API¶

The complete API for cloudmesh is available through:

Cloud Database¶

Cloudmesh contains a convenient Cloud database to store its objects. It also contains simple functions to synchronize the database with objects that are found in clouds. This includes images, flavors, and virtual machines.

The clouds are defined in ~/.cloudmesh/cloudmesh.yaml

All you need to do is to create a cm object:

cm = CloudmeshDatabase(cm_user="gregor")

To update a specific set of cloud object such as the flavors on the cloud india you simply can say:

cm.update("flavor", "india")

Other examples include

cm.update(“image”, “india”) cm.update(“vm”, “india”)

Multiple updates and clouds can be introduced with a parametrized call:

cm.update("vm,flavor,image", "india,aws,azure")

In our example all clouds specified update the virtual machines, images, and flavors in the database. Please note that the keywords used are singular.

Once the data is in the database its easy to query it either with the native query functions or with specialized find functions exposed to the cm object.

To query for example a vm with the name “gregor-001” you can use

vm = cm.find(“vm”, name=”gregor-001”).first()

Using the method:

d = cm.o_to_d(vm)

returns a dict in the object d. Alternatively you could also use the native database format and for example get information via:

vm.name
vm.status
....

In some cases using dicts is more convenient. You may want to chose if you use the native form or the dict representation.

Updating an element in the database¶

The cloud related data have a number of attributes that make it easy to identify them. The most important one is ‘cm_id` which presents in human readable format a unique id for the object in the database.

The id is generated fir the getID method.

Let us assume the following setup for our example:

cm = CloudmeshDatabase(cm_user="gregor")

this will create a cm database object in which the user gregor stores its values. First we need to get a dictionary that we may want to store and modify in the database. We can obtain such an object changeme from a live cloud with:

cloud = OpenStack_libcloud(
    "acloudnamedefinedin_cludmesh.yaml",
    cm_user="yourusernameonthecloud")
flavors = cloud.list("flavor", output="flat")

internal_id = "1"

changeme = flavors[internal_id]

However such an object could also be created by hand. To store the element in the database we first need to generate a unique cm_id. In our case we use the cloud object type (here flavor), the unique internal id that we obtain for each flavor, and the name of the cloud on which the object belongs to.:

changeme["cm_id"] = cm.getID("flavor", internal_id, "india")

Just to be sure lest set the type to flavor:

changeme["cm_type"] = "flavor"

Now let us change the label of the object to:

changeme["label"] = "newlabel"

To update the new object to the database use:

cm.update_from_dict(f)
cm.save()