Openstack API not providing precise data - rest

Question

I am using Openstack - Stein in CentOS 7.9
I was using python to collect data about the openstack nova performance, like server names and id in the openstack project, i have 3 instance(server) created, i can see all three instance in openstack cli, but when i connect to api mentioned in openstack, it provides no data or less data.
I refereed openstack documentation here
[root#centos-vm1 kavin(keystone_admin)]# openstack server list
+--------------------------------------+-----------------+--------+----------------------------------------+-------+----------+
| ID | Name | Status | Networks | Image | Flavor |
+--------------------------------------+-----------------+--------+----------------------------------------+-------+----------+
| 08cf6226-0303-4b4c-ba53-10af79b81dae | test_instance_3 | ACTIVE | test_networ_3=10.150.0.8 | | m1.tiny |
| 9986f205-82b3-4cbb-bcdc-fb32eab97c83 | test_instance_1 | ACTIVE | test_networ_2=10.100.0.5, x.x.x.x | | m1.small |
| d1c0f520-8540-432c-8fe1-554390fd79bf | test_instance_2 | ACTIVE | test_networ_1=10.50.0.8 | | m1.small |
+--------------------------------------+-----------------+--------+----------------------------------------+-------+----------+
My python code:
import requests,json
from six.moves.urllib.parse import urljoin
identity = {
"methods": ["password"],
"password": {
"user": {
"name": "admin",
"domain": { "id": "default" },
"password": "xxxxxxxxxxxxxxx"
}
}
}
OS_AUTH_URL = 'http://x.x.x.x:5000/v3'
data = {'auth': {'identity': identity}}
HEADERS = {'Content-Type': 'application/json', 'scope': 'unscoped'}
r = requests.post(
OS_AUTH_URL+'/auth/tokens',
headers = HEADERS,
json = data,
verify = False
)
auth_token = r.headers['X-Subject-Token'] # i got auth token
# server list
NOVA_URL="http://x.x.x.x:8774/v2.1"
HEADERS = {"X-Auth-Token" : str(auth_token)}
r = requests.get(
NOVA_URL+'/servers',
headers = HEADERS,
)
r.raise_for_status()
print(r.json())
Output :
{'servers': []}
help me, collect accurate data using api calls, thanks

Answer 1

According to api-ref List Servers doc, maybe you should add the project scope in the request.
By default the servers are filtered using the project ID associated with the authenticated request.
In my opinion, you could use openstacksdk to execute the operation, simply with the Connection object and list_servers method.
import openstack
conn = openstack.connect(
region_name='example-region',
auth_url='http://x.x.x.x:5000/v3/',
username='amazing-user',
password='super-secret-password',
project_id='33...b5',
domain_id='05...03'
)
servers = conn.list_servers()