In order to replace usage of the shell just for 'cd %s; ...' we need to
be able to specify the working directory for childs.

The patch also changes the default working directory (when not
specified) to "/", as opposed to the current dir; since the daemos run
with cwd=/ anyway, this should not change things.

Reviewed-by: imsnah

The same code will be used by the HTTP client.

Reviewed-by: iustinp

While working on the HTTP client class, I wanted to use Mainloop
before deciding to use threads instead.

- Add docstrings
- Rename "quit" to "running", move it to a local variable
- Support adding and removing I/O listeners while running
  (e.g. to add/remove listeners from OnIO(…) calls)
- Allow user of the class to disable signal handlers
- Flag to exit once all listeners are gone

Reviewed-by: iustinp

This is an expected error message and will be used in two places.

Reviewed-by: iustinp

It is based on the WorkerPool class which is already used for the job
queue and master daemon. Each request must be encapsulated in an
instance of HttpClientRequest, which will then be passed to
HttpClientManager for processing. Upon completion, the request object
contains the response or error message.

While not yet enabled, the HTTP client implementation has been designed
with HTTP/1.1 and keep-alive in mind. For now it only uses HTTP/1.0,
though.

HttpClientManager will likely need more changes when integrating with
the RPC layer. SSL will also be integrated in a second step.

Reviewed-by: iustinp, ultrotter

Reviewed-by: iustinp

The _WaitForSync call changed in r1794 but the GrowDisk call wasn't updated
then. This makes GrowDisk work in trunk.

Reviewed-by: iustinp

As a preparation for the new HTTP client class, add more constants
to ganeti.http.

Reviewed-by: iustinp

Reviewed-by: imsnah

Reviewed-by: imsnah

The newer_than variable can be either None or an int, and we normalize
it to an integer previously and save it in the 'serial' variable, which
should be used instead.

Reviewed-by: imsnah

Reviewed-by: imsnah

This patch converts all of backend.py to epydoc formatting.

Reviewed-by: imsnah

The return from this error path is a dict, but the actual return value
(on the non-error handling) is a list of dicts. Change accordingly.

Reviewed-by: imsnah

Found while reviewing documentation.

Reviewed-by: ultrotter

Reviewed-by: iustinp

This fixes a few doc issues and converts a few docstrings to epydoc.

Reviewed-by: imsnah

Currently we launch processes via the shell in a few places only to
redirect standard output and error to a log file ("&> $file"). It is
better to do such redirection from within RunCmd itself.

This patch splits RunCmd in two parts, the setup and the execution part,
the latter being implemented in two different functions depending on
whether we write to a file or not.

We also update the unittests with this new case.

Reviewed-by: imsnah

Reviewed-by: killerfoxi

At the same time, simplify the interface a bit by not using a tuple.

Reviewed-by: killerfoxi, ultrotter

Currently we don't catch the JobSubmittedException (although the code to
format it nicely is there). The patch adds the exception name to the
catch list and makes --submit work.

Reviewed-by: imsnah

We want to export the disk index as some OSes will only want to export
the first disk (or the second one, etc.), even if we have multiple
disks.

The patch also updates the backend.ExportSnapshot docstring.

Reviewed-by: ultrotter

Reviewed-by: imsnah

It turned out that clients not sending a full request will stop
us from responding to further requests. This patch leverages the
situation a bit by always forking before handling the request,
but we still have DoS situations.

Reviewed-by: ultrotter

We don't have timers yet, hence waking up is not needed at all.

Reviewed-by: ultrotter

RAPI: Export beparams as dict. The patch also enables LUQueryInstances to accept beparams as valid field.

Reviewed-by: iustinp

Reviewed-by: iustinp

Previously we used to handle only one disk. Now we'll import all the
ones present in the export, in order, on the instance's disks. Any disk
which was present on the original instance but wasn't exported is just
skipped in the target instance.

Reviewed-by: iustinp

- Change ImportOSIntoInstance not to get any "os_disk" and "swap_disk"
  arguments but to accept multiple target images to import, and to
  return a list of booleans with the result of each import
- Change the relevant rpc call and the only caller to conform
- Pass arguments to the import script through the environment
- Run one import os script for each disk image, passing an IMPORT_DEVICE

Reviewed-by: iustinp

We pass the data via the environment rather than on the command line, as
API 10 says. All the rest remains the same, and we export just one disk,
as the master calls this function for every snapshotted disk.

Reviewed-by: iustinp

Rather than just snapshotting the "sda" disk, we'll snapshot all of the
instance disks. If we can't snapshot a disk for any reason we'll log an
error and proceed anyway: in this case the resulting export will miss a
disk. This also changes all the warning messages to self.LogWarning().

Reviewed-by: iustinp

Reviewed-by: iustinp

Reviewed-by: iustinp

We change some messages which are obviously intended for the user to use
the proc.Log* functions instead of (only) the logging ones.

We also fix some wrong uses of feedback_fn.

Reviewed-by: imsnah

As discussed previously, many of the routinges in cmdlib.py are using
logging functions as a carry-over from 1.2 (when these also showed the
message on stderr/to the user), instead of actually warning the user.

This patch extends the syntax for Processor.LogInfo/LogWarning in order
to be easier to use them.

Reviewed-by: imsnah

Please configure your editors to strip it, or enable your git hooks...

Reviewed-by: ultrotter

During cluster init, set the default hypervisor to be used for instances.
Ensure that the default hypervisor belongs to the set enabled hypervisors
for this cluster. Also fix a small bug with setting the default enabled
hypervisor list.

Reviewed-by: imsnah

The two main multi-node job queue RPC calls (jobqueue_update,
jobqueue_rename) are converted to address-based calls, in order to speed
up queue changes. For this, we need to change the _nodes attribute on
the jobqueue to be a dict {name: ip}, instead of a set.

Reviewed-by: imsnah

This patch allows rpc.call_upload_file to use addresses (if passed), and
also converts the ConfigWriter._DistributeConfig to pass them, since
this is an often-done operation.

Reviewed-by: imsnah

This patch converts all non-staticmethods rpc calls to pass addresses to
the Client calls.

This is done via two new small helpers. These functions also deal with
nodes that are not (yet) in the configuration file, and pass None for
the address instead (which allow NodeControllers to do resolving).

Reviewed-by: imsnah