Back-end Developer
Docker is a platform for developers and sysadmins to develop, deploy, and run applications with containers. The use of Linux containers to deploy applications is called containerization. Containers are not new, but their use for easily deploying applications is
Ensure you’ve installed Docker already by the command:
docker --version
Run a docker image
docker container run httpd:2.4
Note: while httpd is the image name, “2.4” is the version of this image
An index is a data structure that optimizes searching and accessing the data. It’s like an index at the back of a book. Indexing is one of the ways that will optimize your database searching and access is having indexes on the columns that you usually access the table using it. Continue reading “[MySQL] Indexing table”
EXPLAIN is one of the most powerful tools at your understanding and optimizing troublesome MySQL queries. However, many developers rarely make use of it. In this blog post, I would like to share what the output of
EXPLAIN can be and how to use it to optimize your schema and queries.
Continue reading “[MySQL] EXPLAIN the Queries”
What is the stack? It’s a special region of your computer’s memory that stores temporary variables created by each function (including the functionmain()). The stack is a “LIFO” (last in, first out) data structure, that is managed and optimized by the CPU quite closely. Every time a function declares a new variable, it is “pushed” onto the stack. Then every time a function exits, all of the variables pushed onto the stack by that function, are freed (that is to say, they are deleted). Once a stack variable is freed, that region of memory becomes available for other stack variables.
Task queues are used as a mechanism to distribute work across threads or machines. The task is appended to the queue that calls task queue. Dedicated worker processes constantly monitor task queues for new work to perform.
Celery communicates via messages, usually using a broker to mediate between clients and workers. To initiate a task the client adds a message to the queue, the broker then delivers that message to a worker.
A Celery system can consist of multiple workers and brokers, giving way to high availability and horizontal scaling.
In Linux, Cron is a daemon/service that executes shell commands periodically on a given schedule. Cron is driven by a crontab, a configuration file that holds details of what commands are to be run along with a timetable of when to run them.
Use virtualenv to create isolated Python environments. Run the following command in your shell to install virtualenv
pip install virtualenv
create an isolated environment with the following command:
mkdir /venvs cd /venvs virtualenv django-blog
Continue reading “[Django – Blog Application] – P.1 – Setup environment”
RabbitMQ là một message broker sử dụng nhiều giao thức và phổ biến là giao thức AMQP – Advanced Message Queue Protocol. Được lập trình bằng ngôn ngữ Erlang, RabbitMQ cung cấp cho developer một service trung gian để giao tiếp giữa nhiều thành phần trong một hệ thống. RabbitMQ sẽ nhận message đến từ các thành phần khác nhau trong hệ thống (Producer), lưu trữ chúng an toàn trước khi đẩy đến đích (Consumer).
Continue reading “[RabbitMQ – P.1] Cài đặt RabbitMQ Server trên Ubuntu 16.04 & 14.04”
The author must trust and respect the reviewers enough to be receptive to their comments. Similarly, the reviewers must show respect for the author’s talent and hard work. Reviewers should thoughtfully select the words they use to raise an issue, focusing on what they observed about the product. Saying, “I didn’t see where these variables were initialized” is likely to elicit a constructive response, whereas “You didn’t initialize these variables” might get the author’s hackles up.
Continue reading “[Đọc sách] Effective Code Reviews”