Mimic is an API-compatible mock service for Openstack Compute and Rackspace's implementation of Identity and Cloud Load balancers. It is backed by in-memory data structure rather than a potentially expensive database.

Mimic helps with:

• fast set-up
• instant response
• cost efficient
• enables offline developmenet
• enables ability to test unusual behaviors/errors of an api
• acts as a central repository for mocked responses from services

https://github.com/rackerlabs/mimic/blob/master/mimic/rest/nova_api.py

1. LIST servers - Lists servers on the tenant, in mimic
2. POST server - Creates a server in mimic (look at the 'Errors or unusual behaviors supported for compute' below)
3. GET server - Returns the server, if it exists in mimic else returns a 404
4. DELETE server - Deletes the server, if it exists in mimic else returns 404
5. LIST addresses - Lists the private and public Ips for the given server. 404 if not found.
6. GET image - If the image ID is anything but what is listed in the mimic presets, invalid_image_ref returns 200. Else returns a 400.
7. GET flavor - If the flavor ID is anything but what is listed in the mimic presets, invalid_flavor_ref returns 200. Else returns a 400.
8. GET limits - Returns only the absolute limits for compute

Based on the metadata (mimic_presets) provided when a server is being created, a server can be made to behave as follows:

• Fail with the given response message and response code
• Go into an error state on creation
• Remain in building state for the specified amount of time
• Fails to delete the server, with the specified response code for the number of times specified
• Returns 'image not found' or 'flavor not found' responses for specified IDs

Eg: Request for create server that remains in building for 120 seconds:

{ "server" : { "name" : "api-test-server-1", "imageRef" : "3afe97b2-26dc-49c5-a2cc-a2fc8d80c001", "flavorRef" : "2", "metadata": {"server_building": 120} } }

https://github.com/rackerlabs/mimic/blob/master/mimic/rest/auth_api.py

1. Authenticate - Given a tenant id, username and password, returns the service catalog with links to compute and load balancer links within mimic, and a test token.
2. Impersonate user (Admin call) - Given a token created by mimic in the header, returns a test token for the username.
3. GET endpoints - Given token created by mimic, returns the service catalog for that user.

https://github.com/rackerlabs/mimic/blob/master/mimic/rest/loadbalancer_api.py

1. LIST load balancers - Lists the load balancers created in mimic
2. POST load balancer - Creates a load balancer (look at the 'Errors or unusual behaviors supported for cloud load balancers' below)
3. GET load balancer - Returns the load balancer if it exists, else 404
4. DELETE load balancer - Deletes the load balancer if it exists, else returns 404
5. LIST nodes - Lists the nodes on the load balancer
6. POST node - Creates a node on the load balancer
7. GET node - Returns the node if it exists, else returns 404
8. DELETE node - Deletes the node if it exists, else returns 404

Based on key and value of the metadata (mimic_presets) provided when a load balancer is being created, a load balancer can be made to behave as follows:

• Remain in 'BUILD' state for the specified amount of time
• Load balancer goes into 'PENDING-UPDATE' state on every add/delete node for the specified amout of time
• Load balancer goes into 'PENDING-DELETE' state on delete load balancer for the specified amout of time
• Load balancer goes into an error state on creation

Eg: Request for create load balancer that is expected to go into 'PENDING-UPDATE' state on every add/delete node, for 20 seconds:

{"loadBalancer": {"name": "a-new-loadbalancer2", "protocol": "HTTP", "virtualIps": [{"type": "PUBLIC"}], "metadata": [{"key": "lb_pending_update", "value": 20}], "nodes": []}}

• support XML
• validate the auth token

1. create a cloud server with an image that by default comes with python 2.7 (eg: ubuntu 12.04) and ssh into it
2. git clone https://github.com/rackerlabs/mimic.git
3. pip install -r requirements.txt from within the mimic folder (if there is a gcc error, apt-get install python-dev)
4. cd into mimic or add the mimic to the PYTHONPATH and run twistd -n mimic