New Features + Refactoring

1. User can now use image name instead of image uuid when creation vm.
   For Example, now user can create an alpine vm using the following
   command
   ```shell
   ucloud-cli vm create --vm-name myvm --cpu 2 --ram '2GB' \
       --os-ssd '10GB' --image images:alpine
   ```
2. Instead of directly running code, code is now placed under a function
   main and is called using the following code
   ```python
   if __name__ == "__main__":
       main()
   ```
3. Multiprocess (Process) is used instead of threading (Thread) to update
   heart beat of host.
4. IP Address of vm is included in vm's status which is retrieved by the
   following command
   ```shell
   ucloud-cli vm status --vm-name myvm
   ```

.gitignore

@@ -2,4 +2,6 @@
 .vscode
 .env
 
+__pycache__
+
 */log.txt

Pipfile.lock

@@ -83,10 +83,12 @@
                 "sha256:7cfcfda59ef1f95b9f729c56fe8a4041899f96b72685d36ef16a3440a0f85da8",
                 "sha256:819f8d5197c2684524637f940445c06e003c4a541f9983fd30d6deaa2a5487d8",
                 "sha256:825ecffd9574557590e3225560a8a9d751f6ffe4a49e3c40918c9969b93395fa",
+                "sha256:8a2bcae2258d00fcfc96a9bde4a6177bc4274fe033f79311c5dd3d3148c26518",
                 "sha256:9009e917d8f5ef780c2626e29b6bc126f4cb2a4d43ca67aa2b40f2a5d6385e78",
                 "sha256:9c77564a51d4d914ed5af096cd9843d90c45b784b511723bd46a8a9d09cf16fc",
                 "sha256:a19089fa74ed19c4fe96502a291cfdb89223a9705b1d73b3005df4256976142e",
                 "sha256:a40ed527bffa2b7ebe07acc5a3f782da072e262ca994b4f2085100b5a444bbb2",
+                "sha256:b8f09f21544b9899defb09afbdaeb200e6a87a2b8e604892940044cf94444644",
                 "sha256:bb75ba21d5716abc41af16eac1145ab2e471deedde1f22c6f99bd9f995504df0",
                 "sha256:e22a00c0c81ffcecaf07c2bfb3672fa372c50e2bd1024ffee0da191c1b27fc71",
                 "sha256:e55b5a746fb77f10c83e8af081979351722f6ea48facea79d470b3731c7b2891",
@@ -293,7 +295,6 @@
         },
         "pycparser": {
             "hashes": [
-                "sha256:9d97450dc26e1d2581c18881d8d1c0a92e84c9ac074961e3dc66e70d745a0643",
                 "sha256:a988718abfad80b6b157acce7bf130a30876d27603738ac39f140993246b25b3"
             ],
             "version": "==2.19"
@@ -375,15 +376,15 @@
         },
         "tenacity": {
             "hashes": [
-                "sha256:6a7511a59145c2e319b7d04ddd93c12d48cc3d3c8fa42c2846d33a620ee91f57",
+                "sha256:3a916e734559f1baa2cab965ee00061540c41db71c3bf25375b81540a19758fc",
-                "sha256:a4eb168dbf55ed2cae27e7c6b2bd48ab54dabaf294177d998330cf59f294c112"
+                "sha256:e664bd94f088b17f46da33255ae33911ca6a0fe04b156d334b601a4ef66d3c5f"
             ],
-            "version": "==5.1.1"
+            "version": "==5.1.5"
         },
         "ucloud-common": {
             "editable": true,
             "git": "https://code.ungleich.ch/ucloud/ucloud_common.git",
-            "ref": "9f229eae27f9007e9c6c1021d3d5b12452863763"
+            "ref": "eba92e5d6723093a3cc2999ae1f5c284e65dc809"
         },
         "urllib3": {
             "hashes": [
@@ -509,26 +510,29 @@
         },
         "lazy-object-proxy": {
             "hashes": [
-                "sha256:02b260c8deb80db09325b99edf62ae344ce9bc64d68b7a634410b8e9a568edbf",
+                "sha256:0c4b206227a8097f05c4dbdd323c50edf81f15db3b8dc064d08c62d37e1a504d",
-                "sha256:18f9c401083a4ba6e162355873f906315332ea7035803d0fd8166051e3d402e3",
+                "sha256:194d092e6f246b906e8f70884e620e459fc54db3259e60cf69a4d66c3fda3449",
-                "sha256:1f2c6209a8917c525c1e2b55a716135ca4658a3042b5122d4e3413a4030c26ce",
+                "sha256:1be7e4c9f96948003609aa6c974ae59830a6baecc5376c25c92d7d697e684c08",
-                "sha256:2f06d97f0ca0f414f6b707c974aaf8829c2292c1c497642f63824119d770226f",
+                "sha256:4677f594e474c91da97f489fea5b7daa17b5517190899cf213697e48d3902f5a",
-                "sha256:616c94f8176808f4018b39f9638080ed86f96b55370b5a9463b2ee5c926f6c5f",
+                "sha256:48dab84ebd4831077b150572aec802f303117c8cc5c871e182447281ebf3ac50",
-                "sha256:63b91e30ef47ef68a30f0c3c278fbfe9822319c15f34b7538a829515b84ca2a0",
+                "sha256:5541cada25cd173702dbd99f8e22434105456314462326f06dba3e180f203dfd",
-                "sha256:77b454f03860b844f758c5d5c6e5f18d27de899a3db367f4af06bec2e6013a8e",
+                "sha256:59f79fef100b09564bc2df42ea2d8d21a64fdcda64979c0fa3db7bdaabaf6239",
-                "sha256:83fe27ba321e4cfac466178606147d3c0aa18e8087507caec78ed5a966a64905",
+                "sha256:8d859b89baf8ef7f8bc6b00aa20316483d67f0b1cbf422f5b4dc56701c8f2ffb",
-                "sha256:84742532d39f72df959d237912344d8a1764c2d03fe58beba96a87bfa11a76d8",
+                "sha256:9254f4358b9b541e3441b007a0ea0764b9d056afdeafc1a5569eee1cc6c1b9ea",
-                "sha256:874ebf3caaf55a020aeb08acead813baf5a305927a71ce88c9377970fe7ad3c2",
+                "sha256:9651375199045a358eb6741df3e02a651e0330be090b3bc79f6d0de31a80ec3e",
-                "sha256:9f5caf2c7436d44f3cec97c2fa7791f8a675170badbfa86e1992ca1b84c37009",
+                "sha256:97bb5884f6f1cdce0099f86b907aa41c970c3c672ac8b9c8352789e103cf3156",
-                "sha256:a0c8758d01fcdfe7ae8e4b4017b13552efa7f1197dd7358dc9da0576f9d0328a",
+                "sha256:9b15f3f4c0f35727d3a0fba4b770b3c4ebbb1fa907dbcc046a1d2799f3edd142",
-                "sha256:a4def978d9d28cda2d960c279318d46b327632686d82b4917516c36d4c274512",
+                "sha256:a2238e9d1bb71a56cd710611a1614d1194dc10a175c1e08d75e1a7bcc250d442",
-                "sha256:ad4f4be843dace866af5fc142509e9b9817ca0c59342fdb176ab6ad552c927f5",
+                "sha256:a6ae12d08c0bf9909ce12385803a543bfe99b95fe01e752536a60af2b7797c62",
-                "sha256:ae33dd198f772f714420c5ab698ff05ff900150486c648d29951e9c70694338e",
+                "sha256:ca0a928a3ddbc5725be2dd1cf895ec0a254798915fb3a36af0964a0a4149e3db",
-                "sha256:b4a2b782b8a8c5522ad35c93e04d60e2ba7f7dcb9271ec8e8c3e08239be6c7b4",
+                "sha256:cb2c7c57005a6804ab66f106ceb8482da55f5314b7fcb06551db1edae4ad1531",
-                "sha256:c462eb33f6abca3b34cdedbe84d761f31a60b814e173b98ede3c81bb48967c4f",
+                "sha256:d74bb8693bf9cf75ac3b47a54d716bbb1a92648d5f781fc799347cfc95952383",
-                "sha256:fd135b8d35dfdcdb984828c84d695937e58cc5f49e1c854eb311c4d6aa03f4f1"
+                "sha256:d945239a5639b3ff35b70a88c5f2f491913eb94871780ebfabb2568bd58afc5a",
+                "sha256:eba7011090323c1dadf18b3b689845fd96a61ba0a1dfbd7f24b921398affc357",
+                "sha256:efa1909120ce98bbb3777e8b6f92237f5d5c8ea6758efea36a473e1d38f7d3e4",
+                "sha256:f3900e8a5de27447acbf900b4750b0ddfd7ec1ea7fbaf11dfa911141bc522af0"
             ],
-            "version": "==1.4.2"
+            "version": "==1.4.3"
         },
         "mccabe": {
             "hashes": [
@@ -743,11 +747,11 @@
         },
         "typing-extensions": {
             "hashes": [
-                "sha256:2ed632b30bb54fc3941c382decfd0ee4148f5c591651c9272473fea2c6397d95",
+                "sha256:091ecc894d5e908ac75209f10d5b4f118fbdb2eb1ede6a63544054bb1edb41f2",
-                "sha256:b1edbbf0652660e32ae780ac9433f4231e7339c7f9a8057d0f042fcbcea49b87",
+                "sha256:910f4656f54de5993ad9304959ce9bb903f90aadc7c67a0bef07e678014e892d",
-                "sha256:d8179012ec2c620d3791ca6fe2bf7979d979acdbef1fca0bc56b37411db682ed"
+                "sha256:cf8b63fedea4d89bab840ecbb93e75578af28f76f66c35889bd7065f5af88575"
             ],
-            "version": "==3.7.4"
+            "version": "==3.7.4.1"
         },
         "urllib3": {
             "hashes": [

TODO.md

@@ -3,4 +3,3 @@
 - Check for `etcd3.exceptions.ConnectionFailedError` when calling some etcd operation to
   avoid crashing whole application
 - Throw KeyError instead of returning None when some key is not found in etcd
-- Specify image format when using qemu-img when creating virtual machine

api/helper.py

@@ -1,9 +1,12 @@
 import binascii
 import requests
+import random
+import subprocess as sp
+import ipaddress
 
 from decouple import config
 from pyotp import TOTP
-from config import VM_POOL
+from config import VM_POOL, etcd_client, IMAGE_PREFIX
 
 
 def check_otp(name, realm, token):
@@ -47,7 +50,47 @@ def resolve_vm_name(name, owner):
 
     return None
 
-import random
+
+def resolve_image_name(name, etcd_client):
+    """Return image uuid given its name and its store
+       
+       * If the provided name is not in correct format
+         i.e {store_name}:{image_name} return ValueError
+       * If no such image found then return KeyError
+
+    """
+
+    seperator = ":"
+    
+    # Ensure, user/program passed valid name that is of type string
+    try:
+        store_name_and_image_name = name.split(seperator)
+
+        """
+        Examples, where it would work and where it would raise exception
+        "images:alpine" --> ["images", "alpine"]
+        
+        "images" --> ["images"] it would raise Exception as non enough value to unpack
+        
+        "images:alpine:meow" --> ["images", "alpine", "meow"] it would raise Exception
+                                                              as too many values to unpack
+        """
+        store_name, image_name = store_name_and_image_name
+    except Exception:
+        raise ValueError("Image name not in correct format i.e {store_name}:{image_name}")
+
+    images = etcd_client.get_prefix(IMAGE_PREFIX, value_in_json=True)
+
+    # Try to find image with name == image_name and store_name == store_name
+    try:
+        image = next(filter(lambda im: im.value['name'] == image_name \
+                                       and im.value['store_name'] == store_name, images))
+    except StopIteration:
+        raise KeyError("No image with name {} found.".format(name))
+    else:
+        image_uuid = image.key.split('/')[-1]
+    
+    return image_uuid
 
 def random_bytes(num=6):
     return [random.randrange(256) for _ in range(num)]
@@ -68,3 +111,32 @@ def generate_mac(uaa=False, multicast=False, oui=None, separator=':', byte_fmt='
         else:
             mac[0] |= 1 << 1 # set bit 1
     return separator.join(byte_fmt % b for b in mac)
+
+def get_ip_addr(mac_address, device):
+    """Return IP address of a device provided its mac address / link local address
+       and the device with which it is connected.
+       
+       For Example, if we call get_ip_addr(mac_address="52:54:00:12:34:56", device="br0")
+       the following two scenarios can happen
+       1. It would return None if we can't be able to find device whose mac_address is equal
+          to the arg:mac_address or the mentioned arg:device does not exists or the ip address
+          we found is local.
+       2. It would return ip_address of device whose mac_address is equal to arg:mac_address
+          and is connected/neighbor of arg:device       
+    """
+    try:
+        output = sp.check_output(['ip','-6','neigh', 'show', 'dev', device], stderr=sp.PIPE)
+    except sp.CalledProcessError:
+        return None
+    else:
+        result = []
+        output = output.strip().decode("utf-8")
+        output = output.split("\n")
+        for entry in output:
+            entry = entry.split()
+            if entry:
+                ip = ipaddress.ip_address(entry[0])
+                mac = entry[2]
+                if ip.is_global and mac_address == mac:
+                    result.append(ip)
+        return result

api/main.py

@@ -1,6 +1,9 @@
 import json
 import subprocess
 import os
+
+import schemas
+
 from uuid import uuid4
 
 from flask import Flask, request
@@ -9,7 +12,7 @@ from flask_restful import Resource, Api
 from ucloud_common.vm import VMStatus
 from ucloud_common.request import RequestEntry, RequestType
 
-from helper import generate_mac
+from helper import generate_mac, get_ip_addr
 
 from config import (
     etcd_client,
@@ -23,18 +26,6 @@ from config import (
     VM_POOL,
     HOST_POOL,
 )
-from schemas import (
-    CreateVMSchema,
-    VMStatusSchema,
-    CreateImageSchema,
-    VmActionSchema,
-    OTPSchema,
-    CreateHostSchema,
-    VmMigrationSchema,
-    AddSSHSchema,
-    RemoveSSHSchema,
-    GetSSHSchema
-)
 
 app = Flask(__name__)
 api = Api(app)
@@ -45,7 +36,7 @@ class CreateVM(Resource):
     def post():
         data = request.json
         print(data)
-        validator = CreateVMSchema(data)
+        validator = schemas.CreateVMSchema(data)
         if validator.is_valid():
             vm_uuid = uuid4().hex
             vm_key = os.path.join(VM_PREFIX, vm_uuid)
@@ -63,7 +54,7 @@ class CreateVM(Resource):
                 "specs": specs,
                 "hostname": "",
                 "status": "",
-                "image_uuid": data["image_uuid"],
+                "image_uuid": validator.image_uuid,
                 "log": [],
                 "vnc_socket": "",
                 "mac": str(generate_mac()),
@@ -85,10 +76,14 @@ class VmStatus(Resource):
     @staticmethod
     def get():
         data = request.json
-        validator = VMStatusSchema(data)
+        validator = schemas.VMStatusSchema(data)
         if validator.is_valid():
             vm = VM_POOL.get(os.path.join(VM_PREFIX, data["uuid"]))
-            return json.dumps(str(vm))
+            vm_value = vm.value.copy()
+            vm_value["ip"] = list(map(str, get_ip_addr(vm.mac, "br0")))
+            vm.value = vm_value
+            print(vm.value)
+            return vm.value
         else:
             return validator.get_errors(), 400
 
@@ -97,7 +92,7 @@ class CreateImage(Resource):
     @staticmethod
     def post():
         data = request.json
-        validator = CreateImageSchema(data)
+        validator = schemas.CreateImageSchema(data)
         if validator.is_valid():
             file_entry = etcd_client.get(os.path.join(FILE_PREFIX, data["uuid"]))
             file_entry_value = json.loads(file_entry.value)
@@ -121,10 +116,15 @@ class CreateImage(Resource):
 class ListPublicImages(Resource):
     @staticmethod
     def get():
-        images = etcd_client.get_prefix(IMAGE_PREFIX)
+        images = etcd_client.get_prefix(IMAGE_PREFIX, value_in_json=True)
         r = {}
+        r["images"] = []
         for image in images:
-            r[image.key.split("/")[-1]] = json.loads(image.value)
+            image_key = "{}:{}".format(image.value["store_name"], image.value["name"])
+            r["images"].append({
+                "name":image_key,
+                "status": image.value["status"]
+            })
         return r, 200
 
 
@@ -132,7 +132,7 @@ class VMAction(Resource):
     @staticmethod
     def post():
         data = request.json
-        validator = VmActionSchema(data)
+        validator = schemas.VmActionSchema(data)
 
         if validator.is_valid():
             vm_entry = VM_POOL.get(os.path.join(VM_PREFIX, data["uuid"]))
@@ -182,7 +182,7 @@ class VMMigration(Resource):
     @staticmethod
     def post():
         data = request.json
-        validator = VmMigrationSchema(data)
+        validator = schemas.VmMigrationSchema(data)
 
         if validator.is_valid():
             vm = VM_POOL.get(data["uuid"])
@@ -203,7 +203,7 @@ class ListUserVM(Resource):
     @staticmethod
     def get():
         data = request.json
-        validator = OTPSchema(data)
+        validator = schemas.OTPSchema(data)
 
         if validator.is_valid():
             vms = etcd_client.get_prefix(VM_PREFIX, value_in_json=True)
@@ -235,7 +235,7 @@ class ListUserFiles(Resource):
     @staticmethod
     def get():
         data = request.json
-        validator = OTPSchema(data)
+        validator = schemas.OTPSchema(data)
 
         if validator.is_valid():
             files = etcd_client.get_prefix(FILE_PREFIX, value_in_json=True)
@@ -257,7 +257,7 @@ class CreateHost(Resource):
     @staticmethod
     def post():
         data = request.json
-        validator = CreateHostSchema(data)
+        validator = schemas.CreateHostSchema(data)
         if validator.is_valid():
             host_key = os.path.join(HOST_PREFIX, uuid4().hex)
             host_entry = {
@@ -292,7 +292,7 @@ class GetSSHKeys(Resource):
     @staticmethod
     def get():
         data = request.json
-        validator = GetSSHSchema(data)
+        validator = schemas.GetSSHSchema(data)
         if validator.is_valid():
             if not validator.key_name.value:
 
@@ -321,7 +321,7 @@ class AddSSHKey(Resource):
     @staticmethod
     def post():
         data = request.json
-        validator = AddSSHSchema(data)
+        validator = schemas.AddSSHSchema(data)
         if validator.is_valid():
             
             # {user_prefix}/{realm}/{name}/key/{key_name}
@@ -342,7 +342,7 @@ class RemoveSSHKey(Resource):
     @staticmethod
     def get():
         data = request.json
-        validator = RemoveSSHSchema(data)
+        validator = schemas.RemoveSSHSchema(data)
         if validator.is_valid():
             
             # {user_prefix}/{realm}/{name}/key/{key_name}

api/schemas.py

@@ -18,6 +18,8 @@ import json
 import os
 import bitmath
 
+import helper
+
 from ucloud_common.host import HostPool, HostStatus
 from ucloud_common.vm import VmPool, VMStatus
 
@@ -207,22 +209,24 @@ class CreateVMSchema(OTPSchema):
         # Fields
         self.specs = Field("specs", dict, data.get("specs", KeyError))
         self.vm_name = Field("vm_name", str, data.get("vm_name", KeyError))
-        self.image_uuid = Field("image_uuid", str, data.get("image_uuid", KeyError))
+        self.image = Field("image", str, data.get("image", KeyError))
 
         # Validation
-        self.image_uuid.validation = self.image_uuid_validation
+        self.image.validation = self.image_validation
         self.vm_name.validation = self.vm_name_validation
         self.specs.validation = self.specs_validation
 
-        fields = [self.vm_name, self.image_uuid, self.specs]
+        fields = [self.vm_name, self.image, self.specs]
 
         super().__init__(data=data, fields=fields)
 
-    def image_uuid_validation(self):
+    def image_validation(self):
-        images = client.get_prefix(IMAGE_PREFIX)
+        try:
-
+            image_uuid = helper.resolve_image_name(self.image.value, client)
-        if self.image_uuid.value not in [i.key.split("/")[-1] for i in images]:
+        except Exception as e:
-            self.add_error("Image UUID not valid")
+            self.add_error(str(e))
+        else:
+            self.image_uuid = image_uuid
 
     def vm_name_validation(self):
         if resolve_vm_name(name=self.vm_name.value, owner=self.name.value):

filescanner/main.py

@@ -12,6 +12,7 @@ from uuid import uuid4
 
 
 def getxattr(file, attr):
+    """Get specified user extended attribute (arg:attr) of a file (arg:file)"""
     try:
         attr = "user." + attr
         value = sp.check_output(['getfattr', file,
@@ -24,25 +25,39 @@ def getxattr(file, attr):
     
     return value
 
+
 def setxattr(file, attr, value):
+    """Set specified user extended attribute (arg:attr) equal to (arg:value)
+       of a file (arg:file)"""
+
     attr = "user." + attr
     sp.check_output(['setfattr', file,
                         '--name', attr,
                         '--value', str(value)])
 
 
-def sha512sum(filename):
+def sha512sum(file: str):
-    _sum = hashlib.sha512()
+    """Use sha512sum utility to compute sha512 sum of arg:file
-    buffer_size = 2**16
        
-    with open(filename, "rb") as f:
+       IF arg:file does not exists:
-        while True:
+        raise FileNotFoundError exception
-            data = f.read(buffer_size)
+       ELSE IF sum successfully computer:
-            if not data:
+        return computed sha512 sum
-                break
+       ELSE:
-            _sum.update(data)
+        return None
-
+    """
-    return _sum.hexdigest()
+    if not isinstance(file, str): raise TypeError
+    try:
+        output = sp.check_output(["sha512sum", file], stderr=sp.PIPE)
+    except sp.CalledProcessError as e:
+        error = e.stderr.decode("utf-8")
+        if "No such file or directory" in error:
+            raise FileNotFoundError from None
+    else:
+        output = output.decode("utf-8").strip()
+        output = output.split(" ")
+        return output[0]
+    return None
 
 
 try:
@@ -53,7 +68,7 @@ except Exception as e:
     print('Make sure you have getfattr and setfattr available')
     exit(1)
 
-
+def main():
     BASE_DIR = config("BASE_DIR")
 
     FILE_PREFIX = config("FILE_PREFIX")
@@ -107,3 +122,7 @@ for file in untracked_files:
         # Insert Entry
         etcd_client.put(entry_key, entry_value, value_in_json=True)
         setxattr(file, "user.utracked", True)
+
+
+if __name__ == "__main__":
+    main()

host/config.py

@@ -16,7 +16,10 @@ logging.basicConfig(
     datefmt="%d-%b-%y %H:%M:%S",
 )
 
-etcd_client = Etcd3Wrapper(host=config("ETCD_URL"))
+etcd_wrapper_args = ()
+etcd_wrapper_kwargs = {"host": config("ETCD_URL")}
+
+etcd_client = Etcd3Wrapper(*etcd_wrapper_args, **etcd_wrapper_kwargs)
 
 HOST_PREFIX = config("HOST_PREFIX")
 VM_PREFIX = config("VM_PREFIX")

host/main.py

@@ -1,27 +1,32 @@
 import argparse
-import threading
+# import threading
 import time
 import os
 import sys
 import virtualmachine
+import multiprocessing as mp
 
 from ucloud_common.host import HostEntry
 from ucloud_common.request import RequestEntry, RequestType
 
 from config import (vm_pool, host_pool, request_pool,
                     etcd_client, logging, running_vms,
-                    REQUEST_PREFIX, WITHOUT_CEPH)
+                    etcd_wrapper_args, etcd_wrapper_kwargs,
+                    REQUEST_PREFIX, HOST_PREFIX,
+                    WITHOUT_CEPH, VM_DIR, HostPool)
+from etcd3_wrapper import Etcd3Wrapper
+import etcd3
 
+def update_heartbeat(host):
+    client = Etcd3Wrapper(*etcd_wrapper_args, **etcd_wrapper_kwargs)
+    host_pool = HostPool(client, HOST_PREFIX)
+    this_host = host_pool.get(host)
 
-def update_heartbeat(host: HostEntry):
     while True:
-        host.update_heartbeat()
+        this_host.update_heartbeat()
-        host_pool.put(host)
+        host_pool.put(this_host)
         time.sleep(10)
 
-        logging.info("Updated last heartbeat time %s", host.last_heartbeat)
-
-
 def maintenance(host):
     # To capture vm running according to running_vms list
 
@@ -66,14 +71,23 @@ def main():
     argparser.add_argument("hostname", help="Name of this host. e.g /v1/host/1")
     args = argparser.parse_args()
 
-    host = host_pool.get(args.hostname)
+    assert WITHOUT_CEPH and os.path.isdir(VM_DIR), (
-    if not host:
+        "You have set WITHOUT_CEPH to True. So, the vm directory mentioned" 
-        print("No Such Host")
+        " in .env file must exists. But, it don't." )
-        exit(1)
     
-    if WITHOUT_CEPH and not os.path.isdir("/var/vm"):
+    mp.set_start_method('spawn')
-        print("You have set WITHOUT_CEPH to True. So, the /var/vm must exists. But, it don't")
+    heartbeat_updating_process = mp.Process(target=update_heartbeat, args=(args.hostname,))
-        sys.exit(1)
+
+    host_pool = HostPool(etcd_client, HOST_PREFIX)
+    host = host_pool.get(args.hostname)
+    assert host, "No such host"
+
+    try:
+        heartbeat_updating_process.start()
+    except Exception as e:
+        logging.info("No Need To Go Further. Our heartbeat updating mechanism is not working")
+        logging.exception(e)
+        exit(-1)
 
     
     logging.info("%s Session Started %s", '*' * 5, '*' * 5)
@@ -86,13 +100,6 @@ def main():
     # update the heart beat in a predictive manner we start Heart
     # beat updating mechanism in separated thread
 
-    heartbeat_updating_thread = threading.Thread(target=update_heartbeat, args=(host,))
-    try:
-        heartbeat_updating_thread.start()
-    except Exception as e:
-        logging.info("No Need To Go Further. Our heartbeat updating mechanism is not working")
-        logging.exception(e)
-        exit(-1)
 
     for events_iterator in [
         etcd_client.get_prefix(REQUEST_PREFIX, value_in_json=True),
@@ -134,4 +141,6 @@ def main():
                 logging.info("Running VMs %s", running_vms)
 
 
+if __name__ == "__main__":
     main()
+   

imagescanner/main.py

@@ -19,6 +19,8 @@ def qemu_img_type(path):
         qemu_img_info = json.loads(qemu_img_info.decode("utf-8"))
         return qemu_img_info["format"]
 
+
+def main():
     # If you are using WITHOUT_CEPH FLAG in .env
     # then please make sure that IMAGE_DIR directory
     # exists otherwise this script would fail
@@ -106,3 +108,7 @@ for image in images_to_be_created:
             os.remove("image.raw")
         except Exception:
             pass
+
+
+if __name__ == "__main__":
+    main()

metadata/config.py

@@ -15,6 +15,7 @@ logging.basicConfig(
 
 
 VM_PREFIX = config("VM_PREFIX")
+USER_PREFIX = config("USER_PREFIX")
 
 etcd_client = Etcd3Wrapper(host=config("ETCD_URL"))
 

metadata/main.py

@@ -1,6 +1,8 @@
+import os
+
 from flask import Flask, request
 from flask_restful import Resource, Api
-from config import etcd_client, VM_POOL
+from config import etcd_client, VM_POOL, USER_PREFIX
 
 app = Flask(__name__)
 api = Api(app)
@@ -29,7 +31,6 @@ def ipv62mac(ipv6):
     mac_parts[0] = '%02x' % (int(mac_parts[0], 16) ^ 2)
     del mac_parts[4]
     del mac_parts[3]
-
     return ':'.join(mac_parts)
 
 

scheduler/main.py

@@ -14,8 +14,9 @@ from helper import (get_suitable_host, dead_host_mitigation, dead_host_detection
                     assign_host, NoSuitableHostFound)
 
 
-
 def main():
+    logging.info("%s SESSION STARTED %s", '*' * 5, '*' * 5)
+
     pending_vms = []
 
     for request_iterator in [
@@ -85,5 +86,5 @@ def main():
                         logging.info("No Resource Left. Emailing admin....")
 
 
-logging.info("%s SESSION STARTED %s", '*' * 5, '*' * 5)
+if __name__ == "__main__":
     main()