update yadu to v0.1.1, fix #46

* added environment variable support
* added docker instructions
* added .env hint

.github/workflows/pushimage.yaml

@@ -0,0 +1,28 @@
+name: build-push-image
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+jobs:
+  build-and-push-image:
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
+        with:
+          registry: https://ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@ad44023a93711e3deb337508980b4b5e9bcdc5dc
+        with:
+          push: true
+          tags: ghcr.io/tlinden/kleingebaeck:${{ github.ref_name}}

.gitignore

@@ -2,3 +2,4 @@ test
 kleingebaeck
 releases
 t/out
+.bak

Dockerfile

@@ -0,0 +1,27 @@
+FROM golang:1.21-alpine as builder
+
+RUN apk update
+RUN apk upgrade
+RUN apk add --no-cache git make
+
+RUN git --version
+
+WORKDIR /work
+
+COPY go.mod .
+COPY . .
+RUN go mod download
+RUN make
+
+FROM alpine:latest
+LABEL maintainer="Thomas von Dein <git@daemon.de>"
+
+WORKDIR /app
+COPY --from=builder /work/kleingebaeck /app/kleingebaeck
+
+ENV KLEINGEBAECK_OUTDIR /backup
+ENV LANG C.UTF-8
+USER 1001:1001
+
+ENTRYPOINT ["/app/kleingebaeck"]
+CMD ["-h"]

README.md

@@ -94,19 +94,48 @@ installed - `make`.
 
 To install after building either copy the binary or execute `sudo make install`.
 
+### Using the docker image
+
+A pre-built docker  image is available, which you can  use to test the
+app without  installing it. You  need `docker-compose`. Copy  the file
+`docker-compose.yaml` to somewhere, cd to that directory and execute:
+
+```shell
+mkdir kleinanzeigen-backup
+USER_ID=$(id -u) GROUP_ID=$(id -g) OUTDIR=./kleinanzeigen-backup docker-compose run kleingebaeck -u XXX -v
+```
+
+`USER_ID` and  `GROUP_ID` needs to  be specified  so that you  are the
+owner of the created backups. The backup directory `OUTDIR` must exist
+prior to the execution, otherwise docker  will create it as root, then
+kleingebaeck will  fail. You may  also use a  `.env` file in  the same
+directory containing the variables, such as:
+
+```
+USER_ID=1000
+GROUP_ID=1000
+OUTDIR=./kleinanzeigen-backup
+```
+
+You may of course also modify the `docker-compose.yaml` to suit your needs.
+
+If you want to build the image yourself, use the supplied Dockerfile.
+
 ## Commandline options:
 
 ```
 Usage: kleingebaeck [-dvVhmoc] [<ad-listing-url>,...]
 Options:
---user    -u <uid>      Backup ads from user with uid <uid>.
---debug   -d            Enable debug output.
---verbose -v            Enable verbose output.
---outdir  -o <dir>      Set output dir (default: current directory)
---limit   -l <num>      Limit the ads to download to <num>, default: load all.
---config  -c <file>     Use config file <file> (default: ~/.kleingebaeck).
---manual  -m            Show manual.
---help    -h            Show usage.
+-u --user    <uid>      Backup ads from user with uid <uid>.
+-d --debug              Enable debug output.
+-v --verbose            Enable verbose output.
+-o --outdir  <dir>      Set output dir (default: current directory)
+-l --limit   <num>      Limit the ads to download to <num>, default: load all.
+-c --config  <file>     Use config file <file> (default: ~/.kleingebaeck).
+   --ignoreerrors       Ignore HTTP errors, may lead to incomplete ad backup.
+-m --manual             Show manual.
+-h --help               Show usage.
+-V --version            Show program version.
 
 If one  or more <ad-listing-url>'s  are specified, only  backup those,
 otherwise backup all ads of the given user.
@@ -126,6 +155,13 @@ loglevel = verbose
 outdir = "test"
 ```
 
+## Environment Variables
+
+Kleingebaeck can also be configured using environment variables. Just prefix the config variables with `KLEINGEBAECK_` and put them to upper case. Eg:
+```shell
+% KLEINGEBAECK_OUTDIR=/backup kleingebaeck -v
+```
+
 ## Usage
 
 To setup the tool, you need to lookup your userid on

ad.go

@@ -20,6 +20,7 @@ package main
 import (
 	"log/slog"
 	"strings"
+	"time"
 )
 
 type Index struct {
@@ -37,6 +38,7 @@ type Ad struct {
 	Created      string   `goquery:"#viewad-extra-info,text"`
 	Text         string   `goquery:"p#viewad-description-text,html"`
 	Images       []string `goquery:".galleryimage-element img,[src]"`
+	Expire       string
 }
 
 // Used by slog to pretty print an ad
@@ -49,6 +51,8 @@ func (ad *Ad) LogValue() slog.Value {
 		slog.Int("bodysize", len(ad.Text)),
 		slog.String("categorytree", strings.Join(ad.CategoryTree, "+")),
 		slog.String("condition", ad.Condition),
+		slog.String("created", ad.Created),
+		slog.String("expire", ad.Expire),
 	)
 }
 
@@ -67,3 +71,12 @@ func (ad *Ad) Incomplete() bool {
 
 	return false
 }
+
+func (ad *Ad) CalculateExpire() {
+	if len(ad.Created) > 0 {
+		ts, err := time.Parse("02.01.2006", ad.Created)
+		if err == nil {
+			ad.Expire = ts.AddDate(0, 2, 1).Format("02.01.2006")
+		}
+	}
+}

config.go

@@ -23,9 +23,11 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"strings"
 
 	"github.com/knadh/koanf/parsers/toml"
 	"github.com/knadh/koanf/providers/confmap"
+	"github.com/knadh/koanf/providers/env"
 	"github.com/knadh/koanf/providers/file"
 	"github.com/knadh/koanf/providers/posflag"
 	"github.com/knadh/koanf/v2"
@@ -33,17 +35,19 @@ import (
 )
 
 const (
-	VERSION         string = "0.1.1"
+	VERSION         string = "0.2.0"
 	Baseuri         string = "https://www.kleinanzeigen.de"
 	Listuri         string = "/s-bestandsliste.html"
 	Defaultdir      string = "."
 	DefaultTemplate string = "Title: {{.Title}}\nPrice: {{.Price}}\nId: {{.Id}}\n" +
-		"Category: {{.Category}}\nCondition: {{.Condition}}\nCreated: {{.Created}}\n\n{{.Text}}\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\nCreated: {{.Created}}\r\n\r\n{{.Text}}\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) " +
 		"AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"
-	DefaultAdNameTemplate string = "{{.Slug}}-{{.Id}}"
+	DefaultAdNameTemplate string = "{{.Slug}}"
 )
 
 const Usage string = `This is kleingebaeck, the kleinanzeigen.de backup tool.
@@ -51,15 +55,17 @@ const Usage string = `This is kleingebaeck, the kleinanzeigen.de backup tool.
 Usage: kleingebaeck [-dvVhmoclu] [<ad-listing-url>,...]
 
 Options:
---user    -u <uid>      Backup ads from user with uid <uid>.
---debug   -d            Enable debug output.
---verbose -v            Enable verbose output.
---outdir  -o <dir>      Set output dir (default: current directory)
---limit   -l <num>      Limit the ads to download to <num>, default: load all.
---config  -c <file>     Use config file <file> (default: ~/.kleingebaeck).
---manual  -m            Show manual.
---help    -h            Show usage.
---version -V            Show program version.
+-u --user    <uid>      Backup ads from user with uid <uid>.
+-d --debug              Enable debug output.
+-v --verbose            Enable verbose output.
+-o --outdir  <dir>      Set output dir (default: current directory)
+-l --limit   <num>      Limit the ads to download to <num>, default: load all.
+-c --config  <file>     Use config file <file> (default: ~/.kleingebaeck).
+   --ignoreerrors       Ignore HTTP errors, may lead to incomplete ad backup.
+-f --force              Download images even if they already exist.
+-m --manual             Show manual.
+-h --help               Show usage.
+-V --version            Show program version.
 
 If one  or more ad listing url's  are specified, only  backup those,
 otherwise backup all ads of the given user.`
@@ -76,6 +82,8 @@ type Config struct {
 	Adnametemplate   string `koanf:"adnametemplate"`
 	Loglevel         string `koanf:"loglevel"`
 	Limit            int    `koanf:"limit"`
+	IgnoreErrors     bool   `koanf:"ignoreerrors"`
+	ForceDownload    bool   `koanf:"force"`
 	Adlinks          []string
 	StatsCountAds    int
 	StatsCountImages int
@@ -127,6 +135,7 @@ func InitConfig(w io.Writer) (*Config, error) {
 	f.BoolP("version", "V", false, "show program version")
 	f.BoolP("help", "h", false, "show usage")
 	f.BoolP("manual", "m", false, "show manual")
+	f.BoolP("force", "f", false, "force")
 
 	if err := f.Parse(os.Args[1:]); err != nil {
 		return nil, err
@@ -160,7 +169,15 @@ func InitConfig(w io.Writer) (*Config, error) {
 		// else: we ignore the file if it doesn't exists
 	}
 
-	// command line overrides config file
+	// env overrides config file
+	if err := k.Load(env.Provider("KLEINGEBAECK_", ".", func(s string) string {
+		return strings.Replace(strings.ToLower(
+			strings.TrimPrefix(s, "KLEINGEBAECK_")), "_", ".", -1)
+	}), nil); err != nil {
+		return nil, errors.New("error loading environment: " + err.Error())
+	}
+
+	// command line overrides env
 	if err := k.Load(posflag.Provider(f, ".", k), nil); err != nil {
 		return nil, errors.New("error loading flags: " + err.Error())
 	}

docker-compose.yaml

@@ -0,0 +1,22 @@
+version: "3.9"
+services:
+  init:
+    image: alpine:latest
+    user: "root"
+    group_add:
+      - '${GROUP_ID}'
+    volumes:
+      - ${OUTDIR}:/backup
+    command: chown -R ${USER_ID}:${USER_ID} /backup
+
+  kleingebaeck:
+    container_name: kleingebaeck
+    user: "${USER_ID}:${USER_ID}"
+    volumes:
+      - ${OUTDIR}:/backup
+    working_dir: /backup
+    build: .
+    image: kleingebaeck:latest
+    depends_on:
+      init:
+        condition: service_completed_successfully

fetch.go

@@ -0,0 +1,75 @@
+/*
+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 (
+	"errors"
+	"io"
+	"log/slog"
+	"net/http"
+)
+
+// convenient wrapper to fetch some web content
+type Fetcher struct {
+	Config    *Config
+	Client    *http.Client
+	Useragent string // FIXME: make configurable
+}
+
+func NewFetcher(c *Config) *Fetcher {
+	return &Fetcher{
+		Client:    &http.Client{Transport: &loggingTransport{}}, // implemented in http.go
+		Useragent: Useragent,                                    // default in config.go
+		Config:    c,
+	}
+}
+
+func (f *Fetcher) Get(uri string) (io.ReadCloser, error) {
+	req, err := http.NewRequest("GET", uri, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("User-Agent", f.Useragent)
+
+	res, err := f.Client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if res.StatusCode != 200 {
+		return nil, errors.New("could not get page via HTTP")
+	}
+
+	return res.Body, nil
+}
+
+// fetch an image
+func (f *Fetcher) Getimage(uri string) (io.ReadCloser, error) {
+	slog.Debug("fetching ad image", "uri", uri)
+	body, err := f.Get(uri)
+	if err != nil {
+		if f.Config.IgnoreErrors {
+			slog.Info("Failed to download image, error ignored", "error", err.Error())
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	return body, nil
+}

go.mod

@@ -7,25 +7,32 @@ require (
 	github.com/jarcoal/httpmock v1.3.1
 	github.com/knadh/koanf/parsers/toml v0.1.0
 	github.com/knadh/koanf/providers/confmap v0.1.0
+	github.com/knadh/koanf/providers/env v0.1.0
 	github.com/knadh/koanf/providers/file v0.1.0
 	github.com/knadh/koanf/providers/posflag v0.1.0
 	github.com/knadh/koanf/v2 v2.0.1
-	github.com/lmittmann/tint v1.0.3
+	github.com/lmittmann/tint v1.0.4
 	github.com/mattn/go-isatty v0.0.20
 	github.com/spf13/pflag v1.0.5
+	github.com/tlinden/yadu v0.1.1
 	golang.org/x/sync v0.5.0
 )
 
 require (
-	github.com/PuerkitoBio/goquery v1.5.0 // indirect
-	github.com/andybalholm/cascadia v1.0.0 // indirect
+	github.com/PuerkitoBio/goquery v1.5.1 // indirect
+	github.com/andybalholm/cascadia v1.1.0 // indirect
+	github.com/corona10/goimagehash v1.1.0 // indirect
+	github.com/fatih/color v1.16.0 // indirect
 	github.com/fsnotify/fsnotify v1.6.0 // indirect
 	github.com/knadh/koanf/maps v0.1.1 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 // indirect
 	github.com/pelletier/go-toml v1.9.5 // indirect
 	golang.org/x/net v0.0.0-20220722155237-a158d28d115b // indirect
-	golang.org/x/sys v0.6.0 // indirect
+	golang.org/x/sys v0.14.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 
 )

go.sum

@@ -1,12 +1,18 @@
 astuart.co/goq v1.0.0 h1:nnYIhu/Z/j0VaX9Dp+pmh2Uh7ldEz6XfgSg+bAY5Yrw=
 astuart.co/goq v1.0.0/go.mod h1:+fokcnFrO8Pw2fj8drdStJvzoMFebJH69rw8IC21rno=
-github.com/PuerkitoBio/goquery v1.5.0 h1:uGvmFXOA73IKluu/F84Xd1tt/z07GYm8X49XKHP7EJk=
 github.com/PuerkitoBio/goquery v1.5.0/go.mod h1:qD2PgZ9lccMbQlc7eEOjaeRlFQON7xY8kdmcsrnKqMg=
-github.com/andybalholm/cascadia v1.0.0 h1:hOCXnnZ5A+3eVDX8pvgl4kofXv2ELss0bKcqRySc45o=
+github.com/PuerkitoBio/goquery v1.5.1 h1:PSPBGne8NIUWw+/7vFBV+kG2J/5MOjbzc7154OaKCSE=
+github.com/PuerkitoBio/goquery v1.5.1/go.mod h1:GsLWisAFVj4WgDibEWF4pvYnkVQBpKBKeU+7zCJoLcc=
 github.com/andybalholm/cascadia v1.0.0/go.mod h1:GsXiBklL0woXo1j/WYWtSYYC4ouU9PqHO0sqidkEA4Y=
+github.com/andybalholm/cascadia v1.1.0 h1:BuuO6sSfQNFRu1LppgbD25Hr2vLYW25JvxHs5zzsLTo=
+github.com/andybalholm/cascadia v1.1.0/go.mod h1:GsXiBklL0woXo1j/WYWtSYYC4ouU9PqHO0sqidkEA4Y=
+github.com/corona10/goimagehash v1.1.0 h1:teNMX/1e+Wn/AYSbLHX8mj+mF9r60R1kBeqE9MkoYwI=
+github.com/corona10/goimagehash v1.1.0/go.mod h1:VkvE0mLn84L4aF8vCb6mafVajEb6QYMHl2ZJLn0mOGI=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fatih/color v1.16.0 h1:zmkK9Ngbjj+K0yRhTVONQh1p/HknKYSlNT+vZCzyokM=
+github.com/fatih/color v1.16.0/go.mod h1:fL2Sau1YI5c0pdGEVCbKQbLXB6edEj1ZgiY4NijnWvE=
 github.com/fsnotify/fsnotify v1.6.0 h1:n+5WquG0fcWoWp6xPWfHdbskMCQaFnG6PfBrh1Ky4HY=
 github.com/fsnotify/fsnotify v1.6.0/go.mod h1:sl3t1tCWJFWoRz9R8WJCbQihKKwmorjAbSClcnxKAGw=
 github.com/jarcoal/httpmock v1.3.1 h1:iUx3whfZWVf3jT01hQTO/Eo5sAYtB2/rqaUuOtpInww=
@@ -17,14 +23,19 @@ github.com/knadh/koanf/parsers/toml v0.1.0 h1:S2hLqS4TgWZYj4/7mI5m1CQQcWurxUz6OD
 github.com/knadh/koanf/parsers/toml v0.1.0/go.mod h1:yUprhq6eo3GbyVXFFMdbfZSo928ksS+uo0FFqNMnO18=
 github.com/knadh/koanf/providers/confmap v0.1.0 h1:gOkxhHkemwG4LezxxN8DMOFopOPghxRVp7JbIvdvqzU=
 github.com/knadh/koanf/providers/confmap v0.1.0/go.mod h1:2uLhxQzJnyHKfxG927awZC7+fyHFdQkd697K4MdLnIU=
+github.com/knadh/koanf/providers/env v0.1.0 h1:LqKteXqfOWyx5Ab9VfGHmjY9BvRXi+clwyZozgVRiKg=
+github.com/knadh/koanf/providers/env v0.1.0/go.mod h1:RE8K9GbACJkeEnkl8L/Qcj8p4ZyPXZIQ191HJi44ZaQ=
 github.com/knadh/koanf/providers/file v0.1.0 h1:fs6U7nrV58d3CFAFh8VTde8TM262ObYf3ODrc//Lp+c=
 github.com/knadh/koanf/providers/file v0.1.0/go.mod h1:rjJ/nHQl64iYCtAW2QQnF0eSmDEX/YZ/eNFj5yR6BvA=
 github.com/knadh/koanf/providers/posflag v0.1.0 h1:mKJlLrKPcAP7Ootf4pBZWJ6J+4wHYujwipe7Ie3qW6U=
 github.com/knadh/koanf/providers/posflag v0.1.0/go.mod h1:SYg03v/t8ISBNrMBRMlojH8OsKowbkXV7giIbBVgbz0=
 github.com/knadh/koanf/v2 v2.0.1 h1:1dYGITt1I23x8cfx8ZnldtezdyaZtfAuRtIFOiRzK7g=
 github.com/knadh/koanf/v2 v2.0.1/go.mod h1:ZeiIlIDXTE7w1lMT6UVcNiRAS2/rCeLn/GdLNvY1Dus=
-github.com/lmittmann/tint v1.0.3 h1:W5PHeA2D8bBJVvabNfQD/XW9HPLZK1XoPZH0cq8NouQ=
-github.com/lmittmann/tint v1.0.3/go.mod h1:HIS3gSy7qNwGCj+5oRjAutErFBl4BzdQP6cJZ0NfMwE=
+github.com/lmittmann/tint v1.0.4 h1:LeYihpJ9hyGvE0w+K2okPTGUdVLfng1+nDNVR4vWISc=
+github.com/lmittmann/tint v1.0.4/go.mod h1:HIS3gSy7qNwGCj+5oRjAutErFBl4BzdQP6cJZ0NfMwE=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/maxatome/go-testdeep v1.12.0 h1:Ql7Go8Tg0C1D/uMMX59LAoYK7LffeJQ6X2T04nTH68g=
@@ -35,6 +46,8 @@ github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyua
 github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
 github.com/mitchellh/reflectwalk v1.0.2 h1:G2LzWKi524PWgd3mLHV8Y5k7s6XUvT0Gef6zxSIeXaQ=
 github.com/mitchellh/reflectwalk v1.0.2/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/pelletier/go-toml v1.9.5 h1:4yBQzkHv+7BHq2PQUZF3Mx0IYxG7LsP222s7Agd3ve8=
 github.com/pelletier/go-toml v1.9.5/go.mod h1:u1nR/EPcESfeI/szUZKdtJ0xRNbUoANCkoOuaOx1Y+c=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -45,18 +58,29 @@ github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/tlinden/yadu v0.0.0-20240118202225-ec3f0b7fc355 h1:EmgK+IGUz2m42bFKteLY5SYJLn/CyBrz6nkgS22K8Bk=
+github.com/tlinden/yadu v0.0.0-20240118202225-ec3f0b7fc355/go.mod h1:l3bRmHKL9zGAR6pnBHY2HRPxBecf7L74BoBgOOpTcUA=
+github.com/tlinden/yadu v0.1.0 h1:qtCi1jxg392qVRLFyrJ2LYu6/PiKSp1LT02EX+mNLME=
+github.com/tlinden/yadu v0.1.0/go.mod h1:l3bRmHKL9zGAR6pnBHY2HRPxBecf7L74BoBgOOpTcUA=
+github.com/tlinden/yadu v0.1.1 h1:116oEUy9b4PcMF5wLL2dCFA/sn/praYutOnao07MROw=
+github.com/tlinden/yadu v0.1.1/go.mod h1:l3bRmHKL9zGAR6pnBHY2HRPxBecf7L74BoBgOOpTcUA=
 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=
 golang.org/x/net v0.0.0-20181114220301-adae6a3d119a/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190606173856-1492cefac77f/go.mod h1:HSz+uSET+XFnRR8LxR5pz3Of3rY3CfYBVs4xY44aLks=
+golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b h1:PxfKdU9lEEDYjdIzOtC4qFWgkU2rGHdKlKowJSMN9h0=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
 golang.org/x/sync v0.5.0 h1:60k92dhOjHxJkrqnwsfl8KuaHbn/5dl0lUPUklKo3qE=
 golang.org/x/sync v0.5.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220908164124-27713097b956/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.6.0 h1:MVltZSvRTcU2ljQOhs94SXPftV6DCNnZViHeQps87pQ=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.14.0 h1:Vz7Qs629MkJkGyHxUlRHizWJRG2j8fbQKjELVSNhy7Q=
+golang.org/x/sys v0.14.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

http.go

@@ -0,0 +1,129 @@
+/*
+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 (
+	"bytes"
+	"io"
+	"log/slog"
+	"math"
+	"math/rand"
+	"net/http"
+	"time"
+)
+
+// I add an artificial "ID" to each HTTP request and the corresponding
+// respose for  debugging purposes  so that  the pair  of them  can be
+// easier associated in debug output
+var letters = []rune("ABCDEF0123456789")
+
+func getid() string {
+	b := make([]rune, 8)
+	for i := range b {
+		b[i] = letters[rand.Intn(len(letters))]
+	}
+	return string(b)
+}
+
+// retry after HTTP 50x errors or err!=nil
+const RetryCount = 3
+
+// used to inject debug log and implement retries
+type loggingTransport struct{}
+
+// escalating timeout, $retry^2 seconds
+func backoff(retries int) time.Duration {
+	return time.Duration(math.Pow(2, float64(retries))) * time.Second
+}
+
+// only retry in case of errors or certain non 200 HTTP codes
+func shouldRetry(err error, resp *http.Response) bool {
+	if err != nil {
+		return true
+	}
+
+	if resp.StatusCode == http.StatusBadGateway ||
+		resp.StatusCode == http.StatusServiceUnavailable ||
+		resp.StatusCode == http.StatusGatewayTimeout {
+		return true
+	}
+
+	return false
+}
+
+// Body needs to be drained, otherwise we can't reuse the http.Response
+func drainBody(resp *http.Response) {
+	if resp != nil {
+		if resp.Body != nil {
+			_, err := io.Copy(io.Discard, resp.Body)
+			if err != nil {
+				// unable to copy data? uff!
+				panic(err)
+			}
+			resp.Body.Close()
+		}
+	}
+}
+
+// the actual logging transport with retries
+func (t *loggingTransport) RoundTrip(req *http.Request) (*http.Response, error) {
+	// just requred for debugging
+	id := getid()
+
+	// clone the request body, put into request on retry
+	var bodyBytes []byte
+	if req.Body != nil {
+		bodyBytes, _ = io.ReadAll(req.Body)
+		req.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
+	}
+
+	slog.Debug("REQUEST", "id", id, "uri", req.URL, "host", req.Host)
+
+	// first try
+	resp, err := http.DefaultTransport.RoundTrip(req)
+	if err == nil {
+		slog.Debug("RESPONSE", "id", id, "status", resp.StatusCode,
+			"contentlength", resp.ContentLength)
+	}
+
+	// enter retry check and loop, if first req were successfull, leave loop immediately
+	retries := 0
+	for shouldRetry(err, resp) && retries < RetryCount {
+		time.Sleep(backoff(retries))
+
+		// consume any response to reuse the connection.
+		drainBody(resp)
+
+		// clone the request body again
+		if req.Body != nil {
+			req.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
+		}
+
+		// actual retry
+		resp, err = http.DefaultTransport.RoundTrip(req)
+
+		if err == nil {
+			slog.Debug("RESPONSE", "id", id, "status", resp.StatusCode,
+				"contentlength", resp.ContentLength, "retry", retries)
+		}
+
+		retries++
+	}
+
+	return resp, err
+}

image.go

@@ -0,0 +1,142 @@
+/*
+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 (
+	"bytes"
+	"image/jpeg"
+	"log/slog"
+	"os"
+	"path/filepath"
+
+	"github.com/corona10/goimagehash"
+)
+
+const MaxDistance = 3
+
+type Image struct {
+	Filename string
+	Hash     *goimagehash.ImageHash
+	Data     *bytes.Buffer
+	Uri      string
+}
+
+// used for logging to avoid printing Data
+func (img *Image) LogValue() slog.Value {
+	return slog.GroupValue(
+		slog.String("filename", img.Filename),
+		slog.String("uri", img.Uri),
+		slog.String("hash", img.Hash.ToString()),
+	)
+}
+
+// holds all images of an ad
+type Cache []*goimagehash.ImageHash
+
+func NewImage(buf *bytes.Buffer, filename string, uri string) *Image {
+	img := &Image{
+		Filename: filename,
+		Uri:      uri,
+		Data:     buf,
+	}
+
+	return img
+}
+
+// Calculate diff hash of the image
+func (img *Image) CalcHash() error {
+	jpgdata, err := jpeg.Decode(img.Data)
+	if err != nil {
+		return err
+	}
+
+	hash1, err := goimagehash.DifferenceHash(jpgdata)
+	if err != nil {
+		return err
+	}
+
+	img.Hash = hash1
+
+	return nil
+}
+
+// checks if 2 images are similar enough to be considered the same
+func (img *Image) Similar(hash *goimagehash.ImageHash) bool {
+	distance, err := img.Hash.Distance(hash)
+	if err != nil {
+		slog.Debug("failed to compute diff hash distance", "error", err)
+		return false
+	}
+
+	if distance < MaxDistance {
+		slog.Debug("distance computation", "image-A", img.Hash.ToString(),
+			"image-B", hash.ToString(), "distance", distance)
+		return true
+	} else {
+		return false
+	}
+}
+
+// check current image against all known hashes.
+func (img *Image) SimilarExists(cache Cache) bool {
+	for _, otherimg := range cache {
+		if img.Similar(otherimg) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// read all  JPG images  in a  ad directory,  compute diff  hashes and
+// store the results in the slice Images
+func ReadImages(addir string, dont bool) (Cache, error) {
+	files, err := os.ReadDir(addir)
+	if err != nil {
+		return nil, err
+	}
+
+	cache := Cache{}
+
+	if dont {
+		// forced download, -f given
+		return cache, nil
+	}
+
+	for _, file := range files {
+		ext := filepath.Ext(file.Name())
+		if !file.IsDir() && (ext == ".jpg" || ext == ".jpeg" || ext == ".JPG" || ext == ".JPEG") {
+			filename := filepath.Join(addir, file.Name())
+			data, err := ReadImage(filename)
+			if err != nil {
+				return nil, err
+			}
+
+			img := NewImage(data, filename, "")
+			if err = img.CalcHash(); err != nil {
+				return nil, err
+			}
+
+			slog.Debug("Caching image from file system", "image", img, "hash", img.Hash.ToString())
+			cache = append(cache, img.Hash)
+		}
+	}
+
+	//return nil, errors.New("ende")
+	return cache, nil
+}

kleingebaeck.1

@@ -133,7 +133,7 @@
 .\" ========================================================================
 .\"
 .IX Title "KLEINGEBAECK 1"
-.TH KLEINGEBAECK 1 "2024-01-12" "1" "User Commands"
+.TH KLEINGEBAECK 1 "2024-01-22" "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
@@ -142,18 +142,20 @@
 kleingebaeck \- kleinanzeigen.de backup tool
 .SH "SYNOPSYS"
 .IX Header "SYNOPSYS"
-.Vb 11
+.Vb 10
 \&    Usage: kleingebaeck [\-dvVhmoc] [<ad\-listing\-url>,...]
 \&    Options:
-\&    \-\-user    \-u <uid>      Backup ads from user with uid <uid>.
-\&    \-\-debug   \-d            Enable debug output.
-\&    \-\-verbose \-v            Enable verbose output.
-\&    \-\-outdir  \-o <dir>      Set output dir (default: current directory)
-\&    \-\-limit   \-l <num>      Limit the ads to download to <num>, default: load all.
-\&    \-\-config  \-c <file>     Use config file <file> (default: ~/.kleingebaeck).
-\&    \-\-manual  \-m            Show manual.
-\&    \-\-help    \-h            Show usage.
-\&    \-\-version \-V            Show program version.
+\&    \-u \-\-user    <uid>      Backup ads from user with uid <uid>.
+\&    \-d \-\-debug              Enable debug output.
+\&    \-v \-\-verbose            Enable verbose output.
+\&    \-o \-\-outdir  <dir>      Set output dir (default: current directory)
+\&    \-l \-\-limit   <num>      Limit the ads to download to <num>, default: load all.
+\&    \-c \-\-config  <file>     Use config file <file> (default: ~/.kleingebaeck).
+\&       \-\-ignoreerrors       Ignore HTTP errors, may lead to incomplete ad backup.
+\&    \-f \-\-force              Download images even if they already exist.
+\&    \-m \-\-manual             Show manual.
+\&    \-h \-\-help               Show usage.
+\&    \-V \-\-version            Show program version.
 .Ve
 .SH "DESCRIPTION"
 .IX Header "DESCRIPTION"
@@ -218,6 +220,22 @@ directory. Then just execute \f(CW\*(C`kleingebaeck\*(C'\fR.
 .PP
 You can use the \fB\-v\fR option to  get verbose output or \fB\-d\fR to enable
 debugging.
+.SH "ENVIRONMENT VARIABLES"
+.IX Header "ENVIRONMENT VARIABLES"
+The following environment variables  are considered:
+.PP
+.Vb 7
+\&    KLEINGEBAECK_USER
+\&    KLEINGEBAECK_DEBUG
+\&    KLEINGEBAECK_VERBOSE
+\&    KLEINGEBAECK_OUTDIR
+\&    KLEINGEBAECK_LIMIT
+\&    KLEINGEBAECK_CONFIG
+\&    KLEINGEBAECK_IGNOREERRORS
+.Ve
+.PP
+Please  note,  that  they  take   precedence  over  config  file,  but
+commandline flags take precedence over env!
 .SH "BUGS"
 .IX Header "BUGS"
 In order to report a bug, unexpected behavior, feature requests

kleingebaeck.go

@@ -7,15 +7,17 @@ NAME
 SYNOPSYS
         Usage: kleingebaeck [-dvVhmoc] [<ad-listing-url>,...]
         Options:
-        --user    -u <uid>      Backup ads from user with uid <uid>.
-        --debug   -d            Enable debug output.
-        --verbose -v            Enable verbose output.
-        --outdir  -o <dir>      Set output dir (default: current directory)
-        --limit   -l <num>      Limit the ads to download to <num>, default: load all.
-        --config  -c <file>     Use config file <file> (default: ~/.kleingebaeck).
-        --manual  -m            Show manual.
-        --help    -h            Show usage.
-        --version -V            Show program version.
+        -u --user    <uid>      Backup ads from user with uid <uid>.
+        -d --debug              Enable debug output.
+        -v --verbose            Enable verbose output.
+        -o --outdir  <dir>      Set output dir (default: current directory)
+        -l --limit   <num>      Limit the ads to download to <num>, default: load all.
+        -c --config  <file>     Use config file <file> (default: ~/.kleingebaeck).
+           --ignoreerrors       Ignore HTTP errors, may lead to incomplete ad backup.
+        -f --force              Download images even if they already exist.
+        -m --manual             Show manual.
+        -h --help               Show usage.
+        -V --version            Show program version.
 
 DESCRIPTION
     This tool can be used to backup ads on the german ad page
@@ -73,6 +75,20 @@ SETUP
     You can use the -v option to get verbose output or -d to enable
     debugging.
 
+ENVIRONMENT VARIABLES
+    The following environment variables are considered:
+
+        KLEINGEBAECK_USER
+        KLEINGEBAECK_DEBUG
+        KLEINGEBAECK_VERBOSE
+        KLEINGEBAECK_OUTDIR
+        KLEINGEBAECK_LIMIT
+        KLEINGEBAECK_CONFIG
+        KLEINGEBAECK_IGNOREERRORS
+
+    Please note, that they take precedence over config file, but commandline
+    flags take precedence over env!
+
 BUGS
     In order to report a bug, unexpected behavior, feature requests or to
     submit a patch, please open an issue on github:

kleingebaeck.pod

@@ -6,15 +6,17 @@ kleingebaeck - kleinanzeigen.de backup tool
     
     Usage: kleingebaeck [-dvVhmoc] [<ad-listing-url>,...]
     Options:
-    --user    -u <uid>      Backup ads from user with uid <uid>.
-    --debug   -d            Enable debug output.
-    --verbose -v            Enable verbose output.
-    --outdir  -o <dir>      Set output dir (default: current directory)
-    --limit   -l <num>      Limit the ads to download to <num>, default: load all.
-    --config  -c <file>     Use config file <file> (default: ~/.kleingebaeck).
-    --manual  -m            Show manual.
-    --help    -h            Show usage.
-    --version -V            Show program version.
+    -u --user    <uid>      Backup ads from user with uid <uid>.
+    -d --debug              Enable debug output.
+    -v --verbose            Enable verbose output.
+    -o --outdir  <dir>      Set output dir (default: current directory)
+    -l --limit   <num>      Limit the ads to download to <num>, default: load all.
+    -c --config  <file>     Use config file <file> (default: ~/.kleingebaeck).
+       --ignoreerrors       Ignore HTTP errors, may lead to incomplete ad backup.
+    -f --force              Download images even if they already exist.
+    -m --manual             Show manual.
+    -h --help               Show usage.
+    -V --version            Show program version.
 
 =head1 DESCRIPTION
 
@@ -76,6 +78,23 @@ directory. Then just execute C<kleingebaeck>.
 You can use the B<-v> option to  get verbose output or B<-d> to enable
 debugging.
 
+=head1 ENVIRONMENT VARIABLES
+
+The following environment variables  are considered:
+
+    KLEINGEBAECK_USER
+    KLEINGEBAECK_DEBUG
+    KLEINGEBAECK_VERBOSE
+    KLEINGEBAECK_OUTDIR
+    KLEINGEBAECK_LIMIT
+    KLEINGEBAECK_CONFIG
+    KLEINGEBAECK_IGNOREERRORS
+
+Please  note,  that  they  take   precedence  over  config  file,  but
+commandline flags take precedence over env!
+
+
+
 =head1 BUGS
 
 In order to report a bug, unexpected behavior, feature requests

main.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2023 Thomas von Dein
+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
@@ -26,6 +26,7 @@ import (
 	"runtime/debug"
 
 	"github.com/lmittmann/tint"
+	"github.com/tlinden/yadu"
 )
 
 const LevelNotice = slog.Level(2)
@@ -84,14 +85,14 @@ func Main(w io.Writer) int {
 	if conf.Debug {
 		// we're using a more verbose logger in debug mode
 		buildInfo, _ := debug.ReadBuildInfo()
-		opts := &tint.Options{
+		opts := &yadu.Options{
 			Level:     logLevel,
 			AddSource: true,
-			NoColor:   IsNoTty(),
+			//NoColor:   IsNoTty(),
 		}
 
 		logLevel.Set(slog.LevelDebug)
-		handler := tint.NewHandler(w, opts)
+		handler := yadu.NewHandler(w, opts)
 		debuglogger := slog.New(handler).With(
 			slog.Group("program_info",
 				slog.Int("pid", os.Getpid()),
@@ -101,8 +102,6 @@ func Main(w io.Writer) int {
 		slog.SetDefault(debuglogger)
 	}
 
-	// defaultlogger := log.Default()
-	// defaultlogger.SetOutput(w)
 	slog.Debug("config", "conf", conf)
 
 	// prepare output dir
@@ -111,17 +110,20 @@ func Main(w io.Writer) int {
 		return Die(err)
 	}
 
+	// used for all HTTP requests
+	fetch := NewFetcher(conf)
+
 	if len(conf.Adlinks) >= 1 {
 		// directly backup ad listing[s]
 		for _, uri := range conf.Adlinks {
-			err := Scrape(conf, uri)
+			err := ScrapeAd(fetch, uri)
 			if err != nil {
 				return Die(err)
 			}
 		}
 	} else if conf.User > 0 {
 		// backup all ads of the given user (via config or cmdline)
-		err := Start(conf)
+		err := ScrapeUser(fetch)
 		if err != nil {
 			return Die(err)
 		}

main_test.go

@@ -114,6 +114,7 @@ const EMPTYPAGE string = `DOCTYPE html>
 
 const (
 	EMPTYURI       string = `https://www.kleinanzeigen.de/s-anzeige/empty/1`
+	INVALID503URI  string = `https://www.kleinanzeigen.de/s-anzeige/503/1`
 	INVALIDPATHURI string = `https://www.kleinanzeigen.de/anzeige/name/1`
 	INVALID404URI  string = `https://www.kleinanzeigen.de/anzeige/name/1/foo/bar`
 	INVALIDURI     string = `https://foo.bar/weird/things`
@@ -144,7 +145,13 @@ var tests = []Tests{
 	{
 		name:     "debug",
 		args:     base + " -d",
-		expect:   "program_info",
+		expect:   "error: invalid or no user id or no ad link specified",
+		exitcode: 1,
+	},
+	{
+		name:     "debug-check-programinfo",
+		args:     base + " -d",
+		expect:   "pid:",
 		exitcode: 1,
 	},
 	{
@@ -168,7 +175,7 @@ var tests = []Tests{
 	{
 		name:     "download-single-ad-debug",
 		args:     base + " -o t/out https://www.kleinanzeigen.de/s-anzeige/first-ad/1 -d",
-		expect:   "extracted ad listing program_info.pid=",
+		expect:   "DEBUG: extracted ad listing",
 		exitcode: 0,
 	},
 	{
@@ -228,6 +235,12 @@ var invalidtests = []Tests{
 		expect:   "error loading config file",
 		exitcode: 1,
 	},
+	{
+		name:     "503",
+		args:     base + " " + INVALID503URI,
+		expect:   "could not get page via HTTP",
+		exitcode: 1,
+	},
 }
 
 type AdConfig struct {
@@ -410,6 +423,12 @@ func InitInvalidSources() []Adsource {
 			content: GetTemplate(nil, empty, "<html>HTTP 404: /eine-anzeige/ does not exist!</html>"),
 			status:  404,
 		},
+		{
+			// valid ad page but 503
+			uri:     fmt.Sprintf("%s/s-anzeige/503/1", Baseuri),
+			content: GetTemplate(nil, empty, "<html>HTTP 503: service unavailable</html>"),
+			status:  503,
+		},
 	}
 
 	return ads
@@ -438,16 +457,18 @@ func SetIntercept(ads []Adsource) {
 
 	// 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.RegisterResponder("GET", image,
+			httpmock.NewBytesResponder(200, GetImage(image)))
 	}
 
 }
 
 func VerifyAd(ad AdConfig) error {
-	body := ad.Title + ad.Price + ad.Id + "Kleinanzeigen => " + ad.Category + ad.Condition + ad.Created
+	body := ad.Title + ad.Price + ad.Id + "Kleinanzeigen => " +
+		ad.Category + ad.Condition + ad.Created
 
 	// prepare ad dir name using DefaultAdNameTemplate
-	c := Config{Adnametemplate: DefaultAdNameTemplate}
+	c := Config{Adnametemplate: "{{ .Slug }}"}
 	adstruct := Ad{Slug: ad.Slug, Id: ad.Id}
 	addir, err := AdDirName(&c, &adstruct)
 	if err != nil {

scrape.go

@@ -18,11 +18,10 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package main
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
-	"io"
 	"log/slog"
-	"net/http"
 	"path/filepath"
 	"strings"
 
@@ -30,46 +29,21 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-// fetch some web page content
-func Get(uri string, client *http.Client) (io.ReadCloser, error) {
-	req, err := http.NewRequest("GET", uri, nil)
-	if err != nil {
-		return nil, err
-	}
-
-	req.Header.Set("User-Agent", Useragent)
-
-	res, err := client.Do(req)
-	if err != nil {
-		return nil, err
-	}
-
-	slog.Debug("response", "code", res.StatusCode, "status",
-		res.Status, "size", res.ContentLength)
-
-	if res.StatusCode != 200 {
-		return nil, errors.New("could not get page via HTTP")
-	}
-
-	return res.Body, nil
-}
-
 // extract links from  all ad listing pages (that  is: use pagination)
 // and scrape every page
-func Start(conf *Config) error {
-	client := &http.Client{}
+func ScrapeUser(fetch *Fetcher) error {
 	adlinks := []string{}
 
-	baseuri := fmt.Sprintf("%s%s?userId=%d", Baseuri, Listuri, conf.User)
+	baseuri := fmt.Sprintf("%s%s?userId=%d", Baseuri, Listuri, fetch.Config.User)
 	page := 1
 	uri := baseuri
 
-	slog.Info("fetching ad pages", "user", conf.User)
+	slog.Info("fetching ad pages", "user", fetch.Config.User)
 
 	for {
 		var index Index
 		slog.Debug("fetching page", "uri", uri)
-		body, err := Get(uri, client)
+		body, err := fetch.Get(uri)
 		if err != nil {
 			return err
 		}
@@ -96,12 +70,12 @@ func Start(conf *Config) error {
 	}
 
 	for i, adlink := range adlinks {
-		err := Scrape(conf, Baseuri+adlink)
+		err := ScrapeAd(fetch, Baseuri+adlink)
 		if err != nil {
 			return err
 		}
 
-		if conf.Limit > 0 && i == conf.Limit-1 {
+		if fetch.Config.Limit > 0 && i == fetch.Config.Limit-1 {
 			break
 		}
 	}
@@ -110,8 +84,7 @@ func Start(conf *Config) error {
 }
 
 // scrape an ad. uri is the full uri of the ad, dir is the basedir
-func Scrape(c *Config, uri string) error {
-	client := &http.Client{}
+func ScrapeAd(fetch *Fetcher, uri string) error {
 	ad := &Ad{}
 
 	// extract slug and id from uri
@@ -124,7 +97,7 @@ func Scrape(c *Config, uri string) error {
 
 	// get the ad
 	slog.Debug("fetching ad page", "uri", uri)
-	body, err := Get(uri, client)
+	body, err := fetch.Get(uri)
 	if err != nil {
 		return err
 	}
@@ -145,34 +118,70 @@ func Scrape(c *Config, uri string) error {
 		return errors.New("could not extract ad data from page, got empty struct")
 	}
 
-	slog.Debug("extracted ad listing", "ad", ad)
+	ad.CalculateExpire()
 
 	// write listing
-	addir, err := WriteAd(c, ad)
+	addir, err := WriteAd(fetch.Config, ad)
 	if err != nil {
 		return err
 	}
 
-	c.IncrAds()
+	slog.Debug("extracted ad listing", "ad", ad)
 
-	return ScrapeImages(c, ad, addir)
+	fetch.Config.IncrAds()
+
+	return ScrapeImages(fetch, ad, addir)
 }
 
-func ScrapeImages(c *Config, ad *Ad, addir string) error {
+func ScrapeImages(fetch *Fetcher, ad *Ad, addir string) error {
 	// fetch images
 	img := 1
+	adpath := filepath.Join(fetch.Config.Outdir, addir)
+
+	// scan existing images, if any
+	cache, err := ReadImages(adpath, fetch.Config.ForceDownload)
+	if err != nil {
+		return err
+	}
+
 	g := new(errgroup.Group)
 
 	for _, imguri := range ad.Images {
 		imguri := imguri
-		file := filepath.Join(c.Outdir, addir, fmt.Sprintf("%d.jpg", img))
+		file := filepath.Join(adpath, fmt.Sprintf("%d.jpg", img))
 		g.Go(func() error {
-			err := Getimage(imguri, file)
+			body, err := fetch.Getimage(imguri)
 			if err != nil {
 				return err
 			}
-			slog.Info("wrote ad image", "image", file)
 
+			buf := new(bytes.Buffer)
+			_, err = buf.ReadFrom(body)
+			if err != nil {
+				return err
+			}
+
+			buf2 := buf.Bytes() // needed for image writing
+
+			image := NewImage(buf, "", imguri)
+			err = image.CalcHash()
+			if err != nil {
+				return err
+			}
+
+			if !fetch.Config.ForceDownload {
+				if image.SimilarExists(cache) {
+					slog.Debug("similar image exists, not written", "uri", image.Uri)
+					return nil
+				}
+			}
+
+			err = WriteImage(file, buf2)
+			if err != nil {
+				return err
+			}
+
+			slog.Debug("wrote image", "image", image, "size", len(buf2))
 			return nil
 		})
 		img++
@@ -182,28 +191,7 @@ func ScrapeImages(c *Config, ad *Ad, addir string) error {
 		return err
 	}
 
-	c.IncrImgs(len(ad.Images))
-
-	return nil
-}
-
-// fetch an image
-func Getimage(uri, fileName string) error {
-	slog.Debug("fetching ad image", "uri", uri)
-	response, err := http.Get(uri)
-	if err != nil {
-		return err
-	}
-	defer response.Body.Close()
-
-	if response.StatusCode != 200 {
-		return errors.New("could not get image via HTTP")
-	}
-
-	err = WriteImage(fileName, response.Body)
-	if err != nil {
-		return err
-	}
+	fetch.Config.IncrImgs(len(ad.Images))
 
 	return nil
 }

store.go

@@ -19,7 +19,7 @@ package main
 
 import (
 	"bytes"
-	"io"
+	"fmt"
 	"log/slog"
 	"os"
 	"path/filepath"
@@ -86,17 +86,46 @@ func WriteAd(c *Config, ad *Ad) (string, error) {
 	return addir, nil
 }
 
-func WriteImage(filename string, reader io.ReadCloser) error {
+func WriteImage(filename string, buf []byte) error {
 	file, err := os.Create(filename)
 	if err != nil {
 		return err
 	}
 	defer file.Close()
 
-	_, err = io.Copy(file, reader)
+	_, err = file.Write(buf)
+
 	if err != nil {
 		return err
 	}
 
 	return nil
 }
+
+func ReadImage(filename string) (*bytes.Buffer, error) {
+	var buf bytes.Buffer
+
+	if !fileExists(filename) {
+		return nil, fmt.Errorf("image %s does not exist", filename)
+	}
+
+	data, err := os.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	_, err = buf.Write(data)
+	if err != nil {
+		return nil, err
+	}
+
+	return &buf, nil
+}
+
+func fileExists(filename string) bool {
+	info, err := os.Stat(filename)
+	if os.IsNotExist(err) {
+		return false
+	}
+	return !info.IsDir()
+}