On 12/10/15 3:14 PM, holo wrote:
Hello
I'm trying to write my first class. I want to use it as module and build
anothers on top of it. I read that default functions attributes are not
inherited. Is it that same for constructor? This is how my class (not
finished) is looking right now:
class credential
{
auto accessKey = environment.get["AWS_ACCESS_KEY"];
auto secretKey = environment.get["AWS_SECRET_KEY"];
}
class sigv4 : credential
{
public:
string method;
string service;
string host;
string region;
string endpoint;
string request_parameters;
string payload;
private:
const algorithm = "AWS4-HMAC-SHA256";
auto currentClock = Clock.currTime(UTC());
auto currentDate = cast(Date)currentClock;
auto curDateStr = currentDate.toISOString;
auto currentTime = cast(TimeOfDay)currentClock;
auto curTimeStr = currentTime.toISOString;
auto xamztime = curDateStr ~ "T" ~ curTimeStr ~ "Z";
auto hmac_sha256(ubyte[] key, ubyte[] msg)
{
auto hmac = hmac!SHA256(key);
hmac.put(msg);
auto digest = hmac.finish;
return digest;
}
auto getSignatureKey(string key, string dateStamp, string
regionName, string serviceName)
{
ubyte[] kString = cast(ubyte[])("AWS4" ~ key);
auto kDate = sign(kString, cast(ubyte[])dateStamp);
auto kRegion = sign(kDate, cast(ubyte[])regionName);
auto kService = sign(kRegion, cast(ubyte[])serviceName);
auto kSigning = sign(kService, cast(ubyte[])"aws4_request");
return kSigning;
}
auto getCanonicalRequest(string canonicalURI, string
canonicalQueryString, string canonicalHeaderString, string signedHeaders)
{
string payloadHash = sha256Of("").toHexString.toLower;
string canonicalRequest = method ~ "\n" ~ canonicalURI ~
"\n" ~ canonicalQueryString ~ "\n" ~ canonicalHeadersString ~ "\n" ~
signedHeaders ~ "\n" ~ payloadHash;
}
this()
{
}
}
I need to set all variables by defaults values from "public" and all
needed by function "getCanonicalRequest". But if i will use that class
to build another should i set defaults again? If yes is there some
solution for it?
//holo
By the looks, I'm guessing you do not have much experience when it comes
to OOP.
I think you are wanting something a bit closer to:
import std.typecons : tuple, TypeTuple;
interface Credential {
string encode(....);
}
class SigV4 : Credential {
this(....) {
....
}
string encode(....) {
}
private:
....
}
TypeTuple!(string, string) AWSKeys() {
import std.process;
return tuple(environment.get("AWS_ACCESS_KEY"),
environment.get("AWS_SECRET_KEY"));
}
