Added /v2 in module name.

LICENSE

@@ -1,6 +1,6 @@
 The MIT License
 
-Copyright (c) 2022 Alexander "Arav" Andreev <me@arav.top>
+Copyright (c) 2022,2023 Alexander "Arav" Andreev <me@arav.su>
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

Makefile

@@ -1,31 +0,0 @@
-PACKAGE_NAME=justcaptcha
-TARGET=${PACKAGE_NAME}d
-
-SYSCTL=${shell which systemctl}
-SYSDDIR_=${shell pkg-config systemd --variable=systemdsystemunitdir}
-SYSDDIR=${SYSDDIR_:/%=%}
-DESTDIR=/
-
-LDFLAGS=-ldflags "-s -w -X main.version=2.0.0" -tags osusergo,netgo
-
-all: ${TARGET}
-
-.PHONY: ${TARGET}
-
-${TARGET}:
-	go build -o bin/$@ ${LDFLAGS} cmd/$@/main.go
-
-run:
-	bin/${TARGET} -expiry 1m -listen 127.0.0.1:19134
-
-install:
-	install -Dm 0755 bin/${TARGET} ${DESTDIR}usr/bin/${TARGET}
-	install -Dm 0644 LICENSE ${DESTDIR}usr/share/licenses/${PACKAGE_NAME}/LICENSE
-
-	install -Dm 0644 init/systemd/${PACKAGE_NAME}.service ${DESTDIR}${SYSDDIR}/${PACKAGE_NAME}.service
-
-uninstall:
-	rm ${DESTDIR}usr/bin/${TARGET}
-	rm ${DESTDIR}usr/share/licenses/${PACKAGE_NAME}/LICENSE
-
-	rm ${DESTDIR}${SYSDDIR}/${PACKAGE_NAME}.service

README.md

@@ -1,98 +1,36 @@
-justcaptcha ver. 2.0.0
-======================
+justcaptcha
+===========
 
-A simple CAPTCHA service implementation.
+A simple CAPTCHA implementation.
 
-## Usage
+An example using built-in "dwelling" implementation.
 
-    justcaptchad -expiry 5m -listen /var/run/justcaptcha/c.sock
+Create a new CAPTCHA:
 
-`-expiry` takes time for CAPTCHA to be valid for in format X{s,m,h}.
+    c := dwcaptcha.NewDwellingCaptcha(expiry)
+    _, id := inmemdb.New(someAdditionalDataUsedInIDGenerationUsuallyIPAddr, c)
 
-`-listen` is `ip:port` or `/path/to/unix.sock` to listen on.
+Get an image for a CAPTCHA:
 
-## API
+    i := inmemdb.Image(captchaID, captchaStyle)
+    if i == nil {
+        ... // do something if there was no image returned
+    }
 
-### Errors
+    jpeg.Encode(w, *i, &jpeg.Options{Quality: 20})
 
-All error codes are returned with an error message in `text/plain`.
+Solve a CAPTCHA:
 
-### Create a new CAPTCHA
+    if ok := inmemdb.Solve(captchaID, answer); !ok {
+        ... // not solved
+    }
+    // solved
+    ...
 
-    POST /
+Check is CAPTCHA was solved:
 
-It will return an ID of a new CAPTCHA in `text/plain`.
-
-#### HTTP codes
-- `201` if created (always being created)
-
-### Get an image for a CAPTCHA
-
-    GET /:captcha_id/image?style=
-
-Responds with an image in JPEG format (`image/jpeg`).
-
-An optional URL parameter `style=` set a name of a CAPTCHA style if it is
-implemented by used CAPTCHA implementation.
-
-#### HTTP codes
-- `200` if exists
-- `404` if doesn't exist
-- `500` if for some reason an image wasn't created
-
-### Submit an answer
-
-    POST /:captcha_id
-
-Accepts `application/x-www-form-urlencoded` content type.
-
-It takes one parameter `answer=123456`.
-
-Responds with an empty body and one of the HTTP codes.
-
-#### HTTP codes
-- `202` if solved
-- `403` if not solved
-
-### Check if captcha is solved
-
-    GET /:captcha_id?remove
-
-Responds with an empty body and one of the HTTP codes.
-
-If an optional `remove` parameter without a value supplied CAPTCHA will be
-removed without checking and a HTTP code `204` will be sent. Otherwise, a `403`
-HTTP code will be sent if it is not solved.
-
-A `remove` parameter was added because browsers will print an error in a console
-if HTTP code is not within `2xx`, so to keep a console clean you can provide
-this parameter.
-
-This can be useful to remove an unused CAPTCHA from a DB without waiting for it
-to be expired. E.g. when a visitor requests for a new CAPTCHA or leaving a page.
-
-#### HTTP codes
-- `204` if solved
-- `403` if not solved
-
-### Example of interaction
-
-First a client makes a POST request with empty body to create a new CAPTCHA and obtains an ID for it.
-
-    POST /
-
-As a result we get an ID `n60f2K9JiD5c4qX9MYe90A54nT0nnJrtgfhAjfaWtBg`.
-
-Then a client requests an image for a new CAPTCHA. E.g. with a dark style.
-
-    GET /n60f2K9JiD5c4qX9MYe90A54nT0nnJrtgfhAjfaWtBg/image?style=dark
-
-Then a client submits an answer for a CAPTCHA.
-
-    POST 'answer=198807' /n60f2K9JiD5c4qX9MYe90A54nT0nnJrtgfhAjfaWtBg
-
-And if answer was correct a client gets a HTTP code 202. Or 403 otherwise.
-
-Then a server checks if CAPTCHA was solved with following request.
-
-    GET /n60f2K9JiD5c4qX9MYe90A54nT0nnJrtgfhAjfaWtBg
+    if ok := inmemdb.IsSolved(captchaID); !ok {
+	    ... // not solved
+    }
+    // solved
+    ...

build/archlinux/PKGBUILD

@@ -1,30 +0,0 @@
-# Maintainer: Alexander "Arav" Andreev <me@arav.top>
-pkgname=justcaptcha
-pkgver=2.0.0
-pkgrel=1
-pkgdesc="Just a CAPTCHA service"
-arch=('i686' 'x86_64' 'arm' 'armv6h' 'armv7h' 'aarch64')
-url="https://git.arav.top/Arav/justcaptcha"
-license=('MIT')
-groups=()
-depends=()
-makedepends=('go')
-provides=('justcaptcha')
-conflicts=('justcaptcha')
-replaces=()
-backup=()
-options=()
-install=
-source=('https://git.arav.top/Arav/justcaptcha/archive/2.0.0.tar.gz')
-noextract=()
-md5sums=('SKIP')
-
-build() {
-    cd "$srcdir/$pkgname"
-    make DESTDIR="$pkgdir/"
-}
-
-package() {
-    cd "$srcdir/$pkgname"
-    make DESTDIR="$pkgdir/" install
-}

captcha.go

@@ -45,7 +45,7 @@ type BaseCaptcha struct {
 
 func NewBaseCaptcha(expiry time.Duration) *BaseCaptcha {
 	return &BaseCaptcha{
-		expiry: ExpiryDate(expiry),
+		expiry: time.Now().Add(expiry),
 	}
 }
 
@@ -72,9 +72,3 @@ func (c *BaseCaptcha) IsSolved() bool {
 func (c *BaseCaptcha) Expiry() time.Time {
 	return c.expiry
 }
-
-// ExpiryDate returns a date when CAPTCHA expires. It adds a passed
-// expiry duration to a current time.
-func ExpiryDate(expiry time.Duration) time.Time {
-	return time.Now().Add(expiry)
-}

cmd/justcaptchad/main.go

@@ -1,69 +0,0 @@
-package main
-
-import (
-	"flag"
-	"fmt"
-	"justcaptcha/internal/handlers"
-	"justcaptcha/pkg/server"
-	"log"
-	"net/netip"
-	"os"
-	"os/signal"
-	"strings"
-	"syscall"
-	"time"
-)
-
-var version string
-
-var listenAddress *string = flag.String("listen", "/var/run/justcaptcha/c.sock", "listen address (ip:port|unix_path)")
-var captchaExpiry *time.Duration = flag.Duration("expiry", 5*time.Minute, "CAPTCHA expiry in format XX{s,m,h}, e.g. 5m, 300s")
-var showVersion *bool = flag.Bool("v", false, "show version")
-
-func main() {
-	flag.Parse()
-	log.SetFlags(0)
-
-	if *showVersion {
-		fmt.Println("justcaptchad ver.", version, "\nCopyright (c) 2022 Alexander \"Arav\" Andreev <me@arav.top>")
-		return
-	}
-
-	hand := handlers.New(*captchaExpiry)
-	srv := server.NewHttpServer()
-
-	srv.POST("/", hand.New)
-	srv.POST("/:captcha", hand.Solve)
-	srv.GET("/:captcha", hand.IsSolved)
-	srv.GET("/:captcha/image", hand.Image)
-
-	var network string
-	if !strings.ContainsRune(*listenAddress, ':') {
-		network = "unix"
-		defer os.Remove(*listenAddress)
-	} else {
-		ap, err := netip.ParseAddrPort(*listenAddress)
-		if err != nil {
-			log.Fatalln(err)
-		}
-
-		if ap.Addr().Is4() {
-			network = "tcp4"
-		} else if ap.Addr().Is6() {
-			network = "tcp6"
-		}
-	}
-
-	if err := srv.Start(network, *listenAddress); err != nil {
-		log.Fatalln("failed to start a server:", err)
-	}
-
-	doneSignal := make(chan os.Signal, 1)
-	signal.Notify(doneSignal, os.Interrupt, syscall.SIGINT, syscall.SIGTERM)
-
-	<-doneSignal
-
-	if err := srv.Stop(); err != nil {
-		log.Fatalln("failed to properly shutdown a server:", err)
-	}
-}

db.go

@@ -30,8 +30,8 @@ func NewID(additionalData string, answer Answer) ID {
 	return ID(base64.RawURLEncoding.EncodeToString(idHash.Sum(nil)))
 }
 
-// CaptchaDB interface with all necessary methods.
-type CaptchaDB interface {
+// DB interface with all necessary methods.
+type DB interface {
 	New(data string, captcha Captcha) (Captcha, ID)
 	GetExpiry() time.Duration
 	SetExpiry(expiry time.Duration)

dwcaptcha/dwcaptcha_test.go

@@ -0,0 +1,30 @@
+package dwcaptcha_test
+
+import (
+	"testing"
+	"time"
+
+	"git.arav.su/Arav/justcaptcha/v2/dwcaptcha"
+)
+
+const expiry = 10 * time.Minute
+
+func TestCaptcha(t *testing.T) {
+	captcha := dwcaptcha.NewDwellingCaptcha(expiry)
+
+	if diff := time.Until(captcha.Expiry()) - expiry; diff >= 1*time.Microsecond {
+		t.Errorf("Difference %s is more than 1 microsecond", diff.String())
+	}
+
+	if captcha.Image("") == nil {
+		t.Error("image cannot be nil, but it is!")
+	}
+
+	if !captcha.Solve(captcha.Answer()) {
+		t.Error("for whatever reason, its own answer doesn't match itself O_O")
+	}
+
+	if !captcha.IsSolved() {
+		t.Error("after last test it should be true, but it is not!")
+	}
+}

dwcaptcha/dwelling_captcha.go

@@ -2,10 +2,11 @@ package dwcaptcha
 
 import (
 	"image"
-	"justcaptcha/pkg/captcha"
 	"math/rand"
 	"time"
 
+	captcha "git.arav.su/Arav/justcaptcha/v2"
+
 	"github.com/fogleman/gg"
 )
 

go.mod

@@ -1,13 +1,10 @@
-module justcaptcha
+module git.arav.su/Arav/justcaptcha/v2
 
-go 1.19
+go 1.12
 
-require (
-	github.com/fogleman/gg v1.3.0
-	github.com/julienschmidt/httprouter v1.3.0
-)
+require github.com/fogleman/gg v1.3.0
 
 require (
 	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 // indirect
-	golang.org/x/image v0.1.0 // indirect
+	golang.org/x/image v0.11.0 // indirect
 )

go.sum

@@ -2,31 +2,36 @@ github.com/fogleman/gg v1.3.0 h1:/7zJX8F6AaYQc57WQCyN9cAIz+4bCJGO9B+dyW29am8=
 github.com/fogleman/gg v1.3.0/go.mod h1:R/bRT+9gY/C5z7JzPU0zXsXHKM4/ayA+zqcVNZzPa1k=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k=
-github.com/julienschmidt/httprouter v1.3.0 h1:U0609e9tgbseu3rBINet9P48AI/D3oJs4dN7jwJOQ1U=
-github.com/julienschmidt/httprouter v1.3.0/go.mod h1:JR6WtHb+2LUe8TCKY3cZOxFyyO8IZAc4RVcycCCAKdM=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/image v0.1.0 h1:r8Oj8ZA2Xy12/b5KZYj3tuv7NG/fBz3TwQVvpJ9l8Rk=
-golang.org/x/image v0.1.0/go.mod h1:iyPr49SD/G/TBxYVB/9RRtGUT5eNbo2u4NamWeQcD5c=
+golang.org/x/image v0.11.0 h1:ds2RoQvBvYTiJkwpSFDwCcDFNX7DqjL2WsUgTNk0Ooo=
+golang.org/x/image v0.11.0/go.mod h1:bglhjqbqVuEb9e9+eNR45Jfu7D+T4Qan+NhQk8Ck2P8=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
+golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
+golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.12.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

init/systemd/justcaptcha.service

@@ -1,39 +0,0 @@
-[Unit]
-Description=A simple CAPTCHA service for your website
-After=network.target
-
-[Service]
-Type=simple
-Restart=on-failure
-DynamicUser=yes
-ExecStart=/usr/bin/justcaptchad -expiry 5m -listen /var/run/justcaptcha/j.sock
-
-ReadOnlyPaths=/
-# Set here path to directory where uploads are stored.
-NoExecPaths=/
-ExecPaths=/usr/bin/justcaptchad
-
-RuntimeDirectory=justcaptcha
-
-AmbientCapabilities=
-CapabilityBoundingSet=
-
-LockPersonality=true
-MemoryDenyWriteExecute=true
-NoNewPrivileges=true
-PrivateDevices=true
-ProtectClock=true
-ProtectControlGroups=true
-ProtectHome=true
-ProtectKernelLogs=true
-ProtectKernelModules=true
-ProtectKernelTunables=true
-ProtectSystem=strict
-RestrictAddressFamilies=AF_INET AF_INET6 AF_UNIX
-RestrictNamespaces=true
-RestrictRealtime=true
-RestrictSUIDSGID=true
-SystemCallArchitectures=native
-
-[Install]
-WantedBy=multi-user.target

inmemdb/inmemdb.go

@@ -2,12 +2,14 @@ package inmemdb
 
 import (
 	"image"
-	"justcaptcha/pkg/captcha"
 	"sync"
 	"time"
+
+	captcha "git.arav.su/Arav/justcaptcha/v2"
 )
 
-type InMemoryCaptchaDB struct {
+// InMemoryDB implementation that lives in a memory (map).
+type InMemoryDB struct {
 	sync.Mutex
 
 	db                 map[captcha.ID]captcha.Captcha
@@ -15,10 +17,11 @@ type InMemoryCaptchaDB struct {
 	expiryScanInterval time.Duration
 }
 
-// NewInMemoryCaptchaDB returns an initialised instance of an InMemoryCaptchaDB.
-// An expiry duration is a time for how long CAPTCHA will be valid.
-func NewInMemoryCaptchaDB(expiry time.Duration) *InMemoryCaptchaDB {
-	db := &InMemoryCaptchaDB{
+// NewInMemoryDB returns an initialised instance of an InMemoryDB.
+// An expiry is a scan interval for expired CAPTCHAs (if passed a longer one,
+// resets to a default (captcha.DefaultExpiredScanInterval)).
+func NewInMemoryDB(expiry time.Duration) *InMemoryDB {
+	db := &InMemoryDB{
 		db:     make(map[captcha.ID]captcha.Captcha),
 		expiry: expiry}
 
@@ -33,10 +36,10 @@ func NewInMemoryCaptchaDB(expiry time.Duration) *InMemoryCaptchaDB {
 	return db
 }
 
-// New accepts a CAPTHA instance, generates an ID and store it in a database.
+// New accepts a CAPTCHA instance, generates an ID and store it in a database.
 // A data string is an additional random data used to generate an ID,
 // e.g. an IP-address.
-func (imcdb *InMemoryCaptchaDB) New(data string, cptcha captcha.Captcha) (captcha.Captcha, captcha.ID) {
+func (imcdb *InMemoryDB) New(data string, cptcha captcha.Captcha) (captcha.Captcha, captcha.ID) {
 	id := captcha.NewID(data, cptcha.Answer())
 
 	imcdb.Lock()
@@ -46,13 +49,15 @@ func (imcdb *InMemoryCaptchaDB) New(data string, cptcha captcha.Captcha) (captch
 	return cptcha, id
 }
 
-// GetExpiry returns time for how long CAPTCHA will last.
-func (imcdb *InMemoryCaptchaDB) GetExpiry() time.Duration {
+// GetExpiry returns an expiry for a CAPTCHA.
+func (imcdb *InMemoryDB) GetExpiry() time.Duration {
 	return imcdb.expiry
 }
 
-// SetExpiry changes an expiry duration to a new one.
-func (imcdb *InMemoryCaptchaDB) SetExpiry(expiry time.Duration) {
+// SetExpiry changes an expiry for a CAPTCHA and a scan interval. Scan interval
+// cannot be longer than a default, so if it is, then resets to a default.
+func (imcdb *InMemoryDB) SetExpiry(expiry time.Duration) {
+	imcdb.expiry = expiry
 	if expiry < captcha.DefaultExpiredScanInterval {
 		imcdb.expiryScanInterval = expiry
 	} else {
@@ -60,8 +65,9 @@ func (imcdb *InMemoryCaptchaDB) SetExpiry(expiry time.Duration) {
 	}
 }
 
-// Image returns a freshly generated image for a CAPTCHA.
-func (imcdb *InMemoryCaptchaDB) Image(id captcha.ID, style string) *image.Image {
+// Image returns a freshly generated image for a CAPTCHA with style if
+// applicable.
+func (imcdb *InMemoryDB) Image(id captcha.ID, style string) *image.Image {
 	imcdb.Lock()
 	defer imcdb.Unlock()
 	if c, ok := imcdb.db[id]; ok {
@@ -72,7 +78,7 @@ func (imcdb *InMemoryCaptchaDB) Image(id captcha.ID, style string) *image.Image
 
 // Solve compares given answer with a stored one and if failed
 // deletes a CAPTCHA from database.
-func (imcdb *InMemoryCaptchaDB) Solve(id captcha.ID, answer captcha.Answer) bool {
+func (imcdb *InMemoryDB) Solve(id captcha.ID, answer captcha.Answer) bool {
 	imcdb.Lock()
 	defer imcdb.Unlock()
 	if c, ok := imcdb.db[id]; ok {
@@ -87,7 +93,7 @@ func (imcdb *InMemoryCaptchaDB) Solve(id captcha.ID, answer captcha.Answer) bool
 
 // IsSolved checks if CAPTCHA was solved and removes it
 // from a database.
-func (imcdb *InMemoryCaptchaDB) IsSolved(id captcha.ID) bool {
+func (imcdb *InMemoryDB) IsSolved(id captcha.ID) bool {
 	imcdb.Lock()
 	defer imcdb.Unlock()
 	if c, ok := imcdb.db[id]; ok {
@@ -98,16 +104,14 @@ func (imcdb *InMemoryCaptchaDB) IsSolved(id captcha.ID) bool {
 }
 
 // Remove a CAPTCHA from a database.
-func (imcdb *InMemoryCaptchaDB) Remove(id captcha.ID) {
+func (imcdb *InMemoryDB) Remove(id captcha.ID) {
 	imcdb.Lock()
 	defer imcdb.Unlock()
-	if _, ok := imcdb.db[id]; ok {
-		delete(imcdb.db, id)
-	}
+	delete(imcdb.db, id)
 }
 
 // cleanExpired removes expired CAPTCHAs in a loop.
-func (imcdb *InMemoryCaptchaDB) cleanExpired() {
+func (imcdb *InMemoryDB) cleanExpired() {
 	for {
 		sleepFor := imcdb.expiryScanInterval - (time.Duration(time.Now().Second()) % imcdb.expiryScanInterval)
 		time.Sleep(sleepFor)
@@ -122,9 +126,9 @@ func (imcdb *InMemoryCaptchaDB) cleanExpired() {
 	}
 }
 
-// An instance of InMemoryCaptchaDB
+// An instance of InMemoryDB
 
-var imcdb = NewInMemoryCaptchaDB(captcha.DefaultExpiredScanInterval)
+var imcdb = NewInMemoryDB(captcha.DefaultExpiredScanInterval)
 
 func GetExpiry() time.Duration {
 	return imcdb.GetExpiry()

inmemdb/inmemdb_test.go

@@ -0,0 +1,48 @@
+package inmemdb_test
+
+import (
+	"testing"
+	"time"
+
+	captcha "git.arav.su/Arav/justcaptcha/v2"
+	"git.arav.su/Arav/justcaptcha/v2/dwcaptcha"
+	"git.arav.su/Arav/justcaptcha/v2/inmemdb"
+)
+
+const expiry = 10 * time.Minute
+const testData = "192.168.0.1"
+
+func TestInMemDBDefaultInstance(t *testing.T) {
+	if inmemdb.GetExpiry() != captcha.DefaultExpiredScanInterval {
+		t.Errorf("expiration is different from a default one (%v != %v)",
+			inmemdb.GetExpiry(), captcha.DefaultExpiredScanInterval)
+	}
+
+	inmemdb.SetExpiry(expiry)
+
+	if expiry != inmemdb.GetExpiry() {
+		t.Errorf("Expected %v, but got %v", expiry, inmemdb.GetExpiry())
+	}
+
+	captcha, captchaID := inmemdb.New(testData, dwcaptcha.NewDwellingCaptcha(expiry))
+
+	if inmemdb.Image(captchaID, "") == nil {
+		t.Error("nil returned instead of an image.Image struct")
+	}
+
+	if !inmemdb.Solve(captchaID, captcha.Answer()) {
+		t.Error("CAPTCHA not solved. Looks like provided ID wasn't found")
+	}
+
+	if !inmemdb.IsSolved(captchaID) {
+		t.Error("last test solved a CAPTCHA, but IsSolved() returned false")
+	}
+}
+
+func TestInMemDBNewInstance(t *testing.T) {
+	db := inmemdb.NewInMemoryDB(expiry)
+
+	if db.GetExpiry() != expiry {
+		t.Errorf("expected expiry %v, but got %v", expiry, db.GetExpiry())
+	}
+}

internal/handlers/handlers.go

@@ -1,78 +0,0 @@
-package handlers
-
-import (
-	"fmt"
-	"image/jpeg"
-	"justcaptcha/internal/dwcaptcha"
-	"justcaptcha/pkg/captcha"
-	"justcaptcha/pkg/captcha/inmemdb"
-	"justcaptcha/pkg/server"
-	"net/http"
-	"time"
-)
-
-const errMsgWrongAnswer = "An answer provided was wrong"
-const errMsgImageNotFound = "cannot get an image for a non-existing CAPTCHA"
-
-type CaptchaHandlers struct {
-	expiry time.Duration
-}
-
-func New(expiry time.Duration) *CaptchaHandlers {
-	inmemdb.SetExpiry(expiry)
-	return &CaptchaHandlers{expiry: expiry}
-}
-
-func (h *CaptchaHandlers) New(w http.ResponseWriter, r *http.Request) {
-	dc := dwcaptcha.NewDwellingCaptcha(h.expiry)
-	_, id := inmemdb.New(r.RemoteAddr, dc)
-	w.WriteHeader(http.StatusCreated)
-	fmt.Fprint(w, id)
-}
-
-func (h *CaptchaHandlers) Image(w http.ResponseWriter, r *http.Request) {
-	captchaID := captcha.ID(server.GetURLParam(r, "captcha"))
-	captchaStyle := r.URL.Query().Get("style")
-
-	captchaImage := inmemdb.Image(captchaID, captchaStyle)
-	if captchaImage == nil {
-		http.Error(w, errMsgImageNotFound, http.StatusNotFound)
-		return
-	}
-
-	w.Header().Add("Content-Disposition", "inline; filename=\""+string(captchaID)+"\"")
-
-	jpeg.Encode(w, *captchaImage, &jpeg.Options{Quality: 20})
-}
-
-func (h *CaptchaHandlers) Solve(w http.ResponseWriter, r *http.Request) {
-	captchaID := captcha.ID(server.GetURLParam(r, "captcha"))
-
-	r.ParseForm()
-	answer := captcha.Answer(r.FormValue("answer"))
-
-	if ok := inmemdb.Solve(captchaID, answer); !ok {
-		http.Error(w, errMsgWrongAnswer, http.StatusForbidden)
-		return
-	}
-
-	w.WriteHeader(http.StatusAccepted)
-}
-
-func (h *CaptchaHandlers) IsSolved(w http.ResponseWriter, r *http.Request) {
-	captchaID := captcha.ID(server.GetURLParam(r, "captcha"))
-	isJustRemove := r.URL.Query().Has("remove")
-
-	if isJustRemove {
-		inmemdb.Remove(captchaID)
-		w.WriteHeader(http.StatusNoContent)
-		return
-	}
-
-	if solved := inmemdb.IsSolved(captchaID); !solved {
-		http.Error(w, errMsgWrongAnswer, http.StatusForbidden)
-		return
-	}
-
-	w.WriteHeader(http.StatusNoContent)
-}

pkg/server/http.go

@@ -1,76 +0,0 @@
-package server
-
-import (
-	"context"
-	"log"
-	"net"
-	"net/http"
-	"os"
-	"time"
-
-	"github.com/julienschmidt/httprouter"
-)
-
-type HttpServer struct {
-	server *http.Server
-	router *httprouter.Router
-}
-
-func NewHttpServer() *HttpServer {
-	r := httprouter.New()
-	return &HttpServer{
-		server: &http.Server{
-			ReadTimeout:  3 * time.Second,
-			WriteTimeout: 3 * time.Second,
-			Handler:      r,
-		},
-		router: r,
-	}
-}
-
-func (s *HttpServer) GET(path string, handler http.HandlerFunc) {
-	s.router.Handler(http.MethodGet, path, handler)
-}
-
-func (s *HttpServer) POST(path string, handler http.HandlerFunc) {
-	s.router.Handler(http.MethodPost, path, handler)
-}
-
-func (s *HttpServer) SetNotFoundHandler(handler http.HandlerFunc) {
-	s.router.NotFound = handler
-}
-
-// GetURLParam wrapper around underlying router for getting URL parameters.
-func GetURLParam(r *http.Request, param string) string {
-	return httprouter.ParamsFromContext(r.Context()).ByName(param)
-}
-
-func (s *HttpServer) Start(network, address string) error {
-	listener, err := net.Listen(network, address)
-	if err != nil {
-		return err
-	}
-
-	if listener.Addr().Network() == "unix" {
-		os.Chmod(address, 0777)
-	}
-
-	go func() {
-		if err = s.server.Serve(listener); err != nil && err != http.ErrServerClosed {
-			log.Fatalln(err)
-		}
-	}()
-
-	return nil
-}
-
-func (s *HttpServer) Stop() error {
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-
-	if err := s.server.Shutdown(ctx); err != nil {
-		return err
-	}
-
-	return nil
-}