.000000
+2,1002-071918,11.000000,11.000000,11.000000
+2,1002-071836,11.000000,11.000000,11.000000
+2,1002-071658,11.000000,11.000000,11.000000
+2,1002-071848,11.000000,11.000000,11.000000
+2,1002-071916,11.000000,11.000000,11.000000
+2,1002-071538,11.000000,11.000000,11.000000
+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 d466d9f..a378fb5 100644
--- a/integrationtests/dmap_test.go
+++ b/integrationtests/dmap_test.go
@@ -65,7 +65,7 @@ func testDmap1(t *testing.T, query, subtestName string, usePipe bool) error {
 			"--cfg", "none",
 			"--query", query,
 			"--logger", "stdout",
-			"--logLevel", "error",
+			"--logLevel", "info",
 			"--noColor")
 	} else {
 		stdoutCh, stderrCh, cmdErrCh, err = startCommand(ctx, t,
@@ -73,7 +73,7 @@ func testDmap1(t *testing.T, query, subtestName string, usePipe bool) error {
 			"--cfg", "none",
 			"--query", query,
 			"--logger", "stdout",
-			"--logLevel", "error",
+			"--logLevel", "info",
 			"--noColor",
 			inFile)
 	}
@@ -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
+	// file 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/io/dlog/loggers/file.go b/internal/io/dlog/loggers/file.go
index 9dce251..6a09353 100644
--- a/internal/io/dlog/loggers/file.go
+++ b/internal/io/dlog/loggers/file.go
@@ -141,7 +141,7 @@ func (f *file) getWriter(name string) *bufio.Writer {
 	}
 
 	logFile := fmt.Sprintf("%s/%s.log", config.Common.LogDir, name)
-	newFd, err := os.OpenFile(logFile, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0644)
+	newFd, err := os.OpenFile(logFile, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0666)
 	if err != nil {
 		panic(err)
 	}
diff --git a/internal/mapr/groupsetresult.go b/internal/mapr/groupsetresult.go
index 6d0ac1f..9c3c134 100644
--- a/internal/mapr/groupsetresult.go
+++ b/internal/mapr/groupsetresult.go
@@ -159,11 +159,11 @@ func (g *GroupSet) resultWriteFormattedDataEntry(query *Query, sb *strings.Build
 }
 
 func (*GroupSet) writeQueryFile(query *Query) error {
-	queryFile := fmt.Sprintf("%s.query", query.Outfile)
+	queryFile := fmt.Sprintf("%s.query", query.Outfile.FilePath)
 	tmpQueryFile := fmt.Sprintf("%s.tmp", queryFile)
 	dlog.Common.Debug("Writing query file", queryFile)
 
-	fd, err := os.Create(tmpQueryFile)
+	fd, err := os.OpenFile(tmpQueryFile, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0666)
 	if err != nil {
 		return err
 	}
@@ -187,31 +187,49 @@ func (g *GroupSet) WriteResult(query *Query) error {
 		return err
 	}
 
-	dlog.Common.Info("Writing outfile", query.Outfile)
-	tmpOutfile := fmt.Sprintf("%s.tmp", query.Outfile)
+	// By default, also write the CSV header.
+	writeHeader := true
 
-	fd, err := os.Create(tmpOutfile)
+	// 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, tmpOutfile, fd)
+	return g.resultWriteUnformatted(query, rows, fd, writeHeader)
 }
 
-func (g *GroupSet) resultWriteUnformatted(query *Query, rows []result, tmpOutfile string,
-	fd *os.File) error {
+func (g *GroupSet) getOutfileFD(query *Query) (*os.File, error) {
+	if !query.Outfile.AppendMode {
+		dlog.Common.Info("Writing to outfile", query.Outfile.FilePath)
+		tmpOutfile := fmt.Sprintf("%s.tmp", query.Outfile.FilePath)
+		return os.OpenFile(tmpOutfile, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0666)
+	}
+
+	dlog.Common.Info("Appending to outfile", query.Outfile.FilePath)
+	return os.OpenFile(query.Outfile.FilePath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
+}
 
-	// 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 {
@@ -228,9 +246,12 @@ func (g *GroupSet) resultWriteUnformatted(query *Query, rows []result, tmpOutfil
 		fd.WriteString("\n")
 	}
 
-	if err := os.Rename(tmpOutfile, query.Outfile); err != nil {
-		os.Remove(tmpOutfile)
-		return err
+	if !query.Outfile.AppendMode {
+		tmpOutfile := fmt.Sprintf("%s.tmp", query.Outfile.FilePath)
+		if err := os.Rename(tmpOutfile, query.Outfile.FilePath); err != nil {
+			os.Remove(tmpOutfile)
+			return err
+		}
 	}
 
 	return nil
diff --git a/internal/mapr/query.go b/internal/mapr/query.go
index d70675f..4eeb7b6 100644
--- a/internal/mapr/query.go
+++ b/internal/mapr/query.go
@@ -13,6 +13,15 @@ const (
 	unexpectedEnd string = "Unexpected end of query"
 )
 
+type Outfile struct {
+	FilePath   string
+	AppendMode bool
+}
+
+func (o Outfile) String() string {
+	return fmt.Sprintf("Outfile(FilePath:%v,AppendMode:%v)", o.FilePath, o.AppendMode)
+}
+
 // Query represents a parsed mapr query.
 type Query struct {
 	Select       []selectCondition
@@ -25,7 +34,7 @@ type Query struct {
 	GroupKey     string
 	Interval     time.Duration
 	Limit        int
-	Outfile      string
+	Outfile      *Outfile
 	RawQuery     string
 	tokens       []token
 	LogFormat    string
@@ -68,7 +77,7 @@ func NewQuery(queryStr string) (*Query, error) {
 
 // HasOutfile returns true if query result will be written to a CVS output file.
 func (q *Query) HasOutfile() bool {
-	return q.Outfile != ""
+	return q.Outfile != nil
 }
 
 // Has is a helper to determine whether a query contains a substring
@@ -193,10 +202,18 @@ func (q *Query) parseTokens(tokens []token) ([]token, error) {
 			q.Limit = i
 		case "outfile":
 			tokens, found = tokensConsume(tokens[1:])
-			if len(found) == 0 {
-				return tokens, errors.New(invalidQuery + unexpectedEnd)
+			switch len(found) {
+			case 1:
+				q.Outfile = &Outfile{FilePath: found[0].str, AppendMode: false}
+			case 2:
+				if found[0].str == "append" {
+					q.Outfile = &Outfile{FilePath: found[1].str, AppendMode: true}
+				} else {
+					return tokens, errors.New(invalidQuery + invalidQuery)
+				}
+			default:
+				return tokens, errors.New(invalidQuery + invalidQuery)
 			}
-			q.Outfile = found[0].str
 		case "logformat":
 			tokens, found = tokensConsume(tokens[1:])
 			if len(found) == 0 {
diff --git a/internal/mapr/query_test.go b/internal/mapr/query_test.go
index a0913fd..f03ccba 100644
--- a/internal/mapr/query_test.go
+++ b/internal/mapr/query_test.go
@@ -5,6 +5,48 @@ import (
 	"time"
 )
 
+func TestParseQueryOutfile(t *testing.T) {
+	queryStr := "select foo from bar outfile \"baz.csv\""
+
+	q, err := NewQuery(queryStr)
+	if err != nil {
+		t.Errorf("Query parse error: %s\n%v: %v", queryStr, q, err)
+	}
+
+	if q.Outfile == nil {
+		t.Errorf("Expected non-nil outfile: %s\n%v", queryStr, q)
+	}
+
+	if q.Outfile.FilePath != "baz.csv" {
+		t.Errorf("Expected \"baz.csv\" as outfile file path: %s\n%v", queryStr, q)
+	}
+
+	if q.Outfile.AppendMode {
+		t.Errorf("Expected append mode of outfile to be false: %s\n%v", queryStr, q)
+	}
+}
+
+func TestParseQueryOutfileAppend(t *testing.T) {
+	queryStr := "select foo from bar outfile append \"baz.csv\""
+
+	q, err := NewQuery(queryStr)
+	if err != nil {
+		t.Errorf("Query parse error: %s\n%v: %v", queryStr, q, err)
+	}
+
+	if q.Outfile == nil {
+		t.Errorf("Expected non-nil outfile: %s\n%v", queryStr, q)
+	}
+
+	if q.Outfile.FilePath != "baz.csv" {
+		t.Errorf("Expected \"baz.csv\" as outfile file path: %s\n%v", queryStr, q)
+	}
+
+	if !q.Outfile.AppendMode {
+		t.Errorf("Expected append mode of outfile to be true: %s\n%v", queryStr, q)
+	}
+}
+
 func TestParseQuerySimple(t *testing.T) {
 	errorQueries := []string{
 		"select",
@@ -30,7 +72,9 @@ func TestParseQuerySimple(t *testing.T) {
 		"select foo from bar where baz < 100 bay eq 12 group by foo, bar, baz " +
 			"order by foo limit 23 outfile \"result.csv\"",
 		"select foo from bar where baz < 100 bay eq 12 group by foo, bar, baz " +
-			"order by foo limit 23 outfile \"result.csv\" " +
+			"order by foo limit 23 outfile append \"result.csv\"",
+		"select foo from bar where baz < 100 bay eq 12 group by foo, bar, baz " +
+			"order by foo limit 23 outfile append \"result.csv\" " +
 			"set $foo = maskdigits(bar), $baz = 12, $bay = $foo;",
 	}