====== Django API ======

**General Information**

Interacting with the Django Python API. 

API Reference: https://docs.djangoproject.com/en/1.11/ref/models/querysets/

**Checklist**
  * [[django_install|Django Installed]]
  * [[django_configuration|Django Configured]]

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====== Imports and Settings ======

Imports and settings to add to your Python script in order to use your Django App's built in API.

\\
Import and Settings
<code python>
#!/usr/bin/python

# Required module for sys.path.append
import sys
# Required module for os.environ
import os

# Import Django WSGI App Loading capabilities
from django.core.wsgi import get_wsgi_application

##- Configure Django Settings to point to your App -##
# sys.path = where manage.py is
sys.path.append('/home/django/myprojecthere')

# Settings Module = projectname.settings
os.environ["DJANGO_SETTINGS_MODULE"] = 'myprojecthere.settings'
application = get_wsgi_application()

# Import Django App Model (from 'myapphere' app)
from myapphere.models import AssetEntry
</code>

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====== Using Your Apps API ======

Different ways to get your app data.

===== Load Objects ====

Objects can be retrieved just like in views.py.

Field lookup reference: https://docs.djangoproject.com/en/1.11/ref/models/querysets/#field-lookups

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**Load All Objects**
<code python>
# Load all assets (just like in views.py)
asset_list = AssetEntry.objects.order_by('asset_type', 'asset_env', 'asset_name')

# Print all names (see your models.py for available fields)
for node in asset_list:
  print(node.asset_name)
</code>

\\
**Load Multiple Objects that Match a filter**
<code python>
# Load with a filter on device type (get all servers)
asset_list = AssetEntry.objects.filter(asset_type__iexact="servers")

# Print all retrieved objects
for node in asset_list:
    print("-> Node Name is: " + node.asset_name)
    print("Device Type is: " + node.asset_type)
</code>

\\
**Load Single Object**
<code python>
# Load single object
single_asset = AssetEntry.objects.get(asset_name__iexact="server99")

# Print the name and os
print("Single Asset: " + single_asset.asset_name + " (OS: " + single_asset.asset_os + ")")
</code>

===== Add New Objects ====

Create a new object and then save it to the database.

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**Two Steps: Create object and then save it to the database**
<code python>
# Set variables that will be used to create a new object
new_name = "server99"
new_type = "Servers"
new_description = "API Added Server"
new_env = "Prod"
new_os = "CentOS 7"
new_hardware = "Virtual"

# Create the new object
new_entry = AssetEntry(asset_name = new_name, asset_type = new_type, asset_description = new_description, asset_env = new_env, asset_os = new_os, asset_hardware = new_hardware)

# Attempt to add new object to the database
try:
  new_entry.save()
  print("--> Entry added successfully.")
except:
  print("---> ERROR adding entry!")
</code>

\\
**One Step: Create object in the database**
<code python>
# Set variables that will be used to create a new object
new_name = "server99"
new_type = "Servers"
new_description = "API Added Server"
new_env = "Prod"
new_os = "CentOS 7"
new_hardware = "Virtual"

# Create the new object directly
new_entry = AssetEntry.objects.create(asset_name = new_name, asset_type = new_type, asset_description = new_description, asset_env = new_env, asset_os = new_os, asset_hardware = new_hardware)
</code>

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===== Change Existing Objects ====

Changing an existing object in the database.
<code bash>
# Load all assets (just like in views.py)
asset_list = AssetEntry.objects.order_by('asset_type', 'asset_env', 'asset_name')

# Change server99's OS to Ubuntu 18.04
for node in asset_list:
  if node.asset_name == "server99":
    node.asset_os = "Ubuntu 18.04"
    
    # Attempt to save object change to the database
    try:                                                                                       
      node.save()
      print("--> Change saved successfully.")
    except:
      print("---> ERROR saving change!")
</code>

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===== Delete Objects ====

Deleting objects using the API.
<code python>
# Retrieve a single object
single_asset = AssetEntry.objects.get(asset_name__iexact="server99")

# Delete the object
single_asset.delete()
</code>

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