CLI (#28)

* git: change NewDatabase, now accepts a git.Repository, tests now using a fixture

* cli: basic cli implementation, fake SQL execution

Author: mcuadros

cmd/gitql/main.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/jessevdk/go-flags"
+)
+
+func main() {
+	parser := flags.NewNamedParser("gitql", flags.Default)
+	parser.AddCommand("query", "Execute a SQL query a repository.", "", &CmdQuery{})
+	parser.AddCommand("version", "Show the version information.", "", &CmdVersion{})
+
+	_, err := parser.Parse()
+	if err != nil {
+		if e, ok := err.(*flags.Error); ok && e.Type == flags.ErrCommandRequired {
+			parser.WriteHelp(os.Stdout)
+		}
+
+		os.Exit(1)
+	}
+}
+
+type cmd struct {
+	Verbose bool `short:"v" description:"Activates the verbose mode"`
+}
+
+func (c *cmd) print(format string, a ...interface{}) {
+	if !c.Verbose {
+		return
+	}
+
+	fmt.Printf(format, a...)
+}

cmd/gitql/query.go

@@ -0,0 +1,114 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	gitql "github.com/mvader/gitql/git"
+	"github.com/mvader/gitql/sql"
+
+	"gopkg.in/src-d/go-git.v4"
+)
+
+type CmdQuery struct {
+	cmd
+
+	Path string `short:"p" long:"path" description:"Path where the git repository is located"`
+	Args struct {
+		SQL string `positional-arg-name:"sql" required:"true" description:"SQL query to execute"`
+	} `positional-args:"yes"`
+
+	r  *git.Repository
+	db sql.Database
+}
+
+func (c *CmdQuery) Execute(args []string) error {
+	if err := c.validate(); err != nil {
+		return err
+	}
+
+	if err := c.buildDatabase(); err != nil {
+		return err
+	}
+
+	if err := c.executeQuery(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (c *CmdQuery) validate() error {
+	var err error
+	c.Path, err = findDotGitFolder(c.Path)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+func (c *CmdQuery) buildDatabase() error {
+	c.print("opening %q repository...\n", c.Path)
+
+	var err error
+	c.r, err = git.NewFilesystemRepository(c.Path)
+	if err != nil {
+		return err
+	}
+
+	empty, err := c.r.IsEmpty()
+	if err != nil {
+		return err
+	}
+
+	if empty {
+		return errors.New("error: the repository is empty")
+	}
+
+	head, err := c.r.Head()
+	if err != nil {
+		return err
+	}
+
+	c.print("current HEAD %q\n", head.Hash())
+
+	name := filepath.Base(filepath.Join(c.Path, ".."))
+	c.db = gitql.NewDatabase(name, c.r)
+	return nil
+}
+
+func (c *CmdQuery) executeQuery() error {
+	c.print("executing %q at %q\n", c.Args.SQL, c.db.Name())
+
+	fmt.Println(c.Args.SQL)
+	return nil
+}
+
+func findDotGitFolder(path string) (string, error) {
+	if path == "" {
+		var err error
+		path, err = os.Getwd()
+		if err != nil {
+			return "", err
+		}
+	}
+
+	git := filepath.Join(path, ".git")
+	_, err := os.Stat(git)
+	if err == nil {
+		return git, nil
+	}
+
+	if !os.IsNotExist(err) {
+		return "", err
+	}
+
+	next := filepath.Join(path, "..")
+	if next == path {
+		return "", errors.New("unable to find a git repository")
+	}
+
+	return findDotGitFolder(next)
+}

cmd/gitql/version.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"fmt"
+)
+
+var version string
+var build string
+
+type CmdVersion struct{}
+
+func (c *CmdVersion) Execute(args []string) error {
+	fmt.Printf("gitql (%s) - build %s\n", version, build)
+
+	return nil
+}

git/database.go

@@ -22,11 +22,11 @@ func NewDatabase(name string, r *git.Repository) sql.Database {
 	}
 }
 
-func (d Database) Name() string {
+func (d *Database) Name() string {
 	return d.name
 }
 
-func (d Database) Relations() map[string]sql.PhysicalRelation {
+func (d *Database) Relations() map[string]sql.PhysicalRelation {
 	return map[string]sql.PhysicalRelation{
 		commitsRelationName: d.cr,
 	}

mem/database.go

@@ -3,25 +3,25 @@ package mem
 import "github.com/mvader/gitql/sql"
 
 type Database struct {
-	name string
+	name   string
 	tables map[string]sql.PhysicalRelation
 }
 
 func NewDatabase(name string) Database {
 	return Database{
-		name: name,
+		name:   name,
 		tables: map[string]sql.PhysicalRelation{},
 	}
 }
 
-func (d Database) Name() string {
+func (d *Database) Name() string {
 	return d.name
 }
 
-func (d Database) Relations() map[string]sql.PhysicalRelation {
+func (d *Database) Relations() map[string]sql.PhysicalRelation {
 	return d.tables
 }
 
-func (d Database) AddTable(name string, t *Table) {
+func (d *Database) AddTable(name string, t *Table) {
 	d.tables[name] = t
 }