2 Lease element

The <lease> element is used by Haizea's XML-RPC API to send lease requests to Haizea, and to return lease information to the client. It is also used in the LWF format to describe lease requests.

The <lease> element has two attributes: id, a unique integer identifier (assigned by Haizea), and preemptible, indicating whether the lease can be safely preempted (yes or no)

 
<lease id="..." preemptible="...">
  ...
</lease>

The <lease> element has four child elements:

• <nodes> (as described above): Specifies the nodes requested by the lease, and the capacity required in these nodes.
• <duration>: The requested duration of the lease. This element has a single attribute time which is used to specify a duration with format DD:HH:MM.SS (DD: days; HH: hours; MM: minutes; SS: seconds)
• <start>: The requested started time of the lease. If the element is empty, this means the requested starting time is unspecified, and it is up to Haizea to determine the starting time on a best-effort basis:

   
  <start/>
  

  If an exact starting time is specified, then this element has an <exact> child element with a time attribute specifying the starting time using an ISO timestamp (YYYY-MM-DD HH:MM:SS) or a relative starting time (+DD:HH:MM:SS), which is interpreted as being relative to the time the lease is submitted to Haizea.

   
  <start>
    <exact time="..."/>
  </exact>
  

  If the lease is requested to start immediately, then this element has an empty <now> child element:

   
  <start>
    <now/>
  </exact>
  

• <software>: The software environment required by the lease. Currently, Haizea only supports specifying a lease's software environment as being contained inside a disk image:

   
  <software>
    <disk-image id="..." size="..."/>
  </software>
  

  The disk-image child element specifies information about the disk image: id, a unique identifier, and size, its size in megabytes.

  Additionally, the software environment can be left unspecified, which means that Haizea can assume that setting up the software environment will be handled by another entity:

   
  <software>
    <none/>
  </software>
  

1 Example

The following specifies a best-effort lease, requesting one node with one CPU and 1024 MB of memory, for one hour, and a software environment contained in diskimage foobar1.img (a 1GB image).

 
<lease id="1" preemptible="true">
  <nodes>
    <node-set numnodes="1">
      <res amount="100" type="CPU"/>
      <res amount="1024" type="Memory"/>
    </node-set>
  </nodes>
  <start/>
  <duration time="01:00:00"/>
  <software>
    <disk-image id="foobar1.img" size="1024"/>
  </software>
</lease>