(Background: I am new to Google App Engine, familiar with other cloud providers' services)
I am looking for access/view similar to shell access to production node.
With a Python/Django based Google App Engine App, I would like to view the code in production.
One view I could find is the StackDriver 'Debug' view.
However, apparently the code shown in the Debug view doesn't reflect the updated production code (based on what is showing on the production site, for example, the text on the home page different).
Does Google App Engine allow me to ssh into the VM where the application/code is running?
If not, how can check the code that's running in production?
Thanks.
According to the SSH debugging row in the Comparing environments table SSH access is supported for flex environment apps but not for standard environment apps.
From Connecting to the instance:
If a VM instance is in debug mode, you can connect to its host by
using SSH in the console or with gcloud.
To connect to an instance in the console:
Visit the Cloud Platform Console instances page for your project:
Go to the instances page
Click SSH in the far right of the row containing the instance you want to access:
This puts the instance into debug mode, and opens an SSH session for the instance in a terminal window.
You can also select different options to start an SSH session from the drop-down list.
At this point you are in the instance host, which has several containers running in it. See Understanding common
containers next for more information about these.
In the terminal window, list the containers running in the instance:
sudo docker ps
The output of the sudo docker ps command lists each container by row; locate the row that contains your project ID: this is the
container running your code. Note the NAME of this container.
Optionally, list logging information for your application by invoking:
sudo docker logs [CONTAINER-NAME]
Start a shell in the container that is running your code:
container_exec [CONTAINER-NAME] /bin/bash
When finished debugging, enter exit to exit the container, then exit again to exit the SSH session.
Disable debugging for your instance to allow it to resume normal operation.
If you are using the standard environment, the answer is no, you can't really inspect or see the code directly. You've mentioned looking at it via Stackdriver Debugger, which is one way to see a representation of it.
It sounds like if you have a reason to be looking at the code, then someone in your organization should grant you the appropriate level of access to your source code management system. I'd imagine if you're deployment practices are mature, then they'd likely branch the code to map to your deployed versions and you could inspect in detail locally.
Related
Our Google Appengine flex app has configured HeapDumpOnOutOfMemoryError.. we did have a few crashes due to OOM. But where can we find the heap dump?
Right now, in App Engine, there isn't a way to track heap dump logs directly using Stackdriver - the tool used for logging in App Engine. The developers at Google are aweare of it and you can track the Feature Request for this functionality here.
In alternative to that, you can try one thing. As indicated in this other similar case here, you can enable the debug mode in your instance and then, connect to it via SSH. Once you connect via SSH, you need to run the following commands.
sudo docker ps - to list the containers of your instance and find the one related to your project ID;
sudo docker logs [CONTAINER-NAME] - with the name got from the last command, get the logs here;
Or start a shell to check it further with sudo docker exec -it [CONTAINER-NAME] /bin/bash
All these steps are further explained and with more information in the official documentation: Debugging an instance
Let me know if the information helped you!
Apologies for the seemingly obvious question, but I figure the answer might help others. I can't for the life of me find documentation on the filepath within the Google App Engine VM (Cloud Shell) where I can find the static files being served from. I need to pull the latest upstream changes from a private github repo.
Note that I navigated elsewhere in the VM and even restarting the session didn't put me in a default project root path within the VM as I expected it to.
There are several issues to address here:
The Cloud Shell is a virtual shell
Google Cloud Shell is an interactive shell environment for Google
Cloud Platform.
The environment where you're working is a container running in a VM in a Google-owned project inside GCP.
You can verify this by checking the metadata server (only available for GCP VMs):
curl -H 'Metadata-Flavor:Google' "http://metadata.google.internal/computeMetadata/v1/?recursive=true&alt=text"
In the metadata provided you'll see how this container is created and configured.
The Cloud Shell is tied to the user, so you'll always access the same environment if you access it with the same credentials, no matter the project. However, if you access with a different user, you'll get a different environment.
You can't access GAE standard instances
GAE is a fully managed environment, and you won't be able to access it. In this way, you won't be able to find the root of the running app engine project.
However, by the way GAE deploys your code, it uses a staging bucket to gather the code before compiling. You can find your staging bucket through the App Engine Admin API. This is usually staging.<PROJECT_ID>.appspot.com, although you can change this configuration. You can get your files from there.
You can access GAE flex apps
However, the deployment in flex gets your files, build a Docker container with them, and then deploys this container inside a VM.
As per the docs, you can connect directly to your container by running:
gcloud app instances ssh [INSTANCE-NAME] --service [SERVICE] --version [VERSION]
docker exec -it gaeapp /bin/bash
Regarding your issue
According what you say in the comments of the question, your issue could come from a myriad of places. From changing the shell you're connecting to, to resetting your shell environment (deleting all the files), to a thousand different possible problems.
The best way to think about it is regard the Cloud Shell as a temporal environment to run commands, but not as a virtual machine.
Knowing that, you could mount a persistent filesystem (GCS through GCSFuse, Cloud Filestore, ...) to persist your work, or simply use Git to have your work always synced on a repo.
GAE Flex has some nice CI integrations, so that's a plus for going the Git route.
I would like to debug my Google App Engine (GAE) app locally but without using localhost. Since my application is made up of microservices, the urls in a production environment would be along the lines of:
https://my-service.myapp.appspot.com/
But code in one service can call another service and that means that the urls are hardcoded. I could of course use a mechanism in code to determine whether the app is running locally or on GAE and use urls that are different although I don't see how a local url would handle the since the only way to run an app locally is to use localhost. Hence:
http://localhost:8080/some-service
Notice that "some-service" maps to a servlet, whereas "my-service" is a name assigned to a service when the app is uploaded. These are really two different things.
The only possible solution I was able to find was to use a reverse proxy which would map one url to a different one. Still, it isn't clear whether the GAE development SDK even supports this.
Personally I chose to detect the local development vs GAE environment and build my inter-services URLs accordingly. I feel it was a well-worthy effort, I've been (re)using it a lot. No reverse proxy or any other additional ops necessary, it just works.
Granted, I'm using Python, so I'm not 100% sure a complete similar Java solution exists. But maybe it can point you in the right direction.
To build the per-service URLs I used modules.get_hostname() (the implementation is presented in Resolve Discovery path on App Engine Module). I believe the Java equivalent would be getInstanceHostname() from com.google.appengine.api.modules.
This method, when executed on the local server, automatically provides the particular port the server listens to for each service.
BTW, all my services for an app are executed by a single development server process, which listens on multiple ports (this is, I guess, how it can provide the modules.get_hostname() info). See Running multiple services using dev_appserver.py on different ports. This is part I'm unsure about: if/how the java local dev server can simultaneously run multiple services. Apparently this used to be supported some time ago (when services were still called modules):
Serving multiple GAE modules from one development server?
GAE modules on development server
This can be accomplished with the following steps:
Create an entry in the hosts file
Run the App Engine Dev server from a Terminal using certain options
Use IntelliJ with Remote debugging to attach the App Engine Dev server.
To edit the hosts file on a Mac, edit the file /etc/hosts and supply the domain that corresponds to your service:. Example:
127.0.0.1 my-service.myapp.com
After you save this, you need to restart your computer for the changes to take place.
Run the App Engine Dev server manually:
dev_appserver.sh --address=0.0.0.0 --jvm_flag=-Xdebug
--jvm_flag=-Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8000
[path_to_exploded_war_directory]
In IntelliJ, create a debug configuration. Use the Remote template to create this configuration. Set the host to the url you set in the hosts file and set the port to 8000.
You can set a breakpoint and run the app in IntelliJ. IntelliJ will attach to the running instance of App Engine Dev server.
Because you are using a port during debugging and no port is actually used when the app is uploaded to the GAE during production, you need to add code that identifies when the app is running locally and when it's running on GAE. This can be done as follows:
private String mServiceUrl = "my-service.my-app.appspot.com";
...
if (SystemProperty.environment.value() != SystemProperty.Environment.Value.Production) {
mServiceUrl += ":8000";
}
See https://cloud.google.com/appengine/docs/standard/java/tools/using-local-server
An improved solution is to avoid including the port altogether and not having to use code to determine whether your app is running locally or on the production server. One way to do this is to use Charles (an application for monitoring and interacting with requests) and use a feature called Remote Mapping which lets you map one url to another. When enabled, you could map something like:
https://my-service.my-app.appspot.com/
to
https://localhost:8080
You would then enable the option to include the original host, so that this gets delivered to the local dev server. As far as your code is concerned it only sees:
https://my-service.my-app.appspot.com/
although the ip address will be 127.0.0.1:8080 when remote mapping is enabled. To use https on local host however does require that you enable ssl certificates for Charles.
For a complete overview on how to setup and debug microservices for a GAE Java app in IntelliJ, see:
https://github.com/JohannBlake/gae-microservices
I have a website that is currently running under GAE... unfortunately, I, nor anyone on the team, does not have access the local environment that it was created from.... Is it possible to create a local environment or at least get a copy of the application files and database from an existing GAE installation?
What you need is the application source code, not the "local environment".
Ideally this source code would be on a version control system (ie GIT,SVN), Google cloud platform provides free GIT repositories for your projects so you might try looking there first. There's also a tool for both Java and python that allow you to download the source of a deployed version, provided you are authenticated as either the dev who uploaded it or a project owner. EDIT: as stated by Dan Cornilescu this feature can be disabled.
As for the database info there's plenty of tools available to "export" your GAE datastore info, just consider for your project that it might be easier to do the queries manually than actually implementing this tools.
Thanks for help... But unfortunately, this code is not in GIT. Furthermore,
being new to Google hosting, I wasn't clear on my setup... My web instance is actually running within Compute Engine not Application Engine. Be that as it may, with some additional search, I was first able to find out how to browse my filesystem by accessing the VM Instances menu option under the Compute Engine section of the Google Cloud Platform interface. On the VM Instances page, it will show your instance and an option to the left side of the instance to connect with a drop down box that will allow you to open a browser window that shows the instance's file system. In addition to this, I found this link https://www.youtube.com/watch?v=9ssfE6ODpak that shows how to configure Filezila FTP client to access your server instance - very helpful. From there, I was able to download all of my site files from the var/www directory. Now, onto extracting my data... Thanks again!
I am trying to follow the instructions for running a simple new Google App Engine web application locally (without Google Web Toolkit, just the Web App) named "tunes".
I am following these instructions. Step one is to make a run configuration. I made one using all the defaults; I checked that under the Server tab the "Run built-in Server" box is checked. However, when I Run the app, I get the Console; right below the console tab it says
<terminated> tunes [Web Application] C:\Program Files (x86)\Java\jre7\bin\javaw.exe (Feb 26, 2014, 5:35:44 PM)
then below the line is what looks like a classic Unix "Usage" error message in the console, in red type, whose first line is
Usage: <dev-appserver> [options] <app directory>
followed by a list of options, and then nothing else happens that I can see.
I tried pointing a browser at http://localhost:8888/tunes as suggested by the documentation, but Firefox could not find a server active at that port.
Under the Arguments tab in the Run Configuration is the following:
"-codeServerPort 9997 --port=8888 org.tunes.gaeproject.Tunes C:\Users\cdf\java\eclipse4.3.1workspace\tunes\war"
I can successfully deploy the web application to the Google App Engine site and run it there.
What do I have misconfigured?
Google AppEngine application is not meant to run on local server, and neither you could create its docker image etc to deploy it anywhere you wish.
Instead I suggest you to port your application to Google Compute Engine (GCE) first within your deployment setup, which might require minor code refactorings, and Kubernetes kinda auto-scaling deployment will functional equivalent to what you have now. But with approach you may port the application easily to local server setup, or a docker image to run from any virtualization environment