Support pids_limit in HostConfig

docker/utils/utils.py

@@ -623,7 +623,7 @@ def create_host_config(binds=None, port_bindings=None, lxc_conf=None,
                        device_write_iops=None, oom_kill_disable=False,
                        shm_size=None, sysctls=None, version=None, tmpfs=None,
                        oom_score_adj=None, dns_opt=None, cpu_shares=None,
-                       cpuset_cpus=None, userns_mode=None):
+                       cpuset_cpus=None, userns_mode=None, pids_limit=None):
 
     host_config = {}
 
@@ -904,6 +904,13 @@ def create_host_config(binds=None, port_bindings=None, lxc_conf=None,
             raise host_config_value_error("userns_mode", userns_mode)
         host_config['UsernsMode'] = userns_mode
 
+    if pids_limit:
+        if not isinstance(pids_limit, int):
+            raise host_config_type_error('pids_limit', pids_limit, 'int')
+        if version_lt(version, '1.23'):
+            raise host_config_version_error('pids_limit', '1.23')
+        host_config["PidsLimit"] = pids_limit
+
     return host_config
 
 

docs/hostconfig.md

@@ -111,11 +111,12 @@ for example:
   CPU period.
 * cpu_shares (int): CPU shares (relative weight)
 * cpuset_cpus (str): CPUs in which to allow execution (0-3, 0,1)
-* blkio_weight: Block IO weight (relative weight), accepts a weight value between 10 and 1000.
+* blkio_weight: Block IO weight (relative weight), accepts a weight value
+  between 10 and 1000.
 * blkio_weight_device: Block IO weight (relative device weight) in the form of:
   `[{"Path": "device_path", "Weight": weight}]`
-* device_read_bps: Limit read rate (bytes per second) from a device in the form of:
-  `[{"Path": "device_path", "Rate": rate}]`
+* device_read_bps: Limit read rate (bytes per second) from a device in the
+  form of: `[{"Path": "device_path", "Rate": rate}]`
 * device_write_bps: Limit write rate (bytes per second) from a device.
 * device_read_iops: Limit read rate (IO per second) from a device.
 * device_write_iops: Limit write rate (IO per second) from a device.
@@ -128,6 +129,7 @@ for example:
 * sysctls (dict): Kernel parameters to set in the container.
 * userns_mode (str): Sets the user namespace mode for the container when user
   namespace remapping option is enabled. Supported values are: `host`
+* pids_limit (int): Tune a container’s pids limit. Set -1 for unlimited.
 
 **Returns** (dict) HostConfig dictionary
 

tests/unit/utils_test.py

@@ -185,6 +185,15 @@ def test_create_host_config_with_kernel_memory(self):
             InvalidVersion, lambda: create_host_config(
                 version='1.20', kernel_memory=67108864))
 
+    def test_create_host_config_with_pids_limit(self):
+        config = create_host_config(version='1.23', pids_limit=1024)
+        self.assertEqual(config.get('PidsLimit'), 1024)
+
+        with pytest.raises(InvalidVersion):
+            create_host_config(version='1.22', pids_limit=1024)
+        with pytest.raises(TypeError):
+            create_host_config(version='1.22', pids_limit='1024')
+
 
 class UlimitTest(base.BaseTestCase):
     def test_create_host_config_dict_ulimit(self):