38 files changed, 1333 insertions, 27 deletions

diff --git a/.dockerignore b/.dockerignore
index a0d28dc6..96fd31c5 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -4,6 +4,9 @@
 .github
 tests
 
+# Docker Compose resources
+docker-compose.yml
+
 # Shaarli runtime resources
 cache/*
 data/*
diff --git a/.gitattributes b/.gitattributes
index 9d22f11b..9a92bc37 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -35,6 +35,7 @@ doc/**/*.json     export-ignore
 doc/**/*.md       export-ignore
 .docker/          export-ignore
 .dockerignore     export-ignore
+docker-compose.*  export-ignore
 Dockerfile*       export-ignore
 Doxyfile          export-ignore
 Makefile          export-ignore
diff --git a/.htaccess b/.htaccess
index 7ba4744b..b238854c 100644
--- a/.htaccess
+++ b/.htaccess
@@ -14,3 +14,10 @@ RewriteRule .* - [e=HTTP_AUTHORIZATION:%1]
 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
 RewriteRule ^ index.php [QSA,L]
+
+<Limit GET POST PUT DELETE OPTIONS>
+    Require all granted
+</Limit>
+<LimitExcept GET POST PUT DELETE OPTIONS>
+    Require all denied
+</LimitExcept>
diff --git a/Dockerfile b/Dockerfile
index 6261e81b..d8921cee 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -25,7 +25,7 @@ RUN cd shaarli \
 
 # Stage 4:
 # - Shaarli image
-FROM alpine:3.7
+FROM alpine:3.8
 LABEL maintainer="Shaarli Community"
 
 RUN apk --update --no-cache add \
diff --git a/Dockerfile.armhf b/Dockerfile.armhf
index 5dcc34aa..1185e2df 100644
--- a/Dockerfile.armhf
+++ b/Dockerfile.armhf
@@ -1,9 +1,38 @@
-FROM lsiobase/alpine.armhf:3.6
+# Stage 1:
+# - Copy Shaarli sources
+# - Build documentation
+FROM arm32v6/alpine:3.8 as docs
+ADD . /usr/src/app/shaarli
+RUN apk --update --no-cache add py2-pip \
+    && cd /usr/src/app/shaarli \
+    && pip install --no-cache-dir mkdocs \
+    && mkdocs build --clean
+
+# Stage 2:
+# - Resolve PHP dependencies with Composer
+FROM arm32v6/alpine:3.8 as composer
+COPY --from=docs /usr/src/app/shaarli /app/shaarli
+RUN apk --update --no-cache add php7-mbstring composer \
+    && cd /app/shaarli \
+    && composer --prefer-dist --no-dev install
+
+# Stage 3:
+# - Frontend dependencies
+FROM arm32v6/alpine:3.8 as node
+COPY --from=composer /app/shaarli /shaarli
+RUN apk --update --no-cache add yarn nodejs-current python2 build-base \
+    && cd /shaarli \
+    && yarn install \
+    && yarn run build \
+    && rm -rf node_modules
+
+# Stage 4:
+# - Shaarli image
+FROM arm32v6/alpine:3.8
 LABEL maintainer="Shaarli Community"
 
 RUN apk --update --no-cache add \
         ca-certificates \
-        curl \
         nginx \
         php7 \
         php7-ctype \
@@ -15,7 +44,6 @@ RUN apk --update --no-cache add \
         php7-json \
         php7-mbstring \
         php7-openssl \
-        php7-phar \
         php7-session \
         php7-xml \
         php7-zlib \
@@ -25,22 +53,19 @@ COPY .docker/nginx.conf /etc/nginx/nginx.conf
 COPY .docker/php-fpm.conf /etc/php7/php-fpm.conf
 COPY .docker/services.d /etc/services.d
 
-RUN curl -sS https://getcomposer.org/installer | php7 -- --install-dir=/usr/local/bin --filename=composer \
-    && rm -rf /etc/php7/php-fpm.d/www.conf \
+RUN rm -rf /etc/php7/php-fpm.d/www.conf \
     && sed -i 's/post_max_size.*/post_max_size = 10M/' /etc/php7/php.ini \
     && sed -i 's/upload_max_filesize.*/upload_max_filesize = 10M/' /etc/php7/php.ini
 
 
 WORKDIR /var/www
-RUN curl -L https://github.com/shaarli/Shaarli/archive/master.tar.gz | tar xzf - \
-    && mv Shaarli-master shaarli \
-    && cd shaarli \
-    && composer --prefer-dist --no-dev install \
-    && rm -rf ~/.composer \
-    && chown -R nginx:nginx . \
+COPY --from=node /shaarli /var/www/shaarli
+
+RUN chown -R nginx:nginx . \
     && ln -sf /dev/stdout /var/log/nginx/shaarli.access.log \
     && ln -sf /dev/stderr /var/log/nginx/shaarli.error.log
 
+VOLUME /var/www/shaarli/cache
 VOLUME /var/www/shaarli/data
 
 EXPOSE 80
diff --git a/application/api/ApiUtils.php b/application/api/ApiUtils.php
index f154bb52..fc5ecaf1 100644
--- a/application/api/ApiUtils.php
+++ b/application/api/ApiUtils.php
@@ -134,4 +134,20 @@ class ApiUtils
 
         return $oldLink;
     }
+
+    /**
+     * Format a Tag for the REST API.
+     *
+     * @param string $tag         Tag name
+     * @param int    $occurrences Number of links using this tag
+     *
+     * @return array Link data formatted for the REST API.
+     */
+    public static function formatTag($tag, $occurences)
+    {
+        return [
+            'name'       => $tag,
+            'occurrences' => $occurences,
+        ];
+    }
 }
diff --git a/application/api/controllers/Links.php b/application/api/controllers/Links.php
index 3a9c0355..ffcfd4c7 100644
--- a/application/api/controllers/Links.php
+++ b/application/api/controllers/Links.php
@@ -68,16 +68,16 @@ class Links extends ApiController
         }
 
         // 'environment' is set by Slim and encapsulate $_SERVER.
-        $index = index_url($this->ci['environment']);
+        $indexUrl = index_url($this->ci['environment']);
 
         $out = [];
-        $cpt = 0;
+        $index = 0;
         foreach ($links as $link) {
             if (count($out) >= $limit) {
                 break;
             }
-            if ($cpt++ >= $offset) {
-                $out[] = ApiUtils::formatLink($link, $index);
+            if ($index++ >= $offset) {
+                $out[] = ApiUtils::formatLink($link, $indexUrl);
             }
         }
 
diff --git a/application/api/controllers/Tags.php b/application/api/controllers/Tags.php
new file mode 100644
index 00000000..6dd78750
--- /dev/null
+++ b/application/api/controllers/Tags.php
@@ -0,0 +1,161 @@
+<?php
+
+namespace Shaarli\Api\Controllers;
+
+use Shaarli\Api\ApiUtils;
+use Shaarli\Api\Exceptions\ApiBadParametersException;
+use Shaarli\Api\Exceptions\ApiLinkNotFoundException;
+use Shaarli\Api\Exceptions\ApiTagNotFoundException;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+/**
+ * Class Tags
+ *
+ * REST API Controller: all services related to tags collection.
+ *
+ * @package Api\Controllers
+ */
+class Tags extends ApiController
+{
+    /**
+     * @var int Number of links returned if no limit is provided.
+     */
+    public static $DEFAULT_LIMIT = 'all';
+
+    /**
+     * Retrieve a list of tags, allowing different filters.
+     *
+     * @param Request  $request  Slim request.
+     * @param Response $response Slim response.
+     *
+     * @return Response response.
+     *
+     * @throws ApiBadParametersException Invalid parameters.
+     */
+    public function getTags($request, $response)
+    {
+        $visibility = $request->getParam('visibility');
+        $tags = $this->linkDb->linksCountPerTag([], $visibility);
+
+        // Return tags from the {offset}th tag, starting from 0.
+        $offset = $request->getParam('offset');
+        if (! empty($offset) && ! ctype_digit($offset)) {
+            throw new ApiBadParametersException('Invalid offset');
+        }
+        $offset = ! empty($offset) ? intval($offset) : 0;
+        if ($offset > count($tags)) {
+            return $response->withJson([], 200, $this->jsonStyle);
+        }
+
+        // limit parameter is either a number of links or 'all' for everything.
+        $limit = $request->getParam('limit');
+        if (empty($limit)) {
+            $limit = self::$DEFAULT_LIMIT;
+        }
+        if (ctype_digit($limit)) {
+            $limit = intval($limit);
+        } elseif ($limit === 'all') {
+            $limit = count($tags);
+        } else {
+            throw new ApiBadParametersException('Invalid limit');
+        }
+
+        $out = [];
+        $index = 0;
+        foreach ($tags as $tag => $occurrences) {
+            if (count($out) >= $limit) {
+                break;
+            }
+            if ($index++ >= $offset) {
+                $out[] = ApiUtils::formatTag($tag, $occurrences);
+            }
+        }
+
+        return $response->withJson($out, 200, $this->jsonStyle);
+    }
+
+    /**
+     * Return a single formatted tag by its name.
+     *
+     * @param Request  $request  Slim request.
+     * @param Response $response Slim response.
+     * @param array    $args     Path parameters. including the tag name.
+     *
+     * @return Response containing the link array.
+     *
+     * @throws ApiTagNotFoundException generating a 404 error.
+     */
+    public function getTag($request, $response, $args)
+    {
+        $tags = $this->linkDb->linksCountPerTag();
+        if (!isset($tags[$args['tagName']])) {
+            throw new ApiTagNotFoundException();
+        }
+        $out = ApiUtils::formatTag($args['tagName'], $tags[$args['tagName']]);
+
+        return $response->withJson($out, 200, $this->jsonStyle);
+    }
+
+    /**
+     * Rename a tag from the given name.
+     * If the new name provided matches an existing tag, they will be merged.
+     *
+     * @param Request  $request  Slim request.
+     * @param Response $response Slim response.
+     * @param array    $args     Path parameters. including the tag name.
+     *
+     * @return Response response.
+     *
+     * @throws ApiTagNotFoundException generating a 404 error.
+     * @throws ApiBadParametersException new tag name not provided
+     */
+    public function putTag($request, $response, $args)
+    {
+        $tags = $this->linkDb->linksCountPerTag();
+        if (! isset($tags[$args['tagName']])) {
+            throw new ApiTagNotFoundException();
+        }
+
+        $data = $request->getParsedBody();
+        if (empty($data['name'])) {
+            throw new ApiBadParametersException('New tag name is required in the request body');
+        }
+
+        $updated = $this->linkDb->renameTag($args['tagName'], $data['name']);
+        $this->linkDb->save($this->conf->get('resource.page_cache'));
+        foreach ($updated as $link) {
+            $this->history->updateLink($link);
+        }
+
+        $tags = $this->linkDb->linksCountPerTag();
+        $out = ApiUtils::formatTag($data['name'], $tags[$data['name']]);
+        return $response->withJson($out, 200, $this->jsonStyle);
+    }
+
+    /**
+     * Delete an existing tag by its name.
+     *
+     * @param Request  $request  Slim request.
+     * @param Response $response Slim response.
+     * @param array    $args     Path parameters. including the tag name.
+     *
+     * @return Response response.
+     *
+     * @throws ApiTagNotFoundException generating a 404 error.
+     */
+    public function deleteTag($request, $response, $args)
+    {
+        $tags = $this->linkDb->linksCountPerTag();
+        if (! isset($tags[$args['tagName']])) {
+            throw new ApiTagNotFoundException();
+        }
+        $updated = $this->linkDb->renameTag($args['tagName'], null);
+        $this->linkDb->save($this->conf->get('resource.page_cache'));
+        foreach ($updated as $link) {
+            $this->history->updateLink($link);
+        }
+
+        return $response->withStatus(204);
+    }
+}
diff --git a/application/api/exceptions/ApiTagNotFoundException.php b/application/api/exceptions/ApiTagNotFoundException.php
new file mode 100644
index 00000000..eed5afa5
--- /dev/null
+++ b/application/api/exceptions/ApiTagNotFoundException.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace Shaarli\Api\Exceptions;
+
+
+use Slim\Http\Response;
+
+/**
+ * Class ApiTagNotFoundException
+ *
+ * Tag selected by name couldn't be found in the datastore, results in a 404 error.
+ *
+ * @package Shaarli\Api\Exceptions
+ */
+class ApiTagNotFoundException extends ApiException
+{
+    /**
+     * ApiLinkNotFoundException constructor.
+     */
+    public function __construct()
+    {
+        $this->message = 'Tag not found';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getApiResponse()
+    {
+        return $this->buildApiResponse(404);
+    }
+}
diff --git a/doc/md/REST-API.md b/doc/md/REST-API.md
index c016de56..11bd1cd2 100644
--- a/doc/md/REST-API.md
+++ b/doc/md/REST-API.md
@@ -152,3 +152,22 @@ See the reference API client:
 
 - [Documentation](http://python-shaarli-client.readthedocs.io/en/latest/) on ReadTheDocs
 - [python-shaarli-client](https://github.com/shaarli/python-shaarli-client) on Github
+
+## Troubleshooting
+
+### Debug mode
+
+> This should never be used in a production environment.
+
+For security reasons, authentication issues will always return an `HTTP 401` error code without any detail.
+
+It is possible to enable the debug mode in `config.json.php` 
+to get the actual error message in the HTTP response body with:
+
+```json
+{
+  "dev": {
+    "debug": true
+  }
+}
+```
diff --git a/doc/md/Upgrade-and-migration.md b/doc/md/Upgrade-and-migration.md
index 451ca36d..d5682a34 100644
--- a/doc/md/Upgrade-and-migration.md
+++ b/doc/md/Upgrade-and-migration.md
@@ -27,7 +27,7 @@ As all user data is kept under `data`, this is the only directory you need to wo
 
 - backup the `data` directory
 - install or update Shaarli:
-    - fresh installation - see [Download and installation](Download-and-installation)
+    - fresh installation - see [Download and Installation](Download-and-Installation)
     - update - see the following sections
 - check or restore the `data` directory
 
@@ -35,7 +35,7 @@ As all user data is kept under `data`, this is the only directory you need to wo
 
 All tagged revisions can be downloaded as tarballs or ZIP archives from the [releases](https://github.com/shaarli/Shaarli/releases) page.
 
-We recommend that you use the latest release tarball with the `-full` suffix. It contains the dependencies, please read [Download and installation](Download-and-installation) for `git` complete instructions.
+We recommend that you use the latest release tarball with the `-full` suffix. It contains the dependencies, please read [Download and Installation](Download-and-Installation) for `git` complete instructions.
 
 Once downloaded, extract the archive locally and update your remote installation (e.g. via FTP) -be sure you keep the content of the `data` directory!
 
diff --git a/doc/md/docker/reverse-proxy-configuration.md b/doc/md/docker/reverse-proxy-configuration.md
index 6066140e..e53c9422 100644
--- a/doc/md/docker/reverse-proxy-configuration.md
+++ b/doc/md/docker/reverse-proxy-configuration.md
@@ -13,12 +13,14 @@ This guide assumes that:
     - [mod_proxy](https://httpd.apache.org/docs/2.4/mod/mod_proxy.html)
     - [Reverse Proxy Request Headers](https://httpd.apache.org/docs/2.4/mod/mod_proxy.html#x-headers)
 
-The following HTTP headers are set by using the `ProxyPass` directive:
+The following HTTP headers are set when the `ProxyPass` directive is set:
 
 - `X-Forwarded-For`
 - `X-Forwarded-Host`
 - `X-Forwarded-Server`
 
+The original `SERVER_NAME` can be sent to the proxied host by setting the [`ProxyPreserveHost`](https://httpd.apache.org/docs/2.4/mod/mod_proxy.html#ProxyPreserveHost) directive to `On`.
+
 ```apache
 <VirtualHost *:80>
     ServerName shaarli.domain.tld
@@ -37,7 +39,8 @@ The following HTTP headers are set by using the `ProxyPass` directive:
     CustomLog /var/log/apache2/shaarli-access.log combined
 
     RequestHeader set X-Forwarded-Proto "https"
-
+    ProxyPreserveHost On
+    
     ProxyPass        / http://127.0.0.1:10080/
     ProxyPassReverse / http://127.0.0.1:10080/
 </VirtualHost>
diff --git a/doc/md/Backup,-restore,-import-and-export.md b/doc/md/guides/backup-restore-import-export.md
index bb790074..bb790074 100644
--- a/doc/md/Backup,-restore,-import-and-export.md
+++ b/doc/md/guides/backup-restore-import-export.md
diff --git a/doc/md/guides/images/01-create-droplet-distro.jpg b/doc/md/guides/images/01-create-droplet-distro.jpg
new file mode 100644
index 00000000..63682ba8
--- /dev/null
+++ b/doc/md/guides/images/01-create-droplet-distro.jpg
diff --git a/doc/md/guides/images/02-create-droplet-region.jpg b/doc/md/guides/images/02-create-droplet-region.jpg
new file mode 100644
index 00000000..135a78be
--- /dev/null
+++ b/doc/md/guides/images/02-create-droplet-region.jpg
diff --git a/doc/md/guides/images/03-create-droplet-size.jpg b/doc/md/guides/images/03-create-droplet-size.jpg
new file mode 100644
index 00000000..aa5b2fd2
--- /dev/null
+++ b/doc/md/guides/images/03-create-droplet-size.jpg
diff --git a/doc/md/guides/images/04-finalize.jpg b/doc/md/guides/images/04-finalize.jpg
new file mode 100644
index 00000000..68ec0dc5
--- /dev/null
+++ b/doc/md/guides/images/04-finalize.jpg
diff --git a/doc/md/guides/images/05-droplet.jpg b/doc/md/guides/images/05-droplet.jpg
new file mode 100644
index 00000000..44e93a1e
--- /dev/null
+++ b/doc/md/guides/images/05-droplet.jpg
diff --git a/doc/md/guides/images/06-domain.jpg b/doc/md/guides/images/06-domain.jpg
new file mode 100644
index 00000000..5827dd93
--- /dev/null
+++ b/doc/md/guides/images/06-domain.jpg
diff --git a/doc/md/guides/images/07-installation.jpg b/doc/md/guides/images/07-installation.jpg
new file mode 100644
index 00000000..42cc9f10
--- /dev/null
+++ b/doc/md/guides/images/07-installation.jpg
diff --git a/doc/md/guides/install-shaarli-with-debian9-and-docker.md b/doc/md/guides/install-shaarli-with-debian9-and-docker.md
new file mode 100644
index 00000000..f1b26d47
--- /dev/null
+++ b/doc/md/guides/install-shaarli-with-debian9-and-docker.md
@@ -0,0 +1,257 @@
+_Last updated on 2018-07-01._
+
+## Goals
+- Getting a Virtual Private Server (VPS)
+- Running Shaarli:
+    - as a Docker container,
+    - using the Træfik reverse proxy,
+    - securized with TLS certificates from Let's Encrypt.
+
+
+The following components and tools will be used:
+
+- [Debian](https://www.debian.org/), a GNU/Linux distribution widely used in
+  server environments;
+- [Docker](https://docs.docker.com/engine/docker-overview/), an open platform
+  for developing, shipping, and running applications;
+- [Docker Compose](https://docs.docker.com/compose/), a tool for defining and
+  running multi-container Docker applications.
+
+
+More information can be found in the [Resources](#resources) section at the
+bottom of the guide.
+
+## Getting a Virtual Private Server
+For this guide, I went for the smallest VPS available from DigitalOcean,
+a Droplet with 1 CPU, 1 GiB RAM and 25 GiB SSD storage, which costs
+$5/month ($0.007/hour):
+
+- [Droplets Overview](https://www.digitalocean.com/docs/droplets/overview/)
+- [Pricing](https://www.digitalocean.com/pricing/)
+- [How to Create a Droplet from the DigitalOcean Control Panel](https://www.digitalocean.com/docs/droplets/how-to/create/)
+- [How to Add SSH Keys to Droplets](https://www.digitalocean.com/docs/droplets/how-to/add-ssh-keys/)
+- [Initial Server Setup with Debian 8](https://www.digitalocean.com/community/tutorials/initial-server-setup-with-debian-8) (also applies to Debian 9)
+- [An Introduction to Securing your Linux VPS](https://www.digitalocean.com/community/tutorials/an-introduction-to-securing-your-linux-vps)
+
+### Creating a Droplet
+Select `Debian 9` as the Droplet distribution:
+
+<img src="../images/01-create-droplet-distro.jpg"
+     width="500px"
+     alt="Droplet distribution" />
+
+Choose a region that is geographically close to you:
+
+<img src="../images/02-create-droplet-region.jpg"
+     width="500px"
+     alt="Droplet region" />
+
+Choose a Droplet size that corresponds to your usage and budget:
+
+<img src="../images/03-create-droplet-size.jpg"
+     width="500px"
+     alt="Droplet size" />
+
+Finalize the Droplet creation:
+
+<img src="../images/04-finalize.jpg"
+     width="500px"
+     alt="Droplet finalization" />
+
+Droplet information is displayed on the Control Panel:
+
+<img src="../images/05-droplet.jpg"
+     width="500px"
+     alt="Droplet summary" />
+
+Once your VPS has been created, you will receive an e-mail with connection
+instructions.
+
+## Obtaining a domain name
+After creating your VPS, it will be reachable using its IP address; some hosting
+providers also create a DNS record, e.g. `ns4853142.ip-01-47-127.eu`.
+
+A domain name (DNS record) is required to obtain a certificate and setup HTTPS
+(HTTP with TLS encryption).
+
+Domain names can be obtained from registrars through hosting providers such as
+[Gandi](https://www.gandi.net/en/domain).
+
+Once you have your own domain, you need to create a new DNS record that points
+to your VPS' IP address:
+
+<img src="../images/06-domain.jpg"
+     width="650px"
+     alt="Domain configuration" />
+
+## Host setup
+Now's the time to connect to your freshly created VPS!
+
+```shell
+$ ssh root@188.166.85.8
+
+Linux stretch-shaarli-02 4.9.0-6-amd64 #1 SMP Debian 4.9.88-1+deb9u1 (2018-05-07) x86_64
+
+The programs included with the Debian GNU/Linux system are free software;
+the exact distribution terms for each program are described in the
+individual files in /usr/share/doc/*/copyright.
+
+Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
+permitted by applicable law.
+Last login: Sun Jul  1 11:20:18 2018 from <REDACTED>
+
+root@stretch-shaarli-02:~$
+```
+
+### Updating the system
+```shell
+root@stretch-shaarli-02:~$ apt update && apt upgrade -y
+```
+
+### Setting up Docker
+_The following instructions are from the
+[Get Docker CE for Debian](https://docs.docker.com/install/linux/docker-ce/debian/)
+guide._
+
+Install package dependencies:
+
+```shell
+root@stretch-shaarli-02:~$ apt install -y apt-transport-https ca-certificates curl gnupg2 software-properties-common
+```
+
+Add Docker's package repository GPG key:
+
+```shell
+root@stretch-shaarli-02:~$ curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add -
+```
+
+Add Docker's package repository:
+
+```shell
+root@stretch-shaarli-02:~$ add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/debian stretch stable"
+```
+
+Update package lists and install Docker:
+
+```shell
+root@stretch-shaarli-02:~$ apt update && apt install -y docker-ce
+```
+
+Verify Docker is properly configured by running the `hello-world` image:
+
+```shell
+root@stretch-shaarli-02:~$ docker run hello-world
+```
+
+### Setting up Docker Compose
+_The following instructions are from the
+[Install Docker Compose](https://docs.docker.com/compose/install/)
+guide._
+
+Download the current version from the release page:
+
+```shell
+root@stretch-shaarli-02:~$ curl -L https://github.com/docker/compose/releases/download/1.21.2/docker-compose-$(uname -s)-$(uname -m) -o /usr/local/bin/docker-compose
+root@stretch-shaarli-02:~$ chmod +x /usr/local/bin/docker-compose
+```
+
+## Running Shaarli
+Shaarli comes with a configuration file for Docker Compose, that will setup:
+
+- a local Docker network
+- a Docker [volume](https://docs.docker.com/storage/volumes/) to store Shaarli data
+- a Docker [volume](https://docs.docker.com/storage/volumes/) to store Træfik TLS configuration and certificates
+- a [Shaarli](https://hub.docker.com/r/shaarli/shaarli/) instance
+- a [Træfik](https://hub.docker.com/_/traefik/) instance
+
+[Træfik](https://docs.traefik.io/) is a modern HTTP reverse proxy, with native
+support for Docker and [Let's Encrypt](https://letsencrypt.org/).
+
+### Compose configuration
+Create a new directory to store the configuration:
+
+```shell
+root@stretch-shaarli-02:~$ mkdir shaarli && cd shaarli
+root@stretch-shaarli-02:~/shaarli$
+```
+
+Download the current version of Shaarli's `docker-compose.yml`:
+
+```shell
+root@stretch-shaarli-02:~/shaarli$ curl -L https://raw.githubusercontent.com/shaarli/Shaarli/master/docker-compose.yml -o docker-compose.yml
+```
+
+Create the `.env` file and fill in your VPS and domain information (replace
+`<MY_SHAARLI_DOMAIN>` and `<MY_CONTACT_EMAIL>` with your actual information):
+
+```shell
+root@stretch-shaarli-02:~/shaarli$ vim .env
+```
+
+```shell
+SHAARLI_VIRTUAL_HOST=<MY_SHAARLI_DOMAIN>
+SHAARLI_LETSENCRYPT_EMAIL=<MY_CONTACT_EMAIL>
+```
+
+### Pull the Docker images
+```shell
+root@stretch-shaarli-02:~/shaarli$ docker-compose pull
+Pulling shaarli ... done
+Pulling traefik ... done
+```
+
+### Run!
+```shell
+root@stretch-shaarli-02:~/shaarli$ docker-compose up -d
+Creating network "shaarli_http-proxy" with the default driver
+Creating volume "shaarli_traefik-acme" with default driver
+Creating volume "shaarli_shaarli-data" with default driver
+Creating shaarli_shaarli_1 ... done
+Creating shaarli_traefik_1 ... done
+```
+
+## Conclusion
+Congratulations! Your Shaarli instance should be up and running, and available
+at `https://<MY_SHAARLI_DOMAIN>`.
+
+<img src="../images/07-installation.jpg"
+     width="500px"
+     alt="Shaarli installation page" />
+
+## Resources
+### Related Shaarli documentation
+- [Docker 101](../docker/docker-101.md)
+- [Shaarli images](../docker/shaarli-images.md)
+
+### Hosting providers
+- [DigitalOcean](https://www.digitalocean.com/)
+- [Gandi](https://www.gandi.net/en)
+- [OVH](https://www.ovh.co.uk/)
+- [RackSpace](https://www.rackspace.com/)
+- etc.
+
+### Domain Names and Registrars
+- [Introduction to the Domain Name System (DNS)](https://opensource.com/article/17/4/introduction-domain-name-system-dns)
+- [ICANN](https://www.icann.org/)
+- [Domain name registrar](https://en.wikipedia.org/wiki/Domain_name_registrar)
+- [OVH Domain Registration](https://www.ovh.co.uk/domains/)
+- [Gandi Domain Registration](https://www.gandi.net/en/domain)
+
+### HTTPS and Security
+- [Transport Layer Security](https://en.wikipedia.org/wiki/Transport_Layer_Security)
+- [Let's Encrypt](https://letsencrypt.org/)
+
+### Docker
+- [Docker Overview](https://docs.docker.com/engine/docker-overview/)
+- [Docker Documentation](https://docs.docker.com/)
+- [Get Docker CE for Debian](https://docs.docker.com/install/linux/docker-ce/debian/)
+- [docker logs](https://docs.docker.com/engine/reference/commandline/logs/)
+- [Volumes](https://docs.docker.com/storage/volumes/)
+- [Install Docker Compose](https://docs.docker.com/compose/install/)
+- [docker-compose logs](https://docs.docker.com/compose/reference/logs/)
+
+### Træfik
+- [Getting Started](https://docs.traefik.io/)
+- [Docker backend](https://docs.traefik.io/configuration/backends/docker/)
+- [Let's Encrypt and Docker](https://docs.traefik.io/user-guide/docker-and-lets-encrypt/)
+- [traefik](https://hub.docker.com/_/traefik/) Docker image
diff --git a/doc/md/Various-hacks.md b/doc/md/guides/various-hacks.md
index 0074ae9f..0074ae9f 100644
--- a/doc/md/Various-hacks.md
+++ b/doc/md/guides/various-hacks.md
diff --git a/docker-compose.yml b/docker-compose.yml
new file mode 100644
index 00000000..e8ea4271
--- /dev/null
+++ b/docker-compose.yml
@@ -0,0 +1,61 @@
+---
+# Shaarli - Docker Compose example configuration
+#
+# See:
+# - https://shaarli.readthedocs.io/en/master/docker/shaarli-images/
+# - https://shaarli.readthedocs.io/en/master/guides/install-shaarli-with-debian9-and-docker/
+#
+# Environment variables:
+# - SHAARLI_VIRTUAL_HOST      Fully Qualified Domain Name for the Shaarli instance
+# - SHAARLI_LETSENCRYPT_EMAIL Contact email for certificate renewal
+version: '3'
+
+networks:
+  http-proxy:
+
+volumes:
+  traefik-acme:
+  shaarli-cache:
+  shaarli-data:
+
+services:
+  shaarli:
+    image: shaarli/shaarli:master
+    build: ./
+    networks:
+      - http-proxy
+    volumes:
+      - shaarli-cache:/var/www/shaarli/cache
+      - shaarli-data:/var/www/shaarli/data
+    labels:
+      traefik.domain: "${SHAARLI_VIRTUAL_HOST}"
+      traefik.backend: shaarli
+      traefik.frontend.rule: "Host:${SHAARLI_VIRTUAL_HOST}"
+
+  traefik:
+    image: traefik
+    command:
+      - "--defaultentrypoints=http,https"
+      - "--entrypoints=Name:http Address::80 Redirect.EntryPoint:https"
+      - "--entrypoints=Name:https Address::443 TLS"
+      - "--retry"
+      - "--docker"
+      - "--docker.domain=docker.localhost"
+      - "--docker.exposedbydefault=true"
+      - "--docker.watch=true"
+      - "--acme"
+      - "--acme.domains=${SHAARLI_VIRTUAL_HOST}"
+      - "--acme.email=${SHAARLI_LETSENCRYPT_EMAIL}"
+      - "--acme.entrypoint=https"
+      - "--acme.onhostrule=true"
+      - "--acme.storage=/acme/acme.json"
+      - "--acme.httpchallenge"
+      - "--acme.httpchallenge.entrypoint=http"
+    networks:
+      - http-proxy
+    ports:
+      - 80:80
+      - 443:443
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+      - traefik-acme:/acme
diff --git a/index.php b/index.php
index ac0baf7d..1480bbc5 100644
--- a/index.php
+++ b/index.php
@@ -1121,7 +1121,7 @@ function renderPage($conf, $pluginManager, $LINKSDB, $history, $sessionManager,
         // Linkdate is kept here to:
         //   - use the same permalink for notes as they're displayed when creating them
         //   - let users hack creation date of their posts
-        //     See: https://shaarli.readthedocs.io/en/master/Various-hacks/#changing-the-timestamp-for-a-shaare
+        //     See: https://shaarli.readthedocs.io/en/master/guides/various-hacks/#changing-the-timestamp-for-a-shaare
         $linkdate = escape($_POST['lf_linkdate']);
         if (isset($LINKSDB[$id])) {
             // Edit
@@ -1845,6 +1845,12 @@ $app->group('/api/v1', function() {
     $this->post('/links', '\Shaarli\Api\Controllers\Links:postLink')->setName('postLink');
     $this->put('/links/{id:[\d]+}', '\Shaarli\Api\Controllers\Links:putLink')->setName('putLink');
     $this->delete('/links/{id:[\d]+}', '\Shaarli\Api\Controllers\Links:deleteLink')->setName('deleteLink');
+
+    $this->get('/tags', '\Shaarli\Api\Controllers\Tags:getTags')->setName('getTags');
+    $this->get('/tags/{tagName:[\w]+}', '\Shaarli\Api\Controllers\Tags:getTag')->setName('getTag');
+    $this->put('/tags/{tagName:[\w]+}', '\Shaarli\Api\Controllers\Tags:putTag')->setName('putTag');
+    $this->delete('/tags/{tagName:[\w]+}', '\Shaarli\Api\Controllers\Tags:deleteTag')->setName('deleteTag');
+
     $this->get('/history', '\Shaarli\Api\Controllers\History:getHistory')->setName('getHistory');
 })->add('\Shaarli\Api\ApiMiddleware');
 
diff --git a/mkdocs.yml b/mkdocs.yml
index d03bc149..941fce3a 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -5,7 +5,10 @@ site_description: The personal, minimalist, super-fast, database free, bookmarki
 theme: readthedocs
 docs_dir: doc/md
 site_dir: doc/html
-strict: true
+# Disable strict mode until ReadTheDocs provides up-to-date MkDocs settings:
+# - https://github.com/shaarli/Shaarli/issues/1179
+# - https://github.com/rtfd/readthedocs.org/issues/4314
+# strict: true
 
 pages:
 - Home: index.md
@@ -27,9 +30,10 @@ pages:
     - RSS feeds: RSS-feeds.md
     - REST API: REST-API.md
     - Community & Related software: Community-&-Related-software.md
-- How To:
-    - Backup, restore, import and export: Backup,-restore,-import-and-export.md
-    - Various hacks: Various-hacks.md
+- Guides:
+    - Install Shaarli on Debian 9 with Docker: guides/install-shaarli-with-debian9-and-docker.md
+    - Backup, restore, import and export: guides/backup-restore-import-export.md
+    - Various hacks: guides/various-hacks.md
 - Development:
     - Development guidelines: Development-guidelines.md
     - Continuous integration tools: Continuous-integration-tools.md
diff --git a/tests/api/controllers/HistoryTest.php b/tests/api/controllers/history/HistoryTest.php
index 61046d97..61046d97 100644
--- a/tests/api/controllers/HistoryTest.php
+++ b/tests/api/controllers/history/HistoryTest.php
diff --git a/tests/api/controllers/InfoTest.php b/tests/api/controllers/info/InfoTest.php
index f7e63bfa..f7e63bfa 100644
--- a/tests/api/controllers/InfoTest.php
+++ b/tests/api/controllers/info/InfoTest.php
diff --git a/tests/api/controllers/DeleteLinkTest.php b/tests/api/controllers/links/DeleteLinkTest.php
index 7d797137..7d797137 100644
--- a/tests/api/controllers/DeleteLinkTest.php
+++ b/tests/api/controllers/links/DeleteLinkTest.php
diff --git a/tests/api/controllers/GetLinkIdTest.php b/tests/api/controllers/links/GetLinkIdTest.php
index 57528d5a..57528d5a 100644
--- a/tests/api/controllers/GetLinkIdTest.php
+++ b/tests/api/controllers/links/GetLinkIdTest.php
diff --git a/tests/api/controllers/GetLinksTest.php b/tests/api/controllers/links/GetLinksTest.php
index d22ed3bf..d22ed3bf 100644
--- a/tests/api/controllers/GetLinksTest.php
+++ b/tests/api/controllers/links/GetLinksTest.php
diff --git a/tests/api/controllers/PostLinkTest.php b/tests/api/controllers/links/PostLinkTest.php
index 100a9170..100a9170 100644
--- a/tests/api/controllers/PostLinkTest.php
+++ b/tests/api/controllers/links/PostLinkTest.php
diff --git a/tests/api/controllers/PutLinkTest.php b/tests/api/controllers/links/PutLinkTest.php
index 8a562571..8a562571 100644
--- a/tests/api/controllers/PutLinkTest.php
+++ b/tests/api/controllers/links/PutLinkTest.php
diff --git a/tests/api/controllers/tags/DeleteTagTest.php b/tests/api/controllers/tags/DeleteTagTest.php
new file mode 100644
index 00000000..e0787ce2
--- /dev/null
+++ b/tests/api/controllers/tags/DeleteTagTest.php
@@ -0,0 +1,164 @@
+<?php
+
+
+namespace Shaarli\Api\Controllers;
+
+use Shaarli\Config\ConfigManager;
+use Slim\Container;
+use Slim\Http\Environment;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+class DeleteTagTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var string datastore to test write operations
+     */
+    protected static $testDatastore = 'sandbox/datastore.php';
+
+    /**
+     * @var string datastore to test write operations
+     */
+    protected static $testHistory = 'sandbox/history.php';
+
+    /**
+     * @var ConfigManager instance
+     */
+    protected $conf;
+
+    /**
+     * @var \ReferenceLinkDB instance.
+     */
+    protected $refDB = null;
+
+    /**
+     * @var \LinkDB instance.
+     */
+    protected $linkDB;
+
+    /**
+     * @var \History instance.
+     */
+    protected $history;
+
+    /**
+     * @var Container instance.
+     */
+    protected $container;
+
+    /**
+     * @var Tags controller instance.
+     */
+    protected $controller;
+
+    /**
+     * Before each test, instantiate a new Api with its config, plugins and links.
+     */
+    public function setUp()
+    {
+        $this->conf = new ConfigManager('tests/utils/config/configJson');
+        $this->refDB = new \ReferenceLinkDB();
+        $this->refDB->write(self::$testDatastore);
+        $this->linkDB = new \LinkDB(self::$testDatastore, true, false);
+        $refHistory = new \ReferenceHistory();
+        $refHistory->write(self::$testHistory);
+        $this->history = new \History(self::$testHistory);
+        $this->container = new Container();
+        $this->container['conf'] = $this->conf;
+        $this->container['db'] = $this->linkDB;
+        $this->container['history'] = $this->history;
+
+        $this->controller = new Tags($this->container);
+    }
+
+    /**
+     * After each test, remove the test datastore.
+     */
+    public function tearDown()
+    {
+        @unlink(self::$testDatastore);
+        @unlink(self::$testHistory);
+    }
+
+    /**
+     * Test DELETE tag endpoint: the tag should be removed.
+     */
+    public function testDeleteTagValid()
+    {
+        $tagName = 'gnu';
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertTrue($tags[$tagName] > 0);
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'DELETE',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $response = $this->controller->deleteTag($request, new Response(), ['tagName' => $tagName]);
+        $this->assertEquals(204, $response->getStatusCode());
+        $this->assertEmpty((string) $response->getBody());
+
+        $this->linkDB = new \LinkDB(self::$testDatastore, true, false);
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertFalse(isset($tags[$tagName]));
+
+        // 2 links affected
+        $historyEntry = $this->history->getHistory()[0];
+        $this->assertEquals(\History::UPDATED, $historyEntry['event']);
+        $this->assertTrue(
+            (new \DateTime())->add(\DateInterval::createFromDateString('-5 seconds')) < $historyEntry['datetime']
+        );
+        $historyEntry = $this->history->getHistory()[1];
+        $this->assertEquals(\History::UPDATED, $historyEntry['event']);
+        $this->assertTrue(
+            (new \DateTime())->add(\DateInterval::createFromDateString('-5 seconds')) < $historyEntry['datetime']
+        );
+    }
+
+    /**
+     * Test DELETE tag endpoint: the tag should be removed.
+     */
+    public function testDeleteTagCaseSensitivity()
+    {
+        $tagName = 'sTuff';
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertTrue($tags[$tagName] > 0);
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'DELETE',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $response = $this->controller->deleteTag($request, new Response(), ['tagName' => $tagName]);
+        $this->assertEquals(204, $response->getStatusCode());
+        $this->assertEmpty((string) $response->getBody());
+
+        $this->linkDB = new \LinkDB(self::$testDatastore, true, false);
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertFalse(isset($tags[$tagName]));
+        $this->assertTrue($tags[strtolower($tagName)] > 0);
+
+        $historyEntry = $this->history->getHistory()[0];
+        $this->assertEquals(\History::UPDATED, $historyEntry['event']);
+        $this->assertTrue(
+            (new \DateTime())->add(\DateInterval::createFromDateString('-5 seconds')) < $historyEntry['datetime']
+        );
+    }
+
+    /**
+     * Test DELETE tag endpoint: reach not existing tag.
+     *
+     * @expectedException Shaarli\Api\Exceptions\ApiTagNotFoundException
+     * @expectedExceptionMessage Tag not found
+     */
+    public function testDeleteLink404()
+    {
+        $tagName = 'nopenope';
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertFalse(isset($tags[$tagName]));
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'DELETE',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $this->controller->deleteTag($request, new Response(), ['tagName' => $tagName]);
+    }
+}
diff --git a/tests/api/controllers/tags/GetTagNameTest.php b/tests/api/controllers/tags/GetTagNameTest.php
new file mode 100644
index 00000000..afac228e
--- /dev/null
+++ b/tests/api/controllers/tags/GetTagNameTest.php
@@ -0,0 +1,129 @@
+<?php
+
+namespace Shaarli\Api\Controllers;
+
+use Shaarli\Config\ConfigManager;
+
+use Slim\Container;
+use Slim\Http\Environment;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+/**
+ * Class GetTagNameTest
+ *
+ * Test getTag by tag name API service.
+ *
+ * @package Shaarli\Api\Controllers
+ */
+class GetTagNameTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var string datastore to test write operations
+     */
+    protected static $testDatastore = 'sandbox/datastore.php';
+
+    /**
+     * @var ConfigManager instance
+     */
+    protected $conf;
+
+    /**
+     * @var \ReferenceLinkDB instance.
+     */
+    protected $refDB = null;
+
+    /**
+     * @var Container instance.
+     */
+    protected $container;
+
+    /**
+     * @var Tags controller instance.
+     */
+    protected $controller;
+
+    /**
+     * Number of JSON fields per link.
+     */
+    const NB_FIELDS_TAG = 2;
+
+    /**
+     * Before each test, instantiate a new Api with its config, plugins and links.
+     */
+    public function setUp()
+    {
+        $this->conf = new ConfigManager('tests/utils/config/configJson');
+        $this->refDB = new \ReferenceLinkDB();
+        $this->refDB->write(self::$testDatastore);
+
+        $this->container = new Container();
+        $this->container['conf'] = $this->conf;
+        $this->container['db'] = new \LinkDB(self::$testDatastore, true, false);
+        $this->container['history'] = null;
+
+        $this->controller = new Tags($this->container);
+    }
+
+    /**
+     * After each test, remove the test datastore.
+     */
+    public function tearDown()
+    {
+        @unlink(self::$testDatastore);
+    }
+
+    /**
+     * Test basic getTag service: return gnu tag with 2 occurrences.
+     */
+    public function testGetTag()
+    {
+        $tagName = 'gnu';
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $response = $this->controller->getTag($request, new Response(), ['tagName' => $tagName]);
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data));
+        $this->assertEquals($tagName, $data['name']);
+        $this->assertEquals(2, $data['occurrences']);
+    }
+
+    /**
+     * Test getTag service which is not case sensitive: occurrences with both sTuff and stuff
+     */
+    public function testGetTagNotCaseSensitive()
+    {
+        $tagName = 'sTuff';
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $response = $this->controller->getTag($request, new Response(), ['tagName' => $tagName]);
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data));
+        $this->assertEquals($tagName, $data['name']);
+        $this->assertEquals(2, $data['occurrences']);
+    }
+
+    /**
+     * Test basic getTag service: get non existent tag => ApiTagNotFoundException.
+     *
+     * @expectedException Shaarli\Api\Exceptions\ApiTagNotFoundException
+     * @expectedExceptionMessage Tag not found
+     */
+    public function testGetTag404()
+    {
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $this->controller->getTag($request, new Response(), ['tagName' => 'nopenope']);
+    }
+}
diff --git a/tests/api/controllers/tags/GetTagsTest.php b/tests/api/controllers/tags/GetTagsTest.php
new file mode 100644
index 00000000..3fab31b0
--- /dev/null
+++ b/tests/api/controllers/tags/GetTagsTest.php
@@ -0,0 +1,209 @@
+<?php
+namespace Shaarli\Api\Controllers;
+
+use Shaarli\Config\ConfigManager;
+
+use Slim\Container;
+use Slim\Http\Environment;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+/**
+ * Class GetTagsTest
+ *
+ * Test get tag list REST API service.
+ *
+ * @package Shaarli\Api\Controllers
+ */
+class GetTagsTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var string datastore to test write operations
+     */
+    protected static $testDatastore = 'sandbox/datastore.php';
+
+    /**
+     * @var ConfigManager instance
+     */
+    protected $conf;
+
+    /**
+     * @var \ReferenceLinkDB instance.
+     */
+    protected $refDB = null;
+
+    /**
+     * @var Container instance.
+     */
+    protected $container;
+
+    /**
+     * @var \LinkDB instance.
+     */
+    protected $linkDB;
+
+    /**
+     * @var Tags controller instance.
+     */
+    protected $controller;
+
+    /**
+     * Number of JSON field per link.
+     */
+    const NB_FIELDS_TAG = 2;
+
+    /**
+     * Before every test, instantiate a new Api with its config, plugins and links.
+     */
+    public function setUp()
+    {
+        $this->conf = new ConfigManager('tests/utils/config/configJson');
+        $this->refDB = new \ReferenceLinkDB();
+        $this->refDB->write(self::$testDatastore);
+
+        $this->container = new Container();
+        $this->container['conf'] = $this->conf;
+        $this->linkDB = new \LinkDB(self::$testDatastore, true, false);
+        $this->container['db'] = $this->linkDB;
+        $this->container['history'] = null;
+
+        $this->controller = new Tags($this->container);
+    }
+
+    /**
+     * After every test, remove the test datastore.
+     */
+    public function tearDown()
+    {
+        @unlink(self::$testDatastore);
+    }
+
+    /**
+     * Test basic getTags service: returns all tags.
+     */
+    public function testGetTagsAll()
+    {
+        $tags = $this->linkDB->linksCountPerTag();
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $response = $this->controller->getTags($request, new Response());
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(count($tags), count($data));
+
+        // Check order
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[0]));
+        $this->assertEquals('web', $data[0]['name']);
+        $this->assertEquals(4, $data[0]['occurrences']);
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[1]));
+        $this->assertEquals('cartoon', $data[1]['name']);
+        $this->assertEquals(3, $data[1]['occurrences']);
+        // Case insensitive
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[5]));
+        $this->assertEquals('sTuff', $data[5]['name']);
+        $this->assertEquals(2, $data[5]['occurrences']);
+        // End
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[count($data) - 1]));
+        $this->assertEquals('w3c', $data[count($data) - 1]['name']);
+        $this->assertEquals(1, $data[count($data) - 1]['occurrences']);
+    }
+
+    /**
+     * Test getTags service with offset and limit parameter:
+     *   limit=1 and offset=1 should return only the second tag, cartoon with 3 occurrences
+     */
+    public function testGetTagsOffsetLimit()
+    {
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+            'QUERY_STRING' => 'offset=1&limit=1'
+        ]);
+        $request = Request::createFromEnvironment($env);
+        $response = $this->controller->getTags($request, new Response());
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(1, count($data));
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[0]));
+        $this->assertEquals('cartoon', $data[0]['name']);
+        $this->assertEquals(3, $data[0]['occurrences']);
+    }
+
+    /**
+     * Test getTags with limit=all (return all tags).
+     */
+    public function testGetTagsLimitAll()
+    {
+        $tags = $this->linkDB->linksCountPerTag();
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+            'QUERY_STRING' => 'limit=all'
+        ]);
+        $request = Request::createFromEnvironment($env);
+        $response = $this->controller->getTags($request, new Response());
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(count($tags), count($data));
+    }
+
+    /**
+     * Test getTags service with offset and limit parameter:
+     *   limit=1 and offset=1 should not return any tag
+     */
+    public function testGetTagsOffsetTooHigh()
+    {
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+            'QUERY_STRING' => 'offset=100'
+        ]);
+        $request = Request::createFromEnvironment($env);
+        $response = $this->controller->getTags($request, new Response());
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEmpty(count($data));
+    }
+
+    /**
+     * Test getTags with visibility parameter set to private
+     */
+    public function testGetTagsVisibilityPrivate()
+    {
+        $tags = $this->linkDB->linksCountPerTag([], 'private');
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+            'QUERY_STRING' => 'visibility=private'
+        ]);
+        $request = Request::createFromEnvironment($env);
+        $response = $this->controller->getTags($request, new Response());
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(count($tags), count($data));
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[0]));
+        $this->assertEquals('Mercurial', $data[0]['name']);
+        $this->assertEquals(1, $data[0]['occurrences']);
+    }
+
+    /**
+     * Test getTags with visibility parameter set to public
+     */
+    public function testGetTagsVisibilityPublic()
+    {
+        $tags = $this->linkDB->linksCountPerTag([], 'public');
+        $env = Environment::mock(
+            [
+                'REQUEST_METHOD' => 'GET',
+                'QUERY_STRING' => 'visibility=public'
+            ]
+        );
+        $request = Request::createFromEnvironment($env);
+        $response = $this->controller->getTags($request, new Response());
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string)$response->getBody(), true);
+        $this->assertEquals(count($tags), count($data));
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data[0]));
+        $this->assertEquals('web', $data[0]['name']);
+        $this->assertEquals(3, $data[0]['occurrences']);
+    }
+}
diff --git a/tests/api/controllers/tags/PutTagTest.php b/tests/api/controllers/tags/PutTagTest.php
new file mode 100644
index 00000000..6f7dec22
--- /dev/null
+++ b/tests/api/controllers/tags/PutTagTest.php
@@ -0,0 +1,209 @@
+<?php
+
+
+namespace Shaarli\Api\Controllers;
+
+
+use Shaarli\Api\Exceptions\ApiBadParametersException;
+use Shaarli\Config\ConfigManager;
+use Slim\Container;
+use Slim\Http\Environment;
+use Slim\Http\Request;
+use Slim\Http\Response;
+
+class PutTagTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var string datastore to test write operations
+     */
+    protected static $testDatastore = 'sandbox/datastore.php';
+
+    /**
+     * @var string datastore to test write operations
+     */
+    protected static $testHistory = 'sandbox/history.php';
+
+    /**
+     * @var ConfigManager instance
+     */
+    protected $conf;
+
+    /**
+     * @var \ReferenceLinkDB instance.
+     */
+    protected $refDB = null;
+
+    /**
+     * @var \History instance.
+     */
+    protected $history;
+
+    /**
+     * @var Container instance.
+     */
+    protected $container;
+
+    /**
+     * @var \LinkDB instance.
+     */
+    protected $linkDB;
+
+    /**
+     * @var Tags controller instance.
+     */
+    protected $controller;
+
+    /**
+     * Number of JSON field per link.
+     */
+    const NB_FIELDS_TAG = 2;
+
+    /**
+     * Before every test, instantiate a new Api with its config, plugins and links.
+     */
+    public function setUp()
+    {
+        $this->conf = new ConfigManager('tests/utils/config/configJson.json.php');
+        $this->refDB = new \ReferenceLinkDB();
+        $this->refDB->write(self::$testDatastore);
+
+        $refHistory = new \ReferenceHistory();
+        $refHistory->write(self::$testHistory);
+        $this->history = new \History(self::$testHistory);
+
+        $this->container = new Container();
+        $this->container['conf'] = $this->conf;
+        $this->linkDB = new \LinkDB(self::$testDatastore, true, false);
+        $this->container['db'] = $this->linkDB;
+        $this->container['history'] = $this->history;
+
+        $this->controller = new Tags($this->container);
+    }
+
+    /**
+     * After every test, remove the test datastore.
+     */
+    public function tearDown()
+    {
+        @unlink(self::$testDatastore);
+        @unlink(self::$testHistory);
+    }
+
+    /**
+     * Test tags update
+     */
+    public function testPutLinkValid()
+    {
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'PUT',
+        ]);
+        $tagName = 'gnu';
+        $update = ['name' => $newName = 'newtag'];
+        $request = Request::createFromEnvironment($env);
+        $request = $request->withParsedBody($update);
+
+        $response = $this->controller->putTag($request, new Response(), ['tagName' => $tagName]);
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data));
+        $this->assertEquals($newName, $data['name']);
+        $this->assertEquals(2, $data['occurrences']);
+
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertNotTrue(isset($tags[$tagName]));
+        $this->assertEquals(2, $tags[$newName]);
+
+        $historyEntry = $this->history->getHistory()[0];
+        $this->assertEquals(\History::UPDATED, $historyEntry['event']);
+        $this->assertTrue(
+            (new \DateTime())->add(\DateInterval::createFromDateString('-5 seconds')) < $historyEntry['datetime']
+        );
+        $historyEntry = $this->history->getHistory()[1];
+        $this->assertEquals(\History::UPDATED, $historyEntry['event']);
+        $this->assertTrue(
+            (new \DateTime())->add(\DateInterval::createFromDateString('-5 seconds')) < $historyEntry['datetime']
+        );
+    }
+
+    /**
+     * Test tag update with an existing tag: they should be merged
+     */
+    public function testPutTagMerge()
+    {
+        $tagName = 'gnu';
+        $newName = 'w3c';
+
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertEquals(1, $tags[$newName]);
+        $this->assertEquals(2, $tags[$tagName]);
+
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'PUT',
+        ]);
+        $update = ['name' => $newName];
+        $request = Request::createFromEnvironment($env);
+        $request = $request->withParsedBody($update);
+
+        $response = $this->controller->putTag($request, new Response(), ['tagName' => $tagName]);
+        $this->assertEquals(200, $response->getStatusCode());
+        $data = json_decode((string) $response->getBody(), true);
+        $this->assertEquals(self::NB_FIELDS_TAG, count($data));
+        $this->assertEquals($newName, $data['name']);
+        $this->assertEquals(3, $data['occurrences']);
+
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertNotTrue(isset($tags[$tagName]));
+        $this->assertEquals(3, $tags[$newName]);
+    }
+
+    /**
+     * Test tag update with an empty new tag name => ApiBadParametersException
+     *
+     * @expectedException Shaarli\Api\Exceptions\ApiBadParametersException
+     * @expectedExceptionMessage New tag name is required in the request body
+     */
+    public function testPutTagEmpty()
+    {
+        $tagName = 'gnu';
+        $newName = '';
+
+        $tags = $this->linkDB->linksCountPerTag();
+        $this->assertEquals(2, $tags[$tagName]);
+
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'PUT',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'PUT',
+        ]);
+        $update = ['name' => $newName];
+        $request = Request::createFromEnvironment($env);
+        $request = $request->withParsedBody($update);
+
+        try {
+            $this->controller->putTag($request, new Response(), ['tagName' => $tagName]);
+        } catch (ApiBadParametersException $e) {
+            $tags = $this->linkDB->linksCountPerTag();
+            $this->assertEquals(2, $tags[$tagName]);
+            throw $e;
+        }
+    }
+
+    /**
+     * Test tag update on non existent tag => ApiTagNotFoundException.
+     *
+     * @expectedException Shaarli\Api\Exceptions\ApiTagNotFoundException
+     * @expectedExceptionMessage Tag not found
+     */
+    public function testPutTag404()
+    {
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'PUT',
+        ]);
+        $request = Request::createFromEnvironment($env);
+
+        $this->controller->putTag($request, new Response(), ['tagName' => 'nopenope']);
+    }
+}
diff --git a/tpl/default/pluginsadmin.html b/tpl/default/pluginsadmin.html
index 8f2597df..82041972 100644
--- a/tpl/default/pluginsadmin.html
+++ b/tpl/default/pluginsadmin.html
@@ -117,7 +117,7 @@
 
       <div class="center more">
         {"More plugins available"|t}
-        <a href="doc/Community-&-Related-software.html#third-party-plugins">{"in the documentation"|t}</a>.
+        <a href="doc/html/Community-&-Related-software/#third-party-plugins">{"in the documentation"|t}</a>.
       </div>
       <div class="center">
         <input type="submit" value="{'Save'|t}" name="save">
diff --git a/tpl/vintage/page.footer.html b/tpl/vintage/page.footer.html
index f409721e..a3380841 100644
--- a/tpl/vintage/page.footer.html
+++ b/tpl/vintage/page.footer.html
@@ -1,7 +1,7 @@
 <div id="footer">
   <strong><a href="https://github.com/shaarli/Shaarli">Shaarli</a></strong>
   - The personal, minimalist, super-fast, database free, bookmarking service by the Shaarli community
-  - <a href="doc/Home.html" rel="nofollow">Help/documentation</a>
+  - <a href="doc/html/index.html" rel="nofollow">Help/documentation</a>
     {loop="$plugins_footer.text"}
         {$value}
     {/loop}