MM-22785 audit server CLI (#14144)

Add auditing to server CLI.

Also:
- simplify auditing in API layer
- reduce number of AddMeta calls
- have models serialize themselves
- more consistent field naming

audit/record.go

@@ -6,6 +6,10 @@ package audit
 // Meta represents metadata that can be added to a audit record as name/value pairs.
 type Meta map[string]interface{}
 
+// FuncMetaTypeConv defines a function that can convert meta data types into something
+// that serializes well for audit records.
+type FuncMetaTypeConv func(val interface{}) (newVal interface{}, converted bool)
+
 // Record provides a consistent set of fields used for all audit logging.
 type Record struct {
 	APIPath   string
@@ -16,6 +20,7 @@ type Record struct {
 	Client    string
 	IPAddress string
 	Meta      Meta
+	metaConv  []FuncMetaTypeConv
 }
 
 // Success marks the audit record status as successful.
@@ -33,5 +38,22 @@ func (rec *Record) AddMeta(name string, val interface{}) {
 	if rec.Meta == nil {
 		rec.Meta = Meta{}
 	}
+
+	// possibly convert val to something better suited for serializing
+	// via zero or more conversion functions.
+	var converted bool
+	for _, conv := range rec.metaConv {
+		val, converted = conv(val)
+		if converted {
+			break
+		}
+	}
+
 	rec.Meta[name] = val
 }
+
+// AddMetaTypeConverter adds a function capable of converting meta field types
+// into something more suitable for serialization.
+func (rec *Record) AddMetaTypeConverter(f FuncMetaTypeConv) {
+	rec.metaConv = append(rec.metaConv, f)
+}

audit/record_test.go

@@ -0,0 +1,76 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package audit
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+type bloated struct {
+	fld1 string
+	fld2 string
+	fld3 string
+	fld4 string
+}
+
+type wilted struct {
+	wilt1 string
+}
+
+func conv(val interface{}) (interface{}, bool) {
+	switch v := val.(type) {
+	case *bloated:
+		return &wilted{wilt1: v.fld1}, true
+	}
+	return val, false
+}
+
+func TestRecord_AddMeta(t *testing.T) {
+	type fields struct {
+		metaConv []FuncMetaTypeConv
+	}
+	type args struct {
+		name string
+		val  interface{}
+	}
+	tests := []struct {
+		name     string
+		fields   fields
+		args     args
+		wantWilt bool
+		wantVal  string
+	}{
+		{name: "no converter", wantWilt: false, wantVal: "ok", fields: fields{}, args: args{name: "prop", val: "ok"}},
+		{name: "don't convert", wantWilt: false, wantVal: "ok", fields: fields{metaConv: []FuncMetaTypeConv{conv}}, args: args{name: "prop", val: "ok"}},
+		{name: "convert", wantWilt: true, wantVal: "1", fields: fields{metaConv: []FuncMetaTypeConv{conv}}, args: args{name: "prop", val: &bloated{
+			fld1: "1", fld2: "2", fld3: "3", fld4: "4"}},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			rec := &Record{
+				metaConv: tt.fields.metaConv,
+			}
+			rec.AddMeta(tt.args.name, tt.args.val)
+
+			// fetch the prop store in auditRecord meta data
+			got, ok := rec.Meta["prop"]
+			require.True(t, ok)
+
+			// check if conversion was expected
+			val, ok := got.(*wilted)
+			require.Equal(t, tt.wantWilt, ok)
+
+			if ok {
+				// if converted to wilt then make sure field was copied
+				require.Equal(t, tt.wantVal, val.wilt1)
+			} else {
+				// if not converted, make sure val is unchanged
+				require.Equal(t, tt.wantVal, got)
+			}
+		})
+	}
+}

audit/syslogtls.go

@@ -54,8 +54,7 @@ func NewSyslogTLSTarget(filter logr.Filter, formatter logr.Formatter, params *Sy
 	return s, nil
 }
 
-// Shutdown stops processing log records after making best
-// effort to flush queue.
+// Shutdown stops processing log records after making best effort to flush queue.
 func (s *SyslogTLS) Shutdown(ctx context.Context) error {
 	errs := merror.New()