make cloud-config modules configurable by cloud-config

The list of cloud-config modules is now kept in cloud config itself.
There is a builtin list in cloudinit, which is overrideable by 
 /etc/cloud/cloud.cfg or user data cloud-config.

This should make the modules more easily added or removed (as no code
needs to be edited now)

Basic summary of changes:
 - move CloudConfig.py -> cloudinit/CloudConfig/__init__.py
 - split cloud-config modules into their own files named
   cloudinit/CloudConfig/cc_<name>.py
 - remove all the upstart/cloud-config-* scripts, replacing them with
   upstart/cloud-config.conf

1 files changed, 131 insertions, 0 deletions

diff --git a/cloudinit/CloudConfig/cc_mounts.py b/cloudinit/CloudConfig/cc_mounts.py
new file mode 100644
index 00000000..8bd16240
--- /dev/null
+++ b/cloudinit/CloudConfig/cc_mounts.py
@@ -0,0 +1,131 @@
+import cloudinit.util as util
+import os
+import re
+import string
+
+def handle(name,cfg,cloud,log,args):
+    # these are our default set of mounts
+    defmnts = [ [ "ephemeral0", "/mnt", "auto", "defaults", "0", "0" ],
+                [ "swap", "none", "swap", "sw", "0", "0" ] ]
+
+    # fs_spec, fs_file, fs_vfstype, fs_mntops, fs-freq, fs_passno
+    defvals = [ None, None, "auto", "defaults", "0", "0" ]
+
+    cfgmnt = [ ]
+    if cfg.has_key("mounts"):
+        cfgmnt = cfg["mounts"]
+
+    for i in range(len(cfgmnt)):
+        # skip something that wasn't a list
+        if not isinstance(cfgmnt[i],list): continue
+
+        # workaround, allow user to specify 'ephemeral'
+        # rather than more ec2 correct 'ephemeral0'
+        if cfgmnt[i][0] == "ephemeral":
+            cfgmnt[i][0] = "ephemeral0"
+
+        newname = cfgmnt[i][0]
+        if not newname.startswith("/"):
+            newname = cloud.device_name_to_device(cfgmnt[i][0])
+        if newname is not None:
+            cfgmnt[i][0] = newname
+        else:
+            # there is no good way of differenciating between
+            # a name that *couldn't* exist in the md service and
+            # one that merely didnt
+            # in order to allow user to specify 'sda3' rather
+            # than '/dev/sda3', go through some hoops
+            ok = False
+            for f in [ "/", "sd", "hd", "vd", "xvd" ]:
+                if cfgmnt[i][0].startswith(f):
+                    ok = True
+                    break
+            if not ok:
+                cfgmnt[i][1] = None
+
+    for i in range(len(cfgmnt)):
+        # fill in values with 
+        for j in range(len(defvals)):
+            if len(cfgmnt[i]) <= j:
+                cfgmnt[i].append(defvals[j])
+            elif cfgmnt[i][j] is None:
+                cfgmnt[i][j] = defvals[j]
+
+        if not cfgmnt[i][0].startswith("/"):
+            cfgmnt[i][0]="/dev/%s" % cfgmnt[i][0]
+
+        # if the second entry in the list is 'None' this
+        # clears all previous entries of that same 'fs_spec'
+        # (fs_spec is the first field in /etc/fstab, ie, that device)
+        if cfgmnt[i][1] is None:
+            for j in range(i):
+                if cfgmnt[j][0] == cfgmnt[i][0]:
+                    cfgmnt[j][1] = None
+
+
+    # for each of the "default" mounts, add them only if no other
+    # entry has the same device name
+    for defmnt in defmnts:
+        devname = cloud.device_name_to_device(defmnt[0])
+        if devname is None: continue
+        if devname.startswith("/"):
+            defmnt[0] = devname
+        else:
+            defmnt[0] = "/dev/%s" % devname
+
+        cfgmnt_has = False
+        for cfgm in cfgmnt:
+            if cfgm[0] == defmnt[0]:
+                cfgmnt_has = True
+                break
+        
+        if cfgmnt_has: continue
+        cfgmnt.append(defmnt)
+
+
+    # now, each entry in the cfgmnt list has all fstab values
+    # if the second field is None (not the string, the value) we skip it
+    actlist = filter(lambda x: x[1] is not None, cfgmnt)
+
+    if len(actlist) == 0: return
+
+    comment="comment=cloudconfig"
+    cc_lines = [ ]
+    needswap = False
+    dirs = [ ]
+    for line in actlist:
+        # write 'comment' in the fs_mntops, entry,  claiming this
+        line[3]="%s,comment=cloudconfig" % line[3]
+        if line[2] == "swap": needswap = True
+        if line[1].startswith("/"): dirs.append(line[1])
+        cc_lines.append('\t'.join(line))
+
+    fstab_lines = [ ]
+    fstab=open("/etc/fstab","r+")
+    ws = re.compile("[%s]+" % string.whitespace)
+    for line in fstab.read().splitlines():
+        try:
+            toks = ws.split(line)
+            if toks[3].find(comment) != -1: continue
+        except:
+            pass
+        fstab_lines.append(line)
+
+    fstab_lines.extend(cc_lines)
+        
+    fstab.seek(0)
+    fstab.write("%s\n" % '\n'.join(fstab_lines))
+    fstab.truncate()
+    fstab.close()
+
+    if needswap:
+        try: util.subp(("swapon", "-a"))
+        except: log.warn("Failed to enable swap")
+
+    for d in dirs:
+        if os.path.exists(d): continue
+        try: os.makedirs(d)
+        except: log.warn("Failed to make '%s' config-mount\n",d)
+
+    try: util.subp(("mount","-a"))
+    except: pass