Beispiel #1
0
def import_to_db(reactor, key_type, value_type, input_format, input_file, etcd_address, dry_run,
                 dry_output, verbosity):
    db_current = yield get_all_keys(reactor, key_type, value_type, etcd_address)
    db_import = yield get_input_content(input_format, input_file, value_type)
    db_diff = yield get_db_diff(db_current, db_import, key_type, value_type)

    transaction = []

    if dry_run:
        pretty_print(db_diff, key_type, value_type, dry_output)
    else:
        for k, v in db_diff['to_update'].items():
            if not isinstance(k, bytes):
                k = k.encode()
            if not isinstance(v, bytes):
                v = v.encode()
            transaction.append(OpSet(k, v))

        for key in db_diff['to_delete']:
            if not isinstance(key, bytes):
                key = key.encode()
            transaction.append(OpDel(key))

        etcd = Client(reactor, etcd_address)
        yield etcd.submit(Transaction(success=transaction))
        if verbosity == 'verbose':
            pretty_print(db_diff, key_type, value_type, dry_output)
        elif verbosity == 'compact':
            print('{} updated.'.format(len(db_diff['to_update'])))
            print('{} deleted.'.format(len(db_diff['to_delete'])))
class EtcdClient(KVClient):

    def __init__(self, kv_host, kv_port):
        KVClient.__init__(self, kv_host, kv_port)
        self.url = u'http://' + kv_host + u':' + str(kv_port)
        self.client = Client(reactor, self.url)

    @inlineCallbacks
    def watch(self, key, key_change_callback, timeout=DEFAULT_TIMEOUT):
        self.key_watches[key] = key_change_callback
        result = yield self._op_with_retry('WATCH', key, None, timeout, callback=self.key_changed)
        returnValue(result)

    def key_changed(self, kv):
        key = kv.key
        value = kv.value
        log.debug('key-changed', key=key, value=value)
        # Notify client of key change event
        if value is not None:
            evt = Event(Event.PUT, key, value)
        else:
            evt = Event(Event.DELETE, key, None)
        if key in self.key_watches:
            self.key_watches[key](evt)

    def close_watch(self, key, timeout=DEFAULT_TIMEOUT):
        log.debug('close-watch', key=key)
        if key in self.key_watches:
            self.key_watches.pop(key)

    @inlineCallbacks
    def _op_with_retry(self, operation, key, value, timeout, *args, **kw):
        log.debug('kv-op', operation=operation, key=key, timeout=timeout, args=args, kw=kw)
        err = None
        result = None
        if type(key) == str:
            key = bytes(key)
        if value is not None:
           value = bytes(value)
        while True:
            try:
                if operation == 'GET':
                    result = yield self._get(key)
                elif operation == 'LIST':
                    result, err = yield self._list(key)
                elif operation == 'PUT':
                    # Put returns an object of type Revision
                    result = yield self.client.set(key, value, **kw)
                elif operation == 'DELETE':
                    # Delete returns an object of type Deleted
                    result = yield self.client.delete(key)
                elif operation == 'RESERVE':
                    result, err = yield self._reserve(key, value, **kw)
                elif operation == 'RENEW':
                    result, err = yield self._renew_reservation(key)
                elif operation == 'RELEASE':
                    result, err = yield self._release_reservation(key)
                elif operation == 'RELEASE-ALL':
                    err = yield self._release_all_reservations()
                elif operation == 'WATCH':
                    for name, val in kw.items():
                        if name == 'callback':
                            callback = val
                            break
                    result = self.client.watch([KeySet(key, prefix=True)], callback)
                self._clear_backoff()
                break
            except ConnectionRefusedError as ex:
                log.error('comms-exception', ex=ex)
                yield self._backoff('etcd-not-up')
            except Exception as ex:
                log.error('etcd-exception', ex=ex)
                err = ex

            if timeout > 0 and self.retry_time > timeout:
                err = 'operation-timed-out'
            if err is not None:
                self._clear_backoff()
                break

        returnValue((result, err))

    @inlineCallbacks
    def _get(self, key):
        kvp = None
        resp = yield self.client.get(key)
        if resp.kvs is not None and len(resp.kvs) == 1:
            kv = resp.kvs[0]
            kvp = KVPair(kv.key, kv.value, kv.mod_revision)
        returnValue(kvp)

    @inlineCallbacks
    def _list(self, key):
        err = None
        list = []
        resp = yield self.client.get(KeySet(key, prefix=True))
        if resp.kvs is not None and len(resp.kvs) > 0:
            for kv in resp.kvs:
                list.append(KVPair(kv.key, kv.value, kv.mod_revision))
        returnValue((list, err))

    @inlineCallbacks
    def _reserve(self, key, value, **kw):
        for name, val in kw.items():
            if name == 'ttl':
                ttl = val
                break
        reserved = False
        err = 'reservation-failed'
        owner = None

        # Create a lease
        lease = yield self.client.lease(ttl)

        # Create a transaction
        txn = Transaction(
            compare=[ CompVersion(key, '==', 0) ],
            success=[ OpSet(key, bytes(value), lease=lease) ],
            failure=[ OpGet(key) ]
        )
        newly_acquired = False
        try:
            result = yield self.client.submit(txn)
        except Failed as failed:
            log.debug('key-already-present', key=key)
            if len(failed.responses) > 0:
                response = failed.responses[0]
                if response.kvs is not None and len(response.kvs) > 0:
                    kv = response.kvs[0]
                    log.debug('key-already-present', value=kv.value)
                    if kv.value == value:
                        reserved = True
                        log.debug('key-already-reserved', key = kv.key, value=kv.value)
        else:
            newly_acquired = True
            log.debug('key-was-absent', key=key, result=result)

        # Check if reservation succeeded
        resp = yield self.client.get(key)
        if resp.kvs is not None and len(resp.kvs) == 1:
            owner = resp.kvs[0].value
            if owner == value:
                if newly_acquired:
                    log.debug('key-reserved', key=key, value=value, ttl=ttl,
                             lease_id=lease.lease_id)
                    reserved = True
                    # Add key to reservation list
                    self.key_reservations[key] = lease
                else:
                    log.debug("reservation-still-held")
            else:
                log.debug('reservation-held-by-another', value=owner)

        if reserved:
            err = None
        returnValue((owner, err))

    @inlineCallbacks
    def _renew_reservation(self, key):
        result = None
        err = None
        if key not in self.key_reservations:
            err = 'key-not-reserved'
        else:
            lease = self.key_reservations[key]
            # A successfully refreshed lease returns an object of type Header
            result = yield lease.refresh()
        if result is None:
            err = 'lease-refresh-failed'
        returnValue((result, err))

    @inlineCallbacks
    def _release_reservation(self, key):
        err = None
        if key not in self.key_reservations:
            err = 'key-not-reserved'
        else:
            lease = self.key_reservations[key]
            time_left = yield lease.remaining()
            # A successfully revoked lease returns an object of type Header
            log.debug('release-reservation', key=key, lease_id=lease.lease_id,
                      time_left_in_secs=time_left)
            result = yield lease.revoke()
            if result is None:
                err = 'lease-revoke-failed'
            self.key_reservations.pop(key)
        returnValue((result, err))

    @inlineCallbacks
    def _release_all_reservations(self):
        err = None
        keys_to_delete = []
        for key in self.key_reservations:
            lease = self.key_reservations[key]
            time_left = yield lease.remaining()
            # A successfully revoked lease returns an object of type Header
            log.debug('release-reservation', key=key, lease_id=lease.lease_id,
                      time_left_in_secs=time_left)
            result = yield lease.revoke()
            if result is None:
                err = 'lease-revoke-failed'
                log.debug('lease-revoke', result=result)
            keys_to_delete.append(key)
        for key in keys_to_delete:
            self.key_reservations.pop(key)
        returnValue(err)
Beispiel #3
0
def main(reactor):

    etcd = Client(reactor)

    #
    # Example 1
    #
    for val in [b'val1', b'val2']:

        yield etcd.set(b'test1', val)

        txn = Transaction(
            compare=[
                # compute conjunction of all terms to
                # determine "success" vs "failure"
                CompValue(b'test1', '==', b'val1')
            ],
            success=[
                # if true ("success"), run these ops
                OpSet(b'test1', b'val2'),
                OpSet(b'test2', b'success')
            ],
            failure=[
                # if not true ("failure"), run these ops
                OpSet(b'test2', b'failure'),
                OpGet(b'test1')
            ])

        try:
            result = yield etcd.submit(txn)
        except Failed as failed:
            print('transaction FAILED:')
            for response in failed.responses:
                print(response)
        else:
            print('transaction SUCCESS:')
            for response in result.responses:
                print(response)

        for key in [b'test1', b'test2']:
            value = yield etcd.get(key)
            print('{}: {}'.format(key, value))

    #
    # Example 2
    #
    rev = yield etcd.set(b'mykey1', os.urandom(8))
    print(rev)

    result = yield etcd.get(b'mykey1')
    kv = result.kvs[0]
    print(kv)

    for version in [kv.version, kv.version - 1]:
        txn = Transaction(
            compare=[
                # value equality comparison
                CompValue(b'mykey1', '==', kv.value),

                # version, and different comparison operators
                CompVersion(b'mykey1', '==', version),
                CompVersion(b'mykey1', '!=', version + 1),
                CompVersion(b'mykey1', '<', version + 1),
                CompVersion(b'mykey1', '>', version - 1),

                # created revision comparison
                CompCreated(b'mykey1', '==', kv.create_revision),

                # modified revision comparison
                CompModified(b'mykey1', '==', kv.mod_revision),
            ],
            success=[
                OpSet(b'mykey2', b'success'),
                OpSet(b'mykey3', os.urandom(8))
            ],
            failure=[
                OpSet(b'mykey2', b'failure'),
                OpSet(b'mykey3', os.urandom(8))
            ])

        try:
            result = yield etcd.submit(txn)
        except Failed as failed:
            print('transaction FAILED:')
            for response in failed.responses:
                print(response)
        else:
            print('transaction SUCCESS:')
            for response in result.responses:
                print(response)

        result = yield etcd.get(KeySet(b'mykey2', b'mykey4'))
        for kv in result.kvs:
            print(kv)