Docker: show welcome page on port 80 when entrypoint.d is empty.

The entrypoint script now performs a default configuration when no useful files are found in /docker-entrypoint.d/ The default configuration serves a welcome page in response to all requests, using Markdown unless text/html is sent in the Accept header. This provides a useful 'hello world' experience when running a Unit container for the first time.
2023-05-09 22:53:18 +01:00
parent 8ab16f71fe
commit d481801907
5 changed files with 139 additions and 36 deletions
--- a/pkg/docker/docker-entrypoint.sh
+++ b/pkg/docker/docker-entrypoint.sh
@@ -25,8 +25,7 @@ if [ "$1" = "unitd" ] || [ "$1" = "unitd-debug" ]; then
    if /usr/bin/find "/var/lib/unit/" -mindepth 1 -print -quit 2>/dev/null | /bin/grep -q .; then
        echo "$0: /var/lib/unit/ is not empty, skipping initial configuration..."
    else
-        if /usr/bin/find "/docker-entrypoint.d/" -mindepth 1 -print -quit 2>/dev/null | /bin/grep -q .; then
-            echo "$0: /docker-entrypoint.d/ is not empty, launching Unit daemon to perform initial configuration..."
+        echo "$0: Launching Unit daemon to perform initial configuration..."
        /usr/sbin/$1 --control unix:/var/run/control.unit.sock

        for i in $(/usr/bin/seq $WAITLOOPS); do
@@ -39,7 +38,10 @@ if [ "$1" = "unitd" ] || [ "$1" = "unitd-debug" ]; then
        done
        # even when the control socket exists, it does not mean unit has finished initialisation
        # this curl call will get a reply once unit is fully launched
-            /usr/bin/curl -f -s -X GET --unix-socket /var/run/control.unit.sock http://localhost/
+        /usr/bin/curl -s -X GET --unix-socket /var/run/control.unit.sock http://localhost/
+
+        if /usr/bin/find "/docker-entrypoint.d/" -mindepth 1 -print -quit 2>/dev/null | /bin/grep -q .; then
+            echo "$0: /docker-entrypoint.d/ is not empty, applying initial configuration..."

            echo "$0: Looking for certificate bundles in /docker-entrypoint.d/..."
            for f in $(/usr/bin/find /docker-entrypoint.d/ -type f -name "*.pem"); do
@@ -69,6 +71,10 @@ if [ "$1" = "unitd" ] || [ "$1" = "unitd-debug" ]; then
            for f in $(/usr/bin/find /docker-entrypoint.d/ -type f -not -name "*.sh" -not -name "*.json" -not -name "*.pem" -not -name "*.js"); do
                echo "$0: Ignoring $f";
            done
+        else
+            echo "$0: /docker-entrypoint.d/ is empty, creating 'welcome' configuration..."
+            curl_put /usr/share/unit/welcome/welcome.json "config"
+        fi

        echo "$0: Stopping Unit daemon after initial configuration..."
        kill -TERM $(/bin/cat /var/run/unit.pid)
@@ -89,9 +95,6 @@ if [ "$1" = "unitd" ] || [ "$1" = "unitd-debug" ]; then
        echo
        echo "$0: Unit initial configuration complete; ready for start up..."
        echo
-        else
-            echo "$0: /docker-entrypoint.d/ is empty, skipping initial configuration..."
-        fi
    fi
 fi

--- a/pkg/docker/template.Dockerfile
+++ b/pkg/docker/template.Dockerfile
@@ -75,9 +75,10 @@ RUN set -ex \
    && ln -sf /dev/stdout /var/log/unit.log

 COPY docker-entrypoint.sh /usr/local/bin/
+COPY welcome.* /usr/share/unit/welcome/

 STOPSIGNAL SIGTERM

 ENTRYPOINT ["/usr/local/bin/docker-entrypoint.sh"]
-
+EXPOSE 80
 CMD ["unitd", "--no-daemon", "--control", "unix:/var/run/control.unit.sock"]
--- a/pkg/docker/welcome.html
+++ b/pkg/docker/welcome.html
@@ -0,0 +1,45 @@
+<!DOCTYPE html>
+<html>
+    <head>
+        <title>Welcome to NGINX Unit</title>
+        <style type="text/css">
+            body { background: white; color: black; font-family: sans-serif; margin: 2em; line-height: 1.5; }
+            h1,h2 { color: #00974d; }
+            li { margin-bottom: 0.5em; }
+            pre { background-color: beige; padding: 0.4em; }
+            hr { margin-top: 2em; border: 1px solid #00974d; }
+            .indent { margin-left: 1.5em; }
+        </style>
+    </head>
+    <body>
+        <h1>Welcome to NGINX Unit</h1>
+        <p>Congratulations! NGINX Unit is installed and running.</p>
+        <h3>Useful Links</h3>
+        <ul>
+            <li><b><a href="https://unit.nginx.org/configuration/?referer=welcome&platform=docker">https://unit.nginx.org/configuration/</a></b><br>
+                To get started with Unit, see the <em>Configuration</em> docs, starting with
+                the <em>Quick Start</em> guide.</li>
+            <li><b><a href="https://unit.nginx.org/howto/docker/?referer=welcome&platform=docker">https://unit.nginx.org/howto/docker/</a></b><br>
+                For guidance about running <em>Unit in Docker</em> and tips for containerized
+                applications.
+            <li><b><a href="https://github.com/nginx/unit">https://github.com/nginx/unit</a></b><br>
+                See our GitHub repo to browse the code, contribute, or seek help from the
+                <a href="https://github.com/nginx/unit#community">community</a>.</li>
+        </ul>
+
+        <h2>Next steps</h2>
+
+        <h3>Check Current Configuration</h3>
+        <div class="indent">
+        <p>Unit's control API is currently listening for configuration changes
+           on the <a href="https://en.wikipedia.org/wiki/Unix_domain_socket">Unix socket</a> at
+           <b>/var/run/control.unit.sock</b> inside the container.<br>
+           To see the current configuration run:</p>
+        <pre>docker exec -ti <containerID> curl --unix-socket /var/run/control.unit.sock http://localhost/config</pre>
+        </div>
+
+        <hr>
+        <p><a href="https://unit.nginx.org/?referer=welcome&platform=docker">NGINX Unit &mdash; the universal web app server</a><br>
+        NGINX, Inc. &copy; 2023</p>
+    </body>
+</html>
--- a/pkg/docker/welcome.json
+++ b/pkg/docker/welcome.json
@@ -0,0 +1,25 @@
+{
+    "listeners": {
+        "*:80": {
+            "pass": "routes"
+        }
+    },
+
+    "routes": [
+        {
+            "match": {
+                "headers": {
+                    "accept": "*text/html*"
+                }
+            },
+            "action": {
+                "share": "/usr/share/unit/welcome/welcome.html"
+            }
+        },
+        {
+            "action": {
+                "share": "/usr/share/unit/welcome/welcome.md"
+            }
+        }
+    ]
+}
--- a/pkg/docker/welcome.md
+++ b/pkg/docker/welcome.md
@@ -0,0 +1,29 @@
+Welcome to NGINX Unit
+=====================
+
+Congratulations! NGINX Unit is installed and running.
+
+Useful Links
+------------
+
+ * https://unit.nginx.org/
+   - Get started with the 'Configuration' docs, starting with the 'Quick Start' guide.
+
+ * https://unit.nginx.org/howto/docker/
+   - Guidance for running Unit in a container and tips for containerized applications.
+
+ * https://github.com/nginx/unit
+   - See our GitHub repo to browse the code, contribute, or seek help from the community.
+
+Current Configuration
+---------------------
+Unit's control API is currently listening for configuration changes on the Unix socket at
+`/var/run/control.unit.sock` inside the container.
+
+Read the current configuration with
+```
+docker exec -ti <containerID> curl --unix-socket /var/run/control.unit.sock http://localhost/config
+```
+
+---
+NGINX Unit - the universal web app server