internal: add a crime

Signed-off-by: Xe Iaso <me@xeiaso.net>

1 files changed, 45 insertions, 0 deletions

diff --git a/internal/runjson.go b/internal/runjson.go
new file mode 100644
index 0000000..54fb6eb
--- /dev/null
+++ b/internal/runjson.go
@@ -0,0 +1,45 @@
+package internal
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"os/exec"
+)
+
+// Zilch returns the zero value of a given type.
+func Zilch[T any]() T { return *new(T) }
+
+func RunJSON[T any](ctx context.Context, program string, args ...any) (T, error) {
+	exePath, err := exec.LookPath(program)
+	if err != nil {
+		return Zilch[T](), fmt.Errorf("can't find %s: %w", program, err)
+	}
+
+	var argStr []string
+
+	for _, arg := range args {
+		argStr = append(argStr, fmt.Sprint(arg))
+	}
+
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+
+	cmd := exec.CommandContext(ctx, exePath, argStr...)
+	cmd.Stdout = &stdout
+	cmd.Stderr = &stderr
+
+	if err := cmd.Run(); err != nil {
+		os.Stderr.Write(stderr.Bytes())
+		return Zilch[T](), fmt.Errorf("can't run %s: %w", program, err)
+	}
+
+	var result T
+	if err := json.NewDecoder(&stdout).Decode(&result); err != nil {
+		return Zilch[T](), fmt.Errorf("can't decode json: %w", err)
+	}
+
+	return result, nil
+}