Robots.txt support implemented

README.md

@@ -9,12 +9,11 @@ Geziyor is a blazing fast web crawling and web scraping framework. It can be use
 - 5.000+ Requests/Sec
 - JS Rendering
 - Caching (Memory/Disk)
-- Automatic Data Extracting (CSS Selectors)
 - Automatic Data Exporting (JSON, CSV, or custom)
 - Metrics (Prometheus, Expvar, or custom)
 - Limit Concurrency (Global/Per Domain)
 - Request Delays (Constant/Randomized)
-- Cookies and Middlewares
+- Cookies, Middlewares, robots.txt
 - Automatic response decoding to UTF-8
 
 See scraper [Options](https://godoc.org/github.com/geziyor/geziyor#Options) for all custom settings. 
@@ -64,6 +63,8 @@ See [tests](https://github.com/geziyor/geziyor/blob/master/geziyor_test.go) for
 
 ### Installation
 
+Go 1.12 required
+
     go get github.com/geziyor/geziyor
 
 **NOTE**: macOS limits the maximum number of open file descriptors.
@@ -161,7 +162,6 @@ ok  	github.com/geziyor/geziyor	22.861s
 If you're interested in helping this project, please consider these features:
 
 - Command line tool for: pausing and resuming scraper etc. (like [this](https://docs.scrapy.org/en/latest/topics/commands.html))
-- Deploying Scrapers to Cloud
 - ~~Automatically exporting extracted data to multiple places (AWS, FTP, DB, JSON, CSV etc)~~ 
 - Downloading media (Images, Videos etc) (like [this](https://docs.scrapy.org/en/latest/topics/media-pipeline.html))
 - ~~Realtime metrics (Prometheus etc.)~~

client/client.go

@@ -74,11 +74,10 @@ func NewClient(maxBodySize int64, charsetDetectDisabled bool, retryTimes int, re
 
 // DoRequest selects appropriate request handler, client or Chrome
 func (c *Client) DoRequest(req *Request) (*Response, error) {
-	if !req.Rendered {
-		return c.DoRequestClient(req)
-	} else {
+	if req.Rendered {
 		return c.DoRequestChrome(req)
 	}
+	return c.DoRequestClient(req)
 }
 
 // DoRequestClient is a simple wrapper to read response according to options.

geziyor.go

@@ -20,8 +20,8 @@ type Geziyor struct {
 	Exports chan interface{}
 
 	metrics        *metrics.Metrics
-	requestMiddlewares  []middleware.RequestProcessor
-	responseMiddlewares []middleware.ResponseProcessor
+	reqMiddlewares []middleware.RequestProcessor
+	resMiddlewares []middleware.ResponseProcessor
 	wgRequests     sync.WaitGroup
 	wgExporters    sync.WaitGroup
 	semGlobal      chan struct{}
@@ -37,23 +37,19 @@ func NewGeziyor(opt *Options) *Geziyor {
 	geziyor := &Geziyor{
 		Opt:     opt,
 		Exports: make(chan interface{}, 1),
-		requestMiddlewares: []middleware.RequestProcessor{
+		reqMiddlewares: []middleware.RequestProcessor{
 			&middleware.AllowedDomains{AllowedDomains: opt.AllowedDomains},
 			&middleware.DuplicateRequests{RevisitEnabled: opt.URLRevisitEnabled},
 			&middleware.Headers{UserAgent: opt.UserAgent},
 			middleware.NewDelay(opt.RequestDelayRandomize, opt.RequestDelay),
 		},
-		responseMiddlewares: []middleware.ResponseProcessor{
+		resMiddlewares: []middleware.ResponseProcessor{
 			&middleware.ParseHTML{ParseHTMLDisabled: opt.ParseHTMLDisabled},
 			&middleware.LogStats{LogDisabled: opt.LogDisabled},
 		},
 		metrics: metrics.NewMetrics(opt.MetricsType),
 	}
 
-	metricsMiddleware := &middleware.Metrics{Metrics: geziyor.metrics}
-	geziyor.requestMiddlewares = append(geziyor.requestMiddlewares, metricsMiddleware)
-	geziyor.responseMiddlewares = append(geziyor.responseMiddlewares, metricsMiddleware)
-
 	// Default
 	if opt.UserAgent == "" {
 		opt.UserAgent = client.DefaultUserAgent
@@ -67,6 +63,7 @@ func NewGeziyor(opt *Options) *Geziyor {
 	if len(opt.RetryHTTPCodes) == 0 {
 		opt.RetryHTTPCodes = client.DefaultRetryHTTPCodes
 	}
+
 	// Client
 	geziyor.Client = client.NewClient(opt.MaxBodySize, opt.CharsetDetectDisabled, opt.RetryTimes, opt.RetryHTTPCodes)
 	if opt.Cache != nil {
@@ -82,6 +79,7 @@ func NewGeziyor(opt *Options) *Geziyor {
 	if opt.MaxRedirect != 0 {
 		geziyor.Client.CheckRedirect = client.NewRedirectionHandler(opt.MaxRedirect)
 	}
+
 	// Concurrency
 	if opt.ConcurrentRequests != 0 {
 		geziyor.semGlobal = make(chan struct{}, opt.ConcurrentRequests)
@@ -92,9 +90,19 @@ func NewGeziyor(opt *Options) *Geziyor {
 			hostSems map[string]chan struct{}
 		}{hostSems: make(map[string]chan struct{})}
 	}
-	// Middlewares
-	geziyor.requestMiddlewares = append(geziyor.requestMiddlewares, opt.RequestMiddlewares...)
-	geziyor.responseMiddlewares = append(geziyor.responseMiddlewares, opt.ResponseMiddlewares...)
+
+	// Base Middlewares
+	metricsMiddleware := &middleware.Metrics{Metrics: geziyor.metrics}
+	geziyor.reqMiddlewares = append(geziyor.reqMiddlewares, metricsMiddleware)
+	geziyor.resMiddlewares = append(geziyor.resMiddlewares, metricsMiddleware)
+
+	robotsMiddleware := middleware.NewRobotsTxt(geziyor.Client, opt.RobotsTxtDisabled)
+	geziyor.reqMiddlewares = append(geziyor.reqMiddlewares, robotsMiddleware)
+
+	// Custom Middlewares
+	geziyor.reqMiddlewares = append(geziyor.reqMiddlewares, opt.RequestMiddlewares...)
+	geziyor.resMiddlewares = append(geziyor.resMiddlewares, opt.ResponseMiddlewares...)
+
 	// Logging
 	if opt.LogDisabled {
 		log.SetOutput(ioutil.Discard)
@@ -200,7 +208,7 @@ func (g *Geziyor) do(req *client.Request, callback func(g *Geziyor, r *client.Re
 	}
 	defer g.recoverMe()
 
-	for _, middlewareFunc := range g.requestMiddlewares {
+	for _, middlewareFunc := range g.reqMiddlewares {
 		middlewareFunc.ProcessRequest(req)
 		if req.Cancelled {
 			return
@@ -213,7 +221,7 @@ func (g *Geziyor) do(req *client.Request, callback func(g *Geziyor, r *client.Re
 		return
 	}
 
-	for _, middlewareFunc := range g.responseMiddlewares {
+	for _, middlewareFunc := range g.resMiddlewares {
 		middlewareFunc.ProcessResponse(res)
 	}
 

geziyor_test.go

@@ -187,6 +187,16 @@ func TestConcurrentRequests(t *testing.T) {
 	}).Start()
 }
 
+func TestRobots(t *testing.T) {
+	defer leaktest.Check(t)()
+	geziyor.NewGeziyor(&geziyor.Options{
+		StartURLs: []string{"https://httpbin.org/deny"},
+		ParseFunc: func(g *geziyor.Geziyor, r *client.Response) {
+			t.Error("/deny should be blocked by robots.txt middleware")
+		},
+	}).Start()
+}
+
 // Make sure to increase open file descriptor limits before running
 func BenchmarkRequests(b *testing.B) {
 

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/pkg/errors v0.8.1
 	github.com/prometheus/client_golang v1.0.0
 	github.com/stretchr/testify v1.3.0
+	github.com/temoto/robotstxt v1.1.1
 	golang.org/x/net v0.0.0-20190522155817-f3200d17e092
 	golang.org/x/text v0.3.2
 )

go.sum

@@ -69,6 +69,8 @@ github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/temoto/robotstxt v1.1.1 h1:Gh8RCs8ouX3hRSxxK7B1mO5RFByQ4CmJZDwgom++JaA=
+github.com/temoto/robotstxt v1.1.1/go.mod h1:+1AmkuG3IYkh1kv0d2qEB9Le88ehNO0zwOr3ujewlOo=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/net v0.0.0-20180218175443-cbe0f9307d01/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=

middleware/middleware.go

@@ -4,6 +4,7 @@ import (
 	"github.com/geziyor/geziyor/client"
 )
 
+// RequestResponseProcessor interface is for middlewares that needs to process both requests and responses
 type RequestResponseProcessor interface {
 	RequestProcessor
 	ResponseProcessor

middleware/robotstxt.go

@@ -0,0 +1,63 @@
+package middleware
+
+import (
+	"github.com/geziyor/geziyor/client"
+	"github.com/temoto/robotstxt"
+	"log"
+	"sync"
+)
+
+// RobotsTxt middleware filters out requests forbidden by the robots.txt exclusion standard.
+type RobotsTxt struct {
+	robotsDisabled bool
+	client         *client.Client
+	mut            sync.RWMutex
+	robotsMap      map[string]*robotstxt.RobotsData
+}
+
+func NewRobotsTxt(client *client.Client, robotsDisabled bool) RequestProcessor {
+	return &RobotsTxt{
+		robotsDisabled: robotsDisabled,
+		client:         client,
+		robotsMap:      make(map[string]*robotstxt.RobotsData),
+	}
+}
+
+func (m *RobotsTxt) ProcessRequest(r *client.Request) {
+	if m.robotsDisabled {
+		return
+	}
+
+	// TODO: Locking like this improves performance but causes duplicate requests to robots.txt,
+	m.mut.RLock()
+	robotsData, exists := m.robotsMap[r.Host]
+	m.mut.RUnlock()
+
+	if !exists {
+		// TODO: Disable retry
+		robotsReq, err := client.NewRequest("GET", r.URL.Scheme+"://"+r.Host+"/robots.txt", nil)
+		if err != nil {
+			return // Don't Do anything
+		}
+
+		robotsResp, err := m.client.DoRequestClient(robotsReq)
+		if err != nil {
+			return // Don't Do anything
+		}
+
+		robotsData, err = robotstxt.FromStatusAndBytes(robotsResp.StatusCode, robotsResp.Body)
+		if err != nil {
+			return // Don't Do anything
+		}
+
+		m.mut.Lock()
+		m.robotsMap[r.Host] = robotsData
+		m.mut.Unlock()
+	}
+
+	if !robotsData.TestAgent(r.URL.Path, r.UserAgent()) {
+		// TODO: Forbidden requests metrics
+		log.Println("Forbidden by robots.txt:", r.URL.String())
+		r.Cancel()
+	}
+}

options.go

@@ -15,48 +15,28 @@ type Options struct {
 	// If empty, any domain is allowed
 	AllowedDomains []string
 
-	// First requests will made to this url array. (Concurrently)
-	StartURLs []string
-
-	// StartRequestsFunc called on scraper start
-	StartRequestsFunc func(g *Geziyor)
-
-	// ParseFunc is callback of StartURLs response.
-	ParseFunc func(g *Geziyor, r *client.Response)
-
-	// Timeout is global request timeout
-	Timeout time.Duration
-
 	// Set this to enable caching responses.
 	// Memory Cache: httpcache.NewMemoryCache()
 	// Disk Cache:   diskcache.New(".cache")
 	Cache httpcache.Cache
 
+	// Charset Detection disable
+	CharsetDetectDisabled bool
+
 	// Concurrent requests limit
 	ConcurrentRequests int
+
 	// Concurrent requests per domain limit
 	ConcurrentRequestsPerDomain int
 
-	// User Agent.
-	// Default: "Geziyor 1.0"
-	UserAgent string
-
-	// Request delays
-	RequestDelay time.Duration
-	// RequestDelayRandomize uses random interval between 0.5 * RequestDelay and 1.5 * RequestDelay
-	RequestDelayRandomize bool
-
-	// Disable logging by setting this true
-	LogDisabled bool
+	// If set true, cookies won't send.
+	CookiesDisabled bool
 
 	// For extracting data
 	Exporters []export.Exporter
 
-	// Called before requests made to manipulate requests
-	RequestMiddlewares []middleware.RequestProcessor
-
-	// Called after response received
-	ResponseMiddlewares []middleware.ResponseProcessor
+	// Disable logging by setting this true
+	LogDisabled bool
 
 	// Max body reading size in bytes. Default: 1GB
 	MaxBodySize int64
@@ -64,27 +44,53 @@ type Options struct {
 	// Maximum redirection time. Default: 10
 	MaxRedirect int
 
-	// Charset Detection disable
-	CharsetDetectDisabled bool
+	// Scraper metrics exporting type. See metrics.Type
+	MetricsType metrics.Type
 
-	// Maximum number of times to retry, in addition to the first download.
-	// Set -1 to disable retrying
-	// Default: 2
-	RetryTimes int
+	// ParseFunc is callback of StartURLs response.
+	ParseFunc func(g *Geziyor, r *client.Response)
+
+	// If true, HTML parsing is disabled to improve performance.
+	ParseHTMLDisabled bool
+
+	// Request delays
+	RequestDelay time.Duration
+
+	// RequestDelayRandomize uses random interval between 0.5 * RequestDelay and 1.5 * RequestDelay
+	RequestDelayRandomize bool
+
+	// Called before requests made to manipulate requests
+	RequestMiddlewares []middleware.RequestProcessor
+
+	// Called after response received
+	ResponseMiddlewares []middleware.ResponseProcessor
 
 	// Which HTTP response codes to retry.
 	// Other errors (DNS lookup issues, connections lost, etc) are always retried.
 	// Default: []int{500, 502, 503, 504, 522, 524, 408}
 	RetryHTTPCodes []int
 
-	// If true, HTML parsing is disabled to improve performance.
-	ParseHTMLDisabled bool
+	// Maximum number of times to retry, in addition to the first download.
+	// Set -1 to disable retrying
+	// Default: 2
+	RetryTimes int
+
+	// If true, disable robots.txt checks
+	RobotsTxtDisabled bool
+
+	// StartRequestsFunc called on scraper start
+	StartRequestsFunc func(g *Geziyor)
+
+	// First requests will made to this url array. (Concurrently)
+	StartURLs []string
+
+	// Timeout is global request timeout
+	Timeout time.Duration
 
 	// Revisiting same URLs is disabled by default
 	URLRevisitEnabled bool
 
-	// If set true, cookies won't send.
-	CookiesDisabled bool
-
-	MetricsType metrics.Type
+	// User Agent.
+	// Default: "Geziyor 1.0"
+	UserAgent string
 }