Invoke API with the 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 the `paramsData`¶

Sort all the parameters of the API in the URL by ASCII sort order.
Concatenate the sorted parameters and their values into a string.
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 sent in the API request. Otherwise, the verification will fail.

Constructing the `apim-sign`¶

Concatenate the values of accessToken, paramsData, timestamp, and appSecret into a string to form the signData.
Encode the concatenated string signData in UTF-8 format and make a digest by SHA256 algorithm.
Convert the digest to hexadecimal format to generate the encrypted ciphertext apim-sign. The sample code is as per the below.

sha256(signData).toLowerCase();

Constructing the Request Header¶

Include the following parameters in the API request header.

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

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 the access token.

Sample¶

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¶

Follow the steps below to invoke the API with the access token.

Sort the parameters k3, k1, k2 in the URL by ASCII order into k1, k2, k3.
Concatenate the sorted parameters and their values into a string k1v1k2v2k3v3.
Concatenate the string k1v1k2v2k3v3 and the request body into the following string.
```
k1v1k2v2k3v3{
"count": 20,
"page": 1,
"desc": "Description"
}
```

Concatenate the values of accessToken, paramsData, timestamp, and appSecret into the following string.

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

Encode the above concatenated string in UTF-8 format and make a digest by SHA256 algorithm. Convert the digest to hexadecimal format to generate the signature. Example:
```
59828328f6c1f9771015dc74e4929ae30f518a35a3d2353972c2ea46556fc981
```

Send the API request. 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;

/**
 * @author lixiangxin
 * @date 2019/10/24 18:56
 **/
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);
    }
}