c#google-translate http-status-code-503 downloadstring

Multi-language Google Translate API is returing (503) Server Unavailable

I am trying to use Google Translate to translate but it gives error Server Unavailable. What my guess is that when I try to put same thing in the address bar we receive a captcha to fill in. If we get thru the captcha than only it downloads a txt file. I am thinking this might be the issue of captcha page and not the Server Unavailable.

Calling Function.

string result = TranslateGoogle("Life is great and one is spoiled when it goes on and on and on", "en", "hi");
Console.WriteLine(result);

TranslateGoogle Function

public string TranslateGoogle(string text, string fromCulture, string toCulture)
{
    fromCulture = fromCulture.ToLower();
    toCulture = toCulture.ToLower();
    string[] tokens = fromCulture.Split('-');
    if(tokens.Length > 1)
        fromCulture = tokens[0];

    tokens = toCulture.Split('-');
    if(tokens.Length > 1)
        toCulture = tokens[0];

    string url = string.Format(@"http://translate.google.com/translate_a/t?client=j&text={0}&hl=en&sl={1}&tl={2}", System.Uri.EscapeDataString(text), fromCulture, toCulture);

    string html = null;
    try
    {
        WebClient web = new WebClient();

        web.Headers.Add(HttpRequestHeader.UserAgent, "Mozilla/5.0");
        web.Headers.Add(HttpRequestHeader.AcceptCharset, "UTF-8");

        web.Encoding = Encoding.UTF8;
        html = web.DownloadString(url);
    }
    catch(Exception ex)
    {
        MessageBox.Show(ex.Message);
        return null;
    }

    string result = Regex.Match(html, "trans\":(\".*?\"),\"", RegexOptions.IgnoreCase).Groups[1].Value;
    return result;
}

Expected Output

{
    "sentences":
    [
        {
            "trans":"जीवन महान है और इस पर और पर और पर चला जाता है जब एक खराब है",
            "orig":"Life is great and one is spoiled when it goes on and on and on",
            "translit":"Jīvana mahāna hai aura isa para aura para aura para calā jātā hai jaba ēka kharāba hai",
            "src_translit":"",
            "backend":0
        }
    ],
    "src":"en",
    "server_time":85
}

This is what I am getting.

"The remote server returned an error: (503) Server Unavailable."

What should I be doing to get the expected output for the program.

Solution

Sorry, this is not an answer(but maybe the community can help and let this become a real answer), but I need to post here because in comment I can't format well.

I tried your example and it seems that google thinks that you are trying to abuse their services, here is what client sends:

GET http://translate.google.com/translate_a/t?client=j&text=Life%20is%20great%20and%20one%20is%20spoiled%20when%20it%20goes%20on%20and%20on%20and%20on&hl=en&sl=en&tl=hi HTTP/1.1
Accept-Charset: UTF-8
User-Agent: Mozilla/5.0
Host: translate.google.com
Proxy-Connection: Keep-Alive

Google sends this request to http://ipv4.google.com/sorry/IndexRedirect?continue=http://translate.google.com/translate_a/t%3Fclient%3Dj%26text%3DLife%2520is%2520great%2520and%2520one%2520is%2520spoiled%2520when%2520it%2520goes%2520on%2520and%2520on%2520and%2520on%26hl%3Den%26sl%3Den%26tl%3Dhi&q=CGMSBFgz6X4YkI3frwUiGQDxp4NLo-2RV2k8i7UPzIRYKSuT5usFkUU

here, if navigated from browser it shows captcha, so I tried navigating the url generated by the program using web browser (Firefox). That's what it shows:

Sorry for the italian, it says that an unusual traffic is coming from the PC. Once you prompt the captcha correctly your browser saves a cookie for the next requests(so you won't get the captcha again) and you are redirected to the translated sentence.

Here is an example of the browser requests on next navigations:

GET http://translate.google.com/translate_a/t?client=j&text=Life%20is%20great%20and%20one%20is%20spoiled%20when%20it%20goes%20on%20and%20on%20and%20on&hl=en&sl=en&tl=hi HTTP/1.1
Host: translate.google.com
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:43.0) Gecko/20100101 Firefox/43.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
DNT: 1
Cookie: NID=71=a__xJqNU4C1oQTkLrMCSL4CLdR_nelc5kbjcUwgvJUBILn2SOHrfUeIg-9vWfy6tRHVh9Z4yXT1dpwnnHIXf5i2NLlCuDn-joB1tpYo_9JM4_zQnaaYO7UCsFoFILogS8G4XTt1M8esMgUnG_JzoMWSG81Q-JfGk1_IQsb5gIHyHcKroJeNEUp4bnMkiOvZgj1Sk; SID=DQAAAP8AAADnhNjYLtZUYSPbm-V_62WNnlSj8pUKPRnUfLR-Fp18gYeyWsC93YgLn5yoy0L3FLPb2_yNM7ysBQPCnqJGCy6Or6i2WLHicMaVFr0_0LT4xM2KECq3F6Nczc6V7RO8G5VYnHNLXjZ4ZqVMRTfG3E-Ljrgq_0zg_bhi1DT2CeWoBgBFSVTh_cyMjjYdCRiPpyEFRAtUp_48EKmd62YzJHyPeD-JfXTvVlyacDavPzl4L5yf1KmJ37c-j_Px8dYVKHn5tE_jAKHcFjJ717mY85bjyyUasTKoPc_w9AhnVQXE-v-jBsT4rvbJ3khIqiddjagnQ6LpVCMrRwZ9OwU2uubG; HSID=AX4zDBkEvzB-ZdrnV; APISID=ZMLtLIl8PnW6C6X2/A20GPxC9NiRmY3t1T; _ga=GA1.3.1956353841.1435321193; PREF=ID=1111111111111111:FF=0:LD=it:TM=1436338644:LM=1437143045:V=1:S=me455Y_9_LyG2PFU; GOOGLE_ABUSE_EXEMPTION=ID=52cecb7a44e552cc:TM=1442301156:C=c:IP=88.51.233.126-:S=APGng0tXDRxFvrRNJHu-uk3IRqKVpJAIIQ
Connection: keep-alive

As a proof if I add this line to the C# code:

web.Headers.Add(HttpRequestHeader.Cookie, "NID=71=a__xJqNU4C1oQTkLrMCSL4CLdR_nelc5kbjcUwgvJUBILn2SOHrfUeIg-9vWfy6tRHVh9Z4yXT1dpwnnHIXf5i2NLlCuDn-joB1tpYo_9JM4_zQnaaYO7UCsFoFILogS8G4XTt1M8esMgUnG_JzoMWSG81Q-JfGk1_IQsb5gIHyHcKroJeNEUp4bnMkiOvZgj1Sk; SID=DQAAAP8AAADnhNjYLtZUYSPbm-V_62WNnlSj8pUKPRnUfLR-Fp18gYeyWsC93YgLn5yoy0L3FLPb2_yNM7ysBQPCnqJGCy6Or6i2WLHicMaVFr0_0LT4xM2KECq3F6Nczc6V7RO8G5VYnHNLXjZ4ZqVMRTfG3E-Ljrgq_0zg_bhi1DT2CeWoBgBFSVTh_cyMjjYdCRiPpyEFRAtUp_48EKmd62YzJHyPeD-JfXTvVlyacDavPzl4L5yf1KmJ37c-j_Px8dYVKHn5tE_jAKHcFjJ717mY85bjyyUasTKoPc_w9AhnVQXE-v-jBsT4rvbJ3khIqiddjagnQ6LpVCMrRwZ9OwU2uubG; HSID=AX4zDBkEvzB-ZdrnV; APISID=ZMLtLIl8PnW6C6X2/A20GPxC9NiRmY3t1T; _ga=GA1.3.1956353841.1435321193; PREF=ID=1111111111111111:FF=0:LD=it:TM=1436338644:LM=1437143045:V=1:S=me455Y_9_LyG2PFU; GOOGLE_ABUSE_EXEMPTION=ID=52cecb7a44e552cc:TM=1442301156:C=c:IP=88.51.233.126-:S=APGng0tXDRxFvrRNJHu-uk3IRqKVpJAIIQ"); //This is the cookie of the request of Firefox

Google sends the translated sentence "जीवन महान है और इस पर और पर और पर चला जाता है जब एक खराब है"

Here is a project that seems to work, it basically add different parameters in the url.

GoogleTranslator works by directly invoking Google's translation API called by its online translation form and parsing the results.