behavior changes: UserAgent configurable, test cookies, check errors

fetch cookies from 1st response and use them in subsequent requests.

config.go

@@ -35,19 +35,27 @@ import (
 )
 
 const (
-	VERSION         string = "0.3.0"
+	VERSION    string = "0.3.1"
-	Baseuri         string = "https://www.kleinanzeigen.de"
+	Baseuri    string = "https://www.kleinanzeigen.de"
-	Listuri         string = "/s-bestandsliste.html"
+	Listuri    string = "/s-bestandsliste.html"
-	Defaultdir      string = "."
+	Defaultdir string = "."
+
 	DefaultTemplate string = "Title: {{.Title}}\nPrice: {{.Price}}\nId: {{.Id}}\n" +
 		"Category: {{.Category}}\nCondition: {{.Condition}}\n" +
 		"Created: {{.Created}}\nExpire: {{.Expire}}\n\n{{.Text}}\n"
+
 	DefaultTemplateWin string = "Title: {{.Title}}\r\nPrice: {{.Price}}\r\nId: {{.Id}}\r\n" +
 		"Category: {{.Category}}\r\nCondition: {{.Condition}}\r\n" +
 		"Created: {{.Created}}\r\nExpires: {{.Expire}}\r\n\r\n{{.Text}}\r\n"
-	Useragent string = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) " +
+
+	DefaultUserAgent string = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) " +
 		"AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"
+
 	DefaultAdNameTemplate string = "{{.Slug}}"
+
+	// for image download throttling
+	MinThrottle int = 2
+	MaxThrottle int = 20
 )
 
 const Usage string = `This is kleingebaeck, the kleinanzeigen.de backup tool.
@@ -84,6 +92,7 @@ type Config struct {
 	Limit            int    `koanf:"limit"`
 	IgnoreErrors     bool   `koanf:"ignoreerrors"`
 	ForceDownload    bool   `koanf:"force"`
+	UserAgent        string `koanf:"useragent"` // conf only
 	Adlinks          []string
 	StatsCountAds    int
 	StatsCountImages int
@@ -114,6 +123,7 @@ func InitConfig(w io.Writer) (*Config, error) {
 		"loglevel":       "notice",
 		"userid":         0,
 		"adnametemplate": DefaultAdNameTemplate,
+		"useragent":      DefaultUserAgent,
 	}, "."), nil); err != nil {
 		return nil, err
 	}

fetch.go

@@ -22,21 +22,32 @@ import (
 	"io"
 	"log/slog"
 	"net/http"
+	"net/http/cookiejar"
+	"net/url"
 )
 
 // convenient wrapper to fetch some web content
 type Fetcher struct {
-	Config    *Config
+	Config  *Config
-	Client    *http.Client
+	Client  *http.Client
-	Useragent string // FIXME: make configurable
+	Cookies []*http.Cookie
 }
 
-func NewFetcher(c *Config) *Fetcher {
+func NewFetcher(c *Config) (*Fetcher, error) {
-	return &Fetcher{
+	jar, err := cookiejar.New(nil)
-		Client:    &http.Client{Transport: &loggingTransport{}}, // implemented in http.go
+	if err != nil {
-		Useragent: Useragent,                                    // default in config.go
+		return nil, err
-		Config:    c,
 	}
+
+	return &Fetcher{
+			Client: &http.Client{
+				Transport: &loggingTransport{}, // implemented in http.go
+				Jar:       jar,
+			},
+			Config:  c,
+			Cookies: []*http.Cookie{},
+		},
+		nil
 }
 
 func (f *Fetcher) Get(uri string) (io.ReadCloser, error) {
@@ -45,7 +56,16 @@ func (f *Fetcher) Get(uri string) (io.ReadCloser, error) {
 		return nil, err
 	}
 
-	req.Header.Set("User-Agent", f.Useragent)
+	req.Header.Set("User-Agent", f.Config.UserAgent)
+
+	if len(f.Cookies) > 0 {
+		uriobj, _ := url.Parse(Baseuri)
+		slog.Debug("have cookies, sending them",
+			"sample-cookie-name", f.Cookies[0].Name,
+			"sample-cookie-expire", f.Cookies[0].Expires,
+		)
+		f.Client.Jar.SetCookies(uriobj, f.Cookies)
+	}
 
 	res, err := f.Client.Do(req)
 	if err != nil {
@@ -56,6 +76,9 @@ func (f *Fetcher) Get(uri string) (io.ReadCloser, error) {
 		return nil, errors.New("could not get page via HTTP")
 	}
 
+	slog.Debug("got cookies?", "cookies", res.Cookies())
+	f.Cookies = res.Cookies()
+
 	return res.Body, nil
 }
 

kleingebaeck.1

@@ -133,7 +133,7 @@
 .\" ========================================================================
 .\"
 .IX Title "KLEINGEBAECK 1"
-.TH KLEINGEBAECK 1 "2024-01-22" "1" "User Commands"
+.TH KLEINGEBAECK 1 "2024-01-24" "1" "User Commands"
 .\" For nroff, turn off justification.  Always turn off hyphenation; it makes
 .\" way too many mistakes in technical documents.
 .if n .ad l
@@ -174,10 +174,11 @@ well.   We    use   \s-1TOML\s0   as   our    configuration   language.   See
 .PP
 Format is pretty simple:
 .PP
-.Vb 10
+.Vb 11
 \&    user = 1010101
 \&    loglevel = verbose
 \&    outdir = "test"
+\&    useragent = "Mozilla/5.0"
 \&    template = """
 \&    Title: {{.Title}}
 \&    Price: {{.Price}}

kleingebaeck.go

@@ -39,6 +39,7 @@ CONFIGURATION
         user = 1010101
         loglevel = verbose
         outdir = "test"
+        useragent = "Mozilla/5.0"
         template = """
         Title: {{.Title}}
         Price: {{.Price}}

kleingebaeck.pod

@@ -39,6 +39,7 @@ Format is pretty simple:
     user = 1010101
     loglevel = verbose
     outdir = "test"
+    useragent = "Mozilla/5.0"
     template = """
     Title: {{.Title}}
     Price: {{.Price}}

main.go

@@ -22,8 +22,10 @@ import (
 	"fmt"
 	"io"
 	"log/slog"
+	"math/rand"
 	"os"
 	"runtime/debug"
+	"time"
 
 	"github.com/lmittmann/tint"
 	"github.com/tlinden/yadu"
@@ -111,7 +113,13 @@ func Main(w io.Writer) int {
 	}
 
 	// used for all HTTP requests
-	fetch := NewFetcher(conf)
+	fetch, err := NewFetcher(conf)
+	if err != nil {
+		return Die(err)
+	}
+
+	// randomization needed here and there
+	rand.Seed(time.Now().UnixNano())
 
 	if len(conf.Adlinks) >= 1 {
 		// directly backup ad listing[s]

main_test.go

@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"net/http"
 	"os"
 	"strings"
 	"testing"
@@ -446,19 +447,22 @@ func GetImage(path string) []byte {
 
 // setup httpmock
 func SetIntercept(ads []Adsource) {
+	ch := http.Header{}
+	ch.Add("Set-Cookie", "session=permanent")
+
 	for _, ad := range ads {
 		if ad.status == 0 {
 			ad.status = 200
 		}
 
 		httpmock.RegisterResponder("GET", ad.uri,
-			httpmock.NewStringResponder(ad.status, ad.content))
+			httpmock.NewStringResponder(ad.status, ad.content).HeaderAdd(ch))
 	}
 
 	// we just use 2 images, put this here
 	for _, image := range []string{"t/1.jpg", "t/2.jpg"} {
 		httpmock.RegisterResponder("GET", image,
-			httpmock.NewBytesResponder(200, GetImage(image)))
+			httpmock.NewBytesResponder(200, GetImage(image)).HeaderAdd(ch))
 	}
 
 }

scrape.go

@@ -24,6 +24,7 @@ import (
 	"log/slog"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"astuart.co/goq"
 	"golang.org/x/sync/errgroup"
@@ -150,6 +151,11 @@ func ScrapeImages(fetch *Fetcher, ad *Ad, addir string) error {
 		imguri := imguri
 		file := filepath.Join(adpath, fmt.Sprintf("%d.jpg", img))
 		g.Go(func() error {
+			// wait a little
+
+			t := GetThrottleTime()
+			time.Sleep(t)
+
 			body, err := fetch.Getimage(imguri)
 			if err != nil {
 				return err
@@ -163,7 +169,7 @@ func ScrapeImages(fetch *Fetcher, ad *Ad, addir string) error {
 
 			buf2 := buf.Bytes() // needed for image writing
 
-			image := NewImage(buf, "", imguri)
+			image := NewImage(buf, file, imguri)
 			err = image.CalcHash()
 			if err != nil {
 				return err
@@ -181,7 +187,7 @@ func ScrapeImages(fetch *Fetcher, ad *Ad, addir string) error {
 				return err
 			}
 
-			slog.Debug("wrote image", "image", image, "size", len(buf2))
+			slog.Debug("wrote image", "image", image, "size", len(buf2), "throttle", t)
 			return nil
 		})
 		img++

store_test.go

@@ -0,0 +1,37 @@
+/*
+Copyright © 2023-2024 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package main
+
+import (
+	"testing"
+)
+
+// this is  a weird thing.  WriteImage() is being called  in scrape.go
+// which is  being tested by  TestMain() in main_test.go.  However, it
+// doesn't  show up  in the  coverage report  for unknown  reasons, so
+// here's a single test for it
+func TestWriteImage(t *testing.T) {
+	buf := []byte{1, 2, 3, 4, 5, 6, 7, 8}
+	file := "t/out/t.jpg"
+
+	err := WriteImage(file, buf)
+	if err != nil {
+		t.Errorf("Could not write mock image to %s: %s", file, err.Error())
+	}
+
+}

util.go

@@ -20,9 +20,11 @@ package main
 import (
 	"bytes"
 	"errors"
+	"math/rand"
 	"os"
 	"os/exec"
 	"runtime"
+	"time"
 
 	"github.com/mattn/go-isatty"
 )
@@ -66,3 +68,7 @@ func IsNoTty() bool {
 	// it is a tty
 	return false
 }
+
+func GetThrottleTime() time.Duration {
+	return time.Duration(rand.Intn(MaxThrottle-MinThrottle+1)+MinThrottle) * time.Millisecond
+}