Invoking API with Access Token


Follow the instructions below to invoke EnOS APIs with the generated access token.

Before You Start

  • Before invoking an EnOS API with the access token, you need to have the values of appKey, appSecret, accessToken, and timestamp ready.

Procedure

Constructing paramsData

  1. Sort all the parameters of the API in the URL by ASCII order.
  2. Concatenate the sorted parameters and their values into a string.
  3. If the API request requires a JSON formatted request body, append the request body after the concatenated string to form the paramsData.

Note

The request body that is included in the paramsData must be identical with what is set in the API request. Otherwise, the verification will fail.


See steps 1 to 3 in Request Steps for sample reference.

Constructing apim-sign

  1. Concatenate the values of accessToken, paramsData, timestamp, and appSecret into a string to form the signData.
  2. Encode the concatenated string signData in UTF-8 format and make a digest by SHA256 algorithm.
  3. Convert the digest to hexadecimal format to generate the encrypted ciphertext apim-sign. See the following pseudo code:
sha256(signData).toLowerCase();


See steps 4 to 5 in Request Steps for sample reference.

Constructing the Request Header

Include the following parameters in the API request header:

apim-accesstoken: accessToken
apim-signature: apim-sign
apim-timestamp: timestamp


See step 6 in Request Steps for sample reference.

Error Codes

Code Description
0 Success
1001 Repeated requests with duplicated encryption.
1002 The appKey does not exist.
1003 The encryption is not valid.
1004 Invalid parameter.
1005 Internal service exception.
1202 The parameter is empty.
1203 The access token has expired.
1204 Failed to refresh access token.

Sample

The following example shows the steps of invoking an API with the access token.

Request URL

https://{apigw-address}/m/v1/b?k3=v3&k1=v1&k2=v2

Request Body

{
  "count": 20,
  "page": 1,
  "desc": "description"
}

Request Parameters

Parameter Value
accessToken xxxxaaaxxxx
appSecret xxxappSecretxxx
timestamp 1572574909697

Request Steps

  1. Sort the parameters k3, k1, k2 in the URL by ASCII order into k1, k2, k3.

  2. Concatenate the sorted parameters and their values into a string, for example, k1v1k2v2k3v3.

  3. Concatenate the string k1v1k2v2k3v3 and the request body to form the paramsData.

    k1v1k2v2k3v3{
"count": 20,
"page": 1,
"desc": "description"
}


  4. Concatenate the values of accessToken, paramsData, timestamp, and appSecret.

    xxxxaaaxxxxk1v1k2v2k3v3{
"count": 20,
"page": 1,
"desc": "description"
}1572574909697xxxappSecretxxx


  5. Encode the above concatenated string in UTF-8 format and make a digest by SHA256 algorithm. Convert the digest to hexadecimal format to generate a signature as the apim-signature.

    59828328f6c1f9771015dc74e4929ae30f518a35a3d2353972c2ea46556fc981


  6. Send the API request, for example:

    curl https://{apigw-address}/m/v1/b?k3=v3&k1=v1&k2=v2 -X POST
-H 'apim-accesstoken:xxxxaaaxxxx'
-H 'apim-signature:59828328f6c1f9771015dc74e4929ae30f518a35a3d2353972c2ea46556fc981'
-H 'apim-timestamp:1572574909697'
-d '{
"count": 20,
"page": 1,
"desc": "description"
}'

Java Request Sample

import okhttp3.*;

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

public class EncryptUtils {

    /**
     * Encryption with Java Class
     *
     * @param str Encrypted string
     * @return
     */
    public static String getSHA256(String str) {
        MessageDigest messageDigest;
        String encodestr = "";
        try {
            messageDigest = MessageDigest.getInstance("SHA-256");
            messageDigest.update(str.getBytes(StandardCharsets.UTF_8));
            encodestr = hexString(messageDigest.digest());
        } catch (NoSuchAlgorithmException e) {
            return encodestr;
        }

        return encodestr;
    }

    private static String hexString(byte[] b) {
        StringBuilder hs = new StringBuilder();
        String stmp;
        for (int n = 0; b != null && n < b.length; n++) {
            stmp = Integer.toHexString(b[n] & 0XFF);
            if (stmp.length() == 1) {
                hs.append('0');
            }
            hs.append(stmp);
        }
        return hs.toString();
    }

    public static void main(String[] args) throws IOException {

        String accssToken = "xxxxaaaxxxx";
        String appSecret = "xxxappSecretxxx";
        long timestamp = 1572574909697L; //System.currentTimeMillis();

        String url = "https://{apigw-address}/m/v1/b?k3=v3&k1=v1&k2=v2";
        String requestBody = "{\n" +
                "  \"count\": 20,\n" +
                "  \"page\": 1,\n" +
                "  \"desc\": \"description\"\n" +
                "}";

        HttpUrl httpUrl = HttpUrl.parse(url);
        if (httpUrl == null) {
            return;
        }

        List<String> keys = new ArrayList<>(httpUrl.queryParameterNames());
        Collections.sort(keys);

        StringBuilder paramsData = new StringBuilder();
        for (String key : keys) {
            String value = httpUrl.queryParameter(key);
            paramsData.append(key).append(value);
        }
        paramsData.append(requestBody);
        String signData = accssToken + paramsData.toString() + timestamp + appSecret;
        String apimSign = getSHA256(signData);

        RequestBody body = FormBody
                .create(MediaType.parse("application/json; charset=utf-8"), requestBody);

        Request request = new Request.Builder().url(url).method("POST", body)
                .addHeader("apim-accesstoken", accssToken)
                .addHeader("apim-signature", apimSign)
                .addHeader("apim-timestamp", timestamp + "")
                .build();

        String res = new OkHttpClient().newCall(request).execute().body().string();
        System.out.println(res);
    }
}