fix: builder and sdk changes (#81)

## Description

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At least please give us some description what you are trying to achieve and why your change is needed. -->

relates to #1234

## Checklist

- [ ] Issue was linked above
- [ ] Code format was applied: `make fmt`
- [ ] Examples were added / adjusted (see `examples/` directory)
- [x] Docs are up-to-date: `make generate-docs` (will be checked by CI)
- [ ] Unit tests got implemented or updated
- [ ] Acceptance tests got implemented or updated (see e.g. [here](f5f99d1709/stackit/internal/services/dns/dns_acc_test.go))
- [x] Unit tests are passing: `make test` (will be checked by CI)
- [x] No linter issues: `make lint` (will be checked by CI)

Co-authored-by: Marcel S. Henselin <marcel.henselin@stackit.cloud>
Co-authored-by: marcel.henselin <marcel.henselin@stackit.cloud>
Reviewed-on: #81

generator/cmd/publish/versions.go

@@ -0,0 +1,169 @@
+package publish
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"log/slog"
+	"net/http"
+	"net/url"
+	"os"
+)
+
+type Version struct {
+	Version   string     `json:"version"`
+	Protocols []string   `json:"protocols"`
+	Platforms []Platform `json:"platforms"`
+}
+
+type Platform struct {
+	OS   string `json:"os" yaml:"os"`
+	Arch string `json:"arch" yaml:"arch"`
+}
+
+type Data struct {
+	Id       string    `json:"id,omitempty"`
+	Versions []Version `json:"versions"`
+}
+
+func (d *Data) WriteToFile(filePath string) error {
+	// TODO: make it variable
+	d.Id = "tfregistry.sysops.stackit.rocks/mhenselin/stackitprivatepreview"
+
+	jsonString, err := json.Marshal(d)
+	if err != nil {
+		return fmt.Errorf("error encoding data: %w", err)
+	}
+
+	//nolint:gosec // this file is not sensitive, so we can use os.ModePerm
+	err = os.WriteFile(
+		filePath,
+		jsonString,
+		os.ModePerm,
+	)
+	if err != nil {
+		return fmt.Errorf("error writing data: %w", err)
+	}
+	return nil
+}
+
+func (d *Data) AddVersion(v Version) error {
+	var newVersions []Version
+	for _, ver := range d.Versions {
+		if ver.Version != v.Version {
+			newVersions = append(newVersions, ver)
+		}
+	}
+	newVersions = append(newVersions, v)
+	d.Versions = newVersions
+	return nil
+}
+
+func (d *Data) Validate() error {
+	for _, v := range d.Versions {
+		err := v.Validate()
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (d *Data) LoadFromFile(filePath string) error {
+	plan, err := os.ReadFile(filePath)
+	if err != nil {
+		return err
+	}
+	err = json.Unmarshal(plan, &d)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (d *Data) LoadFromUrl(uri string) error {
+	u, err := url.ParseRequestURI(uri)
+	if err != nil {
+		return err
+	}
+
+	file, err := os.CreateTemp("", "versions.*.json")
+	if err != nil {
+		return err
+	}
+	defer func(name string) {
+		//nolint:gosec // The file path is generated by os.CreateTemp and is not user-controllable
+		err := os.Remove(name)
+		if err != nil {
+			slog.Error("failed to remove temporary file", slog.Any("err", err))
+		}
+	}(file.Name()) // Clean up
+
+	err = DownloadFile(
+		u.String(),
+		file.Name(),
+	)
+	if err != nil {
+		return err
+	}
+
+	return d.LoadFromFile(file.Name())
+}
+
+func (v *Version) Validate() error {
+	slog.Warn("validation needs to be implemented")
+	return nil
+}
+
+func (v *Version) AddPlatform(p Platform) error {
+	if p.OS == "" || p.Arch == "" {
+		return fmt.Errorf("OS and Arch MUST NOT be empty")
+	}
+	v.Platforms = append(v.Platforms, p)
+	return nil
+}
+
+func (v *Version) AddProtocol(p string) error {
+	if p == "" {
+		return fmt.Errorf("protocol MUST NOT be empty")
+	}
+	v.Protocols = append(v.Protocols, p)
+	return nil
+}
+
+// DownloadFile will download a url and store it in local filepath.
+// It writes to the destination file as it downloads it, without
+// loading the entire file into memory.
+func DownloadFile(urlValue, filepath string) error {
+	// Create the file
+	//nolint:gosec // path traversal is not a concern here, as the filepath is generated by us and not user input
+	out, err := os.Create(filepath)
+	if err != nil {
+		return err
+	}
+	defer func(out *os.File) {
+		err := out.Close()
+		if err != nil {
+			slog.Error("failed to close file", slog.Any("err", err))
+		}
+	}(out)
+
+	// Get the data
+
+	//nolint:gosec,bodyclose // this is a controlled URL, not user input
+	resp, err := http.Get(urlValue)
+	if err != nil {
+		return err
+	}
+	defer func(Body io.ReadCloser) {
+		_ = Body.Close()
+	}(resp.Body)
+
+	// Write the body to file
+	_, err = io.Copy(out, resp.Body)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}