[depot tools] Add generator package for creating deps_gen.go
This is just the former contents of go/depot_tools/deps/generate.go but
wrapped up so that it can be used elsewhere. My plan is to use it in
Skia so that we can pin task drivers in DEPS, update them using a normal
autoroller, and directly use them from gen_tasks.
Bug: b/256860862
Change-Id: Ia63db5685f3f55f3ca081f0ebbcee48458d50649
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/892332
Commit-Queue: Kaylee Lubick <kjlubick@google.com>
Reviewed-by: Kaylee Lubick <kjlubick@google.com>
Auto-Submit: Eric Boren <borenet@google.com>
diff --git a/go/depot_tools/deps/generate.go b/go/depot_tools/deps/generate.go
index 64ef2ae..9c7e589 100644
--- a/go/depot_tools/deps/generate.go
+++ b/go/depot_tools/deps/generate.go
@@ -4,65 +4,9 @@
package main
import (
- "fmt"
- "os"
- "path/filepath"
- "sort"
- "strings"
-
- "go.skia.org/infra/go/depot_tools/deps_parser"
- "go.skia.org/infra/go/sklog"
-)
-
-const (
- targetFile = "deps_gen.go"
- header = `// Code generated by "go run generate.go"; DO NOT EDIT
-
-package deps
-
-import (
- "go.skia.org/infra/go/depot_tools/deps_parser"
-)
-
-var deps = deps_parser.DepsEntries{`
-
- entryTmpl = ` "%s": {
- Id: "%s",
- Version: "%s",
- Path: "%s",
- },`
- footer = `}
-`
+ "go.skia.org/infra/go/depot_tools/generator"
)
func main() {
- cwd, err := os.Getwd()
- if err != nil {
- sklog.Fatal(err)
- }
- depsContents, err := os.ReadFile(filepath.Join(cwd, "..", "..", "..", "DEPS"))
- if err != nil {
- sklog.Fatal(err)
- }
- entries, err := deps_parser.ParseDeps(string(depsContents))
- if err != nil {
- sklog.Fatal(err)
- }
- ids := make([]string, 0, len(entries))
- for id := range entries {
- ids = append(ids, id)
- }
- sort.Strings(ids)
-
- parts := []string{header}
- for _, id := range ids {
- entry := entries[id]
- parts = append(parts, fmt.Sprintf(entryTmpl, entry.Id, entry.Id, entry.Version, entry.Path))
- }
- parts = append(parts, footer)
-
- targetContents := strings.Join(parts, "\n")
- if err := os.WriteFile(targetFile, []byte(targetContents), os.ModePerm); err != nil {
- sklog.Fatal(err)
- }
+ generator.MustGenerate("../../../DEPS")
}
diff --git a/go/depot_tools/generator/BUILD.bazel b/go/depot_tools/generator/BUILD.bazel
new file mode 100644
index 0000000..8c4376c
--- /dev/null
+++ b/go/depot_tools/generator/BUILD.bazel
@@ -0,0 +1,13 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+ name = "generator",
+ srcs = ["generator.go"],
+ importpath = "go.skia.org/infra/go/depot_tools/generator",
+ visibility = ["//visibility:public"],
+ deps = [
+ "//go/depot_tools/deps_parser",
+ "//go/skerr",
+ "//go/sklog",
+ ],
+)
diff --git a/go/depot_tools/generator/generator.go b/go/depot_tools/generator/generator.go
new file mode 100644
index 0000000..224f07f
--- /dev/null
+++ b/go/depot_tools/generator/generator.go
@@ -0,0 +1,90 @@
+package generator
+
+/*
+Package generator provides functionality for generating a source file containing
+DEPS entries. It is designed to require the absolute minimum of boilerplate from
+the caller so that they just need to call MustGenerate, along with the necessary
+go:build / +build comments:
+
+```
+ generator.MustGenerate("../../../DEPS")
+```
+*/
+
+import (
+ "fmt"
+ "os"
+ "path/filepath"
+ "sort"
+ "strings"
+
+ "go.skia.org/infra/go/depot_tools/deps_parser"
+ "go.skia.org/infra/go/skerr"
+ "go.skia.org/infra/go/sklog"
+)
+
+const (
+ targetFile = "deps_gen.go"
+ header = `// Code generated by "go run generate.go"; DO NOT EDIT
+
+package deps
+
+import (
+ "go.skia.org/infra/go/depot_tools/deps_parser"
+)
+
+var deps = deps_parser.DepsEntries{`
+
+ entryTmpl = ` "%s": {
+ Id: "%s",
+ Version: "%s",
+ Path: "%s",
+ },`
+ footer = `}
+`
+)
+
+// Generate creates a deps_gen.go file with the contents of the DEPS file.
+// It assumes that it's being run via "go generate" and therefore the output
+// file is to be written to the current working directory. relPathToDeps is the
+// relative path to the DEPS file from the current working directory.
+func Generate(relPathToDeps string) error {
+ cwd, err := os.Getwd()
+ if err != nil {
+ return skerr.Wrap(err)
+ }
+ depsPath := filepath.Join(cwd, filepath.FromSlash(relPathToDeps))
+ depsContents, err := os.ReadFile(depsPath)
+ if err != nil {
+ return skerr.Wrap(err)
+ }
+ entries, err := deps_parser.ParseDeps(string(depsContents))
+ if err != nil {
+ return skerr.Wrap(err)
+ }
+ ids := make([]string, 0, len(entries))
+ for id := range entries {
+ ids = append(ids, id)
+ }
+ sort.Strings(ids)
+
+ parts := []string{header}
+ for _, id := range ids {
+ entry := entries[id]
+ parts = append(parts, fmt.Sprintf(entryTmpl, entry.Id, entry.Id, entry.Version, entry.Path))
+ }
+ parts = append(parts, footer)
+
+ targetContents := strings.Join(parts, "\n")
+ if err := os.WriteFile(targetFile, []byte(targetContents), os.ModePerm); err != nil {
+ return skerr.Wrap(err)
+ }
+ return nil
+}
+
+// MustGenerate runs Generate and panics if it fails.
+func MustGenerate(relPathToDeps string) {
+ if err := Generate(relPathToDeps); err != nil {
+ sklog.Fatal(err)
+ }
+}
