From 7422bba8a342a10ed6652ef907db6c9f069591aa Mon Sep 17 00:00:00 2001
From: mcolta <mcolta@griddynamics.com>
Date: Thu, 15 May 2025 07:54:43 +0300
Subject: [PATCH 1/2] Covered code with types

---
 index.ts | 157 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 157 insertions(+)
 create mode 100644 index.ts

diff --git a/index.ts b/index.ts
new file mode 100644
index 0000000..f675c83
--- /dev/null
+++ b/index.ts
@@ -0,0 +1,157 @@
+type ObserverHandlers = {
+    next: (value: RequestType) => void;
+    error: (error: Error) => void;
+    complete: () => void;
+}
+
+class Observer {
+    private handlers: ObserverHandlers;
+    private isUnsubscribed: boolean;
+    _unsubscribe: () => void;
+
+    constructor(handlers: ObserverHandlers) {
+      this.handlers = handlers;
+      this.isUnsubscribed = false;
+    }
+  
+    next(value: RequestType) {
+      if (this.handlers.next && !this.isUnsubscribed) {
+        this.handlers.next(value);
+      }
+    }
+  
+    error(error: Error) {
+      if (!this.isUnsubscribed) {
+        if (this.handlers.error) {
+          this.handlers.error(error);
+        }
+  
+        this.unsubscribe();
+      }
+    }
+  
+    complete() {
+      if (!this.isUnsubscribed) {
+        if (this.handlers.complete) {
+          this.handlers.complete();
+        }
+  
+        this.unsubscribe();
+      }
+    }
+  
+    unsubscribe() {
+      this.isUnsubscribed = true;
+  
+      if (this._unsubscribe) {
+        this._unsubscribe();
+      }
+    }
+}
+  
+class Observable {
+    private _subscribe: (observer: Observer) => () => void;
+
+    constructor(subscribe: (observer: Observer) => () => void) {
+        this._subscribe = subscribe;
+    }
+
+    static from(values: RequestType[]) {
+        return new Observable((observer: Observer) => {
+            values.forEach((value: RequestType) => observer.next(value));
+
+            observer.complete();
+
+            return () => {
+                console.log('unsubscribed');
+            };
+        });
+    }
+
+    subscribe(obs: ObserverHandlers) {
+        const observer = new Observer(obs);
+
+        observer._unsubscribe = this._subscribe(observer);
+
+        return ({
+            unsubscribe() {
+                observer.unsubscribe();
+            }
+        });
+    }
+}
+  
+const HTTP_POST_METHOD = 'POST';
+const HTTP_GET_METHOD = 'GET';
+
+const HTTP_STATUS_OK = 200;
+const HTTP_STATUS_INTERNAL_SERVER_ERROR = 500;
+
+type User =  {
+    name: string;
+    age: number;
+    roles: string[];
+    createdAt: Date;
+    isDeleated: boolean;
+}
+
+
+const userMock: User = {
+    name: 'User Name',
+    age: 26,
+    roles: [
+        'user',
+        'admin'
+    ],
+    createdAt: new Date(),
+    isDeleated: false,
+};
+
+type RequestType = {
+    method: string;
+    host: string;
+    path: string;
+    body?: User;
+    params?: {
+        [key: string]: string;
+    }
+}
+
+const requestsMock: RequestType[] = [
+    {
+        method: HTTP_POST_METHOD,
+        host: 'service.example',
+        path: 'user',
+        body: userMock,
+        params: {},
+    },
+    {
+        method: HTTP_GET_METHOD,
+        host: 'service.example',
+        path: 'user',
+        params: {
+        id: '3f5h67s4s'
+        },
+    }
+];
+
+const handleRequest = (request: RequestType) => {
+    // handling of request
+    return {status: HTTP_STATUS_OK};
+};
+const handleError = (error: Error) => {
+    // handling of error
+    return {status: HTTP_STATUS_INTERNAL_SERVER_ERROR};
+};
+
+const handleComplete = () => console.log('complete');
+
+const requests$ = Observable.from(requestsMock);
+
+const subscription = requests$.subscribe({
+    next: handleRequest,
+    error: handleError,
+    complete: handleComplete
+});
+
+subscription.unsubscribe();

From ce6d34118d4bf8a06006c51848bda107148f34f0 Mon Sep 17 00:00:00 2001
From: mcolta <mcolta@griddynamics.com>
Date: Mon, 9 Jun 2025 16:55:57 +0300
Subject: [PATCH 2/2] Add types to the top

---
 index.ts | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/index.ts b/index.ts
index f675c83..bb83a70 100644
--- a/index.ts
+++ b/index.ts
@@ -1,3 +1,13 @@
+type RequestType = {
+  method: string;
+  host: string;
+  path: string;
+  body?: User;
+  params?: {
+      [key: string]: string;
+  }
+}
+
 type ObserverHandlers = {
     next: (value: RequestType) => void;
     error: (error: Error) => void;
@@ -95,7 +105,6 @@ type User =  {
     isDeleated: boolean;
 }
 
-
 const userMock: User = {
     name: 'User Name',
     age: 26,
@@ -107,16 +116,6 @@ const userMock: User = {
     isDeleated: false,
 };
 
-type RequestType = {
-    method: string;
-    host: string;
-    path: string;
-    body?: User;
-    params?: {
-        [key: string]: string;
-    }
-}
-
 const requestsMock: RequestType[] = [
     {
         method: HTTP_POST_METHOD,