More docs, still WIP

client/config.go

@@ -11,6 +11,7 @@ type Config struct {
 	Subscribe   []struct {
 		Topic   string
 		Command string
+		// If []map[string]string TODO This would be cool
 	}
 }
 

docs/subscribe/cli.md

@@ -23,7 +23,7 @@ you may want to edit the `default-host` option:
 default-host: https://ntfy.myhost.com
 ```
 
-## Sending messages
+## Publish using the ntfy CLI
 You can send messages with the ntfy CLI using the `ntfy publish` command (or any of its aliases `pub`, `send` or 
 `trigger`). There are a lot of examples on the page about [publishing messages](../publish.md), but here are a few
 quick ones:
@@ -45,13 +45,76 @@ quick ones:
         "Somebody just bought the thing that you sell"
     ```
 
+=== "Send at 8:30am"
+    ```
+    ntfy pub --at=8:30am delayed_topic Laterzz
+    ```
+
 === "Triggering a webhook"
     ```
     ntfy trigger mywebhook
     ntfy pub mywebhook
     ```
 
-## Using the systemd service
+## Subscribe using the ntfy CLI
+You can subscribe to topics using `ntfy subscribe`. Depending on how it is called, this command
+will either print or execute a command for every arriving message. There are a few different ways 
+in which the command can be run:
+
+### Stream messages and print JSON
+If run like this `ntfy subscribe TOPIC`, the command prints the JSON representation of every incoming 
+message. This is useful when you have a command that wants to stream-read incoming JSON messages. 
+Unless `--poll` is passed, this command stays open forever.
+
+```
+$ ntfy sub mytopic
+{"id":"nZ8PjH5oox","time":1639971913,"event":"message","topic":"mytopic","message":"hi there"}
+{"id":"sekSLWTujn","time":1639972063,"event":"message","topic":"mytopic","tags":["warning","skull"],"message":"Oh no, something went wrong"}
+```
+
+<figure>
+  <video controls muted autoplay loop width="650" src="../../static/img/cli-subscribe-video-1.mp4"></video>
+  <figcaption>Subscribe in JSON mode</figcaption>
+</figure>
+
+### Execute a command for every incoming message
+If run like this `ntfy subscribe TOPIC COMMAND`, a COMMAND is executed for every incoming messages. 
+The message fields are passed to the command as environment variables and can be used in scripts:
+
+<figure>
+  <video controls muted autoplay loop width="650" src="../../static/img/cli-subscribe-video-2.webm"></video>
+  <figcaption>Execute command on incoming messages</figcaption>
+</figure>
+
+| Variable | Aliases | Description |
+|---|---|---
+| `$NTFY_ID` | `$id` | Unique message ID |
+| `$NTFY_TIME` | `$time` | Unix timestamp of the message delivery |
+| `$NTFY_TOPIC` | `$topic` | Topic name |
+| `$NTFY_MESSAGE` | `$message`, `$m` | Message body |
+| `$NTFY_TITLE` | `$title`, `$t` | Message title |
+| `$NTFY_PRIORITY` | `$priority`, `$p` | Message priority (1=min, 5=max) |
+| `$NTFY_TAGS` | `$tags`, `$ta` | Message tags (comma separated list) |
+   
+     Examples:
+       ntfy sub mytopic 'notify-send "$m"'    # Execute command for incoming messages
+       ntfy sub topic1 /my/script.sh          # Execute script for incoming messages
+
+### Using a config file
+ntfy subscribe --from-config
+Service mode (used in ntfy-client.service). This reads the config file (/etc/ntfy/client.yml
+or ~/.config/ntfy/client.yml) and sets up subscriptions for every topic in the "subscribe:"
+block (see config file).
+
+     Examples: 
+       ntfy sub --from-config                           # Read topics from config file
+       ntfy sub --config=/my/client.yml --from-config   # Read topics from alternate config file
+
+The default config file for all client commands is /etc/ntfy/client.yml (if root user),
+or ~/.config/ntfy/client.yml for all other users.
+
+
+### Using the systemd service
 
 ```
 [Service]