X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fceph%2Fsrc%2Fmon%2FPaxosService.h;fp=src%2Fceph%2Fsrc%2Fmon%2FPaxosService.h;h=0000000000000000000000000000000000000000;hb=7da45d65be36d36b880cc55c5036e96c24b53f00;hp=54e4ea3815e9fffcdf9be9183b187a38ef9ca732;hpb=691462d09d0987b47e112d6ee8740375df3c51b2;p=stor4nfv.git

diff --git a/src/ceph/src/mon/PaxosService.h b/src/ceph/src/mon/PaxosService.h
deleted file mode 100644
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--- a/src/ceph/src/mon/PaxosService.h
+++ /dev/null
@@ -1,910 +0,0 @@
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-// vim: ts=8 sw=2 smarttab
-/*
- * Ceph - scalable distributed file system
- *
- * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
- *
- * This is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License version 2.1, as published by the Free Software 
- * Foundation.  See file COPYING.
- * 
- */
-
-#ifndef CEPH_PAXOSSERVICE_H
-#define CEPH_PAXOSSERVICE_H
-
-#include "include/Context.h"
-#include "Paxos.h"
-#include "Monitor.h"
-#include "MonitorDBStore.h"
-
-class Monitor;
-class Paxos;
-
-/**
- * A Paxos Service is an abstraction that easily allows one to obtain an
- * association between a Monitor and a Paxos class, in order to implement any
- * service.
- */
-class PaxosService {
-  /**
-   * @defgroup PaxosService_h_class Paxos Service
-   * @{
-   */
- public:
-  /**
-   * The Monitor to which this class is associated with
-   */
-  Monitor *mon;
-  /**
-   * The Paxos instance to which this class is associated with
-   */
-  Paxos *paxos;
-  /**
-   * Our name. This will be associated with the class implementing us, and will
-   * be used mainly for store-related operations.
-   */
-  string service_name;
-  /**
-   * If we are or have queued anything for proposal, this variable will be true
-   * until our proposal has been finished.
-   */
-  bool proposing;
-
-  bool need_immediate_propose = false;
-
-protected:
-  /**
-   * Services implementing us used to depend on the Paxos version, back when
-   * each service would have a Paxos instance for itself. However, now we only
-   * have a single Paxos instance, shared by all the services. Each service now
-   * must keep its own version, if so they wish. This variable should be used
-   * for that purpose.
-   */
-  version_t service_version;
-
- private:
-  /**
-   * Event callback responsible for proposing our pending value once a timer 
-   * runs out and fires.
-   */
-  Context *proposal_timer;
-  /**
-   * If the implementation class has anything pending to be proposed to Paxos,
-   * then have_pending should be true; otherwise, false.
-   */
-  bool have_pending; 
-
-  /**
-   * health checks for this service
-   *
-   * Child must populate this during encode_pending() by calling encode_health().
-   */
-  health_check_map_t health_checks;
-protected:
-  /**
-   * format of our state in leveldb, 0 for default
-   */
-  version_t format_version;
-
-public:
-  const health_check_map_t& get_health_checks() {
-    return health_checks;
-  }
-
-  /**
-   * @defgroup PaxosService_h_callbacks Callback classes
-   * @{
-   */
-  /**
-   * Retry dispatching a given service message
-   *
-   * This callback class is used when we had to wait for some condition to
-   * become true while we were dispatching it.
-   *
-   * For instance, if the message's version isn't readable, according to Paxos,
-   * then we must wait for it to become readable. So, we just queue an
-   * instance of this class onto the Paxos::wait_for_readable function, and
-   * we will retry the whole dispatch again once the callback is fired.
-   */
-  class C_RetryMessage : public C_MonOp {
-    PaxosService *svc;
-  public:
-    C_RetryMessage(PaxosService *s, MonOpRequestRef op_) :
-      C_MonOp(op_), svc(s) { }
-    void _finish(int r) override {
-      if (r == -EAGAIN || r >= 0)
-	svc->dispatch(op);
-      else if (r == -ECANCELED)
-        return;
-      else
-	assert(0 == "bad C_RetryMessage return value");
-    }
-  };
-
-  /**
-   * @}
-   */
-
-  /**
-   * @param mn A Monitor instance
-   * @param p A Paxos instance
-   * @param name Our service's name.
-   */
-  PaxosService(Monitor *mn, Paxos *p, string name) 
-    : mon(mn), paxos(p), service_name(name),
-      proposing(false),
-      service_version(0), proposal_timer(0), have_pending(false),
-      format_version(0),
-      last_committed_name("last_committed"),
-      first_committed_name("first_committed"),
-      full_prefix_name("full"), full_latest_name("latest"),
-      cached_first_committed(0), cached_last_committed(0)
-  {
-  }
-
-  virtual ~PaxosService() {}
-
-  /**
-   * Get the service's name.
-   *
-   * @returns The service's name.
-   */
-  string get_service_name() { return service_name; }
-
-  /**
-   * Get the store prefixes we utilize
-   */
-  virtual void get_store_prefixes(set<string>& s) {
-    s.insert(service_name);
-  }
-  
-  // i implement and you ignore
-  /**
-   * Informs this instance that it should consider itself restarted.
-   *
-   * This means that we will cancel our proposal_timer event, if any exists.
-   */
-  void restart();
-  /**
-   * Informs this instance that an election has finished.
-   *
-   * This means that we will invoke a PaxosService::discard_pending while
-   * setting have_pending to false (basically, ignore our pending state) and
-   * we will then make sure we obtain a new state.
-   *
-   * Our state shall be updated by PaxosService::_active if the Paxos is
-   * active; otherwise, we will wait for it to become active by adding a 
-   * PaxosService::C_Active callback to it.
-   */
-  void election_finished();
-  /**
-   * Informs this instance that it is supposed to shutdown.
-   *
-   * Basically, it will instruct Paxos to cancel all events/callbacks and then
-   * will cancel the proposal_timer event if any exists.
-   */
-  void shutdown();
-
-private:
-  /**
-   * Update our state by updating it from Paxos, and then creating a new
-   * pending state if need be.
-   *
-   * @remarks We only create a pending state we our Monitor is the Leader.
-   *
-   * @pre Paxos is active
-   * @post have_pending is true if our Monitor is the Leader and Paxos is
-   *	   active
-   */
-  void _active();
-
-public:
-  /**
-   * Propose a new value through Paxos.
-   *
-   * This function should be called by the classes implementing 
-   * PaxosService, in order to propose a new value through Paxos.
-   *
-   * @pre The implementation class implements the encode_pending function.
-   * @pre have_pending is true
-   * @pre Our monitor is the Leader
-   * @pre Paxos is active
-   * @post Cancel the proposal timer, if any
-   * @post have_pending is false
-   * @post propose pending value through Paxos
-   *
-   * @note This function depends on the implementation of encode_pending on
-   *	   the class that is implementing PaxosService
-   */
-  void propose_pending();
-
-  /**
-   * Let others request us to propose.
-   *
-   * At the moment, this is just a wrapper to propose_pending() with an
-   * extra check for is_writeable(), but it's a good practice to dissociate
-   * requests for proposals from direct usage of propose_pending() for
-   * future use -- we might want to perform additional checks or put a
-   * request on hold, for instance.
-   */
-  void request_proposal() {
-    assert(is_writeable());
-
-    propose_pending();
-  }
-  /**
-   * Request service @p other to perform a proposal.
-   *
-   * We could simply use the function above, requesting @p other directly,
-   * but we might eventually want to do something to the request -- say,
-   * set a flag stating we're waiting on a cross-proposal to be finished.
-   */
-  void request_proposal(PaxosService *other) {
-    assert(other != NULL);
-    assert(other->is_writeable());
-
-    other->request_proposal();
-  }
-
-  /**
-   * Dispatch a message by passing it to several different functions that are
-   * either implemented directly by this service, or that should be implemented
-   * by the class implementing this service.
-   *
-   * @param m A message
-   * @returns 'true' on successful dispatch; 'false' otherwise.
-   */
-  bool dispatch(MonOpRequestRef op);
-
-  void refresh(bool *need_bootstrap);
-  void post_refresh();
-
-  /**
-   * @defgroup PaxosService_h_override_funcs Functions that should be
-   *					     overridden.
-   *
-   * These functions should be overridden at will by the class implementing
-   * this service.
-   * @{
-   */
-  /**
-   * Create the initial state for your system.
-   *
-   * In some of ours the state is actually set up elsewhere so this does
-   * nothing.
-   */
-  virtual void create_initial() = 0;
-
-  /**
-   * Query the Paxos system for the latest state and apply it if it's newer
-   * than the current Monitor state.
-   */
-  virtual void update_from_paxos(bool *need_bootstrap) = 0;
-
-  /**
-   * Hook called after all services have refreshed their state from paxos
-   *
-   * This is useful for doing any update work that depends on other
-   * service's having up-to-date state.
-   */
-  virtual void post_paxos_update() {}
-
-  /**
-   * Init on startup
-   *
-   * This is called on mon startup, after all of the PaxosService instances'
-   * update_from_paxos() methods have been called
-   */
-  virtual void init() {}
-
-  /**
-   * Create the pending state.
-   *
-   * @invariant This function is only called on a Leader.
-   * @remarks This created state is then modified by incoming messages.
-   * @remarks Called at startup and after every Paxos ratification round.
-   */
-  virtual void create_pending() = 0;
-
-  /**
-   * Encode the pending state into a bufferlist for ratification and
-   * transmission as the next state.
-   *
-   * @invariant This function is only called on a Leader.
-   *
-   * @param t The transaction to hold all changes.
-   */
-  virtual void encode_pending(MonitorDBStore::TransactionRef t) = 0;
-
-  /**
-   * Discard the pending state
-   *
-   * @invariant This function is only called on a Leader.
-   *
-   * @remarks This function is NOT overridden in any of our code, but it is
-   *	      called in PaxosService::election_finished if have_pending is
-   *	      true.
-   */
-  virtual void discard_pending() { }
-
-  /**
-   * Look at the query; if the query can be handled without changing state,
-   * do so.
-   *
-   * @param m A query message
-   * @returns 'true' if the query was handled (e.g., was a read that got
-   *	      answered, was a state change that has no effect); 'false' 
-   *	      otherwise.
-   */
-  virtual bool preprocess_query(MonOpRequestRef op) = 0;
-
-  /**
-   * Apply the message to the pending state.
-   *
-   * @invariant This function is only called on a Leader.
-   *
-   * @param m An update message
-   * @returns 'true' if the update message was handled (e.g., a command that
-   *	      went through); 'false' otherwise.
-   */
-  virtual bool prepare_update(MonOpRequestRef op) = 0;
-  /**
-   * @}
-   */
-
-  /**
-   * Determine if the Paxos system should vote on pending, and if so how long
-   * it should wait to vote.
-   *
-   * @param[out] delay The wait time, used so we can limit the update traffic
-   *		       spamming.
-   * @returns 'true' if the Paxos system should propose; 'false' otherwise.
-   */
-  virtual bool should_propose(double &delay);
-
-  /**
-   * force an immediate propose.
-   *
-   * This is meant to be called from prepare_update(op).
-   */
-  void force_immediate_propose() {
-    need_immediate_propose = true;
-  }
-
-  /**
-   * @defgroup PaxosService_h_courtesy Courtesy functions
-   *
-   * Courtesy functions, in case the class implementing this service has
-   * anything it wants/needs to do at these times.
-   * @{
-   */
-  /**
-   * This is called when the Paxos state goes to active.
-   *
-   * On the peon, this is after each election.
-   * On the leader, this is after each election, *and* after each completed
-   * proposal.
-   *
-   * @note This function may get called twice in certain recovery cases.
-   */
-  virtual void on_active() { }
-
-  /**
-   * This is called when we are shutting down
-   */
-  virtual void on_shutdown() {}
-
-  /**
-   * this is called when activating on the leader
-   *
-   * it should conditionally upgrade the on-disk format by proposing a transaction
-   */
-  virtual void upgrade_format() { }
-
-  /**
-   * this is called when we detect the store has just upgraded underneath us
-   */
-  virtual void on_upgrade() {}
-
-  /**
-   * Called when the Paxos system enters a Leader election.
-   *
-   * @remarks It's a courtesy method, in case the class implementing this
-   *	      service has anything it wants/needs to do at that time.
-   */
-  virtual void on_restart() { }
-  /**
-   * @}
-   */
-
-  /**
-   * Tick.
-   */
-  virtual void tick() {}
-
-  /**
-   * Get health information
-   *
-   * @param summary list of summary strings and associated severity
-   * @param detail optional list of detailed problem reports; may be NULL
-   */
-  virtual void get_health(list<pair<health_status_t,string> >& summary,
-			  list<pair<health_status_t,string> > *detail,
-			  CephContext *cct) const { }
-
-  void encode_health(const health_check_map_t& next,
-		     MonitorDBStore::TransactionRef t) {
-    bufferlist bl;
-    ::encode(next, bl);
-    t->put("health", service_name, bl);
-    mon->log_health(next, health_checks, t);
-  }
-  void load_health();
-
- private:
-  /**
-   * @defgroup PaxosService_h_store_keys Set of keys that are usually used on
-   *					 all the services implementing this
-   *					 class, and, being almost the only keys
-   *					 used, should be standardized to avoid
-   *					 mistakes.
-   * @{
-   */
-  const string last_committed_name;
-  const string first_committed_name;
-  const string full_prefix_name;
-  const string full_latest_name;
-  /**
-   * @}
-   */
-
-  /**
-   * @defgroup PaxosService_h_version_cache Variables holding cached values
-   *                                        for the most used versions (first
-   *                                        and last committed); we only have
-   *                                        to read them when the store is
-   *                                        updated, so in-between updates we
-   *                                        may very well use cached versions
-   *                                        and avoid the overhead.
-   * @{
-   */
-  version_t cached_first_committed;
-  version_t cached_last_committed;
-  /**
-   * @}
-   */
-
-  /**
-   * Callback list to be used whenever we are running a proposal through
-   * Paxos. These callbacks will be awaken whenever the said proposal
-   * finishes.
-   */
-  list<Context*> waiting_for_finished_proposal;
-
- public:
-
-  /**
-   * Check if we are proposing a value through Paxos
-   *
-   * @returns true if we are proposing; false otherwise.
-   */
-  bool is_proposing() {
-    return proposing;
-  }
-
-  /**
-   * Check if we are in the Paxos ACTIVE state.
-   *
-   * @note This function is a wrapper for Paxos::is_active
-   *
-   * @returns true if in state ACTIVE; false otherwise.
-   */
-  bool is_active() {
-    return
-      !is_proposing() &&
-      (paxos->is_active() || paxos->is_updating() || paxos->is_writing());
-  }
-
-  /**
-   * Check if we are readable.
-   *
-   * This mirrors on the paxos check, except that we also verify that
-   *
-   *  - the client hasn't seen the future relative to this PaxosService
-   *  - this service isn't proposing.
-   *  - we have committed our initial state (last_committed > 0)
-   *
-   * @param ver The version we want to check if is readable
-   * @returns true if it is readable; false otherwise
-   */
-  bool is_readable(version_t ver = 0) {
-    if (ver > get_last_committed() ||
-	!paxos->is_readable(0) ||
-	get_last_committed() == 0)
-      return false;
-    return true;
-  }
-
-  /**
-   * Check if we are writeable.
-   *
-   * We consider to be writeable iff:
-   *
-   *  - we are not proposing a new version;
-   *  - we are ready to be written to -- i.e., we have a pending value.
-   *  - paxos is (active or updating or writing or refresh)
-   *
-   * @returns true if writeable; false otherwise
-   */
-  bool is_writeable() {
-    return is_write_ready(); 
-  }
-
-  /**
-   * Check if we are ready to be written to.  This means we must have a
-   * pending value and be active.
-   *
-   * @returns true if we are ready to be written to; false otherwise.
-   */
-  bool is_write_ready() {
-    return is_active() && have_pending;
-  }
-
-  /**
-   * Wait for a proposal to finish.
-   *
-   * Add a callback to be awaken whenever our current proposal finishes being
-   * proposed through Paxos.
-   *
-   * @param c The callback to be awaken once the proposal is finished.
-   */
-  void wait_for_finished_proposal(MonOpRequestRef op, Context *c) {
-    if (op)
-      op->mark_event_string(service_name + ":wait_for_finished_proposal");
-    waiting_for_finished_proposal.push_back(c);
-  }
-  void wait_for_finished_proposal_ctx(Context *c) {
-    MonOpRequestRef o;
-    wait_for_finished_proposal(o, c);
-  }
-
-  /**
-   * Wait for us to become active
-   *
-   * @param c The callback to be awaken once we become active.
-   */
-  void wait_for_active(MonOpRequestRef op, Context *c) {
-    if (op)
-      op->mark_event_string(service_name + ":wait_for_active");
-
-    if (!is_proposing()) {
-      paxos->wait_for_active(op, c);
-      return;
-    }
-    wait_for_finished_proposal(op, c);
-  }
-  void wait_for_active_ctx(Context *c) {
-    MonOpRequestRef o;
-    wait_for_active(o, c);
-  }
-
-  /**
-   * Wait for us to become readable
-   *
-   * @param c The callback to be awaken once we become active.
-   * @param ver The version we want to wait on.
-   */
-  void wait_for_readable(MonOpRequestRef op, Context *c, version_t ver = 0) {
-    /* This is somewhat of a hack. We only do check if a version is readable on
-     * PaxosService::dispatch(), but, nonetheless, we must make sure that if that
-     * is why we are not readable, then we must wait on PaxosService and not on
-     * Paxos; otherwise, we may assert on Paxos::wait_for_readable() if it
-     * happens to be readable at that specific point in time.
-     */
-    if (op)
-      op->mark_event_string(service_name + ":wait_for_readable");
-
-    if (is_proposing() ||
-	ver > get_last_committed() ||
-	get_last_committed() == 0)
-      wait_for_finished_proposal(op, c);
-    else {
-      if (op)
-        op->mark_event_string(service_name + ":wait_for_readable/paxos");
-
-      paxos->wait_for_readable(op, c);
-    }
-  }
-
-  void wait_for_readable_ctx(Context *c, version_t ver = 0) {
-    MonOpRequestRef o; // will initialize the shared_ptr to NULL
-    wait_for_readable(o, c, ver);
-  }
-
-  /**
-   * Wait for us to become writeable
-   *
-   * @param c The callback to be awaken once we become writeable.
-   */
-  void wait_for_writeable(MonOpRequestRef op, Context *c) {
-    if (op)
-      op->mark_event_string(service_name + ":wait_for_writeable");
-
-    if (is_proposing())
-      wait_for_finished_proposal(op, c);
-    else if (!is_write_ready())
-      wait_for_active(op, c);
-    else
-      paxos->wait_for_writeable(op, c);
-  }
-  void wait_for_writeable_ctx(Context *c) {
-    MonOpRequestRef o;
-    wait_for_writeable(o, c);
-  }
-
-  
-  /**
-   * @defgroup PaxosService_h_Trim Functions for trimming states
-   * @{
-   */
-  /**
-   * trim service states if appropriate
-   *
-   * Called at same interval as tick()
-   */
-  void maybe_trim();
-
-  /**
-   * Auxiliary function to trim our state from version @p from to version
-   * @p to, not including; i.e., the interval [from, to[
-   *
-   * @param t The transaction to which we will add the trim operations.
-   * @param from the lower limit of the interval to be trimmed
-   * @param to the upper limit of the interval to be trimmed (not including)
-   */
-  void trim(MonitorDBStore::TransactionRef t, version_t from, version_t to);
-
-  /**
-   * encode service-specific extra bits into trim transaction
-   *
-   * @param tx transaction
-   * @param first new first_committed value
-   */
-  virtual void encode_trim_extra(MonitorDBStore::TransactionRef tx,
-				 version_t first) {}
-
-  /**
-   * Get the version we should trim to.
-   *
-   * Should be overloaded by service if it wants to trim states.
-   *
-   * @returns the version we should trim to; if we return zero, it should be
-   *	      assumed that there's no version to trim to.
-   */
-  virtual version_t get_trim_to() {
-    return 0;
-  }
-
-  /**
-   * @}
-   */
-  /**
-   * @defgroup PaxosService_h_Stash_Full
-   * @{
-   */
-  virtual bool should_stash_full();
-  /**
-   * Encode a full version on @p t
-   *
-   * @note We force every service to implement this function, since we strongly
-   *	   desire the encoding of full versions.
-   * @note Services that do not trim their state, will be bound to only create
-   *	   one full version. Full version stashing is determined/controled by
-   *	   trimming: we stash a version each time a trim is bound to erase the
-   *	   latest full version.
-   *
-   * @param t Transaction on which the full version shall be encoded.
-   */
-  virtual void encode_full(MonitorDBStore::TransactionRef t) = 0;
-
-  /**
-   * @}
-   */
-
-  /**
-   * Cancel events.
-   *
-   * @note This function is a wrapper for Paxos::cancel_events
-   */
-  void cancel_events() {
-    paxos->cancel_events();
-  }
-
-  /**
-   * @defgroup PaxosService_h_store_funcs Back storage interface functions
-   * @{
-   */
-  /**
-   * @defgroup PaxosService_h_store_modify Wrapper function interface to access
-   *					   the back store for modification
-   *					   purposes
-   * @{
-   */
-  void put_first_committed(MonitorDBStore::TransactionRef t, version_t ver) {
-    t->put(get_service_name(), first_committed_name, ver);
-  }
-  /**
-   * Set the last committed version to @p ver
-   *
-   * @param t A transaction to which we add this put operation
-   * @param ver The last committed version number being put
-   */
-  void put_last_committed(MonitorDBStore::TransactionRef t, version_t ver) {
-    t->put(get_service_name(), last_committed_name, ver);
-
-    /* We only need to do this once, and that is when we are about to make our
-     * first proposal. There are some services that rely on first_committed
-     * being set -- and it should! -- so we need to guarantee that it is,
-     * specially because the services itself do not do it themselves. They do
-     * rely on it, but they expect us to deal with it, and so we shall.
-     */
-    if (!get_first_committed())
-      put_first_committed(t, ver);
-  }
-  /**
-   * Put the contents of @p bl into version @p ver
-   *
-   * @param t A transaction to which we will add this put operation
-   * @param ver The version to which we will add the value
-   * @param bl A bufferlist containing the version's value
-   */
-  void put_version(MonitorDBStore::TransactionRef t, version_t ver,
-		   bufferlist& bl) {
-    t->put(get_service_name(), ver, bl);
-  }
-  /**
-   * Put the contents of @p bl into a full version key for this service, that
-   * will be created with @p ver in mind.
-   *
-   * @param t The transaction to which we will add this put operation
-   * @param ver A version number
-   * @param bl A bufferlist containing the version's value
-   */
-  void put_version_full(MonitorDBStore::TransactionRef t,
-			version_t ver, bufferlist& bl) {
-    string key = mon->store->combine_strings(full_prefix_name, ver);
-    t->put(get_service_name(), key, bl);
-  }
-  /**
-   * Put the version number in @p ver into the key pointing to the latest full
-   * version of this service.
-   *
-   * @param t The transaction to which we will add this put operation
-   * @param ver A version number
-   */
-  void put_version_latest_full(MonitorDBStore::TransactionRef t, version_t ver) {
-    string key = mon->store->combine_strings(full_prefix_name, full_latest_name);
-    t->put(get_service_name(), key, ver);
-  }
-  /**
-   * Put the contents of @p bl into the key @p key.
-   *
-   * @param t A transaction to which we will add this put operation
-   * @param key The key to which we will add the value
-   * @param bl A bufferlist containing the value
-   */
-  void put_value(MonitorDBStore::TransactionRef t,
-		 const string& key, bufferlist& bl) {
-    t->put(get_service_name(), key, bl);
-  }
-
-  /**
-   * Put integer value @v into the key @p key.
-   *
-   * @param t A transaction to which we will add this put operation
-   * @param key The key to which we will add the value
-   * @param v An integer
-   */
-  void put_value(MonitorDBStore::TransactionRef t,
-		 const string& key, version_t v) {
-    t->put(get_service_name(), key, v);
-  }
-
-  /**
-   * @}
-   */
-
-  /**
-   * @defgroup PaxosService_h_store_get Wrapper function interface to access
-   *					the back store for reading purposes
-   * @{
-   */
-
-  /**
-   * @defgroup PaxosService_h_version_cache Obtain cached versions for this
-   *                                        service.
-   * @{
-   */
-  /**
-   * Get the first committed version
-   *
-   * @returns Our first committed version (that is available)
-   */
-  version_t get_first_committed() const{
-    return cached_first_committed;
-  }
-  /**
-   * Get the last committed version
-   *
-   * @returns Our last committed version
-   */
-  version_t get_last_committed() const{
-    return cached_last_committed;
-  }
-
-  /**
-   * @}
-   */
-
-  /**
-   * Get the contents of a given version @p ver
-   *
-   * @param ver The version being obtained
-   * @param bl The bufferlist to be populated
-   * @return 0 on success; <0 otherwise
-   */
-  virtual int get_version(version_t ver, bufferlist& bl) {
-    return mon->store->get(get_service_name(), ver, bl);
-  }
-  /**
-   * Get the contents of a given full version of this service.
-   *
-   * @param ver A version number
-   * @param bl The bufferlist to be populated
-   * @returns 0 on success; <0 otherwise
-   */
-  virtual int get_version_full(version_t ver, bufferlist& bl) {
-    string key = mon->store->combine_strings(full_prefix_name, ver);
-    return mon->store->get(get_service_name(), key, bl);
-  }
-  /**
-   * Get the latest full version number
-   *
-   * @returns A version number
-   */
-  version_t get_version_latest_full() {
-    string key = mon->store->combine_strings(full_prefix_name, full_latest_name);
-    return mon->store->get(get_service_name(), key);
-  }
-
-  /**
-   * Get a value from a given key.
-   *
-   * @param[in] key The key
-   * @param[out] bl The bufferlist to be populated with the value
-   */
-  int get_value(const string& key, bufferlist& bl) {
-    return mon->store->get(get_service_name(), key, bl);
-  }
-  /**
-   * Get an integer value from a given key.
-   *
-   * @param[in] key The key
-   */
-  version_t get_value(const string& key) {
-    return mon->store->get(get_service_name(), key);
-  }
-
-  /**
-   * @}
-   */
-  /**
-   * @}
-   */
-};
-
-#endif
-