Rewrite panic to log.Panicf

Author: f0o

.gitignore

@@ -15,3 +15,4 @@ vite.config.ts.timestamp-*
 !config.yaml.example
 protobuf/*
 install.yml
+.gitlab-ci.yml

main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"embed"
 	"io/fs"
+	"log"
 
 	"gitlab.as203038.net/AS203038/looking-glass/server"
 )
@@ -14,7 +15,7 @@ var webemned embed.FS
 func main() {
 	web, err := fs.Sub(webemned, "dist")
 	if err != nil {
-		panic(err)
+		log.Panicln(err)
 	}
 	server.Start(context.Background(), web)
 }

server/routers/frrouting.yml

@@ -1,6 +1,6 @@
 name: frrouting
 
-ping: 
+ping:
     # any:
     #     - ping -n -c5 {{.IP.IP}}
     ipv4:
@@ -17,7 +17,7 @@ traceroute:
         - traceroute -6 -w 1 -q1 -I --back --mtu -e -s {{.Cfg.Source6.IP}} {{.IP.IP}}
 
 bgp:
-    route: 
+    route:
         - vtysh -c 'show bgp vrf {{.Cfg.VRF}} {{.IP.Family}} unicast {{.IP.IP}}'
     community:
         - vtysh -c 'show bgp vrf {{.Cfg.VRF}} ipv4 unicast community {{.Community}}'

server/routers/routers.go

@@ -11,8 +11,11 @@ var (
 )
 
 func register(name string, rt utils.Router) bool {
+	if name == "" {
+		log.Panicln("Router name cannot be empty")
+	}
 	if _, ok := _routers[name]; ok {
-		panic("Router already registered")
+		log.Panicf("Router %s already registered", name)
 	}
 	_routers[name] = rt
 	return true

server/routers/yaml.go

@@ -3,84 +3,132 @@ package routers
 import (
 	"bytes"
 	"embed"
-	"fmt"
+	"log"
+	"os"
+	"strings"
 	"text/template"
 
 	"gitlab.as203038.net/AS203038/looking-glass/server/errs"
 	"gitlab.as203038.net/AS203038/looking-glass/server/utils"
 	yaml "gopkg.in/yaml.v2"
 )
 
+// _tpl_data represents the template data used in the router YAML file.
 type _tpl_data struct {
-	Cfg       *utils.RouterConfig
-	IP        *utils.IPNet
-	Community string
-	ASPath    string
+	Cfg       *utils.RouterConfig // Cfg holds the router configuration.
+	IP        *utils.IPNet        // IP holds the IP network information.
+	Community string              // Community holds the community string.
+	ASPath    string              // ASPath holds the AS path information.
 }
 
+// Yaml represents the structure of a YAML file.
 type Yaml struct {
-	Path     string
+	Path     string // Path represents the file path.
 	Template struct {
-		Name string `yaml:"name"`
+		Name string `yaml:"name"` // Name represents the template name.
 		Ping struct {
-			Any  []string `yaml:"any"`
-			IPv4 []string `yaml:"ipv4"`
-			IPv6 []string `yaml:"ipv6"`
-		} `yaml:"ping"`
+			Any  []string `yaml:"any"`  // Any represents the list of ping targets for any IP address.
+			IPv4 []string `yaml:"ipv4"` // IPv4 represents the list of ping targets for IPv4 addresses.
+			IPv6 []string `yaml:"ipv6"` // IPv6 represents the list of ping targets for IPv6 addresses.
+		} `yaml:"ping"` // Ping represents the ping section in the template.
 		Traceroute struct {
-			Any  []string `yaml:"any"`
-			IPv4 []string `yaml:"ipv4"`
-			IPv6 []string `yaml:"ipv6"`
-		} `yaml:"traceroute"`
+			Any  []string `yaml:"any"`  // Any represents the list of traceroute targets for any IP address.
+			IPv4 []string `yaml:"ipv4"` // IPv4 represents the list of traceroute targets for IPv4 addresses.
+			IPv6 []string `yaml:"ipv6"` // IPv6 represents the list of traceroute targets for IPv6 addresses.
+		} `yaml:"traceroute"` // Traceroute represents the traceroute section in the template.
 		BGP struct {
-			Route     []string `yaml:"route"`
-			Community []string `yaml:"community"`
-			ASPath    []string `yaml:"aspath"`
-		} `yaml:"bgp"`
+			Route     []string `yaml:"route"`     // Route represents the list of BGP routes.
+			Community []string `yaml:"community"` // Community represents the list of BGP communities.
+			ASPath    []string `yaml:"aspath"`    // ASPath represents the list of BGP AS paths.
+		} `yaml:"bgp"` // BGP represents the BGP section in the template.
 	}
 }
 
 //go:embed all:*.yml
 var compiledRouters embed.FS
 
+// init is a function that is automatically called before the program starts.
+// It initializes the routers by loading them from the specified directory and bundled routers.
+// It reads YAML files, unmarshals them into router templates, and registers the routers.
+// If the ROUTER_DIR environment variable is set, it loads routers from the specified directory.
+// If the bundled routers exist, it loads them as well.
+// The function logs the registration status of each router.
 func init() {
-	// Load all routers
+	// Check for ROUTER_DIR environment variable
+	rd := os.Getenv("ROUTER_DIR")
+	if rd != "" {
+		// Load all routers from ROUTER_DIR
+		files, err := os.ReadDir(rd)
+		if err != nil {
+			log.Panicf("Could not Read directory %s: %+v", rd, err)
+		}
+		log.Printf("Loading routers from %s\n", rd)
+		for _, file := range files {
+			if file.IsDir() || (!strings.HasSuffix(file.Name(), ".yml") && !strings.HasSuffix(file.Name(), ".yaml")) {
+				continue
+			}
+			// Rest of the code for processing the file
+			y := &Yaml{Path: file.Name()}
+			yamlFile, err := os.ReadFile(rd + "/" + y.Path)
+			if err != nil {
+				log.Panicf("Could not Read file %s/%s: %+v", rd, y.Path, err)
+			}
+			err = yaml.Unmarshal(yamlFile, &y.Template)
+			if err != nil {
+				log.Panicf("Could not Unmarshal file %s/%s: %+v", rd, y.Path, err)
+			}
+			if y.Template.Name == "" {
+				log.Printf("Router name cannot be empty (%s/%s)", rd, y.Path)
+				continue
+			}
+			register(y.Template.Name, y)
+			log.Printf("Router %s (%s/%s) registered\n", y.Template.Name, rd, y.Path)
+		}
+	}
+
+	// Load all bundled routers
 	files, err := compiledRouters.ReadDir(".")
 	if err != nil {
-		panic(err)
+		log.Panicf("Could not Read builtin directory: %+v", err)
 	}
 	for _, file := range files {
-		y := &Yaml{}
-		y.Path = file.Name()
+		y := &Yaml{Path: file.Name()}
 		yamlFile, err := compiledRouters.ReadFile(y.Path)
 		if err != nil {
-			panic(err)
+			log.Panicf("Could not Read file builtin:%s: %+v", y.Path, err)
 		}
 		err = yaml.Unmarshal(yamlFile, &y.Template)
 		if err != nil {
-			panic(err)
+			log.Panicf("Could not Unmarshal file builtin:%s: %+v", y.Path, err)
+		}
+		if _, ok := _routers[y.Template.Name]; !ok {
+			register(y.Template.Name, y)
+			log.Printf("Router %s (builtin:%s) registered\n", y.Template.Name, y.Path)
+		} else {
+			log.Printf("Router %s already registered\n", y.Template.Name)
 		}
-		register(y.Template.Name, y)
-		fmt.Printf("Router %s registered\n", y.Template.Name)
 	}
 }
 
+// _tpl is a helper function used to generate a list of strings based on the provided template name and data.
+// It takes a template name and data as input and returns a list of strings generated from the template.
+// The function first determines the appropriate template to use based on the template name and the IP version in the data.
+// It then iterates over the selected template(s), executes them with the provided data, and appends the generated strings to the result list.
+// If no template is found for the given name, the function returns nil and an error of type `errs.OperationUnknown`.
 func (rt *Yaml) _tpl(name string, data _tpl_data) ([]string, error) {
 	var tpl []string
 	var ret []string
 	switch name {
 	case "ping":
-		if rt.Template.Ping.Any != nil {
-			tpl = rt.Template.Ping.Any
-		} else if data.IP.IsIPv4() {
+		tpl = rt.Template.Ping.Any
+		if data.IP.IsIPv4() {
 			tpl = rt.Template.Ping.IPv4
 		} else if data.IP.IsIPv6() {
 			tpl = rt.Template.Ping.IPv6
 		}
 	case "traceroute":
-		if rt.Template.Traceroute.Any != nil {
-			tpl = rt.Template.Traceroute.Any
-		} else if data.IP.IsIPv4() {
+		tpl = rt.Template.Traceroute.Any
+		if data.IP.IsIPv4() {
 			tpl = rt.Template.Traceroute.IPv4
 		} else if data.IP.IsIPv6() {
 			tpl = rt.Template.Traceroute.IPv6
@@ -110,22 +158,31 @@ func (rt *Yaml) _tpl(name string, data _tpl_data) ([]string, error) {
 	return ret, nil
 }
 
+// Ping sends a ping request to the specified IP address using the provided router configuration.
+// It returns a slice of strings representing the ping response and an error if any.
 func (rt *Yaml) Ping(cfg *utils.RouterConfig, ip *utils.IPNet) ([]string, error) {
 	return rt._tpl("ping", _tpl_data{Cfg: cfg, IP: ip})
 }
 
+// Traceroute performs a traceroute operation using the provided router configuration and IP address.
+// It returns a slice of strings representing the traceroute results and an error if any.
 func (rt *Yaml) Traceroute(cfg *utils.RouterConfig, ip *utils.IPNet) ([]string, error) {
 	return rt._tpl("traceroute", _tpl_data{Cfg: cfg, IP: ip})
 }
 
+// BGPRoute generates BGP route configuration based on the provided RouterConfig and IPNet.
+// It returns a slice of strings representing the generated configuration and an error if any.
 func (rt *Yaml) BGPRoute(cfg *utils.RouterConfig, ip *utils.IPNet) ([]string, error) {
 	return rt._tpl("bgp.route", _tpl_data{Cfg: cfg, IP: ip})
 }
 
+// BGPCommunity returns a list of strings representing the BGP community values for the given router configuration and community.
 func (rt *Yaml) BGPCommunity(cfg *utils.RouterConfig, community string) ([]string, error) {
 	return rt._tpl("bgp.community", _tpl_data{Cfg: cfg, Community: community})
 }
 
+// BGPASPath returns a slice of strings representing the BGP AS path for the given router configuration and AS path string.
+// It uses the "_tpl" method to render the "bgp.aspath" template with the provided configuration and AS path.
 func (rt *Yaml) BGPASPath(cfg *utils.RouterConfig, aspath string) ([]string, error) {
 	return rt._tpl("bgp.aspath", _tpl_data{Cfg: cfg, ASPath: aspath})
 }