Merge pull request #1 from mauromorales/add-user-lists

Add UserLists

.github/workflows/release.yaml

@@ -1,7 +1,6 @@
 name: goreleaser
 
 on:
-  pull_request:
   push:
     tags:
       - '*'

go.mod

@@ -1,6 +1,6 @@
 module github.com/mauromorales/xpasswd
 
-go 1.22.2
+go 1.20
 
 require (
 	github.com/onsi/ginkgo/v2 v2.17.1

go.sum

@@ -32,7 +32,6 @@ golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/tools v0.17.0 h1:FvmRgNOcs3kOa+T20R1uhfP9F6HgG2mfxDv1vrx1Htc=
 golang.org/x/tools v0.17.0/go.mod h1:xsh6VxdV005rRVaS6SSAf9oiAqljS7UZUacMZ8Bnsps=
 google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
-google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

pkg/users/users.go

@@ -1,12 +1,16 @@
 // Package users provides primitives for user information on a system.
 package users
 
+import (
+	"strconv"
+)
+
 // User is an interface that represents a user on a system
 type User interface {
 	// UID returns the user's unique ID
-	UID() string
+	UID() (int, error)
 	// GID returns the user's group ID
-	GID() string
+	GID() (int, error)
 	// Username returns the user's username
 	Username() string
 	// HomeDir returns the user's home directory
@@ -16,3 +20,75 @@ type User interface {
 	// RealName returns the user's real name
 	RealName() string
 }
+
+type CommonUser struct {
+	uid      string
+	gid      string
+	username string
+	homeDir  string
+	shell    string
+	realName string
+}
+
+func (u CommonUser) UID() (int, error) {
+	return strconv.Atoi(u.uid)
+}
+
+func (u CommonUser) GID() (int, error) {
+	return strconv.Atoi(u.gid)
+}
+
+func (u CommonUser) Username() string {
+	return u.username
+}
+
+func (u CommonUser) HomeDir() string {
+	return u.homeDir
+}
+
+func (u CommonUser) Shell() string {
+	return u.shell
+}
+
+func (u CommonUser) RealName() string {
+	return u.realName
+}
+
+// UserList is an interface that represents a list of users
+type UserList interface {
+	// Get returns a user from the list by username
+	Get(username string) User
+	// GetAll returns all users in the list
+	GetAll() ([]User, error)
+	GenerateUID() int
+	LastUID() int
+	SetPath(path string)
+	Load() error
+}
+
+// CommonUserList is a common implementation of UserList
+type CommonUserList struct {
+	users   []User
+	lastUID int
+}
+
+// Get checks if a user with the given username exists
+func (list CommonUserList) Get(username string) User {
+	for _, user := range list.users {
+		if user.Username() == username {
+			return user
+		}
+	}
+	return nil
+}
+
+func (list CommonUserList) LastUID() int {
+	return list.lastUID
+}
+
+func (list CommonUserList) GenerateUID() int {
+	if len(list.users) == 0 {
+		return 0
+	}
+	return list.lastUID + 1
+}

pkg/users/users_darwin.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"os/exec"
+	"strconv"
 	"strings"
 )
 
@@ -16,12 +17,12 @@ type DarwinUser struct {
 	userShell        string
 }
 
-func (u DarwinUser) UID() string {
-	return u.uniqueID
+func (u DarwinUser) UID() (int, error) {
+	return strconv.Atoi(u.uniqueID)
 }
 
-func (u DarwinUser) GID() string {
-	return u.primaryGroupID
+func (u DarwinUser) GID() (int, error) {
+	return strconv.Atoi(u.primaryGroupID)
 }
 
 func (u DarwinUser) Username() string {
@@ -40,9 +41,26 @@ func (u DarwinUser) RealName() string {
 	return u.realName
 }
 
-// List returns a list of users on a Darwin system
-func List() ([]DarwinUser, error) {
-	users := make([]DarwinUser, 0)
+func NewUserList() UserList {
+	return &DarwinUserList{}
+}
+
+// DarwinUserList is a list of Linux users
+type DarwinUserList struct {
+	CommonUserList
+}
+
+func (l *DarwinUserList) SetPath(path string) {
+}
+
+func (l DarwinUserList) Load() error {
+	_, err := l.GetAll()
+	return err
+}
+
+// GetAll returns a list of users on a Darwin system
+func (l DarwinUserList) GetAll() ([]User, error) {
+	users := make([]User, 0)
 
 	output, err := execDSCL("-readall", "/Users", "UniqueID", "PrimaryGroupID", "RealName", "UserShell", "NFSHomeDirectory", "RecordName")
 	if err != nil {
@@ -54,8 +72,17 @@ func List() ([]DarwinUser, error) {
 	for _, record := range records {
 		user := parseRecord(record)
 		users = append(users, user)
+		uid, err := user.UID()
+		if err != nil {
+			return users, fmt.Errorf("failed to convert UID to int: %w", err)
+		}
+		if uid > l.lastUID {
+			l.lastUID = uid
+		}
 	}
 
+	l.users = users
+
 	return users, nil
 }
 

pkg/users/users_darwin_test.go

@@ -18,8 +18,8 @@ var _ = Describe("ListDarwing", func() {
 		UserShell: /bin/sh`
 
 		got := parseRecord(rootRecord)
-		Expect(got.UID()).To(Equal("0"))
-		Expect(got.GID()).To(Equal("0"))
+		Expect(got.UID()).To(Equal(0))
+		Expect(got.GID()).To(Equal(0))
 		Expect(got.HomeDir()).To(Equal("/var/root"))
 		Expect(got.Shell()).To(Equal("/bin/sh"))
 		Expect(got.Username()).To(Equal("root"))

pkg/users/users_linux.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"fmt"
 	"os"
+	"strconv"
 	"strings"
 )
 
@@ -17,12 +18,22 @@ type LinuxUser struct {
 	interpreter   string
 }
 
-func (u LinuxUser) UID() string {
-	return u.uid
+func NewUserList() UserList {
+	return &LinuxUserList{path: "/etc/passwd"}
 }
 
-func (u LinuxUser) GID() string {
-	return u.gid
+// LinuxUserList is a list of Linux users
+type LinuxUserList struct {
+	CommonUserList
+	path string
+}
+
+func (u LinuxUser) UID() (int, error) {
+	return strconv.Atoi(u.uid)
+}
+
+func (u LinuxUser) GID() (int, error) {
+	return strconv.Atoi(u.gid)
 }
 
 func (u LinuxUser) Username() string {
@@ -41,13 +52,21 @@ func (u LinuxUser) RealName() string {
 	return u.nameOrComment
 }
 
-// List returns a list of users on a Linux system
-func List() ([]User, error) {
+func (l *LinuxUserList) SetPath(path string) {
+	l.path = path
+}
+
+func (l *LinuxUserList) Load() error {
+	_, err := l.GetAll()
+	return err
+}
+
+// GetAll returns all users in the list
+func (l *LinuxUserList) GetAll() ([]User, error) {
 	users := make([]User, 0)
 
-	file, err := os.Open("/etc/passwd")
+	file, err := os.Open(l.path)
 	if err != nil {
-		fmt.Println("Error opening the file:", err)
 		return users, err
 	}
 	defer file.Close()
@@ -77,12 +96,23 @@ func List() ([]User, error) {
 			interpreter:   parts[6],
 		}
 		users = append(users, user)
+
+		uid, err := user.UID()
+		if err != nil {
+			return users, fmt.Errorf("failed to convert UID to int: %w", err)
+		}
+
+		if uid > l.lastUID {
+			l.lastUID = uid
+		}
 	}
 
 	// Check if there were errors during scanning
 	if err := scanner.Err(); err != nil {
 		return users, fmt.Errorf("error reading the file: %w", err)
 	}
 
+	l.users = users
+
 	return users, nil
 }

pkg/users/users_test.go

@@ -0,0 +1,64 @@
+package users
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("users", func() {
+	Describe("Get", func() {
+		var list CommonUserList
+		user := CommonUser{uid: "0", gid: "0", username: "root", homeDir: "/root", shell: "/bin/bash", realName: "root"}
+		users := []User{user}
+
+		Context("when the user is not present in the list", func() {
+			JustBeforeEach(func() {
+				list = CommonUserList{}
+			})
+
+			It("returns nil", func() {
+				got := list.Get("foobar")
+				Expect(got).To(BeNil())
+			})
+		})
+
+		Context("when the user is present", func() {
+			JustBeforeEach(func() {
+				list = CommonUserList{users: users}
+			})
+
+			It("returns the user", func() {
+				got := list.Get("root")
+				Expect(got).To(Equal(user))
+			})
+		})
+	})
+
+	Describe("GenerateUID", func() {
+		var list CommonUserList
+		user := CommonUser{uid: "0", gid: "0", username: "root", homeDir: "/root", shell: "/bin/bash", realName: "root"}
+		users := []User{user}
+
+		Context("when the list is empty", func() {
+			JustBeforeEach(func() {
+				list = CommonUserList{}
+			})
+
+			It("returns 0", func() {
+				got := list.GenerateUID()
+				Expect(got).To(Equal(0))
+			})
+		})
+
+		Context("when the list is not empty", func() {
+			JustBeforeEach(func() {
+				list = CommonUserList{users: users}
+			})
+
+			It("returns the next available UID", func() {
+				got := list.GenerateUID()
+				Expect(got).To(Equal(1))
+			})
+		})
+	})
+})