Invoking LMPI

Authentication

x-access-token: {Put your access token here}
x-posix-time: 1363797148
x-signature: rnBCnS6YWHvR5PnkM2J44IobfTGcQL039xkRbosIMe8=
x-traceid: 95b794e7-7f4b-4f20-95b6-a16d4143199e
content-type: application/json; charset=utf-8

x-signature Generation

Payload = [x-posix-time] + [http method] + [request_uri] + [body content]

x-signature = HMAC-SHA256(secret_key, UTF-8 Encoding(Payload))

Payload

x-signature

Base64 ( HMAC-SHA256(secret_key, Payload) )

Request Content

{
    company_id : "17363415-4A9F-4A01-8153-10B8F35B50B1",
    user :
    {
        id : "3CB3C2A5-94C5-4D57-9B97-CF4FCC47FF77",
        login_name : "staygreen_greenery",
        password : "93oap1jv0z"
    }
}

C# Sample Code

// Verify that if a PosixTime is 15 minutes before or after the server time.
// serverTime: Current server time.
// posixStr: A posix string of seconds.
// timeRangeinMinutes: You may specify a time range in minute. Default value is 15 minutes.
// returns: True if the posixStr time is within +-15 minutes range of the given server time.

public static bool VerifyPosixTime(string posixStr, int timeRangeinMinutes = 15)
{
    long posixSeconds;
    if (!Int64.TryParse(posixStr, out posixSeconds)) return false;

    var from = DateTimeToPosixTimestamp(DateTime.UtcNow.AddMinutes(-timeRangeinMinutes));
    var to = DateTimeToPosixTimestamp(DateTime.UtcNow.AddMinutes(timeRangeinMinutes));

    return (posixSeconds >= from) && (posixSeconds <= to);
}

// Methods to convert DateTime to Posix time(seconds) in Unix time stamp.
// dateTime: Unix time stamp to convert.
// returns: Return Unix time stamp as long type.

public static long DateTimeToPosixTimestamp(DateTime dateTime)
{
    TimeSpan unixTimeSpan = (dateTime - new DateTime(1970, 1, 1, 0, 0, 0));
    return (long) unixTimeSpan.TotalSeconds;
}

// Generate a x-signature header value that's required to invoke LMPI API interface.
// secret: The secret key used to hash.
// unixTimestamp: Number of seconds after 1970-01-01 til now.
// method: HTTP method used to invoke LMPI.
// requestUri: The request URI without server host. The request URI should be encoded.
// content: HTTP request content in binary. Pass in null if no content is to be sent to server.
// hexstring: A hexstring of HMAC-SHA256 hashed value will be assigned to this parameter.
// returns: Base64 string encoded x-signature.

public static string GenerateSignature(string secret, long unixTimestamp, string method, string requestUri, byte[] content, out string hexstring)
{
    var posix = unixTimestamp.ToString();
    var payload = posix + method.ToUpper() + requestUri +
        ((content == null) ? "" : CalculateMD5Hash(content));

    HMAC hash = new HMACSHA256();
    hash.Initialize();
    hash.Key = Encoding.UTF8.GetBytes(secret);

    var byteArr = hash.ComputeHash(Encoding.UTF8.GetBytes(payload));
    hexstring = ByteArrayToHexString(byteArr);

    return Convert.ToBase64String(byteArr);
}

// Calculates MD5 Hash of a binary and return it as a BASE64 string.
// input: Binary to be calculated.
// returns: MD5 hashed string result in BASE64.

public static string CalculateMD5Hash(byte[] input)
{
    // step 1, calculate MD5 hash from input
    MD5 md5 = MD5.Create();
    byte[] hash = md5.ComputeHash(input);

    return Convert.ToBase64String(hash);
}

// Converts a byte array into HexString.
// ba: Byte array to be converted.
// returns: HEX String.

public static string ByteArrayToHexString(byte[] ba)
{
    var sb = new StringBuilder(ba.Length*2);
    foreach (var b in ba)
    {
        sb.AppendFormat("{0:x2}", b);
    }
    return sb.ToString();
}