Merge pull request #916 from docker/container_update_feature

Support for container limits update

docker/api/container.py

@@ -398,6 +398,39 @@ class ContainerApiMixin(object):
         res = self._post(url)
         self._raise_for_status(res)
 
+    @utils.minimum_version('1.22')
+    @utils.check_resource
+    def update_container(
+        self, container, blkio_weight=None, cpu_period=None, cpu_quota=None,
+        cpu_shares=None, cpuset_cpus=None, cpuset_mems=None, mem_limit=None,
+        mem_reservation=None, memswap_limit=None, kernel_memory=None
+    ):
+        url = self._url('/containers/{0}/update', container)
+        data = {}
+        if blkio_weight:
+            data['BlkioWeight'] = blkio_weight
+        if cpu_period:
+            data['CpuPeriod'] = cpu_period
+        if cpu_shares:
+            data['CpuShares'] = cpu_shares
+        if cpu_quota:
+            data['CpuQuota'] = cpu_quota
+        if cpuset_cpus:
+            data['CpusetCpus'] = cpuset_cpus
+        if cpuset_mems:
+            data['CpusetMems'] = cpuset_mems
+        if mem_limit:
+            data['Memory'] = utils.parse_bytes(mem_limit)
+        if mem_reservation:
+            data['MemoryReservation'] = utils.parse_bytes(mem_reservation)
+        if memswap_limit:
+            data['MemorySwap'] = utils.parse_bytes(memswap_limit)
+        if kernel_memory:
+            data['KernelMemory'] = utils.parse_bytes(kernel_memory)
+
+        res = self._post_json(url, data=data)
+        return self._result(res, True)
+
     @utils.check_resource
     def wait(self, container, timeout=None):
         url = self._url("/containers/{0}/wait", container)

docker/utils/utils.py

@@ -518,41 +518,43 @@ def longint(n):
 
 
 def parse_bytes(s):
+    if isinstance(s, six.integer_types + (float,)):
+        return s
     if len(s) == 0:
-        s = 0
-    else:
-        if s[-2:-1].isalpha() and s[-1].isalpha():
-            if s[-1] == "b" or s[-1] == "B":
-                s = s[:-1]
-        units = BYTE_UNITS
-        suffix = s[-1].lower()
-
-        # Check if the variable is a string representation of an int
-        # without a units part. Assuming that the units are bytes.
-        if suffix.isdigit():
-            digits_part = s
-            suffix = 'b'
-        else:
-            digits_part = s[:-1]
+        return 0
 
-        if suffix in units.keys() or suffix.isdigit():
-            try:
-                digits = longint(digits_part)
-            except ValueError:
-                raise errors.DockerException(
-                    'Failed converting the string value for memory ({0}) to'
-                    ' an integer.'.format(digits_part)
-                )
+    if s[-2:-1].isalpha() and s[-1].isalpha():
+        if s[-1] == "b" or s[-1] == "B":
+            s = s[:-1]
+    units = BYTE_UNITS
+    suffix = s[-1].lower()
+
+    # Check if the variable is a string representation of an int
+    # without a units part. Assuming that the units are bytes.
+    if suffix.isdigit():
+        digits_part = s
+        suffix = 'b'
+    else:
+        digits_part = s[:-1]
 
-            # Reconvert to long for the final result
-            s = longint(digits * units[suffix])
-        else:
+    if suffix in units.keys() or suffix.isdigit():
+        try:
+            digits = longint(digits_part)
+        except ValueError:
             raise errors.DockerException(
-                'The specified value for memory ({0}) should specify the'
-                ' units. The postfix should be one of the `b` `k` `m` `g`'
-                ' characters'.format(s)
+                'Failed converting the string value for memory ({0}) to'
+                ' an integer.'.format(digits_part)
             )
 
+        # Reconvert to long for the final result
+        s = longint(digits * units[suffix])
+    else:
+        raise errors.DockerException(
+            'The specified value for memory ({0}) should specify the'
+            ' units. The postfix should be one of the `b` `k` `m` `g`'
+            ' characters'.format(s)
+        )
+
     return s
 
 
@@ -594,16 +596,10 @@ def create_host_config(binds=None, port_bindings=None, lxc_conf=None,
         version = constants.DEFAULT_DOCKER_API_VERSION
 
     if mem_limit is not None:
-        if isinstance(mem_limit, six.string_types):
-            mem_limit = parse_bytes(mem_limit)
-
-        host_config['Memory'] = mem_limit
+        host_config['Memory'] = parse_bytes(mem_limit)
 
     if memswap_limit is not None:
-        if isinstance(memswap_limit, six.string_types):
-            memswap_limit = parse_bytes(memswap_limit)
-
-        host_config['MemorySwap'] = memswap_limit
+        host_config['MemorySwap'] = parse_bytes(memswap_limit)
 
     if mem_swappiness is not None:
         if version_lt(version, '1.20'):
@@ -878,9 +874,9 @@ def create_container_config(
     if isinstance(labels, list):
         labels = dict((lbl, six.text_type('')) for lbl in labels)
 
-    if isinstance(mem_limit, six.string_types):
+    if mem_limit is not None:
         mem_limit = parse_bytes(mem_limit)
-    if isinstance(memswap_limit, six.string_types):
+    if memswap_limit is not None:
         memswap_limit = parse_bytes(memswap_limit)
 
     if isinstance(ports, list):

docs/api.md

@@ -998,12 +998,32 @@ Display the running processes of a container.
 
 ## unpause
 
-Unpauses all processes within a container.
+Unpause all processes within a container.
 
 **Params**:
 
 * container (str): The container to unpause
 
+## update_container
+
+Update resource configs of one or more containers.
+
+**Params**:
+
+* container (str): The container to inspect
+* blkio_weight (int): Block IO (relative weight), between 10 and 1000
+* cpu_period (int): Limit CPU CFS (Completely Fair Scheduler) period
+* cpu_quota (int): Limit CPU CFS (Completely Fair Scheduler) quota
+* cpu_shares (int): CPU shares (relative weight)
+* cpuset_cpus (str): CPUs in which to allow execution
+* cpuset_mems (str): MEMs in which to allow execution
+* mem_limit (int or str): Memory limit
+* mem_reservation (int or str): Memory soft limit
+* memswap_limit (int or str): Total memory (memory + swap), -1 to disable swap
+* kernel_memory (int or str): Kernel memory limit
+
+**Returns** (dict): Dictionary containing a `Warnings` key.
+
 ## version
 
 Nearly identical to the `docker version` command.

tests/integration/container_test.py

@@ -1044,3 +1044,21 @@ class GetContainerStatsTest(helpers.BaseTestCase):
                 for key in ['read', 'network', 'precpu_stats', 'cpu_stats',
                             'memory_stats', 'blkio_stats']:
                     self.assertIn(key, chunk)
+
+
+class ContainerUpdateTest(helpers.BaseTestCase):
+    @requires_api_version('1.22')
+    def test_update_container(self):
+        old_mem_limit = 400 * 1024 * 1024
+        new_mem_limit = 300 * 1024 * 1024
+        container = self.client.create_container(
+            BUSYBOX, 'top', host_config=self.client.create_host_config(
+                mem_limit=old_mem_limit
+            ), cpu_shares=102
+        )
+        self.tmp_containers.append(container)
+        self.client.start(container)
+        self.client.update_container(container, mem_limit=new_mem_limit)
+        inspect_data = self.client.inspect_container(container)
+        self.assertEqual(inspect_data['HostConfig']['Memory'], new_mem_limit)
+        self.assertEqual(inspect_data['HostConfig']['CpuShares'], 102)

tests/unit/container_test.py

@@ -1452,3 +1452,21 @@ class ContainerTest(DockerClientTest):
             params={'ps_args': 'waux'},
             timeout=DEFAULT_TIMEOUT_SECONDS
         )
+
+    @requires_api_version('1.22')
+    def test_container_update(self):
+        self.client.update_container(
+            fake_api.FAKE_CONTAINER_ID, mem_limit='2k', cpu_shares=124,
+            blkio_weight=345
+        )
+        args = fake_request.call_args
+        self.assertEqual(
+            args[0][1], url_prefix + 'containers/3cc2351ab11b/update'
+        )
+        self.assertEqual(
+            json.loads(args[1]['data']),
+            {'Memory': 2 * 1024, 'CpuShares': 124, 'BlkioWeight': 345}
+        )
+        self.assertEqual(
+            args[1]['headers']['Content-Type'], 'application/json'
+        )

tests/unit/fake_api.py

@@ -441,6 +441,11 @@ def get_fake_volume():
 def fake_remove_volume():
     return 204, None
 
+
+def post_fake_update_container():
+    return 200, {'Warnings': []}
+
+
 # Maps real api url to fake response callback
 prefix = 'http+docker://localunixsocket'
 fake_responses = {
@@ -478,6 +483,8 @@ fake_responses = {
     get_fake_diff,
     '{1}/{0}/containers/3cc2351ab11b/export'.format(CURRENT_VERSION, prefix):
     get_fake_export,
+    '{1}/{0}/containers/3cc2351ab11b/update'.format(CURRENT_VERSION, prefix):
+    post_fake_update_container,
     '{1}/{0}/containers/3cc2351ab11b/exec'.format(CURRENT_VERSION, prefix):
     post_fake_exec_create,
     '{1}/{0}/exec/d5d177f121dc/start'.format(CURRENT_VERSION, prefix):