Move to yaml.v3 and mergo. Refactor config parsing into a package. Refactor SSH connections into a package. Create default YAML directory, and update docs

docs/DETAILS.md

@@ -8,7 +8,7 @@ IPng Networks Router Backup is a SSH-based network device configuration backup t
 
 - **Multi-device support**: Backup multiple routers in a single run
 - **Device type templates**: Define command sets per device type
-- **Configuration includes**: Split large configurations with `!include` directives
+- **Configuration includes**: Split large configurations into many files and merge them at runtime
 - **Flexible authentication**: SSH agent, key files, or password authentication
 - **Selective execution**: Target specific devices with `--host` flags
 - **Automatic file organization**: Output files named by hostname
@@ -17,14 +17,13 @@ IPng Networks Router Backup is a SSH-based network device configuration backup t
 
 ## Configuration File Format
 
-The tool uses a YAML configuration file with two main sections: `types` and `devices`. The configuration supports `!include` directives for organizing large configurations across multiple files.
+The tool uses a YAML configuration file with two main sections: `types` and `devices`. The
+configuration reading multiple files with the `--yaml` flag, merging their contents along the way.
 
 ### Complete Example
 
 **Main configuration** (`config.yaml`):
 ```yaml
-!include device-types.yaml
-
 devices:
   asw100:
     user: admin
@@ -45,7 +44,7 @@ devices:
       - show ip route summary
 ```
 
-**Device types file** (`device-types.yaml`):
+**Device types file** (`00-device-types.yaml`):
 ```yaml
 types:
   srlinux:
@@ -155,7 +154,7 @@ devices:
 
 ### Required Flags
 
-- **`--config`**: Path to YAML configuration file
+- **`--yaml`**: Path to YAML configuration file(s)
 
 ### Optional Flags
 
@@ -171,25 +170,25 @@ devices:
 
 ```bash
 # Basic usage - all devices
-ipng-router-backup --config /etc/ipng-router-backup/config.yaml
+ipng-router-backup --yaml /etc/ipng-router-backup/*.yaml
 
 # Custom output directory
-ipng-router-backup --config config.yaml --output-dir /backup/network
+ipng-router-backup --yaml *.yaml --output-dir /backup/network
 
 # Specific devices only
-ipng-router-backup --config config.yaml --host asw100 --host core-01
+ipng-router-backup --yaml *.yaml --host asw100 --host core-01
 
 # Multiple specific devices
-ipng-router-backup --config config.yaml --host asw100 --host asw120 --host core-01
+ipng-router-backup --yaml *.yaml --host asw100 --host asw120 --host core-01
 
 # Custom SSH port
-ipng-router-backup --config config.yaml --port 2222
+ipng-router-backup --yaml *.yaml --port 2222
 
 # Using password authentication
-ipng-router-backup --config config.yaml --password mypassword
+ipng-router-backup --yaml *.yaml --password mypassword
 
 # Using specific SSH key
-ipng-router-backup --config config.yaml --key-file ~/.ssh/network_key
+ipng-router-backup --yaml *.yaml --key-file ~/.ssh/network_key
 ```
 
 ## SSH Authentication Methods
@@ -206,7 +205,7 @@ eval "$(ssh-agent -s)"
 ssh-add ~/.ssh/id_rsa
 
 # Run backup (will use SSH agent automatically)
-ipng-router-backup --config config.yaml
+ipng-router-backup --yaml *.yaml
 ```
 
 **Advantages:**
@@ -221,7 +220,7 @@ Specify a private key file with `--key-file` or use default locations.
 
 ```bash
 # Explicit key file
-ipng-router-backup --config config.yaml --key-file ~/.ssh/network_key
+ipng-router-backup --yaml *.yaml --key-file ~/.ssh/network_key
 
 # Tool automatically checks these default locations:
 # ~/.ssh/id_rsa
@@ -240,10 +239,10 @@ Use `--password` flag for password-based authentication.
 
 ```bash
 # Command line password (not recommended for scripts)
-ipng-router-backup --config config.yaml --password mypassword
+ipng-router-backup --yaml *.yaml --password mypassword
 
 # Interactive password prompt (when no other auth available)
-ipng-router-backup --config config.yaml
+ipng-router-backup --yaml *.yaml
 # Output: "No SSH key found. Enter SSH password: "
 ```
 
@@ -290,7 +289,7 @@ Software Version     : v25.3.2
 ### Basic Backup All Devices
 
 ```bash
-ipng-router-backup --config /etc/backup/network.yaml --output-dir /backup/$(date +%Y%m%d)
+ipng-router-backup --yaml /etc/backup/*.yaml --output-dir /backup/$(date +%Y%m%d)
 ```
 
 ### Backup Specific Device Types
@@ -299,7 +298,7 @@ Create a config with only the devices you want, or use `--host`:
 
 ```bash
 # Backup only SR Linux devices
-ipng-router-backup --config network.yaml --host asw100 --host asw120 --host asw121
+ipng-router-backup --yaml network.yaml --host asw100 --host asw120 --host asw121
 ```
 
 ### Scheduled Backup with SSH Agent
@@ -317,7 +316,7 @@ BACKUP_DIR="/backup/network/$(date +%Y%m%d)"
 mkdir -p "$BACKUP_DIR"
 
 ipng-router-backup \
-  --config /etc/ipng-router-backup/config.yaml \
+  --yaml /etc/ipng-router-backup/*.yaml \
   --output-dir "$BACKUP_DIR"
 
 # Kill SSH agent
@@ -329,7 +328,7 @@ ssh-agent -k
 ```bash
 # Quick backup of single device with password
 ipng-router-backup \
-  --config emergency.yaml \
+  --yaml emergency.yaml \
   --host core-router-01 \
   --password emergency123 \
   --output-dir /tmp/emergency-backup
@@ -420,7 +419,7 @@ BACKUP_DIR="/backup/network-configs"
 cd "$BACKUP_DIR"
 
 # Run backup
-ipng-router-backup --config config.yaml --output-dir .
+ipng-router-backup --yaml config.yaml --output-dir .
 
 # Commit changes
 git add .
@@ -459,11 +458,11 @@ devices:
 #!/bin/bash
 # Backup with monitoring
 
-if ipng-router-backup --config config.yaml --output-dir /backup; then
+if ipng-router-backup --yaml config.yaml --output-dir /backup; then
     echo "Backup completed successfully" | logger
 else
     echo "Backup failed!" | logger
     # Send alert email
     echo "Network backup failed at $(date)" | mail -s "Backup Alert" admin@company.com
 fi
-```
+```