keymanager v1: fix payload retrieve for binary data

[kayrus]

Fixes #1492

Now payload state is stored in base64 format in case when it's not the text. In these cases it's responsibility of end user to detect the encoding/content-type and call https://developer.hashicorp.com/terraform/language/functions/base64decode

Payloads with whitespaces and newlines are also supported now, e.g. passwords that have whitespace at the end.

[kayrus]

That's wired. My local tests:

checking payload: "p3\xb2q\x10E\x9e\x1e" vs "cDOycRBFnh4=" decoded("p3\xb2q\x10E\x9e\x1e")

differ from CI tests:

checking payload: "p3�q\x10E�\x1e" vs "cDOycRBFnh4=" decoded("p3\xb2q\x10E\x9e\x1e")

with extra debug added:

func resourceSecretV1PayloadBase64CustomizeDiff(diff *schema.ResourceDiff) error {
        encoding := diff.Get("payload_content_encoding").(string)
        if diff.Id() != "" && diff.HasChange("payload") && encoding == "base64" {
                o, n := diff.GetChange("payload")
                oldPayload := o.(string)
                newPayload := n.(string)

                v, err := base64.StdEncoding.DecodeString(newPayload)
                if err != nil {
                        return fmt.Errorf("The Payload is not in the defined base64 format: %s", err)
                }
                newPayloadDecoded := string(v)

                log.Printf("[DEBUG] checking payload: %q vs %q decoded(%q)", oldPayload, newPayload, newPayloadDecoded)
                if oldPayload == newPayloadDecoded {
                        log.Printf("[DEBUG] payload has not changed. clearing diff")
                        return diff.Clear("payload")
                }
        }

        return nil
}

[kayrus]

I decided to store binary data in base64 to avoid these issues.

[kayrus]

@ozerovandrei @nikParasyr please review
@lcurtis-datto can you test this PR in your environment?

[lcurtis-datto]

This works! Thanks a million for fixing this so quickly.

LGTM

[nikParasyr]

LGTM. is it ready from your side @kayrus? Cause i saw some conversation going on on the related issue

[kayrus]

yes, it's ready.