Store and publish Juju charms.

To start using the charm store, run the following:

go get github.com/juju/charmstore

The project uses godeps (https://launchpad.net/godeps) to manage Go dependencies. After installing the application, you can update the dependencies to the revision specified in the dependencies.tsv file with the following:

make deps

Use make create-deps to update the dependencies file.

A couple of system packages are required in order to set up a charm store development environment. To install them, run the following:

make sysdeps

At this point, from the root of this branch, run the command::

make install

The command above builds and installs the charm store binaries, and places them in $GOPATH/bin. This is the list of the installed commands:

• charmload: populate the database with charms from Launchpad;
• charmd: start the charm store server;
• charm-admin: manage published charms.

A description of each command can be found below.

Run make check to test the application. Run make help to display help about all the available make targets.

The charm store creates a MongoDB database named "juju" and stores info about charms in the MongoDB "juju.charms" collection. Also charm files are stored in a GridFS named "juju.charmfs".

To populate the database with the charms published in Launchpad, run the following command:

charmload cmd/charmd/config.yaml

Note: the operation takes a large amount of time and disk space to complete: at the time of this writing it takes ~2:30h and ~4GB to store ~1050 charms, but this can vary significantly based on your machine/connection speed. The process can be stopped by typing ^C. To check the imported charm count, you can run the following:

mongo --eval "db.getSiblingDB('juju').charms.count()"

Once the charms database is fully populated, it is possible to interact with charm data using the charm store server. It can be started with the following command:

charmd cmd/charmd/config.yaml

The same result can be achieved more easily by running make server.

At this point the server starts listening on port 8080 (as specified in the config YAML file). The server exposes the following API:

A GET call to /charm-info returns info about one or more charms, including its canonical URL, revision, SHA256 checksum and VCS revision digest. The returned info is in JSON format. For instance a request to /charm-info?charms=cs:trusty/juju-gui returns the following response:

{"cs:trusty/juju-gui": {
    "canonical-url": "cs:trusty/juju-gui",
    "revision": 3,
    "sha256": "a15c77f3f92a0fb7b61e9...",
    "digest": jeff.pihach@canonical.com-20140612210347-6cc9su1jqjkhbi84"
}}

A GET call to /charm-event returns info about an event occurred in the life of the specified charm(s). Currently two types of events are logged: "published" (a charm has been published and it's available in the store) and "publish-error" (an error occurred while importing the charm). E.g. a call to /charm-event?charms=cs:trusty/juju-gui generates the following JSON response:

{"cs:trusty/juju-gui": {
    "kind": "published",
    "revision": 3,
    "digest": "jeff.pihach@canonicalcom-20140612210347-6cc9su1jqjkhbi84",
    "time": "2014-06-16T14:41:19Z"
}}

The charm API provides the ability to download a charm as a Zip archive, given the charm identifier. For instance, it is possible to download the Juju GUI charm by performing a GET call to /charm/trusty/juju-gui-42. Both the revision and OS series can be omitted, e.g. /charm/juju-gui will download the last revision of the Juju GUI charm with support to the more recent Ubuntu LTS series.

Stats can be retrieved by calling /stats/counter/{key} where key is a query that specifies the counter stats to calculate and return.

For instance, a call to /stats/counter/charm-bundle:* returns the number of times a charm has been downloaded from the store. To get the same value for a specific charm, it is possible to filter the results by passing the charm series and name, e.g. /stats/counter/charm-bundle:trusty:juju-gui.

The results can be grouped by specifying the by query (possible values are day and week), and time delimited using the start and stop queries.

It is also possible to list the results by passing list=1. For example, a GET call to /stats/counter/charm-bundle:trusty:*?by=day&list=1 returns an aggregated count of trusty charms downloads, grouped by charm and day, similar to the following:

charm-bundle:trusty:juju-gui  2014-06-17  5
charm-bundle:trusty:mysql     2014-06-17  1

The charm-admin command is used to manage the store contents. Currently the only implemented sub-command is delete-charm, which removes a charm from the store, e.g.:

charm-admin delete-charm --config cmd/charmd/config.yaml --url trusty/mysql

Run charm-admin help for the complete command's help.