Get Started with EnOS API¶
This tutorial will guide you in your first EnOS API request, with the help of examples.
Prerequisites¶
The following preparations are required to invoke the EnOS API:
Get the service account
Get the service account that can be used for identity authorization when invoking the API. Refer to API Authentication for details.
Get resource permissions
Get the resource permissions by authorizing the service acccount for the applications. Refer to Managing Service Accounts for details.
Using Java SDK¶
To invoke EnOS Cloud APIs or EnOS Edge APIs using Java SDK, you need to install the Java Core SDK (Poseidon). Poseidon supports Java 7 and onwards.
Installation Method¶
Java core SDK (Poseidon)
Open the EnOS SDKs & Tools, download the installation package, and import it to your development environment. If your application uses the pom
project, add the following dependencies to the pom.xml
file (you may need to change the version number):
<dependency>
<groupId>com.enos-iot</groupId>
<artifactId>apim-poseidon</artifactId>
<version>0.2.4</version>
</dependency>
Request Method¶
Synchronous Request
For the GET method, if the API logging feature is disabled, only the result is returned after calling the API. The sample code is as follows:
Poseidon.config(PConfig.init().appKey(accessKey).appSecret(secretKey)) .url("https://{apigw-address}/{service-name}/{api-version}/{api_name}?{param1=value1¶m2=value2}") .method("GET") .sync();
For the GET method, if the API logging feature is enabled, both the request parameters with time stamp and response are returned after calling the API. The sample code is as follows:
Poseidon.config(PConfig.init().appKey(accessKey).appSecret(secretKey).debug()) .url("https://{apigw-address}/{service-name}/{api-version}/{api_name}?{param1=value1¶m2=value2}") .method("GET") .sync();
For the GET method, supports independent path setting. The sample code is as follows:
Poseidon.config(PConfig.init().appKey(accessKey).appSecret(secretKey).debug()) .url("https://{apigw-address}") .path("/{service-name}/{api-version}/{api_name}") .method("GET") .header("") .queryParam("param1","value1") .queryParam("param2","value2") .sync();
Note
.path(xxx) must be called before .queryParam(xxx,xxx).
For the POST method, the sample code is as follows:
Poseidon.config(PConfig.init().accessKey(accessKey).secretKey(secretKey).debug()) .url("https://{apigw-address}/lily/0.0.1/getPublic") .method("POST") .header("Content-Type", "application/json") .header("Cookie", "global_id=IAM_S_S7Yd5WXssqEBCququgzeR9JLNBnWr99S") .requestBody( "{\n" + " \"op\": \"pl\",\n" + " \"offset\": 0,\n" + " \"limit\": 10\n" + "}") .sync();
Note
Request header is optional. Specifications such as the type of request content can be included in the header as needed.
Asynchronous Request
The sample code is as follows:
Poseidon.config(PConfig.init().appKey(accessKey).appSecret(secretKey))
.url("https://{apigw-address}/{service-name}/{api-version}/{api_name}?{param1=value1¶m2=value2}")
.method("GET").async( new PoseidonListener() {
@Override
public void onFailure(String errorMessage) {
// TODO
}
@Override
public void onResponse(String body) {
// TODO
}
});
Support for Request and Response
Request provides the built-in support for the Header, Query, RequestBody, and Path parameters.
Exception Handling
Capture the PoseidonException to view specific API exception issues. For API service errors, refer to the API documentation.
Common error messages and description returned from PoseidonException are as follows:
Code |
Description |
Message |
Cause |
---|---|---|---|
400 |
Bad Request |
Cannot process request body |
Failed to get request body. |
401 |
Unauthorized |
Invalid authentication credentials |
Failed to authenticate the identification. |
403 |
Forbidden |
Your IP address is not allowed |
The IP address is not allowed to access. |
413 |
Payload Too Large |
Request size limit exceeded |
The request size exceeded the limit. |
429 |
Too Many Requests |
API rate limit exceeded |
The number of requests exceeded the API request limit. |
500 |
Internal Server Error |
An unexpected error occurred |
Failed to search from cache. |
503 |
Service unavailable |
Service unavailable |
The service is not allowed to access. |
Invoking EnOS API¶
After the development environment is ready, refer to the parameter descriptions and invocation examples in the API documentation to invoke the API.
Sample 1 - Using Java core SDK (GET Method)¶
The following sample shows how to get the asset details by using the Java core SDK to invoke the Get Asset API (with API logging feature disabled):
import com.enosiot.apim.poseidon.config.PConfig;
import com.enosiot.apim.poseidon.core.Poseidon;
public class GetAsset {
public static void main(String[] args) {
String accessKey = "{access_key_of_the_application}";
String secretKey = "{secret_key_of_the_application}";
String response = Poseidon.config(PConfig.init().appKey(accessKey).appSecret(secretKey))
.url("https://{apigw-address}/asset-service/v2.1/assets?action=get&orgId={org_id}&assetId={asset_id}")
.method("GET")
.sync();
System.out.println(response);
}
}
The returned data sample is as follows:
{
"msg": OK,
"code": 0,
"data": {
"modelId": "model_id",
"assetId": "asset_id",
"timezone": "+08:00",
"name": {
"i18nValue": {},
"defaultValue": "asset_name"
},
"attributes": {
"system": "System"
},
"modelIdPath": null,
"orgId": "yourOrgId",
"desc": null,
"tags": {}
},
"requestId": "9a5cfbac-b2f8-4a37-b38d-8bccdd77d073"
}
Sample 2 - Using Java core SDK (POST Method)¶
The following sample shows how to update the name, description, attributes, timezone, and tags of an asset by using the Java core SDK to invoke the Update Asset API (with API logging feature enabled):
import com.enosiot.apim.poseidon.config.PConfig;
import com.enosiot.apim.poseidon.core.Poseidon;
public class UpdateAsset {
public static void main(String[] args) {
String accessKey = "{access_key_of_the_application}";
String secretKey = "{secret_key_of_the_application}";
String data = "{\"asset\":{\"assetId\":\"{asset_id}\",\"name\":{\"defaultValue\":\"Device_Name\",\"i18nValue\":{\"en_US\":\"Device_Name\",\"zh_CN\":\"Chinese name\"}},\"description\":\"Device_Description\",\"attributes\":{\"Brand\":\"Brand_Name\"},\"timezone\":\"+07:00\",\"tags\":{\"year\":\"2019\",\"site\":\"Site_Name\"}}}";
String response = Poseidon.config(PConfig.init().appKey(accessKey).appSecret(secretKey).debug())
.url("https://{apigw-address}/asset-service/v2.1/assets?action=update&orgId={org_id}")
.method("POST")
.requestBody(data)
.sync();
System.out.println(response);
}
}
The returned data sample is as follows:
2019-7-10 16:35:12 [Poseidon] url: https://{apigw-address}/asset-service/v2.1/assets?action=update&orgId={org_id}
2019-7-10 16:35:12 [Poseidon] method: POST
2019-7-10 16:35:12 [Poseidon] headers: {}
2019-7-10 16:35:12 [Poseidon] requestBody: {"asset":{"assetId":"{asset_id}","name":{"defaultValue":"Device_Name","i18nValue":{"en_US":"Device_Name","zh_CN":"Chinese name"}},"description":"Device_Description","attributes":{"Brand":"Brand_Name"},"timezone":"+07:00","tags":{"year":"2019","site":"Site_Name"}}}
2019-7-10 16:35:13 [Poseidon] responseBody: {"code":0,"msg":"OK","requestId":"9d6b9869-4ffd-4964-a8ff-d150a0d1a91f","data":null}