Add a demonstration program0.4.7

11 files changed, 477 insertions, 110 deletions

diff --git a/bootstrap b/bootstrap
index 7beb367..07f8c35 100755
--- a/bootstrap
+++ b/bootstrap
@@ -12,7 +12,7 @@ mkdir -p .native || exit 1
 cd .native || exit 1
 bash ../configure SHELL=$(which sh) || exit 1
 
-for file in ../src/webid-oidc-issuer ../src/webid-oidc-reverse-proxy ../src/webid-oidc-client-service
+for file in ../src/webid-oidc-issuer ../src/webid-oidc-reverse-proxy ../src/webid-oidc-client-service ../src/webid-oidc-example-app
 do
     sed -i "s|/usr/local/bin/guile|$(which guile)|g" $file || exit 1
 done
diff --git a/doc/manual.html b/doc/manual.html
index 610bc02..20a6bc0 100644
--- a/doc/manual.html
+++ b/doc/manual.html
@@ -1245,6 +1245,12 @@
       </p>
     </info:deffn>
     <p>
+      An example application is provided as the
+      <pre>webid-oidc-example-app</pre> program. It demonstrates how
+      authentication is done. It should help you understand how
+      webid-oidc works.
+    </p>
+    <p>
       The identity provider needs to call the application on the
       web. So, your client should have a public endpoint on the web.
     </p>
diff --git a/guix/vkraus/packages/webid-oidc.scm b/guix/vkraus/packages/webid-oidc.scm
index 372892e..e6d43a1 100644
--- a/guix/vkraus/packages/webid-oidc.scm
+++ b/guix/vkraus/packages/webid-oidc.scm
@@ -67,7 +67,7 @@
                 (format #f "~a/bin/webid-oidc-~a" out program)
                 `("GUILE_LOAD_PATH" ":" = ,mod-paths)
                 `("GUILE_LOAD_COMPILED_PATH" ":" = ,go-paths)))
-             '(issuer reverse-proxy hello client-service))))))))
+             '(issuer reverse-proxy hello client-service example-app))))))))
    (native-inputs
     `(("pkg-config" ,pkg-config)
       ("guile" ,guile-3.0)
diff --git a/man/Makefile.am b/man/Makefile.am
index 5a80f50..54e5e15 100644
--- a/man/Makefile.am
+++ b/man/Makefile.am
@@ -13,3 +13,7 @@ webid-oidc-reverse-proxy.man: ../src/scm/webid-oidc/reverse-proxy.scm ../configu
 webid-oidc-client-service.man: ../src/scm/webid-oidc/client.scm ../configure.ac
 	$(AM_V_GEN) ../pre-inst-env ./reset-env $(HELP2MAN) $(srcdir)/../src/webid-oidc-client-service > $@-t
 	mv $@-t $(srcdir)/$@
+
+webid-oidc-example-app.man: ../src/scm/webid-oidc/example-app.scm ../configure.ac
+	$(AM_V_GEN) ../pre-inst-env ./reset-env $(HELP2MAN) $(srcdir)/../src/webid-oidc-example-app > $@-t
+	mv $@-t $(srcdir)/$@
diff --git a/po/POTFILES.in b/po/POTFILES.in
index dffc889..1dd9e41 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -13,3 +13,4 @@ src/scm/webid-oidc/resource-server.scm
 src/scm/webid-oidc/reverse-proxy.scm
 src/scm/webid-oidc/hello-world.scm
 src/scm/webid-oidc/client.scm
+src/scm/webid-oidc/example-app.scm
diff --git a/po/fr.po b/po/fr.po
index b0938f9..4a1054e 100644
--- a/po/fr.po
+++ b/po/fr.po
@@ -3,7 +3,7 @@ msgstr ""
 "Project-Id-Version: webid-oidc 0.0.0\n"
 "Report-Msgid-Bugs-To: vivien@planete-kraus.eu\n"
 "POT-Creation-Date: 2021-05-10 23:11+0200\n"
-"PO-Revision-Date: 2021-05-10 14:31+0200\n"
+"PO-Revision-Date: 2021-05-10 23:12+0200\n"
 "Last-Translator: Vivien Kraus <vivien@planete-kraus.eu>\n"
 "Language-Team: French <vivien@planete-kraus.eu>\n"
 "Language: fr\n"
@@ -741,11 +741,13 @@ msgstr "Attention : génération d'une nouvelle paire de clé."
 #: src/scm/webid-oidc/identity-provider.scm:147
 #: src/scm/webid-oidc/reverse-proxy.scm:124
 #: src/scm/webid-oidc/hello-world.scm:32 src/scm/webid-oidc/client.scm:606
+#: src/scm/webid-oidc/example-app.scm:101
 msgid "command-line|version"
 msgstr "version"
 
 #: src/scm/webid-oidc/identity-provider.scm:149
 #: src/scm/webid-oidc/hello-world.scm:34 src/scm/webid-oidc/client.scm:608
+#: src/scm/webid-oidc/example-app.scm:103
 msgid "comand-line|help"
 msgstr "aide"
 
@@ -941,6 +943,7 @@ msgstr ""
 #: src/scm/webid-oidc/identity-provider.scm:262
 #: src/scm/webid-oidc/reverse-proxy.scm:207
 #: src/scm/webid-oidc/hello-world.scm:60 src/scm/webid-oidc/client.scm:684
+#: src/scm/webid-oidc/example-app.scm:143
 #, scheme-format
 msgid "~a version ~a\n"
 msgstr "~a version ~a\n"
@@ -1428,129 +1431,152 @@ msgstr "Vous devez définir l'URI de redirection.\n"
 msgid "The client URI should be an URI.\n"
 msgstr "L’URI du client doit être un URI.\n"
 
+#: src/scm/webid-oidc/example-app.scm:36
 #, scheme-format
-#~ msgid "~a.\t~a, certified by ~a;\n"
-#~ msgstr "~a.\t~a, certifié par ~a ;\n"
+msgid "~a.\t~a, certified by ~a;\n"
+msgstr "~a.\t~a, certifié par ~a ;\n"
 
+#: src/scm/webid-oidc/example-app.scm:47
 #, scheme-format
-#~ msgid "~a – ~a\n"
-#~ msgstr "~a – ~a\n"
+msgid "~a – ~a\n"
+msgstr "~a – ~a\n"
 
+#: src/scm/webid-oidc/example-app.scm:66
 #, scheme-format
-#~ msgid "I’m expecting a number between ~a and ~a.\n"
-#~ msgstr "J’attends un nombre entre ~a et ~a.\n"
+msgid "I’m expecting a number between ~a and ~a.\n"
+msgstr "J’attends un nombre entre ~a et ~a.\n"
 
+#: src/scm/webid-oidc/example-app.scm:73
+msgid "Please enter an URI to GET: "
+msgstr "Veuillez entrer un URI à requêter avec GET :"
+
+#: src/scm/webid-oidc/example-app.scm:92
 #, scheme-format
-#~ msgid ""
-#~ "Usage: ~a [OPTIONS]...\n"
-#~ "\n"
-#~ "Demonstrate a webid-oidc application.\n"
-#~ "\n"
-#~ "Options:\n"
-#~ "  -h, --help:\n"
-#~ "      display this help message and exit.\n"
-#~ "  -v, --version:\n"
-#~ "      display the version information (~a) and exit.\n"
-#~ "\n"
-#~ "Environment variables:\n"
-#~ "\n"
-#~ "  LANG: set the locale. Currently ~a.\n"
-#~ "\n"
-#~ "  XDG_CACHE_HOME: where the seed for the key generator is\n"
-#~ "stored. Currently ~a.\n"
-#~ "\n"
-#~ "  XDG_DATA_HOME: where the login credentials are stored. Currently ~a.\n"
-#~ "\n"
-#~ "  HOME: to compute a default value for XDG_CACHE_HOME and\n"
-#~ "XDG_DATA_HOME, if missing. Currently ~a.\n"
-#~ "\n"
-#~ "If you find a bug, send a report to ~a.\n"
-#~ msgstr ""
-#~ "Utilisation : ~a [OPTIONS]...\n"
-#~ "\n"
-#~ "Fait démonstration d’une application webid-oidc.\n"
-#~ "\n"
-#~ "Options :\n"
-#~ "  -h, --aide :\n"
-#~ "      affiche ce message d’aide et quitte.\n"
-#~ "  -v, --version :\n"
-#~ "      affiche le numéro de version (~a) et quitte.\n"
-#~ "\n"
-#~ "Variables d’environnement :\n"
-#~ "\n"
-#~ "  LANG : définit la locale. Actuellement ~a.\n"
-#~ "\n"
-#~ "  XDG_CACHE_HOME : où stocker la graine aléatoire du générateur de\n"
-#~ "clé. Actuellement ~a.\n"
-#~ "\n"
-#~ "  XDG_DATA_HOME : où les données d’authentification sont\n"
-#~ "stockées. Actuellement ~a.\n"
-#~ "\n"
-#~ "  HOME : pour calculer une valeur par défaut de XDG_CACHE_HOME et\n"
-#~ "XDG_DATA_HOME, si manquant. Actuellement ~a.\n"
-#~ "\n"
-#~ "Si vous trouvez une erreur dans le programme, envoyez-en un rapport à\n"
-#~ "~a.\n"
+msgid "Sending a request: ~s\n"
+msgstr "Envoi d’une requête : ~s\n"
+
+#: src/scm/webid-oidc/example-app.scm:111
+#, scheme-format
+msgid ""
+"Usage: ~a [OPTIONS]...\n"
+"\n"
+"Demonstrate a webid-oidc application.\n"
+"\n"
+"Options:\n"
+"  -h, --help:\n"
+"      display this help message and exit.\n"
+"  -v, --version:\n"
+"      display the version information (~a) and exit.\n"
+"\n"
+"Environment variables:\n"
+"\n"
+"  LANG: set the locale. Currently ~a.\n"
+"\n"
+"  XDG_CACHE_HOME: where the seed for the key generator is\n"
+"stored. Currently ~a.\n"
+"\n"
+"  XDG_DATA_HOME: where the login credentials are stored. Currently ~a.\n"
+"\n"
+"  HOME: to compute a default value for XDG_CACHE_HOME and\n"
+"XDG_DATA_HOME, if missing. Currently ~a.\n"
+"\n"
+"If you find a bug, send a report to ~a.\n"
+msgstr ""
+"Utilisation : ~a [OPTIONS]...\n"
+"\n"
+"Fait démonstration d’une application webid-oidc.\n"
+"\n"
+"Options :\n"
+"  -h, --aide :\n"
+"      affiche ce message d’aide et quitte.\n"
+"  -v, --version :\n"
+"      affiche le numéro de version (~a) et quitte.\n"
+"\n"
+"Variables d’environnement :\n"
+"\n"
+"  LANG : définit la locale. Actuellement ~a.\n"
+"\n"
+"  XDG_CACHE_HOME : où stocker la graine aléatoire du générateur de\n"
+"clé. Actuellement ~a.\n"
+"\n"
+"  XDG_DATA_HOME : où les données d’authentification sont\n"
+"stockées. Actuellement ~a.\n"
+"\n"
+"  HOME : pour calculer une valeur par défaut de XDG_CACHE_HOME et\n"
+"XDG_DATA_HOME, si manquant. Actuellement ~a.\n"
+"\n"
+"Si vous trouvez une erreur dans le programme, envoyez-en un rapport à\n"
+"~a.\n"
 
-#~ msgid "First, let’s log in. Here are your options:\n"
-#~ msgstr "En premier lieu, authentifions-nous. Voici vos options :\n"
+#: src/scm/webid-oidc/example-app.scm:147
+msgid "First, let’s log in. Here are your options:\n"
+msgstr "En premier lieu, authentifions-nous. Voici vos options :\n"
 
-#~ msgid "0.\tLog in with a different identity.\n"
-#~ msgstr "0.\tS’authentifier avec une identité différente.\n"
+#: src/scm/webid-oidc/example-app.scm:149
+msgid "0.\tLog in with a different identity.\n"
+msgstr "0.\tS’authentifier avec une identité différente.\n"
 
-#~ msgid "Please indicate your choice number: "
-#~ msgstr "Veuillez indiquer votre choix de numéro : "
+#: src/scm/webid-oidc/example-app.scm:154
+#: src/scm/webid-oidc/example-app.scm:173
+msgid "Please indicate your choice number: "
+msgstr "Veuillez indiquer votre choix de numéro : "
 
-#~ msgid "Please enter your webid, or identity server: "
-#~ msgstr "Veuillez entrer votre webid, ou serveur d’identité : "
+#: src/scm/webid-oidc/example-app.scm:159
+msgid "Please enter your webid, or identity server: "
+msgstr "Veuillez entrer votre webid, ou serveur d’identité : "
 
-#~ msgid "There are different possible identity providers for your webid:\n"
-#~ msgstr ""
-#~ "Il y a différents fournisseurs d’identité possibles pour votre\n"
-#~ "webid :\n"
+#: src/scm/webid-oidc/example-app.scm:169
+msgid "There are different possible identity providers for your webid:\n"
+msgstr ""
+"Il y a différents fournisseurs d’identité possibles pour votre\n"
+"webid :\n"
 
+#: src/scm/webid-oidc/example-app.scm:176
 #, scheme-format
-#~ msgid ""
-#~ "Please visit the following URI with a web browser:\n"
-#~ "~a\n"
-#~ msgstr ""
-#~ "Veuillez accéder à cet URI avec un navigateur web :\n"
-#~ "~a\n"
+msgid ""
+"Please visit the following URI with a web browser:\n"
+"~a\n"
+msgstr ""
+"Veuillez accéder à cet URI avec un navigateur web :\n"
+"~a\n"
 
-#~ msgid "Please paste your authorization code: "
-#~ msgstr "Veuillez coller votre code d’autorisation : "
+#: src/scm/webid-oidc/example-app.scm:178
+msgid "Please paste your authorization code: "
+msgstr "Veuillez coller votre code d’autorisation : "
 
+#: src/scm/webid-oidc/example-app.scm:188
 #, scheme-format
-#~ msgid ""
-#~ "Log in success. Keep this identity token for yourself:\n"
-#~ "\n"
-#~ "~a\n"
-#~ "\n"
-#~ "Now, you can do authenticated request by presenting the following access "
-#~ "token:\n"
-#~ "\n"
-#~ "~a\n"
-#~ "\n"
-#~ "and signing DPoP proofs with the following key:\n"
-#~ "\n"
-#~ "~a\n"
-#~ msgstr ""
-#~ "Authentification réussie. Gardez ce jeton d’identité pour vous :\n"
-#~ "\n"
-#~ "~a\n"
-#~ "\n"
-#~ "À partir de maintenant, vous pouvez effectuer des requêtes\n"
-#~ "authentifiées en présentant le jeton d’accès suivant :\n"
-#~ "\n"
-#~ "~a\n"
-#~ "\n"
-#~ "et en signant les preuves DPoP avec la clé suivante :\n"
-#~ "\n"
-#~ "~a\n"
+msgid ""
+"Log in success. Keep this identity token for yourself:\n"
+"\n"
+"~a\n"
+"\n"
+"Now, you can do authenticated request by presenting the following access "
+"token:\n"
+"\n"
+"~a\n"
+"\n"
+"and signing DPoP proofs with the following key:\n"
+"\n"
+"~a\n"
+msgstr ""
+"Authentification réussie. Gardez ce jeton d’identité pour vous :\n"
+"\n"
+"~a\n"
+"\n"
+"À partir de maintenant, vous pouvez effectuer des requêtes\n"
+"authentifiées en présentant le jeton d’accès suivant :\n"
+"\n"
+"~a\n"
+"\n"
+"et en signant les preuves DPoP avec la clé suivante :\n"
+"\n"
+"~a\n"
 
+#: src/scm/webid-oidc/example-app.scm:209
 #, scheme-format
-#~ msgid "There was an error: ~a\n"
-#~ msgstr "Il y a eu une erreur : ~a\n"
+msgid "There was an error: ~a\n"
+msgstr "Il y a eu une erreur : ~a\n"
 
 #, scheme-format
 #~ msgid ""
diff --git a/po/webid-oidc.pot b/po/webid-oidc.pot
index 63927e0..b974da8 100644
--- a/po/webid-oidc.pot
+++ b/po/webid-oidc.pot
@@ -722,11 +722,13 @@ msgstr ""
 #: src/scm/webid-oidc/identity-provider.scm:147
 #: src/scm/webid-oidc/reverse-proxy.scm:124
 #: src/scm/webid-oidc/hello-world.scm:32 src/scm/webid-oidc/client.scm:606
+#: src/scm/webid-oidc/example-app.scm:101
 msgid "command-line|version"
 msgstr ""
 
 #: src/scm/webid-oidc/identity-provider.scm:149
 #: src/scm/webid-oidc/hello-world.scm:34 src/scm/webid-oidc/client.scm:608
+#: src/scm/webid-oidc/example-app.scm:103
 msgid "comand-line|help"
 msgstr ""
 
@@ -849,6 +851,7 @@ msgstr ""
 #: src/scm/webid-oidc/identity-provider.scm:262
 #: src/scm/webid-oidc/reverse-proxy.scm:207
 #: src/scm/webid-oidc/hello-world.scm:60 src/scm/webid-oidc/client.scm:684
+#: src/scm/webid-oidc/example-app.scm:143
 #, scheme-format
 msgid "~a version ~a\n"
 msgstr ""
@@ -1214,3 +1217,109 @@ msgstr ""
 #: src/scm/webid-oidc/client.scm:715
 msgid "The client URI should be an URI.\n"
 msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:36
+#, scheme-format
+msgid "~a.\t~a, certified by ~a;\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:47
+#, scheme-format
+msgid "~a – ~a\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:66
+#, scheme-format
+msgid "I’m expecting a number between ~a and ~a.\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:73
+msgid "Please enter an URI to GET: "
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:92
+#, scheme-format
+msgid "Sending a request: ~s\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:111
+#, scheme-format
+msgid ""
+"Usage: ~a [OPTIONS]...\n"
+"\n"
+"Demonstrate a webid-oidc application.\n"
+"\n"
+"Options:\n"
+"  -h, --help:\n"
+"      display this help message and exit.\n"
+"  -v, --version:\n"
+"      display the version information (~a) and exit.\n"
+"\n"
+"Environment variables:\n"
+"\n"
+"  LANG: set the locale. Currently ~a.\n"
+"\n"
+"  XDG_CACHE_HOME: where the seed for the key generator is\n"
+"stored. Currently ~a.\n"
+"\n"
+"  XDG_DATA_HOME: where the login credentials are stored. Currently ~a.\n"
+"\n"
+"  HOME: to compute a default value for XDG_CACHE_HOME and\n"
+"XDG_DATA_HOME, if missing. Currently ~a.\n"
+"\n"
+"If you find a bug, send a report to ~a.\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:147
+msgid "First, let’s log in. Here are your options:\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:149
+msgid "0.\tLog in with a different identity.\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:154
+#: src/scm/webid-oidc/example-app.scm:173
+msgid "Please indicate your choice number: "
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:159
+msgid "Please enter your webid, or identity server: "
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:169
+msgid "There are different possible identity providers for your webid:\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:176
+#, scheme-format
+msgid ""
+"Please visit the following URI with a web browser:\n"
+"~a\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:178
+msgid "Please paste your authorization code: "
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:188
+#, scheme-format
+msgid ""
+"Log in success. Keep this identity token for yourself:\n"
+"\n"
+"~a\n"
+"\n"
+"Now, you can do authenticated request by presenting the following access "
+"token:\n"
+"\n"
+"~a\n"
+"\n"
+"and signing DPoP proofs with the following key:\n"
+"\n"
+"~a\n"
+msgstr ""
+
+#: src/scm/webid-oidc/example-app.scm:209
+#, scheme-format
+msgid "There was an error: ~a\n"
+msgstr ""
diff --git a/src/Makefile.am b/src/Makefile.am
index 527f201..3dd6822 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,6 +1,6 @@
 lib_LTLIBRARIES += %reldir%/libwebidoidc.la
 
-dist_bin_SCRIPTS += %reldir%/webid-oidc-issuer %reldir%/webid-oidc-reverse-proxy %reldir%/webid-oidc-hello %reldir%/webid-oidc-client-service
+dist_bin_SCRIPTS += %reldir%/webid-oidc-issuer %reldir%/webid-oidc-reverse-proxy %reldir%/webid-oidc-hello %reldir%/webid-oidc-client-service %reldir%/webid-oidc-example-app
 
 AM_CPPFLAGS += -I %reldir% -I $(srcdir)/%reldir%
 
diff --git a/src/scm/webid-oidc/Makefile.am b/src/scm/webid-oidc/Makefile.am
index 1f9cb5d..6aeadfc 100644
--- a/src/scm/webid-oidc/Makefile.am
+++ b/src/scm/webid-oidc/Makefile.am
@@ -23,7 +23,8 @@ dist_webidoidcmod_DATA += \
   %reldir%/resource-server.scm \
   %reldir%/hello-world.scm \
   %reldir%/reverse-proxy.scm \
-  %reldir%/client.scm
+  %reldir%/client.scm \
+  %reldir%/example-app.scm
 
 webidoidcgo_DATA += \
   %reldir%/errors.go \
@@ -50,6 +51,7 @@ webidoidcgo_DATA += \
   %reldir%/resource-server.go \
   %reldir%/hello-world.go \
   %reldir%/reverse-proxy.go \
-  %reldir%/client.go
+  %reldir%/client.go \
+  %reldir%/example-app.go
 
 EXTRA_DIST += %reldir%/ChangeLog
diff --git a/src/scm/webid-oidc/example-app.scm b/src/scm/webid-oidc/example-app.scm
new file mode 100644
index 0000000..ec92fb9
--- /dev/null
+++ b/src/scm/webid-oidc/example-app.scm
@@ -0,0 +1,212 @@
+(define-module (webid-oidc example-app)
+  #:use-module (webid-oidc client)
+  #:use-module (webid-oidc errors)
+  #:use-module ((webid-oidc cache) #:prefix cache:)
+  #:use-module (webid-oidc dpop-proof)
+  #:use-module ((webid-oidc stubs) #:prefix stubs:)
+  #:use-module ((webid-oidc refresh-token) #:prefix refresh:)
+  #:use-module ((webid-oidc config) #:prefix cfg:)
+  #:use-module (web uri)
+  #:use-module (web client)
+  #:use-module (web response)
+  #:use-module (web server)
+  #:use-module (ice-9 optargs)
+  #:use-module (ice-9 receive)
+  #:use-module (srfi srfi-19)
+  #:use-module (ice-9 i18n)
+  #:use-module (ice-9 getopt-long)
+  #:use-module (ice-9 suspendable-ports)
+  #:use-module (ice-9 textual-ports)
+  #:use-module (ice-9 rdelim)
+  #:use-module (sxml simple)
+  #:use-module (rnrs bytevectors))
+
+(define (G_ text)
+  (let ((out (gettext text)))
+    (if (string=? out text)
+        ;; No translation, disambiguate
+        (car (reverse (string-split text #\|)))
+        out)))
+
+(define (enumerate-profiles profiles)
+  (define (aux i)
+    (when (< i (vector-length profiles))
+      (let ((prof (vector-ref profiles i)))
+        (format #t (G_ "~a.\t~a, certified by ~a;\n")
+                (+ i 1)
+                (uri->string (car prof))
+                (uri->string (cadr prof))))
+      (aux (+ i 1))))
+  (aux 0))
+
+(define (enumerate-providers providers)
+  (define (aux i)
+    (when (< i (vector-length providers))
+      (let ((prov (vector-ref providers i)))
+        (format #t (G_ "~a – ~a\n")
+                (+ i 1)
+                (prov)))
+      (aux (+ i 1))))
+  (aux 0))
+
+(define (select-choice mini maxi question)
+  (format #t "~a" question)
+  (let* ((line
+          (read-line (current-input-port) 'trim))
+         (number (false-if-exception (string->number line))))
+    (cond
+     ((eof-object? line)
+      (exit 0))
+     ((and (integer? number)
+           (>= number mini)
+           (<= number maxi))
+      number)
+     (else
+      (format #t (G_ "I’m expecting a number between ~a and ~a.\n")
+              mini maxi)
+      (select-choice mini maxi question)))))
+
+(define cache-http-get (cache:with-cache))
+
+(define (inner-main-loop http-request)
+  (format #t (G_ "Please enter an URI to GET: "))
+  (let ((line (read-line (current-input-port) 'trim)))
+    (unless (eof-object? line)
+      (let ((uri (string->uri line)))
+        (receive (response response-body)
+            (http-request uri)
+          (let ((write-body
+                 (write-response response (current-output-port))))
+            (when (string? response-body)
+              (set! response-body (string->utf8 response-body)))
+            (when response-body
+              (write-response-body write-body response-body)))))
+      (inner-main-loop http-request))))
+
+(define (main-loop id-token access-token key)
+  (let ((my-http-request
+         (make-client id-token access-token key
+                      #:http-request
+                      (lambda args
+                        (format (current-error-port) (G_ "Sending a request: ~s\n") args)
+                        (apply http-request args)))))
+    (inner-main-loop my-http-request)))
+
+(define-public (inner-main)
+  (setlocale LC_ALL "")
+  (bindtextdomain cfg:package cfg:localedir)
+  (textdomain cfg:package)
+  (let ((version-sym
+         (string->symbol (G_ "command-line|version")))
+        (help-sym
+         (string->symbol (G_ "comand-line|help"))))
+    (let ((options
+           (let ((option-spec
+                  `((,version-sym (single-char #\v) (value #f))
+                    (,help-sym (single-char #\h) (value #f)))))
+             (getopt-long (command-line) option-spec))))
+      (cond
+       ((option-ref options help-sym #f)
+        (format #t (G_ "Usage: ~a [OPTIONS]...
+
+Demonstrate a webid-oidc application.
+
+Options:
+  -h, --help:
+      display this help message and exit.
+  -v, --version:
+      display the version information (~a) and exit.
+
+Environment variables:
+
+  LANG: set the locale. Currently ~a.
+
+  XDG_CACHE_HOME: where the seed for the key generator is
+stored. Currently ~a.
+
+  XDG_DATA_HOME: where the login credentials are stored. Currently ~a.
+
+  HOME: to compute a default value for XDG_CACHE_HOME and
+XDG_DATA_HOME, if missing. Currently ~a.
+
+If you find a bug, send a report to ~a.
+")
+                (car (command-line))
+                cfg:version
+                (or (getenv "LANG") "")
+                (or (getenv "XDG_CACHE_HOME") "")
+                (or (getenv "XDG_DATA_HOME") "")
+                (or (getenv "HOME") "")
+                cfg:package-bugreport))
+       ((option-ref options version-sym #f)
+        (format #t (G_ "~a version ~a\n")
+                cfg:package cfg:version))
+       (else
+        (let ((profiles (list->vector (list-profiles))))
+          (format #t (G_ "First, let’s log in. Here are your options:\n"))
+          (enumerate-profiles profiles)
+          (format #t (G_ "0.\tLog in with a different identity.\n"))
+          (let ((i-profile
+                 (select-choice
+                  0
+                  (vector-length profiles)
+                  (G_ "Please indicate your choice number: "))))
+            (receive (id-token access-token key)
+                (if (eqv? i-profile 0)
+                    (setup
+                     (lambda ()
+                       (format #t (G_ "Please enter your webid, or identity server: "))
+                       (read-line (current-input-port) 'trim))
+                     (lambda (providers)
+                       (cond
+                        ((null? providers)
+                         (error "No, this cannot happen."))
+                        ((null? (cdr providers))
+                         (car providers))
+                        (else
+                         (set! providers (list->vector providers))
+                         (format #t (G_ "There are different possible identity providers for your webid:\n"))
+                         (enumerate-providers providers)
+                         (let ((i-provider
+                                (select-choice 1 (- (vector-length providers) 1)
+                                               (G_ "Please indicate your choice number: "))))
+                           (vector-ref providers i-provider)))))
+                     (lambda (uri)
+                       (format #t (G_ "Please visit the following URI with a web browser:\n~a\n")
+                               (uri->string uri))
+                       (format #t (G_ "Please paste your authorization code: "))
+                       (read-line (current-input-port) 'trim))
+                     #:client-id "https://webid-oidc-demo.planete-kraus.eu/example-application#id"
+                     #:redirect-uri "https://webid-oidc-demo.planete-kraus.eu/authorized"
+                     #:http-get cache-http-get)
+                    (let ((profile (vector-ref profiles (- i-profile 1))))
+                      (let ((webid (car profile))
+                            (issuer (cadr profile))
+                            (refresh-token (caddr profile)))
+                        (login webid issuer refresh-token #:http-get cache-http-get))))
+              (format #t (G_ "Log in success. Keep this identity token for yourself:
+
+~a
+
+Now, you can do authenticated request by presenting the following access token:
+
+~a
+
+and signing DPoP proofs with the following key:
+
+~a
+")
+                      (stubs:scm->json-string id-token #:pretty #t)
+                      access-token
+                      (stubs:scm->json-string key #:pretty #t))
+              (main-loop id-token access-token key)))))))))
+
+(define-public (main)
+  (with-exception-handler
+      (lambda (error)
+        (format (current-error-port)
+                (G_ "There was an error: ~a\n")
+                (error->str error)))
+    (lambda ()
+      (inner-main))
+    #:unwind? #t))
diff --git a/src/webid-oidc-example-app b/src/webid-oidc-example-app
new file mode 100755
index 0000000..ebf2da8
--- /dev/null
+++ b/src/webid-oidc-example-app
@@ -0,0 +1,7 @@
+#!/usr/local/bin/guile \
+--no-auto-compile -s
+!#
+
+(use-modules (webid-oidc example-app))
+
+(main)