diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..6fbf59f
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,8 @@
+run:
+	@cd src/ && uvicorn server.asgi:application --reload --port 2121 && cd ..
+
+test:
+	@cd src/ && pytest -s server/
+
+testws:
+	@cd src/ && pytest -s server/tests/test_websockets.py
\ No newline at end of file
diff --git a/src/client/package-lock.json b/src/client/package-lock.json
index 2720f63..963df6a 100644
--- a/src/client/package-lock.json
+++ b/src/client/package-lock.json
@@ -2434,6 +2434,12 @@
         "yarn": ">= 1.13.0"
       }
     },
+    "node_modules/@socket.io/component-emitter": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/@socket.io/component-emitter/-/component-emitter-3.1.0.tgz",
+      "integrity": "sha512-+9jVqKhRSpsc591z5vX+X5Yyw+he/HCB4iQ/RYxw35CEPaY1gnsNE43nf9n9AaYjAQrTiI/mOwKUKdUs9vf7Xg==",
+      "dev": true
+    },
     "node_modules/@tootallnate/once": {
       "version": "1.1.2",
       "dev": true,
@@ -2464,11 +2470,6 @@
         "@types/node": "*"
       }
     },
-    "node_modules/@types/component-emitter": {
-      "version": "1.2.11",
-      "dev": true,
-      "license": "MIT"
-    },
     "node_modules/@types/connect": {
       "version": "3.4.35",
       "dev": true,
@@ -2488,13 +2489,18 @@
     },
     "node_modules/@types/cookie": {
       "version": "0.4.1",
-      "dev": true,
-      "license": "MIT"
+      "resolved": "https://registry.npmjs.org/@types/cookie/-/cookie-0.4.1.tgz",
+      "integrity": "sha512-XW/Aa8APYr6jSVVA1y/DEIZX0/GMKLEVekNG727R8cs56ahETkRAy/3DR7+fJyh7oUgGwNQaRfXCun0+KbWY7Q==",
+      "dev": true
     },
     "node_modules/@types/cors": {
-      "version": "2.8.12",
+      "version": "2.8.13",
+      "resolved": "https://registry.npmjs.org/@types/cors/-/cors-2.8.13.tgz",
+      "integrity": "sha512-RG8AStHlUiV5ysZQKq97copd2UmVYw3/pRMLefISZ3S1hK104Cwm7iLQ3fTKx+lsUH2CE8FlLaYeEA2LSeqYUA==",
       "dev": true,
-      "license": "MIT"
+      "dependencies": {
+        "@types/node": "*"
+      }
     },
     "node_modules/@types/eslint": {
       "version": "8.4.2",
@@ -3207,8 +3213,9 @@
     },
     "node_modules/base64id": {
       "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/base64id/-/base64id-2.0.0.tgz",
+      "integrity": "sha512-lGe34o6EHj9y3Kts9R4ZYs/Gr+6N7MCaMlIFA3F1R2O5/m7K06AxfSeO5530PEERE6/WyEg3lsuyw4GHlPZHog==",
       "dev": true,
-      "license": "MIT",
       "engines": {
         "node": "^4.5.0 || >= 5.9"
       }
@@ -3645,11 +3652,6 @@
       "dev": true,
       "license": "MIT"
     },
-    "node_modules/component-emitter": {
-      "version": "1.3.0",
-      "dev": true,
-      "license": "MIT"
-    },
     "node_modules/compressible": {
       "version": "2.0.18",
       "dev": true,
@@ -3792,8 +3794,9 @@
     },
     "node_modules/cookie": {
       "version": "0.4.2",
+      "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.4.2.tgz",
+      "integrity": "sha512-aSWTXFzaKWkvHO1Ny/s+ePFpvKsPnjc551iI41v3ny/ow6tBG5Vd+FuqGNhh1LxOmVzOlGUriIlOaokOvhaStA==",
       "dev": true,
-      "license": "MIT",
       "engines": {
         "node": ">= 0.6"
       }
@@ -3904,8 +3907,9 @@
     },
     "node_modules/cors": {
       "version": "2.8.5",
+      "resolved": "https://registry.npmjs.org/cors/-/cors-2.8.5.tgz",
+      "integrity": "sha512-KIHbLJqu73RGr/hnbrO9uBeixNGuvSQjul/jdFvS/KFSIH1hWVd1ng7zOHx+YrEfInLG7q4n6GHQ9cDtxv/P6g==",
       "dev": true,
-      "license": "MIT",
       "dependencies": {
         "object-assign": "^4",
         "vary": "^1"
@@ -4504,9 +4508,10 @@
       }
     },
     "node_modules/engine.io": {
-      "version": "6.2.1",
+      "version": "6.4.2",
+      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-6.4.2.tgz",
+      "integrity": "sha512-FKn/3oMiJjrOEOeUub2WCox6JhxBXq/Zn3fZOMCBxKnNYtsdKjxhl7yR3fZhM9PV+rdE75SU5SYMc+2PGzo+Tg==",
       "dev": true,
-      "license": "MIT",
       "dependencies": {
         "@types/cookie": "^0.4.1",
         "@types/cors": "^2.8.12",
@@ -4517,16 +4522,17 @@
         "cors": "~2.8.5",
         "debug": "~4.3.1",
         "engine.io-parser": "~5.0.3",
-        "ws": "~8.2.3"
+        "ws": "~8.11.0"
       },
       "engines": {
         "node": ">=10.0.0"
       }
     },
     "node_modules/engine.io-parser": {
-      "version": "5.0.4",
+      "version": "5.0.6",
+      "resolved": "https://registry.npmjs.org/engine.io-parser/-/engine.io-parser-5.0.6.tgz",
+      "integrity": "sha512-tjuoZDMAdEhVnSFleYPCtdL2GXwVTGtNjoeJd9IhIG3C1xs9uwxqRNEu5WpnDZCaozwVlK/nuQhpodhXSIMaxw==",
       "dev": true,
-      "license": "MIT",
       "engines": {
         "node": ">=10.0.0"
       }
@@ -7532,8 +7538,9 @@
     },
     "node_modules/object-assign": {
       "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
+      "integrity": "sha512-rJgTQnkUnH1sFw8yT6VSU3zD3sWmu6sZhIseY8VX+GRu3P6F7Fu+JNDoXfklElbLJSnc3FUQHVe4cU5hj+BcUg==",
       "dev": true,
-      "license": "MIT",
       "engines": {
         "node": ">=0.10.0"
       }
@@ -9357,33 +9364,38 @@
       }
     },
     "node_modules/socket.io": {
-      "version": "4.5.1",
+      "version": "4.6.1",
+      "resolved": "https://registry.npmjs.org/socket.io/-/socket.io-4.6.1.tgz",
+      "integrity": "sha512-KMcaAi4l/8+xEjkRICl6ak8ySoxsYG+gG6/XfRCPJPQ/haCRIJBTL4wIl8YCsmtaBovcAXGLOShyVWQ/FG8GZA==",
       "dev": true,
-      "license": "MIT",
       "dependencies": {
         "accepts": "~1.3.4",
         "base64id": "~2.0.0",
         "debug": "~4.3.2",
-        "engine.io": "~6.2.0",
-        "socket.io-adapter": "~2.4.0",
-        "socket.io-parser": "~4.0.4"
+        "engine.io": "~6.4.1",
+        "socket.io-adapter": "~2.5.2",
+        "socket.io-parser": "~4.2.1"
       },
       "engines": {
         "node": ">=10.0.0"
       }
     },
     "node_modules/socket.io-adapter": {
-      "version": "2.4.0",
+      "version": "2.5.2",
+      "resolved": "https://registry.npmjs.org/socket.io-adapter/-/socket.io-adapter-2.5.2.tgz",
+      "integrity": "sha512-87C3LO/NOMc+eMcpcxUBebGjkpMDkNBS9tf7KJqcDsmL936EChtVva71Dw2q4tQcuVC+hAUy4an2NO/sYXmwRA==",
       "dev": true,
-      "license": "MIT"
+      "dependencies": {
+        "ws": "~8.11.0"
+      }
     },
     "node_modules/socket.io-parser": {
-      "version": "4.0.5",
+      "version": "4.2.2",
+      "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-4.2.2.tgz",
+      "integrity": "sha512-DJtziuKypFkMMHCm2uIshOYC7QaylbtzQwiMYDuCKy3OPkjLzu4B2vAhTlqipRHHzrI0NJeBAizTK7X+6m1jVw==",
       "dev": true,
-      "license": "MIT",
       "dependencies": {
-        "@types/component-emitter": "^1.2.10",
-        "component-emitter": "~1.3.0",
+        "@socket.io/component-emitter": "~3.1.0",
         "debug": "~4.3.1"
       },
       "engines": {
@@ -9959,9 +9971,9 @@
       }
     },
     "node_modules/ua-parser-js": {
-      "version": "0.7.34",
-      "resolved": "https://registry.npmjs.org/ua-parser-js/-/ua-parser-js-0.7.34.tgz",
-      "integrity": "sha512-cJMeh/eOILyGu0ejgTKB95yKT3zOenSe9UGE3vj6WfiOwgGYnmATUsnDixMFvdU+rNMvWih83hrUP8VwhF9yXQ==",
+      "version": "0.7.35",
+      "resolved": "https://registry.npmjs.org/ua-parser-js/-/ua-parser-js-0.7.35.tgz",
+      "integrity": "sha512-veRf7dawaj9xaWEu9HoTVn5Pggtc/qj+kqTOFvNiN1l0YdxwC1kvel57UCjThjGa3BHBihE8/UJAHI+uQHmd/g==",
       "dev": true,
       "funding": [
         {
@@ -10487,9 +10499,10 @@
       "license": "ISC"
     },
     "node_modules/ws": {
-      "version": "8.2.3",
+      "version": "8.11.0",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-8.11.0.tgz",
+      "integrity": "sha512-HPG3wQd9sNQoT9xHyNCXoDUa+Xw/VevmY9FoHyQ+g+rrMn4j6FB4np7Z0OhdTgjx6MgQLK7jwSy1YecU1+4Asg==",
       "dev": true,
-      "license": "MIT",
       "engines": {
         "node": ">=10.0.0"
       },
diff --git a/src/client/package.json b/src/client/package.json
index 4d3bf1a..27c7c12 100644
--- a/src/client/package.json
+++ b/src/client/package.json
@@ -7,7 +7,7 @@
     "url": "http://github.com/AbduazizZiyodov"
   },
   "license": "MIT",
-  "version": "2.2.0",
+  "version": "2.3.0",
   "main": "main.js",
   "productName": "Docker Dashboard",
   "keywords": [
diff --git a/src/client/src-tauri/Cargo.lock b/src/client/src-tauri/Cargo.lock
index d76f011..a574eb9 100644
--- a/src/client/src-tauri/Cargo.lock
+++ b/src/client/src-tauri/Cargo.lock
@@ -494,7 +494,7 @@ checksum = "bd0c93bb4b0c6d9b77f4435b0ae98c24d17f1c45b2ff844c6151a07256ca923b"
 
 [[package]]
 name = "docker-dashboard"
-version = "0.1.0"
+version = "2.3.0"
 dependencies = [
  "serde",
  "serde_json",
diff --git a/src/client/src-tauri/Cargo.toml b/src/client/src-tauri/Cargo.toml
index d172ac0..15551c7 100644
--- a/src/client/src-tauri/Cargo.toml
+++ b/src/client/src-tauri/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "docker-dashboard"
-version = "0.1.0"
+version = "2.3.0"
 description = "Simple lightweight GUI application for working with Docker"
 authors = ["abduaziz.ziyodov@mail.ru"]
 license = ""
diff --git a/src/client/src-tauri/tauri.conf.json b/src/client/src-tauri/tauri.conf.json
index c9d96f1..ee4d2fd 100644
--- a/src/client/src-tauri/tauri.conf.json
+++ b/src/client/src-tauri/tauri.conf.json
@@ -7,7 +7,7 @@
   },
   "package": {
     "productName": "docker-dashboard",
-    "version": "2.2.0"
+    "version": "2.3.0"
   },
   "tauri": {
     "allowlist": {
diff --git a/src/client/src/app/components/modal/run-container-modal/run-container-modal.component.ts b/src/client/src/app/components/modal/run-container-modal/run-container-modal.component.ts
index 430fcf7..1ae8236 100644
--- a/src/client/src/app/components/modal/run-container-modal/run-container-modal.component.ts
+++ b/src/client/src/app/components/modal/run-container-modal/run-container-modal.component.ts
@@ -67,9 +67,6 @@ export class RunContainerModalComponent implements OnInit {
     for (let key of ['env', 'firstPort', 'secondPort']) {
       delete containerData[key];
     }
-
-    console.log(containerData);
-
     return containerData;
   }
 
diff --git a/src/client/src/app/core/image/pull-image/pull-image.component.ts b/src/client/src/app/core/image/pull-image/pull-image.component.ts
index 97caec4..ecd227a 100644
--- a/src/client/src/app/core/image/pull-image/pull-image.component.ts
+++ b/src/client/src/app/core/image/pull-image/pull-image.component.ts
@@ -1,5 +1,5 @@
-import { ActivatedRoute, Router } from '@angular/router';
 import { Component, OnInit } from '@angular/core';
+import { ActivatedRoute, Router } from '@angular/router';
 
 import { environment } from '@env';
 import { Image } from '@models/image';
@@ -25,13 +25,11 @@ export class PullImageComponent implements OnInit {
   ) {}
 
   ngOnInit(): void {
-    let limit: number = 1;
-    this.imageService
-      .searchImages(this.repository, limit)
-      .subscribe((image: Image[]) => {
-        this.imageInfo = image ? image[0] : null;
-      });
+    this.performSearch();
+    this.fetchImages();
+  }
 
+  fetchImages(): void {
     this.imageService.getImages().subscribe((images: Image[]) => {
       this.pulledVersions = images.filter(
         (image: Image) => image.name == this.repository
@@ -40,11 +38,20 @@ export class PullImageComponent implements OnInit {
     });
   }
 
+  performSearch(): void {
+    let limit: number = 1;
+    this.imageService
+      .searchImages(this.repository, limit)
+      .subscribe((image: Image[]) => {
+        this.imageInfo = image ? image[0] : null;
+      });
+  }
+
   addImageToTasks(): void {
     this.ws.next({
       repository: this.repository,
       tag: this.selectedTag,
-      action: 'create',
+      action: 'add',
     });
 
     this.ws.asObservable().subscribe((data: any) => {
diff --git a/src/client/src/app/core/image/pull-list/pull-list.component.html b/src/client/src/app/core/image/pull-list/pull-list.component.html
index 7ec4e2e..ae0ffe2 100644
--- a/src/client/src/app/core/image/pull-list/pull-list.component.html
+++ b/src/client/src/app/core/image/pull-list/pull-list.component.html
@@ -18,48 +18,47 @@ <h2 class="text-center">
           >Multiple images </label
         ><br />
         Total:
-        <span class="text-success fw-bold">{{ tasks.length }}</span> tasks
+        <span class="text-success fw-bold">{{ numberOfTasks() }}</span> tasks
       </div>
 
       <blockquote
-        *ngIf="tasks.length == 0"
+        *ngIf="numberOfTasks() == 0"
         class="note w-75 m-auto text-center note-primary border mb-3"
       >
         No pending tasks yet ..
       </blockquote>
 
       <ul class="list-group list-group-light">
-        <li class="list-group-item m-auto" *ngFor="let task of tasks">
+        <li class="list-group-item m-auto" *ngFor="let key of getTaskKeys()">
           <p>
-            <span class="fw-bold">{{ task.repository }}</span>
-
+            <span class="fw-bold">{{ tasks[key].repository }}</span>
             <span
               class="mx-1 p-2 badge dodger-blue-bg rounded-pill text-lowercase"
             >
-              {{ task.tag }}</span
+              {{ tasks[key].tag }}</span
             >
-
             <button
               class="btn btn-sm btn-rounded btn-success text-capitalize"
-              (click)="start(task.repository, task.tag)"
+              (click)="start(tasks[key].repository, tasks[key].tag)"
               mdbTooltip="Click for start || continue pulling"
+              [disabled]="this.tasks[key].stream_data.length"
             >
               <i class="fas fa-play"></i>
             </button>
 
             <button
               class="btn btn-sm btn-rounded btn-danger text-capitalize mx-2"
-              (click)="delete(task.repository, task.tag)"
-              [disabled]="task.stream_data.length != 0"
+              (click)="delete(tasks[key].repository, tasks[key].tag)"
+              [disabled]="tasks[key].stream_data.length != 0"
             >
               <i class="fas fa-trash"></i>
             </button>
 
             <button
               class="btn btn-sm btn-light text-capitalize btn-rounded"
-              *ngIf="task.status"
+              *ngIf="tasks[key].status"
             >
-              {{ task.status }}
+              {{ tasks[key].status }}
             </button>
           </p>
           <div class="text-left">
@@ -68,7 +67,7 @@ <h2 class="text-center">
               cols="110"
               rows="2"
               disabled
-              [(ngModel)]="task.stream_data"
+              [(ngModel)]="tasks[key].stream_data"
               [scrollTop]="textarea.scrollHeight"
             >
             </textarea>
diff --git a/src/client/src/app/core/image/pull-list/pull-list.component.ts b/src/client/src/app/core/image/pull-list/pull-list.component.ts
index 09174b6..7092654 100644
--- a/src/client/src/app/core/image/pull-list/pull-list.component.ts
+++ b/src/client/src/app/core/image/pull-list/pull-list.component.ts
@@ -2,46 +2,82 @@ import { Component, OnInit } from '@angular/core';
 import { webSocket, WebSocketSubject } from 'rxjs/webSocket';
 
 import { environment } from '@env';
-import { Task } from '@models/image';
 import { ToastrService } from 'ngx-toastr';
 
+type Data = {
+  tag: string;
+  status: string;
+  repository: string;
+  stream_data: string;
+};
+
 @Component({
   selector: 'app-pull-list',
   templateUrl: './pull-list.component.html',
 })
 export class PullListComponent implements OnInit {
-  tasks!: Task[];
-  ws!: WebSocketSubject<any>;
+  tasks: { [key: string]: Data } = {};
   sockets: WebSocketSubject<any>[] = [];
   multiplePullingEnabled: boolean = false;
+  ws: WebSocketSubject<any> = webSocket(`${environment.wsUrl}/images/pull`);
 
   constructor(private toastr: ToastrService) {}
 
   ngOnInit(): void {
-    this.ws = webSocket(`${environment.wsUrl}/images/pull`);
+    this.fetchRepositories();
+  }
+
+  fetchRepositories(): void {
+    this.ws.next({ repository: '', action: 'list' });
 
-    this.ws.next({ action: 'list' });
     this.ws.asObservable().subscribe((data: any) => {
-      this.tasks = data;
+      this.createTasks(data);
     });
   }
+
+  createTasks(images: string[]): void {
+    for (let task of images) {
+      const [repository, tag] = this.splitRepositoryAndTag(task);
+
+      this.tasks[task] = {
+        stream_data: '',
+        status: '',
+        tag: tag,
+        repository: repository,
+      };
+    }
+  }
+
   start(repository: string, tag: string): void {
     this.toastr.warning('Creating & connecting websocket ...');
-    let ws = this.multiplePullingEnabled ? this.createNewSocket() : this.ws;
+    let full_repository_name = `${repository}:${tag}`;
+
+    let ws = this.multiplePullingEnabled ? this.createWebSocket() : this.ws;
+
     ws.next({ repository, tag, action: 'start' });
+
     ws.asObservable().subscribe((data: any) => {
-      this.tasks = data;
+      this.tasks[full_repository_name].status = data.status;
+      if (data.progress.length) {
+        this.tasks[full_repository_name].stream_data = this.tasks[
+          full_repository_name
+        ].stream_data
+          .concat('\n')
+          .concat(`[${data.id}] -> ${data.progress}`);
+      }
     });
   }
 
   delete(repository: string, tag: string): void {
+    let full_repository_name = `${repository}:${tag}`;
+
     this.ws.next({ repository, tag, action: 'delete' });
-    this.ws.asObservable().subscribe((data: any) => {
-      this.tasks = data;
+    this.ws.asObservable().subscribe((data: string[]) => {
+      delete this.tasks[full_repository_name];
     });
   }
 
-  createNewSocket(): WebSocketSubject<any> {
+  createWebSocket(): WebSocketSubject<any> {
     let socket = webSocket(`${environment.wsUrl}/images/pull`);
     this.sockets.push(socket);
     return socket;
@@ -53,4 +89,15 @@ export class PullListComponent implements OnInit {
     });
     this.ws.complete();
   }
+
+  splitRepositoryAndTag(full_repository_name: string): string[] {
+    return full_repository_name.split(':');
+  }
+  numberOfTasks(): number {
+    return Object.keys(this.tasks).length;
+  }
+
+  getTaskKeys(): string[] {
+    return Object.keys(this.tasks);
+  }
 }
diff --git a/src/client/src/app/core/models/image.ts b/src/client/src/app/core/models/image.ts
index 7c97ec9..3496d0c 100644
--- a/src/client/src/app/core/models/image.ts
+++ b/src/client/src/app/core/models/image.ts
@@ -9,12 +9,4 @@ export interface Image {
   is_pulled?: boolean;
   is_pulling?: boolean;
   tag: string;
-}
-export interface Task {
-  tag: string;
-  repository: string;
-
-  stream_data: string;
-  status: string;
-  action?: string;
-}
+}
\ No newline at end of file
diff --git a/src/server/asgi.py b/src/server/asgi.py
index 2500ed4..f192b37 100644
--- a/src/server/asgi.py
+++ b/src/server/asgi.py
@@ -1,5 +1,9 @@
 from starlette.applications import Starlette
 from server.settings import STARLETTE_SETTINGS
+from server.exceptions import exception_handlers
 
 
 application = Starlette(**STARLETTE_SETTINGS)
+
+for exception_class, handler in exception_handlers.items():
+    application.add_exception_handler(exception_class, handler)
diff --git a/src/server/exceptions.py b/src/server/exceptions.py
index 6e15a5b..95d4da8 100644
--- a/src/server/exceptions.py
+++ b/src/server/exceptions.py
@@ -1,6 +1,11 @@
 import json
+
+from typing import Any
+from pydantic import BaseModel
 from pydantic import ValidationError
+from docker.errors import DockerException
 
+import starlette.status as error
 from starlette.responses import JSONResponse
 from starlette.exceptions import HTTPException
 
@@ -8,8 +13,7 @@
 
 
 async def http_exception_handler(_, exc: HttpDockerException) -> JSONResponse:
-    """Starlette HTTP exception handler
-    """
+    """Starlette HTTP exception handler"""
     detail = exc.detail if isinstance(exc, HTTPException) else exc.explanation
 
     return JSONResponse(
@@ -20,10 +24,28 @@ async def http_exception_handler(_, exc: HttpDockerException) -> JSONResponse:
 
 
 async def pydantic_exception_handler(_, exc: ValidationError) -> JSONResponse:
-    """Handling pydantic validation exceptions
-    """
-    detail: dict = json.loads(exc.json())
-    return JSONResponse(detail, status_code=422)
+    """Handling pydantic validation exceptions"""
+    return JSONResponse(
+        content=json.load(exc.json()), status_code=error.HTTP_422_UNPROCESSABLE_ENTITY
+    )
+
+
+async def json_exception_handler(_, exc: json.decoder.JSONDecodeError) -> JSONResponse:
+    return JSONResponse(
+        status_code=error.HTTP_400_BAD_REQUEST, content={"error": "JSON decode error"}
+    )
+
+
+def websocket_request_handler(data: Any, Model: BaseModel) -> Any:
+    try:
+        return Model(**data), None
+    except ValidationError as exc:
+        return None, json.loads(exc.json())
 
 
-__all__ = ["pydantic_exception_handler", "http_exception_handler"]
+exception_handlers = {
+    HTTPException: http_exception_handler,
+    DockerException: http_exception_handler,
+    ValidationError: pydantic_exception_handler,
+    json.decoder.JSONDecodeError: json_exception_handler,
+}
diff --git a/src/server/handlers/api/__init__.py b/src/server/handlers/api/__init__.py
index aafb1bb..20dd782 100755
--- a/src/server/handlers/api/__init__.py
+++ b/src/server/handlers/api/__init__.py
@@ -4,7 +4,7 @@
     get_containers,
     get_logs,
     run_container,
-    start_stopped_container,
+    unpause_container,
     stop_container,
     remove_container
 )
@@ -24,7 +24,7 @@
     "get_containers",
     "get_logs",
     "run_container",
-    "start_stopped_container",
+    "unpause_container",
     "stop_container",
     "remove_container",
     # images
diff --git a/src/server/handlers/api/containers.py b/src/server/handlers/api/containers.py
index a95d2a9..b55a8a2 100755
--- a/src/server/handlers/api/containers.py
+++ b/src/server/handlers/api/containers.py
@@ -1,5 +1,3 @@
-import typing as t
-
 import docker
 from docker.models.containers import Container
 
@@ -7,6 +5,7 @@
 from starlette.requests import Request
 from starlette.responses import Response, JSONResponse
 
+from server import types
 from server.models import ContainerOptions
 from server.utils.api import container_as_dict
 
@@ -14,89 +13,60 @@
 
 
 async def get_containers(_) -> JSONResponse:
-    """Get the list of all containers (despite of their status)
-    * `docker ps -a`
-    """
-    containers: t.List[Container] = client.containers.list(all=True)
-    response = container_as_dict(containers)
-
-    return JSONResponse(response)
+    """Get the list of all containers."""
+    containers: types.Containers = client.containers.list(all=True)
+    return JSONResponse(container_as_dict(containers))
 
 
 async def get_container(request: Request) -> JSONResponse:
-    """Get container(single) by its ID (short ID ... doesn't matter)
-    * `docker ps -a ... [FILTER OPTIONS]`
-    """
-    container: Container = client.containers.get(
-        request.path_params["container_id"]
-    )
-    response: Container = container_as_dict(container)
-
-    return JSONResponse(response)
+    """Get container(single) by its ID."""
+    container: Container = client.containers.get(request.path_params["container_id"])
+    return JSONResponse(container_as_dict(container))
 
 
 async def run_container(request: Request) -> JSONResponse:
-    """Run new container by options in detached mode. Options defined
-    by ContainerOptions pydantic model.
-    * `docker run -d` (-d for detached mode)
-    """
+    """Create and run container by options in detached mode."""
     request_body = await request.json()
     container_options = ContainerOptions.parse_obj(request_body)
-    container = client.containers.run(
-        **container_options.dict(),
-        detach=True
-    )
+
+    container = client.containers.run(**container_options.dict(), detach=True)
 
     return JSONResponse(
-        container_as_dict(container),
-        status_code=status.HTTP_201_CREATED
+        container_as_dict(container), status_code=status.HTTP_201_CREATED
     )
 
 
-async def start_stopped_container(request: Request) -> JSONResponse:
-    """Start container, if it exists and status == stopped.
-    * `docker start`
-    """
-    container: Container = client.containers.get(
-        request.path_params["container_id"]
-    )
+async def unpause_container(request: Request) -> JSONResponse:
+    container: Container = client.containers.get(request.path_params["container_id"])
     container.start()
 
     return JSONResponse({"started": True})
 
 
 async def stop_container(request: Request) -> JSONResponse:
-    """Stop running container.
-    * `docker stop`
-    """
-    container: Container = client.containers.get(
-        request.path_params["container_id"]
-    )
+    """Stop running container."""
+    container: Container = client.containers.get(request.path_params["container_id"])
     container.stop()
 
-    return JSONResponse({"stopped": True, })
+    return JSONResponse(
+        {
+            "stopped": True,
+        }
+    )
 
 
 async def remove_container(request: Request) -> JSONResponse:
-    """Remove container by its ID.
-    * `docker rm` (force mode)
-    """
-    container: Container = client.containers.get(
-        request.path_params["container_id"]
-    )
-    container.remove(force=True)
+    """Remove container by its ID."""
+    force_remove: bool = request.query_params.get("force", False)
+
+    container: Container = client.containers.get(request.path_params["container_id"])
+    container.remove(force=force_remove)
 
     return Response(status_code=status.HTTP_204_NO_CONTENT)
 
 
 async def get_logs(request: Request) -> JSONResponse:
-    """Get logs from the inside of the container
-    * `docker logs`
-    """
-    container: Container = client.containers.get(
-        request.path_params["container_id"]
-    )
-
-    logs = container.logs().decode("utf-8")
+    """Get logs from the inside of the container"""
+    container: Container = client.containers.get(request.path_params["container_id"])
 
-    return JSONResponse({"logs": logs})
+    return JSONResponse({"logs": container.logs().decode("utf-8")})
diff --git a/src/server/handlers/api/images.py b/src/server/handlers/api/images.py
index b51e9c7..03db69c 100755
--- a/src/server/handlers/api/images.py
+++ b/src/server/handlers/api/images.py
@@ -1,20 +1,20 @@
 import docker
-import typing as t
 
 from docker.models.images import Image
-from docker.models.containers import Container
 
 import starlette.status as status
 from starlette.requests import Request
 from starlette.responses import Response, JSONResponse
 
+from server import types
+
 from server.utils.api import (
     image_as_dict,
     container_as_dict,
     filter_containers_by_image
 )
 
-from server.models import DockerSearchRequest, DockerPullRequest
+from server.models import DockerSearchRequest
 
 client = docker.from_env()
 
@@ -23,7 +23,7 @@ async def get_images(_) -> JSONResponse:
     """Get list of all docker images.
     * `docker images || docker image ls`
     """
-    images: t.List[Image] = client.images.list(all=True)
+    images: types.Images = client.images.list(all=True)
     response = image_as_dict(images, client)
 
     return JSONResponse(response)
@@ -72,7 +72,7 @@ async def get_containers_by_image(request: Request) -> JSONResponse:
     """Get list of containers by IMAGE_ID.
     * `docker ps -a ... [FILTER OPTIONS]`
     """
-    containers: t.List[Container] = filter_containers_by_image(
+    containers: types.Containers = filter_containers_by_image(
         request.path_params["image_id"], client
     )
 
diff --git a/src/server/handlers/urls.py b/src/server/handlers/urls.py
index 441ad8e..90301e2 100755
--- a/src/server/handlers/urls.py
+++ b/src/server/handlers/urls.py
@@ -1,51 +1,33 @@
-# Defined All API(websocket) routes
 from .api import *
 from .websockets import *
 
-from starlette.routing import (
-    Route,
-    WebSocketRoute
-)
+from starlette.routing import Route, WebSocketRoute
 
 
 container_routes = [
     Route("/api/containers", get_containers, methods=["GET"]),
+    Route("/api/containers/{container_id:str}", get_container, methods=["GET"]),
+    Route("/api/containers/run", run_container, methods=["POST"]),
     Route(
-        "/api/containers/{container_id:str}",
-        get_container, methods=["GET"]
-    ),
-    Route(
-        "/api/containers/run",
-        run_container, methods=["POST"]
-    ),
-    Route(
-        "/api/containers/{container_id:str}/start",
-        start_stopped_container, methods=["GET"]
-    ),
-    Route(
-        "/api/containers/{container_id:str}/stop",
-        stop_container, methods=["GET"]
+        "/api/containers/{container_id:str}/start", unpause_container, methods=["GET"]
     ),
+    Route("/api/containers/{container_id:str}/stop", stop_container, methods=["GET"]),
     Route(
         "/api/containers/{container_id:str}/delete",
-        remove_container, methods=["DELETE"]
+        remove_container,
+        methods=["DELETE"],
     ),
-    Route(
-        "/api/containers/{container_id:str}/logs",
-        get_logs, methods=["GET"]
-    )
+    Route("/api/containers/{container_id:str}/logs", get_logs, methods=["GET"]),
 ]
 
 image_routes = [
     Route("/api/images", get_images, methods=["GET"]),
     Route("/api/images/{image_id:str}", get_image, methods=["GET"]),
-    Route(
-        "/api/images/{image_id:str}/delete",
-        remove_image, methods=["DELETE"]
-    ),
+    Route("/api/images/{image_id:str}/delete", remove_image, methods=["DELETE"]),
     Route(
         "/api/images/{image_id:str}/containers",
-        get_containers_by_image, methods=["GET"]
+        get_containers_by_image,
+        methods=["GET"],
     ),
     Route("/api/images/search", search_image, methods=["POST"]),
 ]
@@ -54,5 +36,4 @@
     WebSocketRoute("/websocket/images/pull", PullImages),
 ]
 
-
 routes = container_routes + image_routes + websocket_routes
diff --git a/src/server/handlers/websockets/images.py b/src/server/handlers/websockets/images.py
index 8200520..370530a 100755
--- a/src/server/handlers/websockets/images.py
+++ b/src/server/handlers/websockets/images.py
@@ -1,80 +1,65 @@
-import asyncio
 import aiodocker
 import typing as t
-import nest_asyncio
+from docker.errors import DockerException
 
 from starlette.websockets import WebSocket
 from starlette.endpoints import WebSocketEndpoint
 
-from server.utils import (
-    tasks as task_utils,
-    api as api_utils,
-    websocket as websocket_utils,
-)
 from server.models.image import DockerPullRequest
+from server.exceptions import websocket_request_handler
 
-client, task_manager = aiodocker.Docker(), task_utils.Manager()
-
-nest_asyncio.apply()
+client = aiodocker.Docker()
 
 
 class PullImages(WebSocketEndpoint):
+    tasks: set = set({})
     encoding: str = "json"
 
-    async def on_connect(self, ws: WebSocket) -> t.NoReturn:
+    async def on_connect(self, ws: WebSocket) -> None:
         await ws.accept()
 
-    async def match_and_perform_action(self, ws: WebSocket, data: t.Any) -> t.NoReturn:
-        """Handle websocket request, perform action.
-        [task - image for pulling from dockerhub]
-        """
-        if data.action == "list":
-            await ws.send_json(task_manager.list())
-            return
-        elif data.action == "create":
-            await self.create_task(data)
-        elif data.action == "start":
-            await self.start_task(ws, data)
-        elif data.action == "delete":
-            await self.delete_task(data)
-        else:
-            await ws.send_json({"status": None})
+    async def pull(self, ws: WebSocket, data: DockerPullRequest) -> None:
+        stream_data: dict
+        async for stream_data in client.images.pull(
+            from_image=data.repository, tag=data.tag, stream=True
+        ):
+            await ws.send_json(stream_data)
 
-        await ws.send_json(task_manager.list())
-
-    async def on_receive(self, ws: WebSocket, data: t.Any) -> t.NoReturn:
-        body, error = await websocket_utils.validate_websocket_request(data)
+    async def on_receive(self, ws: WebSocket, data: t.Any) -> None:
+        """Handle `on_receive` event and errors, establish websocket session."""
+        pull_data: DockerPullRequest
+        pull_data, error = websocket_request_handler(data, DockerPullRequest)
 
         if error:
             await ws.send_json(error)
             return
 
-        # If there are no any errors, we should handle this request
-        await self.match_and_perform_action(ws, body)
-
-    async def create_task(self, body: DockerPullRequest) -> t.NoReturn:
-        task_manager.create(body)
-
-    async def delete_task(self, body: DockerPullRequest) -> t.NoReturn:
-        task_manager.delete(body)
-
-    async def start_task(self, ws: WebSocket, body: DockerPullRequest) -> t.NoReturn:
-        """Pull image from dockerhub. image.pulled = task.completed.
-        Handler streams pulling progress, nest_asyncio allows us
-        to pull many images at the same time.
-        """
-        if not task_manager.check_existence_of_task(body):
-            await ws.send_json({"detail": "First, you need to create a task."})
-            return
-
-        try:
-            async for stream_body in client.images.pull(
-                body.repository, tag=body.tag, stream=True
-            ):
-                task_manager.update(body, stream_body)
-                await ws.send_json(task_manager.list())
-            # if task.completed, then delete it.
-            task_manager.delete(body)
+        if pull_data.action == "start":
+            if pull_data.to_string() in self.tasks:
+                try:
+                    await self.pull(ws, pull_data)
+                    self.tasks.remove(pull_data.to_string())  # remove after pulling
+                except (DockerException, aiodocker.exceptions.DockerError) as exc:
+                    await ws.send_json({"error": exc.__str__()})
+            else:
+                await ws.send_json({"error": "Before pulling process, create task!"})
+
+        elif pull_data.action == "add":
+            self.tasks.add(pull_data.to_string())
+            await ws.send_json(
+                {"message": f"Image {pull_data.to_string() } is added to tasks!"}
+            )
+
+        elif pull_data.action == "list":
+            await ws.send_json(list(self.tasks))
+
+        elif pull_data.action == "delete":
+            if pull_data.to_string() in self.tasks:
+                self.tasks.remove(pull_data.to_string())
+                await ws.send_json(list(self.tasks))
+
+        elif pull_data.action == "clear":
+            self.tasks.clear()
 
-        except aiodocker.exceptions.DockerError as exc:
-            await ws.send_json({"error": exc.message})
+        else:
+            await ws.send_json({"error": "You picked wrong action!"})
diff --git a/src/server/models/__init__.py b/src/server/models/__init__.py
index 89dd19c..1002f11 100755
--- a/src/server/models/__init__.py
+++ b/src/server/models/__init__.py
@@ -1,4 +1,3 @@
-# All pydantic schemas defined
 from .container import ContainerOptions
 from .image import DockerPullRequest, DockerSearchRequest
 
diff --git a/src/server/models/image.py b/src/server/models/image.py
index e3d4f3a..c17134c 100644
--- a/src/server/models/image.py
+++ b/src/server/models/image.py
@@ -8,7 +8,9 @@ class DockerSearchRequest(BaseModel):
 
 
 class DockerPullRequest(BaseModel):
-    action: str
     repository: str
     tag: Optional[str] = "latest"
+    action: str
 
+    def to_string(self) -> str:
+        return f"{self.repository}:{self.tag}"
diff --git a/src/server/settings.py b/src/server/settings.py
index 5d51504..ebadf5e 100644
--- a/src/server/settings.py
+++ b/src/server/settings.py
@@ -1,32 +1,20 @@
 from starlette.routing import Route
 from starlette.middleware import Middleware
 from starlette.responses import JSONResponse
-from starlette.exceptions import HTTPException
 from starlette.middleware.cors import CORSMiddleware
 
-from pydantic import ValidationError
-from docker.errors import DockerException
-
-from server.exceptions import *
 from server.handlers.urls import routes
 
-routes += [
-    Route("/", lambda _:JSONResponse("ok"), methods=["GET"])
-]
+routes += [Route("/", lambda _: JSONResponse("ok"), methods=["GET"])]
 
 STARLETTE_SETTINGS: dict = {
     "routes": routes,
-    "exception_handlers": {
-        HTTPException: http_exception_handler,
-        DockerException: http_exception_handler,
-        ValidationError: pydantic_exception_handler
-    },
     "middleware": [
         Middleware(
             CORSMiddleware,
-            allow_origins=['*'],
+            allow_origins=["*"],
             allow_methods=["*"],
             allow_headers=["*"],
         )
-    ]
+    ],
 }
diff --git a/src/server/tests/conftest.py b/src/server/tests/conftest.py
index 55d3763..09f6111 100644
--- a/src/server/tests/conftest.py
+++ b/src/server/tests/conftest.py
@@ -1,21 +1,19 @@
-import json
 import pytest
 import docker
 
 from server.tests.settings import *
 
 
-@pytest.fixture(scope='session', autouse=True)
+@pytest.fixture(scope="session", autouse=True)
 def fixture():
     """
     We will need docker image for testing.
     Before running test cases, we should pull it.
     """
-    print(f"\nPulling docker image: {TEST_IMAGE_NAME}")
+    print(f"\n[PULLING]: {TEST_IMAGE_NAME}")
     docker_client = docker.from_env()
     pulled_image = docker_client.images.pull(
         TEST_IMAGE_NAME,
         tag=TEST_IMAGE_TAG,
-
     )
-    print(f"Pulled docker imaeg: {TEST_IMAGE_NAME}, id: {pulled_image.short_id}")
+    print(f"[PULLED]: {TEST_IMAGE_NAME}, id: {pulled_image.short_id}")
diff --git a/src/server/tests/settings.py b/src/server/tests/settings.py
index 927444e..3b5baf3 100755
--- a/src/server/tests/settings.py
+++ b/src/server/tests/settings.py
@@ -5,22 +5,17 @@
 TEST_IMAGE_ID: str = None
 TEST_IMAGE_NAME: str = "nginx"
 TEST_IMAGE_TAG: str = "1.18-alpine"
-
 TEST_PULL_IMAGE: str = "hello-world"
 
 
 @pytest.fixture
 def client():
     global application
-    
-    (
-        (
-    )
-    )
+
     return AsyncClient(
         app=application,
-        timeout=60*2,  # seconds
-        base_url="http://127.0.0.1:2121/api/"
+        timeout=60 * 2,  # seconds
+        base_url="http://127.0.0.1:2121/api/",
     )
 
 
@@ -31,5 +26,6 @@ def client():
     "TEST_IMAGE_ID",
     "TEST_IMAGE_NAME",
     "TEST_IMAGE_TAG",
-    "TEST_PULL_IMAGE"
+    "TEST_PULL_IMAGE",
+    "AsyncClient",
 ]
diff --git a/src/server/tests/test_containers.py b/src/server/tests/test_containers.py
index a644c55..8338bda 100644
--- a/src/server/tests/test_containers.py
+++ b/src/server/tests/test_containers.py
@@ -1,40 +1,37 @@
 import pytest
+import starlette.status as status
+
 from server.tests.settings import *
 
 
-async def test_get_containers(client):
+async def test_get_containers(client: AsyncClient):
     response = await client.get("containers")
 
-    assert response.status_code == 200
+    assert response.status_code == status.HTTP_200_OK
     assert response.text is not None
 
 
-async def test_run_container(client):
-
-    response = await client.post(
-        "containers/run",
-        json={"image": TEST_IMAGE_NAME}
-    )
+async def test_run_container(client: AsyncClient):
+    response = await client.post("containers/run", json={"image": TEST_IMAGE_NAME})
     body = response.json()
 
-    assert response.status_code == 201
-    assert body["image"]["name"]\
-        .startswith(TEST_IMAGE_NAME) == True
+    assert response.status_code == status.HTTP_201_CREATED
+    assert body["image"]["name"].startswith(TEST_IMAGE_NAME) == True
 
     pytest.CONTAINER_ID = body["id"]
 
 
-async def test_get_container(client):
+async def test_get_container(client: AsyncClient):
     response = await client.get(f"containers/{pytest.CONTAINER_ID}")
 
-    assert response.status_code == 200
+    assert response.status_code == status.HTTP_200_OK
     assert response.json()["id"] == pytest.CONTAINER_ID
 
 
-async def test_stop_container(client):
+async def test_stop_container(client: AsyncClient):
     response = await client.get(f"containers/{pytest.CONTAINER_ID}/stop")
 
-    assert response.status_code == 200
+    assert response.status_code == status.HTTP_200_OK
     assert response.json()["stopped"] == True
 
     response = await client.get(f"containers/{pytest.CONTAINER_ID}")
@@ -44,20 +41,22 @@ async def test_stop_container(client):
     assert body["status"] == "exited"
 
 
-async def test_start_container(client):
+async def test_start_container(client: AsyncClient):
     response = await client.get(f"containers/{pytest.CONTAINER_ID}/start")
 
-    assert response.status_code == 200
+    assert response.status_code == status.HTTP_200_OK
     assert response.json()["started"] == True
 
     response = await client.get(f"containers/{pytest.CONTAINER_ID}")
     body = response.json()
-
     assert body["id"] == pytest.CONTAINER_ID
     assert body["status"] == "running"
 
 
-async def test_delete_container(client):
-    response = await client.delete(f"containers/{pytest.CONTAINER_ID}/delete")
+async def test_delete_container(client: AsyncClient):
+    query_param: str = "force=true"
+    response = await client.delete(
+        f"containers/{pytest.CONTAINER_ID}/delete?{query_param}"
+    )
 
-    assert response.status_code == 204
+    assert response.status_code == status.HTTP_204_NO_CONTENT
diff --git a/src/server/tests/test_images.py b/src/server/tests/test_images.py
index 60734ae..ec6fe8e 100644
--- a/src/server/tests/test_images.py
+++ b/src/server/tests/test_images.py
@@ -1,21 +1,18 @@
 import pytest
 from httpx import AsyncClient
+import starlette.status as status
 
 from server.tests.settings import *
 
 
 def filter_images(images: list) -> dict:
-    return list(
-        filter(
-            lambda image: image["name"] == TEST_IMAGE_NAME, images
-        )
-    )
+    return list(filter(lambda image: image["name"] == TEST_IMAGE_NAME, images))
 
 
 async def test_get_images(client: AsyncClient):
     response = await client.get("images")
 
-    assert response.status_code == 200
+    assert response.status_code == status.HTTP_200_OK
     assert response.text is not None
 
     pytest.IMAGE_ID = filter_images(response.json())[0]["short_id"]
@@ -24,51 +21,47 @@ async def test_get_images(client: AsyncClient):
 async def test_get_image(client: AsyncClient):
     response = await client.get(f"images/{pytest.IMAGE_ID}")
 
-    assert response.status_code == 200
+    assert response.status_code == status.HTTP_200_OK
     assert response.json()["short_id"] == pytest.IMAGE_ID
 
 
 async def test_search_image(client: AsyncClient):
-    response = await client.post(
-        "images/search",
-        json={"term": TEST_IMAGE_NAME}
-    )
+    response = await client.post("images/search", json={"term": TEST_IMAGE_NAME})
 
-    assert response.status_code == 200
-    assert TEST_IMAGE_NAME in [
-        image["name"]
-        for image in response.json()
-    ]
+    assert response.status_code == status.HTTP_200_OK
+    assert TEST_IMAGE_NAME in [image["name"] for image in response.json()]
 
 
 async def test_get_containers_by_image(client: AsyncClient):
-    response = await client.post(
-        "containers/run",
-        json={"image": TEST_IMAGE_NAME}
-    )
+    async def on_begin():
+        response = await client.post("containers/run", json={"image": TEST_IMAGE_NAME})
 
-    assert response.status_code == 201
-    pytest.CONTAINER_ID = response.json()["id"]
+        assert response.status_code == status.HTTP_201_CREATED
+        pytest.CONTAINER_ID = response.json()["short_id"]
 
-    response = await client.get(
-        f"images/{pytest.IMAGE_ID}/containers"
-    )
+    await on_begin()
 
-    assert all([
-        container["image"]["name"].startswith(TEST_IMAGE_NAME)
-        for container in response.json()
-    ])
+    response = await client.get(f"images/{pytest.IMAGE_ID}/containers")
 
-    response = await client.delete(
-        f"containers/{pytest.CONTAINER_ID}/delete"
+    assert all(
+        [
+            container["image"]["name"].startswith(TEST_IMAGE_NAME)
+            for container in response.json()
+        ]
     )
 
-    assert response.status_code == 204
+    assert response.status_code == status.HTTP_200_OK
 
 
-async def test_delete_image(client: AsyncClient):
+async def test_delete_container_before_image(client: AsyncClient):
+    query_param: str = "force=true"
     response = await client.delete(
-        f"images/{TEST_IMAGE_NAME}/delete"
+        f"containers/{pytest.CONTAINER_ID}/delete?{query_param}"
     )
+    assert response.status_code == status.HTTP_204_NO_CONTENT
+
+
+async def test_delete_image(client: AsyncClient):
+    response = await client.delete(f"images/{TEST_IMAGE_NAME}/delete")
 
-    assert response.status_code == 204
+    assert response.status_code == status.HTTP_204_NO_CONTENT
diff --git a/src/server/tests/test_websockets.py b/src/server/tests/test_websockets.py
old mode 100755
new mode 100644
index a9519c8..9e5d497
--- a/src/server/tests/test_websockets.py
+++ b/src/server/tests/test_websockets.py
@@ -1,34 +1,74 @@
 from server.tests.settings import *
 
-from starlette.testclient import (
-    TestClient,
-    WebSocketTestSession,
-)
-
-
-async def test_list_tasks():
-    websocket_client: WebSocketTestSession
-    client = TestClient(application)
-    with client.websocket_connect("/websocket/images/pull") as websocket_client:
-        websocket_client.send_json({"action": "list", "repository": ""})
-        data = websocket_client.receive_json()
-        assert data == []
-
-
-async def test_create_task():
-    websocket_client: WebSocketTestSession
-    client = TestClient(application)
-    with client.websocket_connect("/websocket/images/pull") as websocket_client:
-        websocket_client.send_json({"action": "create", "repository": TEST_PULL_IMAGE})
-        data = websocket_client.receive_json()
-        assert isinstance(data, (list)) and len(data) == 1
-        assert any([TEST_PULL_IMAGE in task.values() for task in data])
-
-
-async def test_delete_task():
-    websocket_client: WebSocketTestSession
-    client = TestClient(application)
-    with client.websocket_connect("/websocket/images/pull") as websocket_client:
-        websocket_client.send_json({"action": "delete", "repository": TEST_PULL_IMAGE})
-        data = websocket_client.receive_json()
-        assert data == []
\ No newline at end of file
+
+from starlette.testclient import TestClient
+from starlette.testclient import WebSocketTestSession
+
+import nest_asyncio
+
+nest_asyncio.apply()
+
+CONNECTION_MESSAGE: str = "Connection established"
+TEST_REPO: str = "python"
+TEST_TAG: str = "3.10-alpine"
+
+client = TestClient(app=application)
+request_body = {"repository": TEST_REPO, "tag": TEST_TAG, "action": ""}
+
+
+def test_add_tasks() -> None:
+    websocket: WebSocketTestSession
+    with client.websocket_connect("websocket/images/pull") as websocket:
+        request_body["action"] = "add"
+        websocket.send_json(request_body)
+        data: dict = websocket.receive_json()
+
+        assert "message" in data.keys()
+        assert TEST_REPO in data["message"]
+
+
+def test_list_of_tasks() -> None:
+    websocket: WebSocketTestSession
+    with client.websocket_connect("websocket/images/pull") as websocket:
+        request_body["action"] = "list"
+        websocket.send_json(request_body)
+
+        data: dict = websocket.receive_json()
+
+        assert f"{TEST_REPO}:{TEST_TAG}" in data
+
+
+def test_delete_tasks() -> None:
+    websocket: WebSocketTestSession
+    with client.websocket_connect("websocket/images/pull") as websocket:
+        request_body["action"] = "delete"
+        websocket.send_json(request_body)
+        data: dict = websocket.receive_json()
+
+        assert f"{TEST_REPO}:{TEST_TAG}" not in data
+
+
+def test_wrong_action() -> None:
+    websocket: WebSocketTestSession
+    with client.websocket_connect("websocket/images/pull") as websocket:
+        # try to send another action
+        request_body["action"] = "some_action"
+
+        websocket.send_json(request_body)
+        data: dict = websocket.receive_json()
+
+        assert "error" in data.keys()
+
+
+def test_pull_images() -> None:
+    websocket: WebSocketTestSession
+    with client.websocket_connect("websocket/images/pull") as websocket:
+        # create new task before pulling
+        request_body["action"] = "add"
+
+        websocket.send_json(request_body)
+        data: dict = websocket.receive_json()
+
+        assert f"{TEST_REPO}:{TEST_TAG}" in data["message"]
+
+        # complete with pulling ...
diff --git a/src/server/types.py b/src/server/types.py
index 1aafaff..7b4ad66 100644
--- a/src/server/types.py
+++ b/src/server/types.py
@@ -10,5 +10,5 @@
 
 HttpDockerException = Union[HTTPException, DockerException]
 
-Images:TypeAlias = List[Image]
-Containers:TypeAlias = List[Container]
\ No newline at end of file
+Images: TypeAlias = List[Image]
+Containers: TypeAlias = List[Container]
diff --git a/src/server/utils/stats.py b/src/server/utils/stats.py
index 78d8489..d0cc593 100644
--- a/src/server/utils/stats.py
+++ b/src/server/utils/stats.py
@@ -6,32 +6,35 @@
 def get_image_name_tag(image: Image) -> t.Tuple[str, str]:
     """Get image's name from model.
     Attrs dictionary of image model:
-        e.g. RepoTags: ['python:latest']
+    e.g. RepoTags: ['python:latest']
 
     Returns tuple, first element is image_name
     second is image_tag
     """
-    attrs = image.attrs
+    attrs: dict = image.attrs
 
     if attrs.get("RepoTags") == []:
         return "<none>", "<none_tag>"
 
     repo_tag: str = attrs.get("RepoTags")[0].split(":")
+
     return repo_tag[0], repo_tag[1]
 
 
-def human_readable_size(size: int = None, image: Image = None, precision: int = 1, system: str = 'decimal') -> str:
+def human_readable_size(
+    size: int = None, image: Image = None, precision: int = 1, system: str = "decimal"
+) -> str:
     """Converts size (in bytes) to human readable system.
     It can be used with 2 system, docker CLI uses decimal (10's power).
     """
     if not size and image:
-        size = image.attrs['Size']
+        size = image.attrs["Size"]
 
-    suffixIndex = 0
-    decimal_suffixes = ['Byte', 'KB', 'MB', 'GB', 'TB']
-    binary_suffixes = ['Byte', 'KiB', 'MiB', 'GiB', 'TiB']
+    suffixIndex: int = 0
+    decimal_suffixes: list[str] = ["Byte", "KB", "MB", "GB", "TB"]
+    binary_suffixes: list[str] = ["Byte", "KiB", "MiB", "GiB", "TiB"]
 
-    if system == 'decimal':
+    if system == "decimal":
         divisor = min_size = 10**3
         suffixes = decimal_suffixes
     else:
@@ -40,7 +43,7 @@ def human_readable_size(size: int = None, image: Image = None, precision: int =
 
     while size > min_size and suffixIndex < 4:
         suffixIndex += 1
-        size = size/divisor
+        size = size / divisor
 
     return "%.*f%s" % (precision, size, suffixes[suffixIndex])
 
@@ -51,20 +54,21 @@ def calculate_image_disk_space(client: DockerClient):
     unused_images_size: int = 0
 
     for image in client.images.list(all=True):
+        if image.attrs["RepoTags"] == []:
+            unused_images_size += image.attrs["Size"]
 
-        if image.attrs['RepoTags'] == []:
-            unused_images_size += image.attrs['Size']
-
-        total_images_size += image.attrs['Size']
+        total_images_size += image.attrs["Size"]
 
         image_name, _ = get_image_name_tag(image)
 
-        images.append({
-            image_name: human_readable_size(image=image),
-        })
+        images.append(
+            {
+                image_name: human_readable_size(image=image),
+            }
+        )
 
     return {
-        'total': human_readable_size(total_images_size),
-        'unsused': human_readable_size(unused_images_size),
-        'images ': images
+        "total": human_readable_size(total_images_size),
+        "unsused": human_readable_size(unused_images_size),
+        "images ": images,
     }
diff --git a/src/server/utils/tasks.py b/src/server/utils/tasks.py
deleted file mode 100755
index f4354ea..0000000
--- a/src/server/utils/tasks.py
+++ /dev/null
@@ -1,95 +0,0 @@
-import typing as t
-from pydantic.main import ModelMetaclass
-
-from server.models.image import DockerPullRequest
-
-
-class Task:
-    """Simple class that represents tasks for pulling docker images.
-    """
-
-    def __init__(self, repository: str, tag: str) -> None:
-        self.repository, self.tag = repository, tag
-        self.stream_data, self.status = "", ""
-
-    def get(self, __name: str) -> t.Any:
-        return super().__getattribute__(__name)
-
-    def __eq__(self, __obj: t.Any) -> bool:
-        """Overload equality operator.
-        """
-        if isinstance(type(__obj), (ModelMetaclass)):
-            __obj = __obj.dict()
-
-        if isinstance(__obj, (dict, type(self))):
-            return bool(
-                self.repository == __obj.get("repository")
-                and
-                self.tag == __obj.get("tag")
-            )
-
-        return False
-
-    def to_dict(self) -> t.Dict[str, str]:
-        """From object to dictionary
-        """
-        return dict(
-            repository=self.repository,
-            tag=self.tag,
-            stream_data=self.stream_data,
-            status=self.status
-        )
-
-
-class Manager:
-    tasks: t.List[Task] = list()
-
-    def list(self) -> t.List[Task]:
-        """Convert all tasks to python dict.
-        """
-        return list(map(lambda task: task.to_dict(), self.tasks))
-
-    def create(self, body: DockerPullRequest) -> None:
-        if not self.check_existence_of_task(body):
-            self.tasks.append(Task(body.repository, body.tag))
-
-    def update(self, body: DockerPullRequest, stream: dict) -> None:
-        """In the pulling progress, application should update
-        stream records. This method takes stream as an argument, 
-        adds it to the task's stream data by formatting it.
-        """
-        for task in self.tasks:
-            if task == body:
-                status, stream = self.format_stream_body(stream)
-
-                task.status = status
-                task.stream_data += stream
-
-    def delete(self, body: DockerPullRequest) -> None:
-        for task in self.tasks:
-            if task == body:
-                self.tasks.remove(task)
-
-    def format_stream_body(self, stream: dict) -> t.Tuple[str, str]:
-        body_text: str = ""
-        keys = stream.keys()
-
-        if "id" in keys:
-            body_text += "Id: {} ".format(
-                stream.get("id")
-            )
-
-        if "progress" in keys:
-            body_text += "| Progress: {}".format(
-                stream.get("progress")
-            )
-
-        body_text += "\n"
-
-        return stream.get("status"), body_text
-
-    def check_existence_of_task(self, body: DockerPullRequest) -> bool:
-        for task in self.tasks:
-            if task == body:
-                return True
-        return False
diff --git a/src/server/utils/websocket.py b/src/server/utils/websocket.py
deleted file mode 100644
index 487b3fb..0000000
--- a/src/server/utils/websocket.py
+++ /dev/null
@@ -1,20 +0,0 @@
-import json
-from pydantic import ValidationError, BaseModel
-
-import server.types as types
-from server.models import DockerPullRequest
-
-
-async def validate_websocket_request(data: dict, PydanticModel: BaseModel = DockerPullRequest) -> types.ModelOrDict:
-    """Util function for validating websocket requests via pydantic models.
-    """
-    try:
-        if "DockerPullRequest" in str(PydanticModel):
-            if data.get("action") == "list":
-                data["repository"] = ""
-
-        body = PydanticModel(**data)
-        return body, None
-        
-    except ValidationError as exc:
-        return None, {"detail": json.loads(exc.json())}