Pull request: querylog: more opt

Updates 1273.

Squashed commit of the following:

commit 167c0b5acaab8a2676de2cea556c861dc0efbc72
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Apr 12 18:12:43 2021 +0300

    querylog: imp naming

commit 5010ad113e46335011a721cbcc9fc9b1fc623722
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Apr 12 17:53:41 2021 +0300

    querylog: more opt

HACKING.md

@@ -243,6 +243,33 @@ on GitHub and most other Markdown renderers. -->
 
  *  Use named returns to improve readability of function signatures.
 
+ *  When naming a file which defines an enitity, use singular nouns, unless the
+    entity is some form of a container for other entities:
+
+    ```go
+    // File: client.go
+
+    package foo
+
+    type Client struct {
+            // …
+    }
+    ```
+
+    ```go
+    // File: clients.go
+
+    package foo
+
+    type Clients []*Client
+
+    // …
+
+    type ClientsWithCache struct {
+            // …
+    }
+    ```
+
  ###  <a id="testing" href="#testing">Testing</a>
 
  *  Use `assert.NoError` and `require.NoError` instead of `assert.Nil` and

internal/querylog/decode.go

@@ -575,18 +575,3 @@ func decodeLogEntry(ent *logEntry, str string) {
 		}
 	}
 }
-
-// Get value from "key":"value"
-func readJSONValue(s, name string) string {
-	i := strings.Index(s, "\""+name+"\":\"")
-	if i == -1 {
-		return ""
-	}
-	start := i + 1 + len(name) + 3
-	i = strings.IndexByte(s[start:], '"')
-	if i == -1 {
-		return ""
-	}
-	end := start + i
-	return s[start:end]
-}

internal/querylog/http.go

@@ -126,15 +126,15 @@ func getDoubleQuotesEnclosedValue(s *string) bool {
 	return false
 }
 
-// parseSearchCriteria - parses "searchCriteria" from the specified query parameter
-func (l *queryLog) parseSearchCriteria(q url.Values, name string, ct criteriaType) (bool, searchCriteria, error) {
+// parseSearchCriterion parses a search criterion from the query parameter.
+func (l *queryLog) parseSearchCriterion(q url.Values, name string, ct criterionType) (bool, searchCriterion, error) {
 	val := q.Get(name)
 	if len(val) == 0 {
-		return false, searchCriteria{}, nil
+		return false, searchCriterion{}, nil
 	}
 
-	c := searchCriteria{
-		criteriaType: ct,
+	c := searchCriterion{
+		criterionType: ct,
 		value:         val,
 	}
 	if getDoubleQuotesEnclosedValue(&c.value) {
@@ -175,15 +175,15 @@ func (l *queryLog) parseSearchParams(r *http.Request) (p *searchParams, err erro
 		p.maxFileScanEntries = 0
 	}
 
-	paramNames := map[string]criteriaType{
+	paramNames := map[string]criterionType{
 		"search":          ctDomainOrClient,
 		"response_status": ctFilteringStatus,
 	}
 
 	for k, v := range paramNames {
 		var ok bool
-		var c searchCriteria
-		ok, c, err = l.parseSearchCriteria(q, k, v)
+		var c searchCriterion
+		ok, c, err = l.parseSearchCriterion(q, k, v)
 		if err != nil {
 			return nil, err
 		}

internal/querylog/qlog_test.go

@@ -53,11 +53,11 @@ func TestQueryLog(t *testing.T) {
 
 	testCases := []struct {
 		name string
-		sCr  []searchCriteria
+		sCr  []searchCriterion
 		want []tcAssertion
 	}{{
 		name: "all",
-		sCr:  []searchCriteria{},
+		sCr:  []searchCriterion{},
 		want: []tcAssertion{
 			{num: 0, host: "example.com", answer: net.IPv4(1, 1, 1, 4), client: net.IPv4(2, 2, 2, 4)},
 			{num: 1, host: "test.example.org", answer: net.IPv4(1, 1, 1, 3), client: net.IPv4(2, 2, 2, 3)},
@@ -66,8 +66,8 @@ func TestQueryLog(t *testing.T) {
 		},
 	}, {
 		name: "by_domain_strict",
-		sCr: []searchCriteria{{
-			criteriaType: ctDomainOrClient,
+		sCr: []searchCriterion{{
+			criterionType: ctDomainOrClient,
 			strict:        true,
 			value:         "TEST.example.org",
 		}},
@@ -76,8 +76,8 @@ func TestQueryLog(t *testing.T) {
 		}},
 	}, {
 		name: "by_domain_non-strict",
-		sCr: []searchCriteria{{
-			criteriaType: ctDomainOrClient,
+		sCr: []searchCriterion{{
+			criterionType: ctDomainOrClient,
 			strict:        false,
 			value:         "example.ORG",
 		}},
@@ -88,8 +88,8 @@ func TestQueryLog(t *testing.T) {
 		},
 	}, {
 		name: "by_client_ip_strict",
-		sCr: []searchCriteria{{
-			criteriaType: ctDomainOrClient,
+		sCr: []searchCriterion{{
+			criterionType: ctDomainOrClient,
 			strict:        true,
 			value:         "2.2.2.2",
 		}},
@@ -98,8 +98,8 @@ func TestQueryLog(t *testing.T) {
 		}},
 	}, {
 		name: "by_client_ip_non-strict",
-		sCr: []searchCriteria{{
-			criteriaType: ctDomainOrClient,
+		sCr: []searchCriterion{{
+			criterionType: ctDomainOrClient,
 			strict:        false,
 			value:         "2.2.2",
 		}},

internal/querylog/qlogfile.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"strings"
 	"sync"
 	"time"
 
@@ -321,11 +322,29 @@ func (q *QLogFile) readProbeLine(position int64) (string, int64, int64, error) {
 	return string(buffer[startLine:endLine]), lineIdx, lineEndIdx, nil
 }
 
+// readJSONvalue reads a JSON string in form of '"key":"value"'.  prefix must be
+// of the form '"key":"' to generate less garbage.
+func readJSONValue(s, prefix string) string {
+	i := strings.Index(s, prefix)
+	if i == -1 {
+		return ""
+	}
+
+	start := i + len(prefix)
+	i = strings.IndexByte(s[start:], '"')
+	if i == -1 {
+		return ""
+	}
+
+	end := start + i
+	return s[start:end]
+}
+
 // readQLogTimestamp reads the timestamp field from the query log line
 func readQLogTimestamp(str string) int64 {
-	val := readJSONValue(str, "T")
+	val := readJSONValue(str, `"T":"`)
 	if len(val) == 0 {
-		val = readJSONValue(str, "Time")
+		val = readJSONValue(str, `"Time":"`)
 	}
 
 	if len(val) == 0 {

internal/querylog/querylogfile.go

@@ -118,7 +118,7 @@ func (l *queryLog) readFileFirstTimeValue() int64 {
 	}
 	buf = buf[:r]
 
-	val := readJSONValue(string(buf), "T")
+	val := readJSONValue(string(buf), `"T":"`)
 	t, err := time.Parse(time.RFC3339Nano, val)
 	if err != nil {
 		return -1

internal/querylog/search.go

@@ -171,6 +171,7 @@ func (l *queryLog) searchFiles(
 	for total < params.maxFileScanEntries || params.maxFileScanEntries <= 0 {
 		var e *logEntry
 		var ts int64
+
 		e, ts, err = l.readNextEntry(r, params, cache)
 		if err != nil {
 			if err == io.EOF {
@@ -198,6 +199,29 @@ func (l *queryLog) searchFiles(
 	return entries, oldest, total
 }
 
+// quickMatchClientFinder is a wrapper around the usual client finding function
+// to make it easier to use with quick matches.
+type quickMatchClientFinder struct {
+	client func(clientID, ip string, cache clientCache) (c *Client, err error)
+	cache  clientCache
+}
+
+// findClient is a method that can be used as a quickMatchClientFinder.
+func (f quickMatchClientFinder) findClient(clientID, ip string) (c *Client) {
+	var err error
+	c, err = f.client(clientID, ip, f.cache)
+	if err != nil {
+		log.Error("querylog: enriching file record for quick search:"+
+			" for client %q (client id %q): %s",
+			ip,
+			clientID,
+			err,
+		)
+	}
+
+	return c
+}
+
 // readNextEntry reads the next log entry and checks if it matches the search
 // criteria.  It optionally uses the client cache, if provided.  e is nil if the
 // entry doesn't match the search criteria.  ts is the timestamp of the
@@ -213,6 +237,17 @@ func (l *queryLog) readNextEntry(
 		return nil, 0, err
 	}
 
+	clientFinder := quickMatchClientFinder{
+		client: l.client,
+		cache:  cache,
+	}
+
+	if !params.quickMatch(line, clientFinder.findClient) {
+		ts = readQLogTimestamp(line)
+
+		return nil, ts, nil
+	}
+
 	e = &logEntry{}
 	decodeLogEntry(e, line)
 

internal/querylog/searchcriterion.go

@@ -6,15 +6,15 @@ import (
 	"github.com/AdguardTeam/AdGuardHome/internal/dnsfilter"
 )
 
-type criteriaType int
+type criterionType int
 
 const (
 	// ctDomainOrClient is for searching by the domain name, the client's IP
 	// address, or the clinet's ID.
-	ctDomainOrClient criteriaType = iota
+	ctDomainOrClient criterionType = iota
 	// ctFilteringStatus is for searching by the filtering status.
 	//
-	// See (*searchCriteria).ctFilteringStatusCase for details.
+	// See (*searchCriterion).ctFilteringStatusCase for details.
 	ctFilteringStatus
 )
 
@@ -40,17 +40,83 @@ var filteringStatusValues = []string{
 	filteringStatusProcessed,
 }
 
-// searchCriteria - every search request may contain a list of different search criteria
-// we use each of them to match the query
-type searchCriteria struct {
-	value        string       // search criteria value
-	criteriaType criteriaType // type of the criteria
-	strict       bool         // should we strictly match (equality) or not (indexOf)
+// searchCriterion is a search criterion that is used to match a record.
+type searchCriterion struct {
+	value         string
+	criterionType criterionType
+	// strict, if true, means that the criterion must be applied to the
+	// whole value rather than the part of it.  That is, equality and not
+	// containment.
+	strict bool
 }
 
-// match - checks if the log entry matches this search criteria
-func (c *searchCriteria) match(entry *logEntry) bool {
-	switch c.criteriaType {
+func (c *searchCriterion) ctDomainOrClientCaseStrict(
+	term string,
+	clientID string,
+	name string,
+	host string,
+	ip string,
+) (ok bool) {
+	return strings.EqualFold(host, term) ||
+		strings.EqualFold(clientID, term) ||
+		strings.EqualFold(ip, term) ||
+		strings.EqualFold(name, term)
+}
+
+func (c *searchCriterion) ctDomainOrClientCaseNonStrict(
+	term string,
+	clientID string,
+	name string,
+	host string,
+	ip string,
+) (ok bool) {
+	// TODO(a.garipov): Write a performant, case-insensitive version of
+	// strings.Contains instead of generating garbage.  Or, perhaps in the
+	// future, use a locale-appropriate matcher from golang.org/x/text.
+	clientID = strings.ToLower(clientID)
+	host = strings.ToLower(host)
+	ip = strings.ToLower(ip)
+	name = strings.ToLower(name)
+	term = strings.ToLower(term)
+
+	return strings.Contains(clientID, term) ||
+		strings.Contains(host, term) ||
+		strings.Contains(ip, term) ||
+		strings.Contains(name, term)
+}
+
+// quickMatch quickly checks if the line matches the given search criterion.
+// It returns false if the like doesn't match.  This method is only here for
+// optimisation purposes.
+func (c *searchCriterion) quickMatch(line string, findClient quickMatchClientFunc) (ok bool) {
+	switch c.criterionType {
+	case ctDomainOrClient:
+		host := readJSONValue(line, `"QH":"`)
+		ip := readJSONValue(line, `"IP":"`)
+		clientID := readJSONValue(line, `"CID":"`)
+
+		var name string
+		if cli := findClient(clientID, ip); cli != nil {
+			name = cli.Name
+		}
+
+		if c.strict {
+			return c.ctDomainOrClientCaseStrict(c.value, clientID, name, host, ip)
+		}
+
+		return c.ctDomainOrClientCaseNonStrict(c.value, clientID, name, host, ip)
+	case ctFilteringStatus:
+		// Go on, as we currently don't do quick matches against
+		// filtering statuses.
+		return true
+	default:
+		return true
+	}
+}
+
+// match checks if the log entry matches this search criterion.
+func (c *searchCriterion) match(entry *logEntry) bool {
+	switch c.criterionType {
 	case ctDomainOrClient:
 		return c.ctDomainOrClientCase(entry)
 	case ctFilteringStatus:
@@ -60,14 +126,7 @@ func (c *searchCriteria) match(entry *logEntry) bool {
 	return false
 }
 
-func (c *searchCriteria) ctDomainOrClientCaseStrict(term, clientID, name, host, ip string) bool {
-	return strings.EqualFold(host, term) ||
-		strings.EqualFold(clientID, term) ||
-		strings.EqualFold(ip, term) ||
-		strings.EqualFold(name, term)
-}
-
-func (c *searchCriteria) ctDomainOrClientCase(e *logEntry) bool {
+func (c *searchCriterion) ctDomainOrClientCase(e *logEntry) bool {
 	clientID := e.ClientID
 	host := e.QHost
 
@@ -82,22 +141,10 @@ func (c *searchCriteria) ctDomainOrClientCase(e *logEntry) bool {
 		return c.ctDomainOrClientCaseStrict(term, clientID, name, host, ip)
 	}
 
-	// TODO(a.garipov): Write a case-insensitive version of strings.Contains
-	// instead of generating garbage.  Or, perhaps in the future, use
-	// a locale-appropriate matcher from golang.org/x/text.
-	clientID = strings.ToLower(clientID)
-	host = strings.ToLower(host)
-	ip = strings.ToLower(ip)
-	name = strings.ToLower(name)
-	term = strings.ToLower(term)
-
-	return strings.Contains(clientID, term) ||
-		strings.Contains(host, term) ||
-		strings.Contains(ip, term) ||
-		strings.Contains(name, term)
+	return c.ctDomainOrClientCaseNonStrict(term, clientID, name, host, ip)
 }
 
-func (c *searchCriteria) ctFilteringStatusCase(res dnsfilter.Result) bool {
+func (c *searchCriterion) ctFilteringStatusCase(res dnsfilter.Result) bool {
 	switch c.value {
 	case filteringStatusAll:
 		return true

internal/querylog/searchparams.go

@@ -5,7 +5,7 @@ import "time"
 // searchParams represent the search query sent by the client
 type searchParams struct {
 	// searchCriteria - list of search criteria that we use to get filter results
-	searchCriteria []searchCriteria
+	searchCriteria []searchCriterion
 
 	// olderThen - return entries that are older than this value
 	// if not set - disregard it and return any value
@@ -27,6 +27,22 @@ func newSearchParams() *searchParams {
 	}
 }
 
+// quickMatchClientFunc is a simplified client finder for quick matches.
+type quickMatchClientFunc = func(clientID, ip string) (c *Client)
+
+// quickMatch quickly checks if the line matches the given search parameters.
+// It returns false if the line doesn't match.  This method is only here for
+// optimisation purposes.
+func (s *searchParams) quickMatch(line string, findClient quickMatchClientFunc) (ok bool) {
+	for _, c := range s.searchCriteria {
+		if !c.quickMatch(line, findClient) {
+			return false
+		}
+	}
+
+	return true
+}
+
 // match - checks if the logEntry matches the searchParams
 func (s *searchParams) match(entry *logEntry) bool {
 	if !s.olderThan.IsZero() && entry.Time.UnixNano() >= s.olderThan.UnixNano() {