REST API for APEL

The APEL project provides accounting for the Indigo DataCloud project. It is written in Python and uses MySQL.

Overview

APEL Cloud Accounting can account for the usage of OpenNebula and OpenStack instances. Accounting "collectors" need to be installed on machines with access to the underlying Cloud infrastructure. The collectors can be found here.

The collectors produce "Usage Records" in the APEL-Cloud v0.2 or v0.4 message formats. Information about these format can be found here.

These records need to be sent as POST requests to the REST endpoint .../api/v1/cloud/record, where ... is the machine hosting the docker image. A POST request requires an X.509 certificate to authenticate the request. The hostname, which should be the same as the common name (CN) contained in the X.509 certificate, must be listed as a provider here or be given special access via the ALLOWED_TO_POST enviroment variable for the request to be authorized. For details of how to be added to the CMDB service list, please refer to the CMDB documentation.

Accepted records are summarised twice daily. These summaries can be accessed with a GET request to .../api/v1/cloud/record/summary. Summaries can be filtered using key=value pairs. See Supported key=value pairs for a list of valid supported key=value pairs. A GET request requires an IAM access token be included in the request. This token is then sent to the IAM to authenticate the ID of the service requesting access to the summary. This ID needs to be in ALLOWED_FOR_GET in yaml/apel_rest_interface.env for access to be authorized.

It is currently expected that only the QoS/SLA tool will interact with these summaries.

Features of Version 1.5.0

• Accept APEL-Cloud v0.2 and v0.4 usage records via POST requests to the REST endpoint .../api/v1/cloud/record
• Provide access to summaries via GET requests to REST endpoint .../api/v1/cloud/record/summary

Running the Docker image on Centos 7 and Ubuntu 16.04

We recommend using the Docker image to run the Accounting server and REST interface. As such, having Docker installed is a prerequisite.

See Ubuntu 16.04 Instructions or Centos 7 Instructions for details of how to install Docker. There is no requirement to undertake the 'Post-installation steps for Linux'.

We also recommend using Docker Compose or Anisble to deploy the containers.

• See the offical Docker Compose documentation for details of how to install docker-compose.
• See the offical Ansible documentation for details of how to install Ansible.

The instructions below are for both Docker Compose and Ansibe.

1. Download the compressed source code from here, it does not matter where the source code is downloaded to. As the source code contains schemas and yaml files needed for deploying via docker-compose or ansible, you will need to unzip the source code and then cd into the inflated directory.

2. Register the service as a protected resource with the Indigo Identity Access Management (IAM) service. See this section for instructions, before proceeding to step 3.

3. Populate the following variables in yaml/apel_rest_interface.env

   DJANGO_SECRET_KEY: The Django server requires its own "secret". A typical secret key
                      will be a 50 character long random sequence of alphanumeric
                      and special characters. This secret will be used for JSON object
                      signing and other cryptographic functions like creating CSRF keys.
   
   PROVIDERS_URL: Points to the JSON list of Resource Providers
   
   IAM_URL: The introspect URL for the IAM repsonsible for token based authN/authZ
   
   SERVER_IAM_ID: An IAM ID corresponding to this instance, used to validate tokens.
   
   SERVER_IAM_SECRET: An IAM secret corresponding to this instance, used to validate tokens.
   
   ALLOWED_TO_POST: A (Python) list of X.509 HostDNs allowed to submit POST requests,
                    in addition to those listed by the PROVIDERS_URL.
                    (e.g. ['/C=XX/O=XX/OU=XX/L=XX/CN=special_host.test'])
   
   BANNED_FROM_POST: A (Python) list of X.509 HostDNs banned from submitting POST requests,
                    even if they are listed by the PROVIDERS_URL.
                    (e.g. ['/C=XX/O=XX/OU=XX/L=XX/CN=banned_host.test'])
   
   ALLOWED_FOR_GET: A (Python) list of IAM service IDs allowed to submit GET requests.
                    (e.g. ['ac2f23e0-8103-4581-8014-e0e82c486e36'])
   

4. Populate the following variables in yaml/mysql.env

   MYSQL_ROOT_PASSWORD: The APEL server will use this to communicate with the database. If run_container.sh
                        is deploying the database (which by default it will be), the database root password
                        is set to this.
   
   MYSQL_PASSWORD: The APEL server will use this to communicate with the database. If run_container.sh
                   is deploying the database (which by default it will be) the APEL user password
                   is set to this.
   

5. MYSQL_PASSWORD will also need to be added to the password field docker/etc/apel/clouddb.cfg and docker/etc/mysql/my.cnf

6. Before the REST interface will start, a certificate needs to be added to the container. This can be done by placing a certificate (apache.crt) and key (apache.key) under /etc/httpd/ssl/ on the host machine (be careful to preserve correct .crt/.key file permissions). /etc/httpd/ssl/ will be mounted into the container by docker-compose. Note: You may need to create the /etc/httpd/ssl/ directory.

7. If you are running Docker as a non-root user, you will need to make docker/etc/cron.d owned by root. This is because this directory gets mounted into the container and it needs to be owned by root for cron jobs in the container to run.

   sudo chown -R root docker/etc/cron.d
   

8. Launch the containers.

• With Docker Compose:

  It is recommeded to wait 1 minute after launching the database in order for it to configure fully before launching the APEL containers

  docker-compose -f yaml/docker-compose.yaml up -d --force-recreate apel_mysql
  # Wait 1 minute
  docker-compose -f yaml/docker-compose.yaml up -d --force-recreate apel_server
  docker-compose -f yaml/docker-compose.yaml up -d --force-recreate apel_rest_interface
  

• With Ansible:

  First, replace <working directory> in yaml/ansible.yaml with the absolute file path of the decompressed source code, then run the command below.

  ansible-playbook yaml/ansible.yml
  

9. Navigate a web browser to https://<hostname>/api/v1/cloud/record/summary