add logfmt code

* our own "tail -f" implementation in tail.go
* filtering and formatting on per-line basis in handleline.go
* recognition of vespa-internal components in internal.go
* cobra-compatible flags for "level" in levelflags.go
* cobra-compatible flags for "show" in showflags.go
* cobra-compatible flag for regex handling in regexflag.go
* options designed for compatibility with perl version in options.go
* entrypoint in runlogfmt.go

1 files changed, 38 insertions, 0 deletions

diff --git a/client/go/cmd/logfmt/regexflag.go b/client/go/cmd/logfmt/regexflag.go
new file mode 100644
index 00000000000..8f7d2a91373
--- /dev/null
+++ b/client/go/cmd/logfmt/regexflag.go
@@ -0,0 +1,38 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+// vespa logfmt command
+// Author: arnej
+
+package logfmt
+
+import (
+	"regexp"
+)
+
+// optional regular expression filter, as a CLI flag
+
+type regexFlag struct {
+	regex *regexp.Regexp
+}
+
+func (re regexFlag) unmatched(s string) bool {
+	if re.regex == nil {
+		return false
+	}
+	return re.regex.FindStringIndex(s) == nil
+}
+
+func (v *regexFlag) Type() string {
+	return "regular expression"
+}
+
+func (v *regexFlag) String() string {
+	if v.regex == nil {
+		return "<none>"
+	}
+	return v.regex.String()
+}
+
+func (v *regexFlag) Set(val string) (r error) {
+	v.regex, r = regexp.Compile(val)
+	return
+}