[devbox] Check packages exist in nix before adding (jetify-com#2447)

loreto · web-flow · commit 02812f414cb7 · 2022-08-12T14:38:58.000-05:00
## Summary
Check whether a package exists in nix or not before adding via `devbox add`
Remove-duplicates so packages are not added twice to the list.

## How was it tested?
Compiled, ran `devbox add`, checked for errors, inspected `devbox.json`

## Is this change backwards-compatible?
Yes
diff --git a/devbox.go b/devbox.go
@@ -38,7 +38,13 @@ func Open(dir string) (*Devbox, error) {
 }
 
 func (d *Devbox) Add(pkgs ...string) error {
-	// TODO: validate packages and detect duplicates.
+	for _, pkg := range pkgs {
+		ok := nix.PkgExists(pkg)
+		if !ok {
+			return errors.Errorf("Package %s not found.", pkg)
+		}
+	}
+	// TODO: detect duplicates
 	d.cfg.Packages = append(d.cfg.Packages, pkgs...)
 	return d.saveCfg()
 }
diff --git a/nix/nix.go b/nix/nix.go
@@ -1,6 +1,9 @@
 package nix
 
 import (
+	"bytes"
+	"encoding/json"
+	"fmt"
 	"os"
 	"os/exec"
 	"strings"
@@ -24,3 +27,54 @@ func Exec(path string, command []string) error {
 	cmd.Dir = path
 	return cmd.Run()
 }
+
+func PkgExists(pkg string) bool {
+	_, found := PkgInfo(pkg)
+	return found
+}
+
+type Info struct {
+	NixName string
+	Name string
+	Version string
+	System string
+}
+
+func PkgInfo(pkg string) (*Info, bool) {
+	buf := new(bytes.Buffer)
+	attr := fmt.Sprintf("nixpkgs.%s", pkg)
+	cmd := exec.Command("nix-env", "--json", "-qa", "-A", attr)
+	cmd.Stdout = buf
+	err := cmd.Run()
+	if err != nil {
+		// nix-env returns an error if the package name is invalid, for now assume
+		// all errors are invalid packages.
+		return nil, false /* not found */
+	}
+	pkgInfo := parseInfo(pkg, buf.Bytes())
+	if pkgInfo == nil {
+		return nil, false /* not found */
+	}
+	return pkgInfo, true /* found */
+}
+
+func parseInfo(pkg string, data []byte) *Info {
+	var results map[string]map[string]any
+	err := json.Unmarshal(data, &results)
+	if err != nil {
+		panic(err)
+	}
+	if len(results) != 1 {
+		panic(fmt.Sprintf("unexpected number of results: %d", len(results)))
+	}
+	for _, result := range results {
+		pkgInfo := &Info{
+			NixName: pkg,
+			Name: result["pname"].(string),
+			Version: result["version"].(string),
+			System: result["system"].(string),
+		}
+		return pkgInfo
+	}
+	return nil
+}
diff --git a/planner/go_planner.go b/planner/go_planner.go
@@ -26,7 +26,7 @@ func (g *GoPlanner) Plan(srcDir string) *BuildPlan {
 		},
 		InstallCommand: "go get",
 		BuildCommand:   "CGO_ENABLED=0 go build -o out",
-		StartCommand:   "GIN_MODE=release ./out", // TODO: Move gin specific stuff elsewhere.
+		StartCommand:   "./out", // TODO: Move gin specific stuff elsewhere.
 	}
 }
 

Original file line number	Diff line number	Diff line change
`@@ -38,7 +38,13 @@ func Open(dir string) (*Devbox, error) {`
`38`	`38`	`}`
`39`	`39`
`40`	`40`	`func (d *Devbox) Add(pkgs ...string) error {`
`41`		`- // TODO: validate packages and detect duplicates.`
	`41`	`+ for _, pkg := range pkgs {`
	`42`	`+ ok := nix.PkgExists(pkg)`
	`43`	`+ if !ok {`
	`44`	`+ return errors.Errorf("Package %s not found.", pkg)`
	`45`	`+ }`
	`46`	`+ }`
	`47`	`+ // TODO: detect duplicates`
`42`	`48`	`d.cfg.Packages = append(d.cfg.Packages, pkgs...)`
`43`	`49`	`return d.saveCfg()`
`44`	`50`	`}`
Original file line number	Diff line number	Diff line change
`@@ -26,7 +26,7 @@ func (g GoPlanner) Plan(srcDir string) BuildPlan {`
`26`	`26`	`},`
`27`	`27`	`InstallCommand: "go get",`
`28`	`28`	`BuildCommand: "CGO_ENABLED=0 go build -o out",`
`29`		`- StartCommand: "GIN_MODE=release ./out", // TODO: Move gin specific stuff elsewhere.`
	`29`	`+ StartCommand: "./out", // TODO: Move gin specific stuff elsewhere.`
`30`	`30`	`}`
`31`	`31`	`}`
`32`	`32`