Docker containers run from Docker images, which can be distributed through so-called Docker registries. The currently available support for searching images in registries is however limited. Available registries (e.g., Docker Hub) only permit searching images “by name”, i.e. by specifying a term occurring in the image name, in the image description or in the name of the user that created such image. DOCKERFINDER permits searching for images based on multiple attributes, e.g., image name, image size, or supported software distributions.

1. DOCKERFINDER: MULTI-ATTRIBUTE
SEARCH OF DOCKER IMAGES
Antonio Brogi, Davide Neri, and Jacopo Soldani
Department of Computer Science, University of Pisa, Italy
{name.surname}@di.unipi.it

2. Deployment scenario with Docker
How we can search a
Docker image that satisfies
these requirements ?
200 MB
Multi-attribute search of Docker images 2
Application
Docker
Registry

3. Searching Docker images (1)
$ docker search –stars=10 java
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
java Java is a concurrent ... 1334 [OK]
anapsix/alpine-java Oracle Java 8 (and 7) ... 197 [OK]
isuper/java-oracle This repository contai... 52 [OK]
Usage: docker search [OPTIONS] TERM
Search the Docker Hub for images
Options:
-f, --filter filter Filter output based on conditions provided
--help Print usage
--limit int Max number of search results (default 25)
--no-trunc Don't truncate output
Search by command line
Example
Multi-attribute search of Docker images 3

4. Searching Docker images (2)
Search by Web (e.g. Docker Hub)
Multi-attribute search of Docker images 4

5. Deployment scenario with Docker
200 MB
Multi-attribute search of Docker images 5
Application
Docker
Registry

6. DockerFinder - Solution
Attributes:
• Software distributions supported (e.g. python 2.7, java 1.8).
• Size – size of the images.
• Stars – vote of users.
• Pulls – number of downloads.
DockerFinder is a microservice-based prototype that permits
searching Docker images based on multiple attributes.
Multi-attribute search of Docker images 6

7. DockerFinder – High level overview
DockerFinder main steps:
1. Download and analyse
Docker images.
2. Generate and store the
description in local
database.
3. Userssearch the images
(RESTful API and GUI).
Multi-attribute search of Docker images 7

8. DockerFinder – High level overview
DockerFinder main steps:
1. Download and analyse
Docker images.
2. Generate and store the
descriptions in a local
database.
3. Users search the images
(RESTful API and GUI).
Multi-attribute search of Docker images 8

9. DockerFinder – High level overview
DockerFinder main steps:
1. Download and analyse
Docker images.
2. Generate and store the
descriptions in a local
database.
3. Users can search the
images (API and GUI).
Multi-attribute search of Docker images 9

10. DockerFinder – High level overview
DockerFinder main steps:
1. Download and analyse
Docker images.
2. Generate and store the
descriptions in a local
database.
3. Users submit multi-
attribute queries.
Multi-attribute search of Docker images 10

11. • Set of independent,
runnable, self-deployable
microservices.
• Communication with
lightweight mechanisms
(e.g. HTTP, AMQP).
• Adopted mainly for:
• Scalability,
• Manageability, and
• Integrability.
API
API
API
AMQP
API
Multi-attribute search of Docker images 11
DockerFinder:
Microservice-based
architecture
Admin
User

12. Storage part
Images Service: two
RESTful APIs:
• api/images/
manage the images’
descriptions.
• /search submit
multi-attribute queries
Images DB
stores the images’
descriptions
Multi-attribute search of Docker images 12
Admin
User

13. Analysis part
Crawler: crawls the name of
the images.
Message Broker: enqueues
the name of the images.
Scanner: pulls and analyse
the images producing
descriptions.
Checker: enforce eventual
consistency between local
and remote images.
Multi-attribute search of Docker images 13
Admin
User

14. Scanner – Extract software distributions
Given an image i to be analysed:
1. Create a “sleeping” container
2. For each software distribution <command, option, regex>
(e.g., < python, --version, [0-9]+[.][0-9]*[.0-9]*> ), execute:
1. Parse with the regex the result: if match the image support that command.
match = Search(regex, result)
ID = docker run i sleep 1d
result = docker exec ID command option
Multi-attribute search of Docker images 14

15. Discovery part
Software service and
Software DB
• /api/software
manage the list of
software.
GUI
Web-based graphical
user interface.
Search API
• /search proxy the
requests to the
storage.
Multi-attribute search of Docker images 15
Admin
User

16. DockerFinder – GUI
Multi-attribute search of Docker images 16

17. DockerFinder deployments (with Docker)
Multi-container Docker
application:
• Each component is shipped
in a Docker container.
• Single host deployment
• Multi-host deployment
https://github.com/di-unipi-socc/DockerFinder
Multi-attribute search of Docker images 17
Admin
User

18. Deployments configurations
Single host Multiple host
Multi-attribute search of Docker images 18

19. Scanners scalability
Test set-up:
• All “latest” official images pulled locally.
• Scanning of 100 images (fixed).
• 16 software searched in each image.
$ docker-compose scale scanner=<x>
Multi-attribute search of Docker images 19

20. Summary of contributions
DockerFinder :
1. Enhanced search of Docker images based on multi-attributes
(software distributions, stars, pulls, size).
2. Designed as a microservices-based architecture (scalability,
manageability, integrability)
Multi-attribute search of Docker images 20

21. Conclusions – Possible extensions
Storage space
(caching)
Multi-attribute search of Docker images 21
Multi-registries crawling
DockerFinder
Security policies

22. Future perspective
DockerFinder as a general framework with the following
features:
1. Customizable analysis function (in the scanner) for
generating personalized datasets image descriptions.
2. Analysis of other container technologies (e.g., Rkt).
Multi-attribute search of Docker images 22

23. THANK YOU FOR YOUR
ATTENTION
Davide Neri
davide.neri@di.unipi.it
Multi-attribute search of Docker images 23

24. Related work
• Docker Store: Clusters images by categories (e.g. Database images,
programming languages images).
• JFrog artifactory: supports Docker and users can assign custom properties
to Docker images.
• “Automatic capturing and systematic usage of DevOps knowledge for
cloud applications”. Wettinger. A knowledge base of heterogeneous
DevOps solutions.
Docker Finder generates descriptions extracting features from “inside” the
images in a fully-automated way.
Multi-attribute search of Docker images 24

25. Reference (some)
• Enrico Bacis, Simone Mutti, Steven Capelli, and Stefano Paraboschi. DockerPolicyModules:
Mandatory access control for docker containers.
• Nicola Dragoni, Saverio Giallorenzo, Alberto Lluch-Lafuente, Manuel Mazzara, Fabrizio Montesi,
Ruslan Mustafin, and Larisa Safina. Microservices: yesterday, today, and tomorrow.
• Martin Fowler and James Lewis. Microservices.
• Hui Kang, Michael Le, and Shu Tao. Container and microservice driven design for cloud
infrastructure devops.
• Johannes Wettinger, Vasilios Andrikopoulos, and Frank Leymann. Automated capturing and
systematic usage of devops knowledge for cloud applications.
Multi-attribute search of Docker images 25