How can you configure the ObjectMapper used by AppEngine - google-app-engine

I have a AppEngine project that is served using Google Cloud EndPoints.
Some of the Request and Response objects (which I have no control over) have no attributes.
When those endpoints are invoked the call will fail with:
com.google.api.server.spi.handlers.EndpointsMethodHandler$RestHandler handle: exception occurred while invoking backend method
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No serializer found for class au.com.xandar.wylas.licence.endpoint.response.SendUserInviteResponse and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS)
Normally I would just get the ObjectMapper on instance startup and call
objectMapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
But I am struggling to work out how to get hold of the ObjectMapper that AppEngine is using.
And note:
I am not using Spring
I am not using Guice
I do not want to introduce either of these frameworks into the mix.
How can can I retrieve the ObjectMapper that AppEngine is using so that I can modify it's config?

Related

Spring Boot application gives "405 method not supported" exception for only Angular/HTML/JSP resources

I have an application written with Spring Boot and AngularJS. When I try to hit a REST service as part of this application, I am able to hit it with POST method wherever POST is configured for request mapping.
But if I try to request AngularJS bind pages, I get a "405 method not supported" exception. So I try to create HTML and JSP pages too, which are not bound to Angular but still, I am getting the same exception.
Where can I start debugging this, and what is the likely reason?
i am sharing here furthere details about issue.
Basically this existing application created/developed with Jhipster, angularjs, Spring boot and spring security does not allow to access html/angularjs related resources with POST from outside. I will explain here what different scenarios work and what is not not working. 1.Postman trying to access base url trying to fetch index.html from same application- Give 405 Post method not allowed.2.Created an independent Test.html in same application and trying to access it from postman- Gives 405 Post method not allowed.3.Created a service which allows POST access in same application- Able to hit service from WSO2 IS IDP and also from Postman.4.Created a separate application on tomcat and provided as callback in WSO2 IDP with starting point for SSO from base url of existing application- Able to hit callback URL on tomcat server. Firefox shows that a POST request was generated for callback URL from WSO2 IS IDP to tomcat based application 5.Created a separate application with Angular js and Spring boot and provided as callback in WSO2 IDP with starting point for SSO from base url of existing application- Able to hit callback URL on tomcat server. Firefox shows that a POST request was generated for callback URL from WSO2 IS IDP to new application with Spring boot and Angularjs. This took me down to conclusion that one of three is causing this issue
1. Spring security generated from JHipster
2. Angularjs
3. Some CORS or other filter from Spring Security is causing this issue.
Till now we have tried to different debugging methods like
1. disable CORS,
2. in angularjs-resource.js enable POST for get operation,
3. In SecurityCOnfigurer, try to permit POST method for base URL or resolve it to GET in httpsercurity authorizerequest etc.
4. Also ignoring resources in websecurity.
Application stack for existing application which we are trying to implement SSO is as below
1. Angularjs 1.5.8
2. Springboot 1.5.9.release
3. WSO2IS 5.4.1
4. WSO2AM 2.1.0
5. JHipster
Let me know if any particular area which we might have missed to analyze or different methods to try.
Thanks,
Sandeep
Try to disable CSRF in security config
#Configuration
public class SecurityConfig extends WebSecurityConfigurerAdapter {
...
#Override
protected void configure(HttpSecurity http) throws Exception {
http.csrf().disable();
...
}
...
}
#SpringBootApplication
#Import({
...
SecurityConfig.class
...
})
public class SpringBootApp {
...
}

How to generate OAuth2.0 Bearer when calling App Engine Endpoints API?

I am providing a REST API via App Engine. I used Cloud Endpoints to generate it, although the client will not be mobile Android/iPhone but rather a known web server. Since I am familiar with this server (it is part of my application), I decided to use Service Account authorization in order to authorize the API calls (In addition, I will do IP validation, but that's beside the point).
I made all the necessary arrangement, created a Google developer project, generated a service account id (and email), with a p12 file, and added all the annotations needed on the server side (including a User object in the implementing function).
Now I want to implement a call to this API, and in order for it to work, I need to include a proper authorization header in my request.
When working with Google APIs, the client libraries generate some Credential object which you later need to pass in building some Service object, which represents a Google API you wish to call. For example, if you want to access Drive API in Java, you will do:
Drive drive = new Drive.Builder(Globals.httpTransport, Globals.jsonFactory, credential).build();
Where credential object is the object I previously build as follows:
credential = new GoogleCredential.Builder().setTransport(Globals.httpTransport)
.setJsonFactory(Globals.jsonFactory)
.setServiceAccountId(serviceAccountEmail)
.setServiceAccountScopes(scopes)
.setServiceAccountUser(serviceAccountUser)
.setServiceAccountPrivateKeyFromP12File(file(serviceAccountPrivateKeyP12File))
.build();
However, in my case, the client is not calling a Google API, but rather my App Engine REST API. How do I go about generating (or using the credential object I created to obtain) a proper Authorization header?
You can find some documentation in the readme.html file that is generated alongside the bindings, and here.
You can get the following account information in the console, "Apis & Auth", "Credentials". Here you need to paste "Email Address" of the service account. Your #Api annotation should include the account's "Client Id" in the "clientIds" parameter.
String accountEmail = "your-service-account#developer.gserviceaccount.com";
String keyFilePath = "your-key-file.p12";
This is the minimum authorization scope that is required for Cloud Endpoints API. It only allows the app to access the user's e-mail address. Your #Api annotation should list it in the "scopes" parameter.
String emailScope = "https://www.googleapis.com/auth/userinfo.email";
Then you need to create some support objects and the credential. GsonFactory can be replaced with JsonFactory if you prefer.
HttpTransport httpTransport = GoogleNetHttpTransport.newTrustedTransport();
GsonFactory gsonFactory = new GsonFactory();
GoogleCredential credential = new GoogleCredential.Builder()
.setTransport(httpTransport)
.setJsonFactory(gsonFactory)
.setServiceAccountId(accountEmail)
.setServiceAccountScopes(Collections.singleton(emailScope))
.setServiceAccountPrivateKeyFromP12File(new File(keyFilePath))
.build();
And finally create your API client. Replace YourApi with the client from the generated bindings. If you want to test against the dev AppServer, you can call .setRootUrl(yourDevServerUrl + "/_ah/api") on the builder.
YourApi client = new YourApi.Builder(httpTransport, gsonFactory, credential)
.setApplicationName("YourClientName")
.build();

Is apache commons like HttpClient library equivalent supported in Apex Code on Salesforce's Force.com Platform?

I am trying to perform an external Http REST API callout using Apex Class from within my Salesforce Development Organization.
I was wondering if there is support for an equivalent HttpClient library like that of Apache Commons' HttpClient. Is there one?
From the documentation I realize that one way of doing it would be use the System.Http class to perform the request. Refer here for :Salesforce's System Classes and System.Http.
Example:
public class HttpCalloutSample {
// Pass in the endpoint to be used using the string url
public String getContent(String url) {
// Instantiate a new http object
Http h = new Http();
// Instantiate a new HTTP request, specify the method (GET) as well as the endpoint
HttpRequest req = new HttpRequest();
req.setEndpoint(url);
req.setMethod('GET');
// Send the request, and return a response
HttpResponse res = h.send(req);
return res.getBody();
}
}
The reason I am asking this question is because I remember running across a Apex Code Snippet from a tutorial that used such an API. I cant seem to find it now.
P.S: I understand the the Apex Code is a different language and Java libraries like the HttpClient do not run on the Salesforce platform. And there may not be direct language level way to integrate them both, unless there is a Apex Code binding to the library.
The System.HTTP class and friends is the only way to make HTTP requests from ApexCode. As you say apex is not java and you can't run random java libraries in apex.

How do I protect my API that was built using Google Cloud Endpoints?

The API is a backend to a mobile app. I don't need user authentication. I simply need a way to secure access to this API. Currently, my backend is exposed.
The documentation seems to only talk about user authentication and authorization, which is not what I need here. I just need to ensure only my mobile app can talk to this backend and no one else.
Yes, you can do that: use authentication to secure your endpoints without doing user authentication.
I have found that this way of doing it is not well documented, and I haven't actually done it myself, but I intend to so I paid attention when I saw it being discussed on some of the IO13 videos (I think that's where I saw it):
Here's my understanding of what's involved:
Create a Google API project (though this doesn't really involve their API's, other than authentication itself).
Create OATH client ID's that are tied to your app via its package name and the SHA1 fingerprint of the certificate that you will sign the app with.
You will add these client ID's to the list of acceptable ID's for your endpoints. You will add the User parameter to your endpoints, but it will be null since no user is specified.
#ApiMethod(
name = "sendInfo",
clientIds = { Config.WEB_CLIENT_ID, Config.MY_APP_CLIENT_ID, Config.MY_DEBUG_CLIENT_ID },
audiences = { Config.WEB_CLIENT_ID }
// Yes, you specify a 'web' ID even if this isn't a Web client.
)
public void sendInfo(User user, Info greeting) {
There is some decent documentation about the above, here:
https://developers.google.com/appengine/docs/java/endpoints/auth
Your client app will specify these client ID's when formulating the endpoint service call. All the OATH details will get taken care of behind the scenes on your client device such that your client ID's are translated into authentication tokens.
HttpTransport transport = AndroidHttp.newCompatibleTransport();
JsonFactory jsonFactory = new JacksonFactory();
GoogleAccountCredential credential = GoogleAccountCredential.usingAudience( ctx, Config.WEB_CLIENT_ID );
//credential.setSelectedAccountName( user ); // not specify a user
Myendpoint.Builder builder = new Myendpoint.Builder( transport, jsonFactory, credential );
This client code is just my best guess - sorry. If anyone else has a reference for exactly what the client code should look like then I too would be interested.
I'm sorry to say that Google doesn't provide a solution for your problem (which is my problem too).
You can use their API key mechanism (see https://developers.google.com/console/help/new/#usingkeys), but there is a huge hole in this strategy courtesy of Google's own API explorer (see https://developers.google.com/apis-explorer/#p/), which is a great development tool to test API's, but exposes all Cloud Endpoint API's, not just Google's services API's. This means anyone with the name of your project can browse and call your API at their leisure since the API explorer circumvents the API key security.
I found a workaround (based on bossylobster's great response to this post: Simple Access API (Developer Key) with Google Cloud Endpoint (Python) ), which is to pass a request field that is not part of the message request definition in your client API, and then read it in your API server. If you don't find the undocumented field, you raise an unauthorized exception. This will plug the hole created by the API explorer.
In iOS (which I'm using for my app), you add a property to each request class (the ones created by Google's API generator tool) like so:
#property (copy) NSString *hiddenProperty;
and set its value to a key that you choose. In your server code (python in my case) you check for its existence and barf if you don't see it or its not set to the value that your server and client will agree on:
mykey,keytype = request.get_unrecognized_field_info('hiddenProperty')
if mykey != 'my_supersecret_key':
raise endpoints.UnauthorizedException('No, you dont!')
Hope this puts you on the right track
The documentation is only for the client. What I need is documentation
on how to provide Service Account functionality on the server side.
This could mean a couple of different things, but I'd like to address what I think the question is asking. If you only want your service account to access your service, then you can just add the service account's clientId to your #Api/#ApiMethod annotations, build a GoogleCredential, and invoke your service as you normally would. Specifically...
In the google developer's console, create a new service account. This will create a .p12 file which is automatically downloaded. This is used by the client in the documentation you linked to. If you can't keep the .p12 secure, then this isn't much more secure than a password. I'm guessing that's why this isn't explicitly laid out in the Cloud Endpoints documentation.
You add the CLIENT ID displayed in the google developer's console to the clientIds in your #Api or #ApiMethod annotation
import com.google.appengine.api.users.User
#ApiMethod(name = "doIt", scopes = { Constants.EMAIL_SCOPE },
clientIds = { "12345678901-12acg1ez8lf51spfl06lznd1dsasdfj.apps.googleusercontent.com" })
public void doIt(User user){ //by convention, add User parameter to existing params
// if no client id is passed or the oauth2 token doesn't
// match your clientId then user will be null and the dev server
// will print a warning message like this:
// WARNING: getCurrentUser: clientId 1234654321.apps.googleusercontent.com not allowed
//..
}
You build a client the same way you would with the unsecured version, the only difference being you create a GoogleCredential object to pass to your service's MyService.Builder.
HttpTransport httpTransport = new NetHttpTransport(); // or build AndroidHttpClient on Android however you wish
JsonFactory jsonFactory = new JacksonFactory();
// assuming you put the .p12 for your service acccount
// (from the developer's console) on the classpath;
// when you deploy you'll have to figure out where you are really
// going to put this and load it in the appropriate manner
URL url = getClass().class.getResource("/YOURAPP-b12345677654.p12");
File p12file = new File(url.toURI());
GoogleCredential.Builder credentialBuilder = new GoogleCredential.Builder();
credentialBuilder.setTransport(httpTransport);
credentialBuilder.setJsonFactory(jsonFactory);
//NOTE: use service account EMAIL (not client id)
credentialBuilder.setServiceAccountId("12345678901-12acg1ez8lf51spfl06lznd1dsasdfj#developer.gserviceaccount.com"); credentialBuilder.setServiceAccountScopes(Collections.singleton("https://www.googleapis.com/auth/userinfo.email"));
credentialBuilder.setServiceAccountPrivateKeyFromP12File(p12file);
GoogleCredential credential = credentialBuilder.build();
Now invoke your generated client the same way
you would the unsecured version, except the builder takes
our google credential from above as the last argument
MyService.Builder builder = new MyService.Builder(httpTransport, jsonFactory, credential);
builder.setApplicationName("APP NAME");
builder.setRootUrl("http://localhost:8080/_ah/api");
final MyService service = builder.build();
// invoke service same as unsecured version

Cloud Endpoints HTTP Cookies

I am implementing Cloud Endpoints with a Python app that uses custom authentication (GAE Sessions) instead of Google Accounts. I need to authenticate the requests coming from the Javascript client, so I would like to have access to the cookie information.
Reading this other question leads me to believe that it is possible, but perhaps not documented. I'm not familiar with the Java side of App Engine, so I'm not quite sure how to translate that snippet into Python. Here is an example of one of my methods:
class EndpointsAPI(remote.Service):
#endpoints.method(Query_In, Donations_Out, path='get/donations',
http_method='GET', name='get.donations')
def get_donations(self, req):
#Authenticate request via cookie
where Query_In and Donations_Out are both ProtoRPC messages (messages.Message). The parameter req in the function is just an instance of Query_In and I didn't find any properties related to HTTP data, however I could be wrong.
First, I would encourage you to try to use OAuth 2.0 from your client as is done in the Tic Tac Toe sample.
Cookies are sent to the server in the Cookie Header and these values are typically set in the WSGI environment with the keys 'HTTP_...' where ... corresponds to the header name:
http = {key: value for key, value in os.environ.iteritems()
if key.lower().startswith('http')}
For cookies, os.getenv('HTTP_COOKIE') will give you the header value you seek. Unfortunately, this doesn't get passed along through Google's API Infrastructure by default.
UPDATE: This has been enabled for Python applications as of version 1.8.0. To send cookies through, specify the following:
from google.appengine.ext.endpoints import api_config
AUTH_CONFIG = api_config.ApiAuth(allow_cookie_auth=True)
#endpoints.api(name='myapi', version='v1', auth=AUTH_CONFIG, ...)
class MyApi(remote.service):
...
This is a (not necessarily comprehensive list) of headers that make it through:
HTTP_AUTHORIZATION
HTTP_REFERER
HTTP_X_APPENGINE_COUNTRY
HTTP_X_APPENGINE_CITYLATLONG
HTTP_ORIGIN
HTTP_ACCEPT_CHARSET
HTTP_ORIGINALMETHOD
HTTP_X_APPENGINE_REGION
HTTP_X_ORIGIN
HTTP_X_REFERER
HTTP_X_JAVASCRIPT_USER_AGENT
HTTP_METHOD
HTTP_HOST
HTTP_CONTENT_TYPE
HTTP_CONTENT_LENGTH
HTTP_X_APPENGINE_PEER
HTTP_ACCEPT
HTTP_USER_AGENT
HTTP_X_APPENGINE_CITY
HTTP_X_CLIENTDETAILS
HTTP_ACCEPT_LANGUAGE
For the Java people who land here. You need to add the following annotation in order to use cookies in endpoints:
#Api(auth = #ApiAuth(allowCookieAuth = AnnotationBoolean.TRUE))
source
(Without that it will work on the local dev server but not on the real GAE instance.)

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