How to access a Spring Cloud Function from a Client Application or Webclient or Postman. The following is the working source code of a Spring Cloud Function and the curl command to access the function. Appreciate if any one can provide a WebClient example that also can call this function. Because the ultimate aim to develop a Spring Function to use within the Client Application.
Spring Cloud Function Source code
#SpringBootApplication
public class CloudFunctionApplication {
public static void main(String[] args) {
SpringApplication.run(CloudFunctionApplication.class, args);
}
#Bean
public Function<String, String> reverseString() {
return value -> new StringBuilder(value).reverse().toString();
}
}
**Curl command to access
**
curl localhost:8080/greeter -H "Content-Type: text/plain" -d "World"
I have tried to access the function from curl command. How to use Webclient of a client application such as React App to use the function ?
Related
I am trying to connect to spring vault using role based authentication (spring boot project).
As per documentation, I should be able to connect to spring vault only using approle (pull mode). However, I am getting secrect-id missing exception on application start up.
http://cloud.spring.io/spring-cloud-vault/single/spring-cloud-vault.html#_approle_authentication
When I pass, secret-id also, I am able to connect and properties/values are getting correctly autowired.
Is there any way I can connect with vault using "token + role/role-id" and spring generate secret-id for me automatically at run time using mentioned info.
spring.cloud.vault:
scheme: http
host: <host url>
port: 80
token : <token>
generic.application-name: vault/abc/pqr/test
generic.backend: <some value>
generic.default-context: vault/abc/pqr/test
token: <security token>
authentication: approle
app-role:
role-id: <role-id>
POM:
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-vault-starter-config</artifactId>
<version>1.0.0.BUILD-SNAPSHOT</version>
</dependency>
Please let me know in case any other info is required.
Update
#mp911de, I tried as per your suggestion, however spring-cloud-vault is picking properties set in bootstrap.yml and not one set inside "onApplicationEvent" and thus solution is not working. I tried setting property by "System.setProperty" method but that event didn't worked.
However, if I am setting properties in main before run method, it is working as expected. But I need to load application.properties first (need to pick some configuration from there) and thus don't want to write logic there.
Is there anything wrong in my approach ??
#Component public class LoadVaultProperties implements ApplicationListener<ApplicationEnvironmentPreparedEvent> {
private RestTemplate restTemplate = new RestTemplate();
#Override
public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
try {
String roleId = getRoleIdForRole(event); //helper method
String secretId = getSecretIdForRoleId(event); //helper method
Properties properties = new Properties();
properties.put("spring.cloud.vault.app-role.secret-id", secretId);
properties.put("spring.cloud.vault.app-role.role-id", roleId);
event.getEnvironment().getPropertySources().addFirst(new PropertiesPropertySource(
PropertySourceBootstrapConfiguration.BOOTSTRAP_PROPERTY_SOURCE_NAME, properties));
} catch (Exception ex) {
throw new IllegalStateException(ex);
}
}
Spring Vault's AppRole authentication supports two modes but not the pull mode:
Push mode in which you need to supply the secret_id
Authenticating without a secret_id by just passing role_id. This mode requires the role to be created without requiring the secret_id by setting bind_secret_id=false on role creation
Pull mode as mention in the Vault documentation requires the client to know about the secret_id, obtained from a wrapped response. Spring Vault does not fetch a wrapped secret_id but I think that would be a decent enhancement.
Update: Setting system properties before application start:
#SpringBootApplication
public class MyApplication {
public static void main(String[] args) {
System.setProperty("spring.cloud.vault.app-role.role-id", "…");
System.setProperty("spring.cloud.vault.app-role.secret-id", "…");
SpringApplication.run(MyApplication.class, args);
}
References:
Vault documentation on AppRole creation
Spring Cloud Vault documentation on AppRole authentication.
I am using the Jersey 2.25.1 Client and can't get any log output. I've looked at the 2.25.1 documentation -
https://www.scribd.com/document/350321996/Jersey-Documentation-2-25-1-User-Guide
- and followed what they described for Client logging -
ClientConfig clientConfig = new ClientConfig();
clientConfig.property(LoggingFeature.LOGGING_FEATURE_VERBOSITY_CLIENT, LoggingFeature.Verbosity.PAYLOAD_ANY);
Client client = ClientBuilder.newClient(clientConfig);
Is there an addition step that I am missing? The request is working as expected. The application is running on a Glassfish server and using SLF4J. My understanding was that the output would be logged to the server.log.
You also need to register a logging Filter
clientConfig.register(new MyLogFilter());
You need to create a log filter
class MyLogFilter implements ClientRequestFilter {
private static final Logger LOG = Logger.getLogger(MyLogFilter.class.getName());
#Override
public void filter(ClientRequestContext requestContext) throws IOException {
LOG.log(Level.INFO, requestContext.getEntity().toString()); // you can configure logging level here
}
}
I novice in camel.
What i have:
- rest app deployed on tomcat
- mongodb
What i want to do:
I want to send request from rest app to camel and camel send request to mongodb and then camel send response to the rest app. (request rest -> camel -> mongodb , response mongodb->camel->rest )
I can't find information about it.
how i can do this?
my Rest class
#Path("/leave")
public class Leave {
#GET
#Path("/all")
#Produces("application/json")
public String getLeaveRequestList(){
return "{\"status\":200}";
}}
my route
public class CamelRouteConfig extends RouteBuilder {
#Override
public void configure() throws Exception {
restConfiguration().host("localhost").port(8080);
rest("/leave")
.post("/all")
.consumes("application/json")
.to("stream:out");
}
}
it do nothing. why? - i have no idea
contex method
CamelRouteConfig routeConfig = new CamelRouteConfig();
CamelContext context = new DefaultCamelContext();
try {
context.addRoutes(routeConfig);
context.start();
}finally {
context.stop();
}
thx for your attention!
You are running Camel as standalone. When you call context.start(), the method does not block. It means that after starting, context.stop() is called immediately. Camel shuts down and REST service goes down with it.
See the following articles: Running Camel standalone and have it keep runninge and running Camel standalone.
Use class org.apache.camel.main.Main and use run() method:
From run javadoc:
Runs this process with the given arguments, and will wait until completed, or the JVM terminates.
Throws:
Exception
I have service which runs some init scripts after application startup (implemented with ApplicationListener<ApplicationReadyEvent>). In this scripts I need to call another services with RestTemplate which is #LoadBalanced. When the call to service is invoked there's no information about instances of remote service because discovery server was not contacted at that time (I guess).
java.lang.IllegalStateException: No instances available for api-service
at org.springframework.cloud.netflix.ribbon.RibbonLoadBalancerClient.execute(RibbonLoadBalancerClient.java:79)
So is there way how to get list of available services from discovery server at application startup, before my init script will execute?
Thanks
edit:
The problem is more related to fact, that in current environment (dev) all services are tied together in one service (api-service). So from within api-service I'm trying to call #LoadBalanced client api-service which doesn't know about self? Can I register some listener or something similar to know when api-service (self) will be available?
here are the sample applications. I'm mainly interested how to have working this method
edit2:
Now there could be the solution to create EurekaListener
public static class InitializerListener implements EurekaEventListener {
private EurekaClient eurekaClient;
private RestOperations restTemplate;
public InitializerListener(EurekaClient eurekaClient, RestOperations restTemplate) {
this.eurekaClient = eurekaClient;
this.restTemplate = restTemplate;
}
#Override
public void onEvent(EurekaEvent event) {
if (event instanceof StatusChangeEvent) {
if (((StatusChangeEvent) event).getStatus().equals(InstanceInfo.InstanceStatus.UP)) {
ResponseEntity<String> helloResponse = restTemplate.getForEntity("http://api-service/hello-controller/{name}", String.class, "my friend");
logger.debug("Response from controller is {}", helloResponse.getBody());
eurekaClient.unregisterEventListener(this);
}
}
}
}
and then register it like this:
EurekaEventListener initializerListener = new InitializerListener(discoveryClient, restTemplate);
discoveryClient.registerEventListener(initializerListener);
However this is only executed only when application is registered to discovery service first time. Next time when I stop the api-service and run it again, event is not published. Is there any other event which can I catch?
Currently, in Camden and earlier, applications are required to be registered in Eureka before they can query for other applications. Your call is likely too early in the registration lifecycle. There is an InstanceRegisteredEvent that may help. There are plans to work on this in the Dalston release train.
I am trying Ribbon configuration with RestTemplate based on bookmark service example but without luck, here is my code:
#SpringBootApplication
#RestController
#RibbonClient(name = "foo", configuration = SampleRibbonConfiguration.class)
public class BookmarkServiceApplication {
public static void main(String[] args) {
SpringApplication.run(BookmarkServiceApplication.class, args);
}
#Autowired
RestTemplate restTemplate;
#RequestMapping("/hello")
public String hello() {
String greeting = this.restTemplate.getForObject("http://foo/hello", String.class);
return String.format("%s, %s!", greeting);
}
}
with error page as below:
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Tue Mar 22 19:59:33 GMT+08:00 2016
There was an unexpected error (type=Internal Server Error, status=500).
No instances available for foo
but if I remove annotation #RibbonClient, everything will be just ok,
#RibbonClient(name = "foo", configuration = SampleRibbonConfiguration.class)
and here is SampleRibbonConfiguration implementation:
public class SampleRibbonConfiguration {
#Autowired
IClientConfig ribbonClientConfig;
#Bean
public IPing ribbonPing(IClientConfig config) {
return new PingUrl();
}
#Bean
public IRule ribbonRule(IClientConfig config) {
return new AvailabilityFilteringRule();
}
}
Is it because RibbonClient can not work with RestTemplate together?
and another question is that does Ribbon configuration like load balancing rule could be configured via application.yml configuration file?
as from Ribbon wiki, seems we can configure Ribbon parameters like NFLoadBalancerClassName, NFLoadBalancerRuleClassName etc in property file, does Spring Cloud also supports this?
I'm going to assume you're using Eureka for Service Discovery.
Your particular error:
No instances available for foo
can happen for a couple of reasons
1.) All services are down
All of the instances of your foo service could legitimately be DOWN.
Solution: Try visiting your Eureka Dashboard and ensure all the services are actually UP.
If you're running locally, the Eureka Dashboard is at http://localhost:8761/
2.) Waiting for heartbeats
When you very first register a service via Eureka, there's a period of time where the service is UP but not available. From the documentation
A service is not available for discovery by clients until the
instance, the server and the client all have the same metadata in
their local cache (so it could take 3 heartbeats)
Solution: Wait a good 30 seconds after starting your foo service before you try calling it via your client.
In your particular case I'm going to guess #2 is likely what's happening to you. You're probably starting the service and trying to call it immediately from the client.
When it doesn't work, you stop the client, make some changes and restart. By that time though, all of the heartbeats have completed and your service is now available.
For your second question. Look at the "Customizing the Ribbon Client using properties" section in the reference documentation. (link)