Add a parser for VSL query strings.

pkg/log/query_parser_test.go

+/*-
+ * Copyright (c) 2018 UPLEX Nils Goroll Systemoptimierung
+ * All rights reserved
+ *
+ * Author: Geoffrey Simmons <geoffrey.simmons@uplex.de>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+package log
+
+import (
+	"bytes"
+	"testing"
+)
+
+type expLHS struct {
+	tags   []string
+	prefix string
+	field  int
+	level  int
+	lvlCmp int
+	vxid   bool
+}
+
+type expRHS struct {
+	str      string
+	intVal   int
+	floatVal float64
+	rhsType  rhsType
+}
+
+type expExpr struct {
+	pass bool
+	aNil bool
+	bNil bool
+	lhs  expLHS
+	rhs  expRHS
+	tok  qTokenType
+}
+
+type expParse struct {
+	query string
+	expr  expExpr
+}
+
+func bitmap2Tags(bits [32]byte) []string {
+	var strs []string
+	for i, b := range bits {
+		if b == 0 {
+			continue
+		}
+		for j := 0; j < 8; j++ {
+			if (1<<uint(j))&b != 0 {
+				tagnum := i*8 + j
+				strs = append(strs, Tags[tagnum].String)
+			}
+		}
+	}
+	return strs
+}
+
+func checkLHS(t *testing.T, exp expLHS, got qLHS) {
+	strs := bitmap2Tags(got.tags)
+	for i, s := range exp.tags {
+		if s != strs[i] {
+			t.Errorf("lhs tag want=%v got=%v", s, strs[i])
+		}
+	}
+	if bytes.Compare(got.prefix, []byte(exp.prefix)) != 0 {
+		t.Errorf("lhs prefix want=%v got=%v", exp.prefix,
+			string(got.prefix))
+	}
+	if got.field != exp.field {
+		t.Errorf("lhs field want=%v got=%v", exp.field, got.field)
+	}
+	if got.level != exp.level {
+		t.Errorf("lhs level want=%v got=%v", exp.level, got.level)
+	}
+	if got.lvlCmp != exp.lvlCmp {
+		t.Errorf("lhs level plus/minus want=%v got=%v", exp.lvlCmp,
+			got.lvlCmp)
+	}
+}
+
+func checkRHS(t *testing.T, exp expRHS, got qRHS) {
+	if exp.rhsType != got.rhsType {
+		t.Errorf("rhs type want=%v got=%v", exp.rhsType, got.rhsType)
+		return
+	}
+	switch got.rhsType {
+	case integer:
+		if exp.intVal != got.intVal {
+			t.Errorf("rhs intVal want=%v got=%v", exp.intVal,
+				got.intVal)
+		}
+	case float:
+		if exp.floatVal != got.floatVal {
+			t.Errorf("rhs floatVal want=%v got=%v", exp.floatVal,
+				got.floatVal)
+		}
+	case strType:
+		if exp.str != string(got.strVal) {
+			t.Errorf("rhs strVal want=%v got=%v", exp.str,
+				string(got.strVal))
+		}
+	case regex:
+		if got.regex == nil {
+			t.Error("rhs regex want=true got=false")
+		}
+	}
+}
+
+// Examples from vsl-query(7), b00050.vtc, l00000.vtc, l00001.vtc
+var expParses = []expParse{
+	{query: `ReqURL eq "/foo"`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"ReqURL"},
+				level: -1,
+			},
+			rhs: expRHS{
+				str:     "/foo",
+				rhsType: strType,
+			},
+			tok: seq,
+		},
+	},
+	{query: `ReqHeader:cookie`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:   []string{"ReqHeader"},
+				prefix: "cookie",
+				level:  -1,
+			},
+			rhs: expRHS{rhsType: empty},
+		},
+	},
+	{query: `not ReqHeader:cookie`,
+		expr: expExpr{
+			pass: true,
+			aNil: false,
+			bNil: true,
+			tok:  not,
+		},
+	},
+	{query: `Timestamp:Process[2] > 0.8`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:   []string{"Timestamp"},
+				level:  -1,
+				prefix: "Process",
+				field:  2,
+			},
+			rhs: expRHS{
+				floatVal: 0.8,
+				rhsType:  float,
+			},
+			tok: gt,
+		},
+	},
+	{query: `ReqHeader:user-agent ~ "iPod" and Timestamp:Resp[2] > 1.`,
+		expr: expExpr{
+			pass: true,
+			aNil: false,
+			bNil: false,
+			tok:  and,
+		},
+	},
+	{query: "BerespStatus >= 500",
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"BerespStatus"},
+				level: -1,
+			},
+			rhs: expRHS{
+				intVal:  500,
+				rhsType: integer,
+			},
+			tok: geq,
+		},
+	},
+	{query: "ReqStatus == 304 and not ReqHeader:if-modified-since",
+		expr: expExpr{
+			pass: true,
+			aNil: false,
+			bNil: false,
+			tok:  and,
+		},
+	},
+	{query: "BerespStatus >= 500 or {2+}Timestamp:Process[2] > 1.",
+		expr: expExpr{
+			pass: true,
+			aNil: false,
+			bNil: false,
+			tok:  or,
+		},
+	},
+	{query: "vxid == 0 and Error",
+		expr: expExpr{
+			pass: true,
+			aNil: false,
+			bNil: false,
+			tok:  and,
+		},
+	},
+	{query: "vxid == 1001",
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs:  expLHS{vxid: true},
+			rhs: expRHS{
+				intVal:  1001,
+				rhsType: integer,
+			},
+			tok: eq,
+		},
+	},
+	{query: "vxid ~ 1001"},
+	{query: "vxid !~ 1001"},
+	{query: "vxid eq 1001"},
+	{query: "vxid ne 1001"},
+	{query: "vxid != 1001.5"},
+	{query: "vxid[1] >= 1001"},
+	{query: "{1}vxid <= 1001"},
+	{query: "vxid,Link > 1001"},
+	{query: "vxid,vxid < 1001"},
+	// XXX currently don't support single-quoted strings, text/scanner
+	// does not interpret them as strings.
+	// {query: "Begin ~ 'bereq 1001'",
+	{query: `Begin ~ "bereq 1001"`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"Begin"},
+				level: -1,
+			},
+			rhs: expRHS{
+				str:     "bereq 1001",
+				rhsType: regex,
+			},
+			tok: match,
+		},
+	},
+	{query: `ReqProtocol ne "HTTP/1.0"`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"ReqProtocol"},
+				level: -1,
+			},
+			rhs: expRHS{
+				str:     "HTTP/1.0",
+				rhsType: strType,
+			},
+			tok: sneq,
+		},
+	},
+	{query: `RespStatus == 200`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"RespStatus"},
+				level: -1,
+			},
+			rhs: expRHS{
+				intVal:  200,
+				rhsType: integer,
+			},
+			tok: eq,
+		},
+	},
+	{query: `RespStatus == 200.`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"RespStatus"},
+				level: -1,
+			},
+			rhs: expRHS{
+				floatVal: 200.,
+				rhsType:  float,
+			},
+			tok: eq,
+		},
+	},
+	{query: `RespStatus != 503`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"RespStatus"},
+				level: -1,
+			},
+			rhs: expRHS{
+				intVal:  503,
+				rhsType: integer,
+			},
+			tok: neq,
+		},
+	},
+	{query: `RespStatus != 503.`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags:  []string{"RespStatus"},
+				level: -1,
+			},
+			rhs: expRHS{
+				floatVal: 503.,
+				rhsType:  float,
+			},
+			tok: neq,
+		},
+	},
+	{query: `Debug,Resp* == 200`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags: []string{"Debug", "RespMethod",
+					"RespURL", "RespProtocol", "RespStatus",
+					"RespReason", "RespHeader", "RespUnset",
+					"RespLost"},
+				level: -1,
+			},
+			rhs: expRHS{
+				intVal:  200,
+				rhsType: integer,
+			},
+			tok: eq,
+		},
+	},
+	{query: `Resp*:x-test eq "123 321"`,
+		expr: expExpr{
+			pass: true,
+			aNil: true,
+			bNil: true,
+			lhs: expLHS{
+				tags: []string{"RespMethod", "RespURL",
+					"RespProtocol", "RespStatus",
+					"RespReason", "RespHeader", "RespUnset",
+					"RespLost"},
+				level:  -1,
+				prefix: "x-test",
+			},
+			rhs: expRHS{
+				str:     "123 321",
+				rhsType: strType,
+			},
+			tok: seq,
+		},
+	},
+}
+
+func TestParser(t *testing.T) {
+	for _, exp := range expParses {
+		expr, err := parseQuery(exp.query)
+		if exp.expr.pass && err != nil {
+			t.Errorf("Could not parse '%s' as expected: %v",
+				exp.query, err)
+		}
+		if !exp.expr.pass && err == nil {
+			t.Errorf("Did not fail to parse '%s' as expected",
+				exp.query)
+		}
+		if err != nil {
+			continue
+		}
+		if exp.expr.aNil != (expr.a == nil) {
+			t.Errorf("expr.a==nil want=%v got=%v", exp.expr.aNil,
+				expr.a == nil)
+		}
+		if exp.expr.bNil != (expr.b == nil) {
+			t.Errorf("expr.b==nil want=%v got=%v", exp.expr.bNil,
+				expr.b == nil)
+		}
+		if exp.expr.tok != expr.tok {
+			t.Errorf("expr.tok want=%v got=%v", exp.expr.tok,
+				expr.tok)
+		}
+		if expr.a != nil {
+			continue
+		}
+		if exp.expr.lhs.vxid != expr.lhs.vxid {
+			t.Errorf("lhs vxid want=%v got=%v", exp.expr.lhs.vxid,
+				expr.lhs.vxid)
+		}
+		if !expr.lhs.vxid {
+			checkLHS(t, exp.expr.lhs, expr.lhs)
+		}
+		checkRHS(t, exp.expr.rhs, expr.rhs)
+	}
+}