Config for using psycopg2 to access to Cloud SQL instance - python

I am using a PostgreSQL in Cloud SQL along with psycopg2 library to connect to database from my python code. The current one that I have is associated with a VPC network in which my google compute engines also in that VPC. So, in this case, my config to connect to this cloud sql instance can use private ip and my config look like this:
config['db-cloudsql'] = {
"host" : "10.x.x.x" # cloud sql private ip address
"user" : "postgres"
"password" :"xxxxx"
"database" : "postgres"
}
But now I have another vm instance from another VPC network that need to access to this cloud sql instance. I know that I can access to the cloud sql instance using public ip. (by adding my vm to authorised network) But this vm need to access to the cloud sql instance very often. So I am not sure that the cost from accessing with public ip will be higher compared with accessing with private ip (cannot find any related document about this). I tried peering 2 vpc networks for accessing with private ip but just found that I cannot use this method to connect to sql with private ip from this document
I have found from the document that I can use instance connection name as a host for my config so it should be something like:
config['db-cloudsql'] = {
"host" : "project-name:asia-southeast1:mydbname" #instance connection name
"user" : "postgres"
"password" :"xxxxx"
"database" : "postgres"
}
I haven't try this method yet, it might not working but if it somehow works, how will it differ from using public ip addess in term of cost?
Thank you

It seems like your question boils down into two parts:
Are there any alternatives to public IP or private IP?
No. You have to use one or the other to connect to your Cloud SQL instance. Private IP allows access from a VPC, Public IP is used pretty much everywhere else.
Cost of public IP vs private IP
You can find a breakdown of the costs here. In short, there is not really any extra charges with a Public IP. You do have to pay $.01 per hour while the instance is idle (to reserve the public IP address), and just like private IPs, you are responsible for costs of the Network Egress between regions.
I can use instance connection name as a host for my config
This is incorrect. If you are using the Cloud SQL Proxy to connect, it can create a Unix domain socket (at /cloudsql/INSTANCE_CONNECTION_NAME) that can be used to connect to your instance. However the proxy only authenticates your connection - it still needs a valid connection path (Public vs Private).

As you can see in this PostgreSQL pricing documentation there is no difference in the pricing as you use the public IP or the connection name on the Cloud SQL side. If you want to keep the cost as low as possible you can try to keep your Compute Engine instances in the same region, or at least in the same continent as your Cloud SQL instance.

Related

sshtunnel forwarding and mysql connection on google cloud function

I am trying to connect to a MySQL server through ssh tunnel on one of my google cloud functions. This works fine in my home environment. I assume it is some port issue on cloud function.
Edit: For clarification the MySQL server sits on a Namecheap shared hosting web server. Not Google Cloud SQL
Every time I run this I timeout with "unknown error". The tunnel appears to be successful. I am however unable to get the mysql connection to work.
import base64
import sshtunnel
import mysql.connector
def testing(event, context):
"""
Testing function
"""
with sshtunnel.SSHTunnelForwarder(
("server address", port),
ssh_username="user",
ssh_password="password",
remote_bind_address=("127.0.0.1",3306),
) as server:
print(server.local_bind_port)
with mysql.connector.connect(
user="user",
password="password",
host="localhost",
database="database",
port=server.local_bind_port
) as connection:
print(connection)
There's too many steps to list, but I'm wondering if the "connector" setup plays a difference even for SSH. Maybe you have to create a connector as shown here (notice how the instructions in "Private IP" tab are different than on your local computer). Then, configure Cloud Functions to use that connector. Make sure you also use the right port.
A Serverless VPC Access connector handles communication to your VPC
network. To connect directly with private IP, you need to:
Make sure that the Cloud SQL instance created above has a private IP
address. If you need to add one, see the Configuring private IP page
for instructions.
Create a Serverless VPC Access connector in the same
VPC network as your Cloud SQL instance. Unless you're using Shared
VPC, a connector must be in the same project and region as the
resource that uses it, but the connector can send traffic to resources
in different regions. Serverless VPC Access supports communication to VPC networks connected via Cloud VPN and VPC Network Peering. Serverless VPC Access does not support legacy networks.
Configure Cloud Functions to use the connector.
Connect using your
instance's private IP and port 3306.
Keep in mind, this "unknown" error could also very well be due to the Cloud SQL Admin API not being enabled here. As a matter of fact, make sure you follow that entire page as it's a broad question.
Let us know what worked for this type of error.

Connect AWS RDS (psql) in AWS Lambda

I wrote a simple lambda function in python to fetch some data from AWS RDS. PostgreSQL is the database engines.
conn = psycopg2.connect(host=hostname, user=username, password=password, dbname=db_name, connect_timeout=50)
I did like this. But it didn't work. Always returns an error like this
Response:
{
"errorMessage": "2018-06-06T11:28:53.775Z Task timed out after 3.00 seconds"
}
How can I resolve this??
It is most probably timing-out because the network connection cannot be established.
If you wish to connect to the database via a public IP address, then your Lambda function should not be connected to the VPC. Instead, the connection will go from Lambda, via the internet, into the VPC and to the Amazon RDS instance.
If you wish to connect to the database via a private IP address, then your Lambda function should be configured to use the same VPC as the Amazon RDS instance.
In both cases, the connection should be established using the DNS Name of the RDS instance, but it will resolve differently inside and outside of the VPC.
Finally, the Security Group associated with the Amazon RDS instance needs to allow the incoming connection. This, too, will vary depending upon whether the request is coming from public or private space. You can test by opening the security group to 0.0.0.0/0 and, if it works, then try to restrict it to the minimum possible range.

What is the hostname for a Google Cloud PostgreSQL instance?

I'm trying to connect to a PostgreSQL database on Google Cloud using SQLAlchemy. Making a connection to the database requires specifying a database URL of the form: dialect+driver://username:password#host:port/database
I know what the dialect + driver is (postgresql), I know my username and password, and I know the database name. But I don't know how to find the host and port on the Google Cloud console. I've tried using the instance connection name, but that doesn't seem to work. Anyone know where I can find this info on Google Cloud?
Hostname: Please use instance's IP address. There is "IPv4 address" field on the instance overview page in the Cloud Console, e.g. https://console.cloud.google.com/sql/instances/[Instance Name]/overview
Port: we use default PostgreSQL port, 5432. I think it is possible to just omit it from the connection string.
Please also see "Connecting psql Client Using IP Addresses" page in our docs.
Hostname is the Public IP address.
I want to assume you're making use of the Postgres instance private IP address. That can be gotten from Cloud SQL instances dashboard.

How to get an public address for Azure SDK Python, before VM creation

I'm aware that the public ip is only generated after you set the vm. But is there a way to force the public ip to be dinamically created BEFORE the vm creation.
Mainly, I need to use the ip to generate the machine's name.
Or, is there a way to update the machine's name, before creation? I can find any information on this.
You can create the public IP before you create the VM. Then when creating the VM, associate the public IP to the VM's NIC.
Add Andrés Nava - .NET's answer. You should create a static Public IP before you create VM. Please refer to this SDK article.
Gets or sets PrivateIP allocation method (Static/Dynamic)
When you create a static Public IP, it is associated a Public IP address and the IP address does not change. But if you create a Dynamic Public IP, it is not associated a IP address when you create the resource and the IP address will change when you stop VM.

Python AWS lambda function connecting to RDS mysql: Timeout error

When the python lambda function is executed I get "Task timed out after 3.00 seconds" error. I am trying the same example function.
When I try to run the same code from eclipse it works fine and I can see the query result. Same way I can connect to the db instance from local-machine Mysql workbench without any issues.
I tried creating a role with with full administrator access policy for this lambda function and even then its not working fine. The db instance has a vpc and I just added my local ip address there using the edit CIDR option so I can access the instance through my local machine workbench. For VPC, subnet and security group parameter in lambda function I gave the same values as I have in the RDS db instance.
I have also increased the timeout for lambda function and still I see the timeout error.
Any input would be appreciated.
For VPC, subnet and security group parameter in lambda function I gave the same values as I have in the RDS db instance.
Security groups don't automatically trust their own members to access other members.
Add a rule to this security group for "MySQL" (TCP port 3306) but instead of specifying an IP address, start typing s g into the box and select the id of the security group that you are adding the rule to -- so that the group is self-referential.
Note that this is probably not the correct long-term fix, because if your Lambda function needs to access the Internet or most AWS services, the Lambda function needs to be on a private subnet behind a NAT device. That does not describe the configuration of the subnet where your RDS instance is currently configured, because you mentioned adding your local IP to allow access to RDS. That suggests your RDS is on a public subnet.
See also Why Do We Need Private Subnets in VPC for a better understanding of public vs. private subnets.

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