From a1992ba586acc7545a7edb37130727e19e4d1065 Mon Sep 17 00:00:00 2001
From: Chris Behrens <cbehrens@codestud.com>
Date: Wed, 30 Mar 2011 13:13:04 -0700
Subject: [PATCH] Add ed leafe's code for the inject_file agent plugin method
 that somehow got lost (fixes bug 741246). Update TimeoutError string for i18n

---
 .../xenserver/xenapi/etc/xapi.d/plugins/agent | 79 ++++++++++++++++++-
 1 file changed, 75 insertions(+), 4 deletions(-)

diff --git a/plugins/xenserver/xenapi/etc/xapi.d/plugins/agent b/plugins/xenserver/xenapi/etc/xapi.d/plugins/agent
index 94eaabe73362..3522df49d5f0 100755
--- a/plugins/xenserver/xenapi/etc/xapi.d/plugins/agent
+++ b/plugins/xenserver/xenapi/etc/xapi.d/plugins/agent
@@ -22,6 +22,7 @@
 # XenAPI plugin for reading/writing information to xenstore
 #
 
+import base64
 try:
     import json
 except ImportError:
@@ -31,6 +32,7 @@ import random
 import subprocess
 import tempfile
 import time
+import uuid
 
 import XenAPIPlugin
 
@@ -102,6 +104,75 @@ def resetnetwork(self, arg_dict):
     xenstore.write_record(self, arg_dict)
 
 
+@jsonify
+def inject_file(self, arg_dict):
+    """Expects a file path and the contents of the file to be written. Both
+    should be base64-encoded in order to eliminate errors as they are passed
+    through the stack. Writes that information to xenstore for the agent,
+    which will decode the file and intended path, and create it on the
+    instance. The original agent munged both of these into a single entry;
+    the new agent keeps them separate. We will need to test for the new agent,
+    and write the xenstore records to match the agent version. We will also
+    need to test to determine if the file injection method on the agent has
+    been disabled, and raise a NotImplemented error if that is the case.
+    """
+    b64_path = arg_dict["b64_path"]
+    b64_file = arg_dict["b64_file"]
+    request_id = arg_dict["id"]
+    if self._agent_has_method("file_inject"):
+        # New version of the agent.  Agent should receive a 'value'
+        # key whose value is a dictionary containing 'b64_path' and
+        # 'b64_file'.  See old version below.
+        arg_dict["value"] = json.dumps({"name": "file_inject",
+                "value": {"b64_path": b64_path, "b64_file": b64_file}})
+    elif self._agent_has_method("injectfile"):
+        # Old agent requires file path and file contents to be
+        # combined into one base64 value.
+        raw_path = base64.b64decode(b64_path)
+        raw_file = base64.b64decode(b64_file)
+        new_b64 = base64.b64encode("%s,%s") % (raw_path, raw_file)
+        arg_dict["value"] = json.dumps({"name": "injectfile",
+                "value": new_b64})
+    else:
+        # Either the methods don't exist in the agent, or they
+        # have been disabled.
+        raise NotImplementedError("NOT IMPLEMENTED: Agent does not support"
+                " file injection.")
+    arg_dict["path"] = "data/host/%s" % request_id
+    xenstore.write_record(self, arg_dict)
+    try:
+        resp = _wait_for_agent(self, request_id, arg_dict)
+    except TimeoutError, e:
+        raise PluginError("%s" % e)
+    return resp
+
+
+def _agent_has_method(self, method):
+    """Check that the agent has a particular method by checking its
+    features.  Cache the features so we don't have to query the agent
+    every time we need to check.
+    """
+    try:
+        self._agent_methods
+    except AttributeError:
+        self._agent_methods = []
+    if not self._agent_methods:
+        # Haven't been defined
+        tmp_id = str(uuid.uuid4())
+        dct = {}
+        dct["value"] = json.dumps({"name": "features", "value": ""})
+        dct["path"] = "data/host/%s" % tmp_id
+        xenstore.write_record(self, dct)
+        try:
+            resp = _wait_for_agent(self, tmp_id, dct)
+        except TimeoutError, e:
+            raise PluginError("%s" % e)
+        response = json.loads(resp)
+        # The agent returns a comma-separated list of methods.
+        self._agent_methods = response.split(",")
+    return method in self._agent_methods
+
+
 def _wait_for_agent(self, request_id, arg_dict):
     """Periodically checks xenstore for a response from the agent.
     The request is always written to 'data/host/{id}', and
@@ -119,9 +190,8 @@ def _wait_for_agent(self, request_id, arg_dict):
             # First, delete the request record
             arg_dict["path"] = "data/host/%s" % request_id
             xenstore.delete_record(self, arg_dict)
-            raise TimeoutError(
-                    "TIMEOUT: No response from agent within %s seconds." %
-                    AGENT_TIMEOUT)
+            raise TimeoutError(_("TIMEOUT: No response from agent within"
+                    " %s seconds.") % AGENT_TIMEOUT)
         ret = xenstore.read_record(self, arg_dict)
         # Note: the response for None with be a string that includes
         # double quotes.
@@ -136,4 +206,5 @@ if __name__ == "__main__":
     XenAPIPlugin.dispatch(
         {"key_init": key_init,
         "password": password,
-        "resetnetwork": resetnetwork})
+        "resetnetwork": resetnetwork,
+        "inject_file": inject_file})