Alternatives to JSON file credentials? - google-cloud-storage

My Java backend server has to upload files to the Google Cloud Storage (GCS).
Right now I just run
public void store(MultipartFile multipartFile) throws IOException {
Storage storage = StorageOptions.getDefaultInstance().getService();
storage.create(
BlobInfo.newBuilder(
BUCKET_NAME,
Objects.requireNonNull(multipartFile.getOriginalFilename()))
.build(),
multipartFile.getBytes()
);
}
Having set GOOGLE_APPLICATION_CREDENTIALS=$PROJECT_DIR$/project-1234-abcdefg.json in my environment.
However, this makes things complicated for my deployment setup. I don't know how I would go about making this file available to my service.
Is there another way to get access to GCS for my service account?
Background
I am deploying my server to Heroku as a compiled jar file and I don't know how to make the credentials available to my server during deployment.

You need a Google Account to access to GCS, either personal or technical. Technical is a service account.
However, you have another solution, but not really easy to implement. I wrote an article for securing serverless product with Cloud Endpoint with and API Key. Here your serverless solution can be Cloud Storage. But that implies that you call GCS with REST API and not with the java library, not very fun. That also implies additional cost for the hosting and the processing time of Cloud Endpoint.
Note: you can improve the authorization from API Key to Firebase auth or something else if you prefer. Check the Cloud Endpoint authentication capabilities
Note2: Google is working on another authentication mechanism but I don't know at which stage are the developments, and if it's plan for 2020. In any case, your constraint is known and addressed by Google

Related

How to setup google service account authorization in Node.js with JSON key file?

Trying to make use of the Server to Server OAuth flow defined here:
https://developers.google.com/identity/protocols/OAuth2ServiceAccount
Since I'm running from a local dev environment, I've created a service account in GCP and downloaded the JSON file with the private key, but cannot find any Node.js code examples on how to:
1) load the json file
2) set delegated credentials (for G Suite domain-wide authorization)
Places I've looked (besides stackoverflow) are Google's git wiki for the node.js client library, which does talk about server to server auth, but seems to assume you're running from appengine or google cloud and don't need to load a key file:
https://github.com/googleapis/google-api-nodejs-client#service-to-service-authentication
The Admin SDK Activities Reports API has a Node example, but it's using the web-based flow assuming a user is present:
https://developers.google.com/admin-sdk/reports/v1/quickstart/nodejs
Buried deep in the Node.js samples is use of the Directory API, which does seem to take a keyfile as input, but when I try running locally it says getClient is not a constructor, and still this example doesn't show how to set the G Suite admin user for context (which is generally when a refresh token and access token are loaded into the app):
https://github.com/googleapis/google-api-nodejs-client/blob/master/samples/directory_v1/group-delete.js
So... does anybody have an example of this? I really don't want to switch to a Python runtime but Google seems to have left out important examples on this topic.

Use only a domain and disable https://storage.googleapis.com url access

I am newbie at cloud servers and I've opened a google cloud storage to host image files. I've verified my domain and configured it, to view images via my domain. The problem is, same file is both accessible via my domain example.com/images/tiny.png and also via storage.googleapis.com/example.com/images/tiny.png Is there any solution to disable access via storage.googleapis.com and use only my domain?
Google Cloud Platform Support Version:
NOTE: This is the reply from Google Cloud Platform Support when contacted via email...
I understand that you have set up a domain name for one of your Cloud Storage buckets and you want to make sure only URLs starting with your domain name have access to this bucket.
I am afraid that this is not possible because of how Cloud Storage permission works.
Making a Cloud Storage bucket publicly readable also gives each of its files a public link. And currently this public link can’t be disabled.
A workaround would be implement a proxy program and running it on a Compute Engine virtual machine. This VM will need a static external IP so that you can map your domain to it. The proxy program will be in charged of returning the requested file from a predefined Cloud Storage bucket while the bucket keeps to be inaccessible to the public.
You may find these documents helpful if you are interested in this workaround:
1. Quick start to set up a Linux VM (1).
2. Python API for accessing Cloud Storage files (2).
3. How to download service account keys to grant a program access to a set of services (3).
4. Pricing calculator for getting a picture on how much a VM may cost (4).
(1) https://cloud.google.com/compute/docs/quickstart-linux
(2) https://pypi.org/project/google-cloud-storage/
(3) https://cloud.google.com/iam/docs/creating-managing-service-account-keys
(4) https://cloud.google.com/products/calculator/
My Version:
It seems the solution to this question is really a simple, just FUSE Google Cloud Storage with VM Instance.
After FUSE private files from GCS can be accessed through VM's IP address. It made Google Cloud Storage Bucket act like a directory.
The detailed documentation about how to setup FUSE in Google Cloud is here.
There is but it requires you to do more work.
Your current solution works because you've made access to the GCS bucket (example.com), public and then you're DNS aliasing from your domain.
An alternative approach would be for you to limit access to the GCS bucket to one (possibly several) accounts and then run a web-server that uses one of the accounts to access your image files. You could then also either permit access to your web-server to anyone or also limit access to it.
More work for you (and possibly cost) but more control.

Retrieve logged user information from cloud foundry web application

We developed a web application using SAP Web-IDE Full Stack; we need to retrieve the details of the user logged into application (as defined in SAP Cloud Platform Identity Authentication Administration), for example display name and assigned groups.
We tried the userapi/currentUser API, but it seems to work only on NEO environment, for this reason is working fine while debugging in Web-IDE, but we get a 404 error when deploying the app on Cloud Foundry.
Do we need to add a new destination to make userapi work also on CF? Or is there some kind of similar solution available on Cloud Foundry?
I highly suggest using the SAP S/4HANA Cloud SDK for such tasks. It is an SDK developed to make building applications for SAP Cloud Platform easy, by providing easy to use mechanisms for all the Cloud Platform mechanisms.
Regarding your task at hand, there is a UserAccessor class that you can use like this:
final Optional<User> user = UserAccessor.getCurrentUser();
This works on Neo as well as on Cloud Foundry, i.e. there is a single interface for both platforms, which allows you to develop your app in a platform agnostic way.
If this sounds like it could solve your problem, I recommend checking out this blog post series to get started.
Alternatively, you can also simply add the following dependency to your project to start testing the SDK:
<dependency>
<groupId>com.sap.cloud.s4hana.cloudplatform</groupId>
<artifactId>scp-neo</artifactId>
<version>2.7.0</version>
</dependency>
For Cloud Foundry use scp-cf instead of scp-neo.
Hope this helps!
P.S.: To answer your question also on a technical level, Cloud Foundry uses so-called JWTs for authentication and authorization. You can check whether a JWT is present by looking at the Authorization header of the request. The JWT should hold the information you're looking for.
In SAP Cloud Foundry if you develop a MTA using XSUAA service to manage User Authentication and Admistration, defined for example in the mta.yaml,
...
resources:
- name: uaa_myapp
parameters:
path: ./xs-security.json
service-plan: application
service: xsuaa
type: org.cloudfoundry.managed-service
...
you can use the UAA API published from XSUAA service self to manage user authentication and authorization (e.g.: retrieve user info, groups assigned, password management etc..). also in the case the application is federated with another IDP.
To consume this API for example to retrieve user info you need to:
Determine the XSUAA endpoint bound to your app (SCP Cockpit > XSUAA service detail > take the value url)
Create a destination (xsuaa_api_destination) of type OAuth2TokenExchange bound to your app with url url took before, and fill OAuth2 authentication parameters with the data contained in XSUAA service detail (step 1).
From your app execute the call xsuaa_api_destination/userinfo, for example using an ajax if you are using JS.
You can find other info in Account and Authentication Service of the Cloud Foundry Environment SAP doc.

Google Cloud Storage 500 Internal Server Error 'Google::Cloud::Storage::SignedUrlUnavailable'

Trying to get Google Cloud Storage working on my app. I successfully saved an image to a bucket, but when trying to retrieve the image, I receive this error:
GCS Storage (615.3ms) Generated URL for file at key: 9A95rZATRKNpGbMNDbu7RqJx ()
Completed 500 Internal Server Error in 618ms (ActiveRecord: 0.2ms)
Google::Cloud::Storage::SignedUrlUnavailable (Google::Cloud::Storage::SignedUrlUnavailable):
Any idea of what's going on? I can't find an explanation for this error in their documentation.
To provide some explanation here...
Google App Engine (as well as Google Compute Engine, Kubernetes Engine, and Cloud Run) provides "ambient" credentials associated with the VM or instance being run, but only in the form of OAuth tokens. For most API calls, this is sufficient and convenient.
However, there are a small number of exceptions, and Google Cloud Storage is one of them. Recent Storage clients (including the google-cloud-storage gem) may require a full service account key to support certain calls that involve signed URLs. This full key is not provided automatically by App Engine (or other hosting environments). You need to provide one yourself. So as a previous answer indicated, if you're using Cloud Storage, you may not be able to depend on the "ambient" credentials. Instead, you should create a service account, download a service account key, and make it available to your app (for example, via the ActiveStorage configs, or by setting the GOOGLE_APPLICATION_CREDENTIALS environment variable).
I was able to figure this out. I had been following Rail's guide on Active Storage with Google Storage Cloud, and was unclear on how to generate my credentials file.
google:
service: GCS
credentials: <%= Rails.root.join("path/to/keyfile.json") %>
project: ""
bucket: ""
Initially, I thought I didn't need a keyfile due to this sentence in Google's Cloud Storage authentication documentation:
If you're running your application on Google App Engine or Google
Compute Engine, the environment already provides a service account's
authentication information, so no further setup is required.
(I am using Google App Engine)
So I commented out the credentials line and started testing. Strangely, I was able to write to Google Cloud Storage without issue. However, when retrieving the image I would receive the 500 server error Google::Cloud::Storage::SignedUrlUnavailable.
I fixed this by generating my private key and adding it to my rails app.
Another possible solution as of google-cloud-storage gem version 1.27 in August 2020 is documented here. My Google::Auth.get_application_default as in the documentation returned an empty object, but using Google::Cloud::Storage::Credentials.default.client instead worked.
If you get Google::Apis::ClientError: badRequest: Request contains an invalid argument response when signing check that you have dash in the project name in the signing URL (i.e projects/-/serviceAccounts explicit project name in the path is deprecated and no longer valid) and that you have "issuer" string correct, as the full email address identifier of the service account not just the service account name.
If you get Google::Apis::ClientError: forbidden: The caller does not have permission verify the roles your Service Account have:
gcloud projects get-iam-policy <project-name>
--filter="bindings.members:<sa_name>"
--flatten="bindings[].members" --format='table(bindings.role)'
=> ROLE
roles/iam.serviceAccountTokenCreator
roles/storage.admin
serviceAccountTokenCreator is required to call the signBlob service, and you need storage.admin to have ownership of the thing you need to sign. I think these are project global rights, I couldn't get it to work with more fine grained permissions unfortunately (i.e one app is admin for a certain Storage bucket)

Access to audit events of UAA (User Account and authentication) events in Swisscom cloud

Is it possible to get access to events generated by User Account and Authentication (UAA) server in the context of Swisscom Application Cloud?
It is essential for me, to be able to have an audit trail of actions executed by authorised operators through the API (that would include cli and portal).
What I am looking for is an alternative of AWS CloudTrail for IAM module, that you can turn on for specific VPCs / regions there.
I have found this in the CF documentation (https://docs.cloudfoundry.org/loggregator/cc-uaa-logging.html) but that (as far as I understand it) requires infrastructure level access.
Thanks a lot for any hints.
We can't expose UAA logs to individual customers since it contains probably sensitive information about other users or the platform.
You should be able to retrieve the logs of your application in the application logs (which you can send to a syslog drain, i.e. the ELK/Elasticsearch service).
All API interactions should be covered by this log stream, according to the documentation:
Users make API calls to request changes in app state. Cloud Controller, the Cloud Foundry component responsible for the API, logs the actions that Cloud Controller takes in response.
For example:
2016-06-14T14:10:05.36-0700 [API/0] OUT Updated app with guid cdabc600-0b73-48e1-b7d2-26af2c63f933 ({"name"=>"spring-music", "instances"=>1, "memory"=>512, "environment_json"=>"PRIVATE DATA HIDDEN"})
From https://docs.cloudfoundry.org/devguide/deploy-apps/streaming-logs.html