Das kannste schon so machen

Das kannste schon so
machen…
André Goliath

Disclaimer:
This talk is bad
Because I had no time
Because of the issues this talk is about

Spring Boot & Netflix OSS Stack
WebServiceTemplate & Proxies
Jenkins & NPM

You all know I´m a nice, calm, relaxed,
chilled, error-forgiving guy, right?

@ControllerAdvice
public class GlobalControllerExceptionHandler extends ResponseEntityExceptionHandler {
…
@ExceptionHandler({Exception.class})
private ResponseEntity<Object> handleAllUnknownExceptions(Exception ex) {
return handleExceptionInternal(ex, null, null,
HttpStatus.INTERNAL_SERVER_ERROR, null);
}
@Override
@ResponseBody
protected ResponseEntity<Object> handleExceptionInternal(Exception ex, Object body,
HttpHeaders headers, HttpStatus status, WebRequest request) {
BaseResponse errorMessage = createErrorMessage(ex);
HttpStatus returnStatus = status != null ? status :
HttpStatus.INTERNAL_SERVER_ERROR;
ResponseStatus exResponseStatus = AnnotationUtils.findAnnotation(ex.getClass(),
ResponseStatus.class);
if (exResponseStatus != null) {
returnStatus = exResponseStatus.value();
}
return new ResponseEntity<>(errorMessage, headers, returnStatus);
}
}

@Configuration
@EnableWebMvc
public class DispatcherServletConfigurer{
@Bean
public FSLDispatcherServletHandlerErrorConfigurator getDispatcherServletPostProcessor(){
return new FSLDispatcherServletHandlerErrorConfigurator();
}
public class FSLDispatcherServletHandlerErrorConfigurator implements BeanPostProcessor {
public Object postProcessBeforeInitialization(Object bean, String beanName) throws …{
if (bean instanceof DispatcherServlet) {
DispatcherServlet disp = ((DispatcherServlet) bean);
disp.setThrowExceptionIfNoHandlerFound(true);
}
return bean;
}
…
}

That´s so Spring Boot 1.2.x!
(1.2 was released in Dec 2014, 1.3 in Nov 2015)

spring.mvc.throw-exception-if-no-handler-found=true
spring.resources.add-mappings=false
(you still need the @ControllerAdvice though)

Configserver Spring Cloud Config
Service Registry eureka
Reverse Proxy zuul
Circuit Breaker hystrix

Client
Reverse Proxy
(ZUUL)
Service Registry
(EUREKA)
Config Server

So how do you deliver the configuration
for all your microservices and
environments?

What is that zuul anyway?
And what does it do?
AND HOW DO WE USE IT?

@SpringBootApplication
@Controller
@EnableZuulProxy
public class ZuulApplication {
public static void main(String[] args) {
new SpringApplicationBuilder(ZuulApplication.class)
.web(true).run(args);
}
}

ZUUL DOES MUCH MORE
THINGS THEN WE SEE!

NOTE TO SELF:
SPRING DOES NOT USE SEMANTIC
VERSIONING!

Lessons learned
from working with Spring

… AND ESPECIALLY
THE RELEASE NOTES!

private WebServiceTemplate attachProxy(WebServiceTemplate template) {
if (config.getUseProxy()) {
template.setProxy(new HttpHost(config.getProxyHost(),
config.getProxyPort()))
}
return template;
}
}

if (senderForProxy == null) {
HttpClient client = HttpClients.custom()
.setProxy(new HttpHost(config.getProxyHost(),
.build();
senderForProxy = new HttpComponentsMessageSender(client);
}
template.setMessageSender(senderForProxy);
}
return template;
}
}

org.springframework.ws.client.WebServiceIOException:
I/O error: null;
nested exception is org.apache.http.client
.ClientProtocolException
at org.springframework.ws.client.core.WebServiceTemplate
.sendAndReceive(WebServiceTemplate.java:543)
...
Caused by: org.apache.http.client.ClientProtocolException
at org.apache.http.impl.client.AbstractHttpClient.execute
(AbstractHttpClient.java:909)
... 32 more
Caused by: org.apache.http.ProtocolException:
Content-Length header already present
... 39 more

.addInterceptorFirst(
new HttpComponentsMessageSender
.RemoveSoapHeadersInterceptor()
)
.build();
}
}
return template;
}
}

SSL Protocol Error: Handshake failure

.useSystemProperties()
)
.build();
}
}
return template;
}
}

400
(a.k.a. „Bad Request“)

400
(a.k.a. least helpful HTTP
response code of all times.)

…5 Hours of HTTP traffic
comparison later…
SOAP-Namespaces?
Am I missing any HTTP header?
Malformed XML?
No Proxy allowed?
Still SSL issues?

…5 Hours of HTTP traffic
comparison later…

I am sending one header too much.

.useSystemProperties()
)
.build();
senderForProxy.setAcceptGzipEncoding(false);
}
}
return template;
}
}

It took me about 5 full days
to get this right.

Lessons learned
from the proxy disaster

Have the same
communication infrastructure
on every(!) test setup

No Proxy? Make your own.
var http = require('http'),
httpProxy = require('http-proxy');
var proxy = httpProxy.createProxyServer({});
var interceptingServer = http.createServer(function (req, res) {
// define your custom logic to handle the request
// and then proxy the request.
proxy.web(req, res, {target: 'http://MyActualTargetService.com'});
});
console.log("proxy listening on port 5050")
interceptingServer.listen(5050);
https://github.com/nodejitsu/node-http-proxy

Node Package Manager v2
is bad. Like, really bad.

npm install
…on Senacor Hardware: 15 min
…on Clients Dev. Machine: 20 min
…on Jenkins: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Filesystem Size Used Avail Use% Mounted on
...
/dev/mapper/datavg-lv_optsoftware
492G 22G 446G 5% /opt/software

...
Filesystem Inodes IUsed IFree IUse% Mounted on
...
32768000 32428987 39013 99% /opt/software

...
Filesystem Inodes IUsed IFree IUse% Mounted on
...
32768000 32428987 39013 99% /opt/software
I lost track when the deepest node_modules path
was about 2000 chars long…

npm dedupe would help,
but only if npm install worked
at least once…

Beware:
Npm3 will be the default package
manager starting with nodejs 5.x,
and is a breaking change:

Lessons learned:
We started the project when
NodeJS 4.x and npm 3.x
were still unstable.
That time is gone. Go for it.

Thank You!
André Goliath
Senior Technical Consultant
andre.goliath@senacor.de

Das kannste schon so machen

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