Initial commit

Author: mxey

Diff for: .gitignore

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+/haproxy-config-diff

Diff for: examples/new.cfg

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+global
+	log stdout format raw local0 info
+
+defaults
+	timeout client 10s
+	timeout server 10s
+	timeout connect 5s
+
+
+backend be_proxy
+	server localhost 127.0.0.1:8080
+
+
+# Beispielconfig mit anderem Kommentar
+frontend fe_proxy
+	bind 0.0.0.0:80
+
+	default_backend be_proxy

Diff for: examples/old.cfg

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+global
+	log stdout format raw local0 info
+
+defaults
+	timeout connect 5s
+	timeout server 10s
+	timeout client 20s
+
+# Beispielconfig
+frontend fe_proxy
+	bind 0.0.0.0:80
+
+	default_backend be_proxy
+
+backend be_proxy
+	server localhost 127.0.0.1:8080

Diff for: go.mod

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+module github.com/babiel/haproxy-config-diff
+
+go 1.22.0
+
+require github.com/google/go-cmp v0.6.0

Diff for: go.sum

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+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=

Diff for: main.go

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+// haproxy-config-diff parset 2 HAProxy-Configs (grob),
+// erstellt daraus jeweils eine Datenstruktur
+// und vergleicht dann die 2 Datenstrukturen.
+//
+// Dadurch kann man inhaltliche Änderungen zwischen zwei Configs sehen,
+// aber Änderungen an Formatierungen und (irrelevanter) Reihenfolge werden ignoriert.
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"sort"
+	"strings"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+type config map[string]map[string]section
+type section map[string][]string
+
+func parseConfig(r io.Reader) (*config, error) {
+	cfg := make(config)
+	var currentSection section
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		s := strings.TrimSpace(scanner.Text())
+		if s == "" {
+			continue
+		}
+
+		if strings.HasPrefix(s, "#") {
+			continue
+		}
+
+		keyword, params, _ := strings.Cut(s, " ")
+
+		switch keyword {
+		case "global", "defaults", "listen", "frontend", "backend", "cache", "userlist", "peers":
+			// vorherige Section abschließen.
+			sort.Strings(currentSection["timeout"])
+			sort.Strings(currentSection["acl"])
+			sort.Strings(currentSection["bind"])
+			sort.Strings(currentSection["server"])
+			sort.Strings(currentSection["option"])
+			sort.Strings(currentSection["stats"])
+
+			currentSection = make(section)
+			if cfg[keyword] == nil {
+				cfg[keyword] = make(map[string]section)
+			}
+			cfg[keyword][params] = currentSection
+		default:
+			if currentSection == nil {
+				return nil, fmt.Errorf("keyword %q must be in a section", keyword)
+			}
+			currentSection[keyword] = append(currentSection[keyword], params)
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, err
+	}
+
+	return &cfg, nil
+}
+
+func parseConfigFile(fp string) (*config, error) {
+	f, err := os.Open(fp)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	cfg, err := parseConfig(f)
+	if err != nil {
+		return nil, fmt.Errorf("%s: %v", fp, err)
+	}
+
+	return cfg, nil
+}
+
+func main() {
+	if len(os.Args) != 3 {
+		fmt.Println("Usage: haproxy-config-diff FILE FILE")
+		os.Exit(1)
+	}
+
+	lhs, err := parseConfigFile(os.Args[1])
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	rhs, err := parseConfigFile(os.Args[2])
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	diff := cmp.Diff(lhs, rhs)
+	fmt.Println(diff)
+}