What is Dockerfile, image, container !

What is Dockerfile, Docker Image and container ?

When I started reading about Docker, I was confused about the relationship between Docker file vs docker image vs docker container !

Short answer to my question is:

  • Docker file is where I need to script my steps on what actions to be done before I make a docker image.
  • A sample docker file as below:
  • here below in the code, I am pulling JDK environment in line 1.
  • copying a java class to app directory in line 2,
  • setting app as working directory in line 3 for my docker container after i convert image to container.
  • Then finally running my app in line 4.
    FROM java:8-jdk-alpine
    COPY HelloWorld.class /app/
    WORKDIR /app
    ENTRYPOINT [“java”,”HelloWorld”]
  • Docker image is created using the above docker file by building it. (command : docker build -t myhelloworldapp . )
  • then spin up the container by using command : docker run myhelloworldapp

Docker Basics

Docker build command is used to generate docker images out of dockerfile line by line instructions.
Docker build is managed by docker daemon and not by CLI.

Docker build context can be a set of files in a specified directory or a git repository.

PATH is for directory and URL is for git

dockerignore file is used to ignore not required files.

Docker daemon runs each instructions from Dockerfile and commits each instructions to new Image.

Docker has build cache to speed up build process.

What is a Docker file, image, container !

What is Dockerfile, Docker image and Docker container?

When I started reading about Docker, I was confused about the relationship between Docker file vs docker image vs docker container !

  • Docker file is where I need to script my steps on what actions to be done before I make a docker image.
    a sample docker file as below: here below in the code,
  • I am pulling JDK environment in line 1.
  • Then copying a java class to app directory in line 2,
  • Then setting app as working directory in line 3 for my docker container after i convert image to container.
  • Then finally running my app in line 4.
    FROM java:8-jdk-alpine
    COPY HelloWorl.class /app/
    WORKDIR /app
    ENTRYPOINT [“java”,”HelloWorld”]
  • Docker image is created using the above docker file by building it. (command : docker build -t myhelloworldapp . )
    • Note: dockerfile generates read only layers during the image conversion. These read only layers are created based the dockerfile commandline instructions. Images are considered as executable packages and is predefined. Once it is made, it can not be changed unless new dockerfile is created.
  • then spin up the container by using command : docker run myhelloworldapp

What is Amazon S3

Amazon S3 enables companies to store massive amount of data in a secure way. S3 enables companies to store, retrieve data. 

Benefits:

  • High durability, availability, and scalability. S3 provides the most comprehensive compliance capabilities.
  • S3 allows  data storage up to 5 terabytes 
  • S3 provides a REST web services interface supporting any internet development tool kit.
  • S3 is available in any AWS region worldwide

 

 

 

 

Components of 3 tier architecture – Web server vs Application server vs Database server

  • Web server serves a web content (HTML and static content) over the HTTP protocol.
  • Application server is a container on which one can build and expose business logic and processes to client applications through various protocols like HTTP. Some cases it will have internal web server. Application server is heavy in terms of resource usage.
  • Database server refers to the back-end system of a database application using client/server architecture. The database server performs tasks such as data analysis, storage, data manipulation, archiving, and other non-user specific tasks

 

What is amazon aws

amazon-aws

Amazon Web Services (AWS) is a subsidiary of amazon.com. AWS currently provides more than 100 services and helps to setup high computing power, data storage, queuing, notification, machine learning, security, monitoring services available under AWS management console.

AWS Free Tier includes 750 hours of Linux and Windows t2.micro instances each month for one year as per Amazon website. Please check  //aws.amazon.com or //aws.amazon.com/ec2/ website for more accurate details and to confirm this.
 
The quickest way to learn AWS is by creating free tier aws account by clicking below link.
 

Different AWS cloud services?

VPC, EC2, S3, SNS, SQS,  ML, Developer tools, Analytics, IAM, Media services etc.
 

VPC

What is VPC?

VPC lets us to place our AWS resources in a virtual network the way we wanted. As you can see below VPC 3 tier architecture holds the resources and makes a secure communication between the internet and your VPC.
 
VPC 3 tier architecture using AWS cloud services as below:
 

Amazon VPC – 3 tier architecture

here in the above diagram, Availability zone 1 has Web server 1, App server 1 and DB server 1 orchestrated 

Similarly, Availability zone 1 has Web server 2, App server 2 and DB server 2 orchestrated. 

The load balancer is placed to handle the load between the servers

EC2

 

What is EC2?

EC2 stands for Amazon Elastic Compute Cloud is a cloud service provides secure, resizable compute capacity. In simple terms it allows us to setup a windows, Linux servers in 2-3 minutes.

How to setup a Windows server and Linux server?

Steps:
AWS Free account gives access to AWS console.
Create a free account and select Linux and Windows t2.micro instances under EC2 option under AWS Dashboard.
Follow the instructions and make sure select “Free Tier Eligible servers” and after learning the process, terminate servers as to avoid the usage of computing services and storage.
 
 
Benefits?
Quick – easy to create/terminate servers.
Inexpensive – Gives an option to select the matching server configurations to reduce cost.   
Secure – EC2 works along with VPC to provide high security with robust networking features.
Elastic Web scale computing – enable to increase/decrease server capacity in minutes by adding/removing 100 of servers simultaneously. 
Integration – easy integration to VPC, S3, RDS etc.
 
Please click on S3Amazon Simple Storage Service (Amazon S3) 
 
Please click on RDS Amazon Relational Database Service (Amazon RDS)
 
Please click on VPC– Amazon Virtual Private Cloud (Amazon VPC)
 
Please click on RPA Amazon Relational Database Service (Amazon RDS)

How to run selenium on linux server using Firefox binary

How to run selenium on linux server using Firefox binary

String Xport = System.getProperty(“lmportal.xvfb.id”, “:1”); // setup firefox binary to start Xvfb
final File ffPath = new File(System.getProperty(“lmportal.deploy.firefox.path”, “/usr/bin/firefox”));
FirefoxBinary ffBinary = new FirefoxBinary(ffPath);
ffBinary.setEnvironmentProperty(“DISPLAY”, Xport);

WebDriver driver = new FirefoxDriver(ffBinary, null);
driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
driver.get(“URL”);

How to handle the error popup on site security certificate is not trusted with chrome selenium python automation

How to handle the error popup on site security certificate is not trusted with chrome selenium python automation

For Chrome, add –ignore-certificate-errors in following code
options = webdriver.ChromeOptions()
options.add_argument(‘–ignore-certificate-errors’)
driver = webdriver.Chrome(chrome_options=options)
driver.get(‘URL’)

For the Internet Explorer, set acceptSslCerts desired capability as true:
capabilities = webdriver.DesiredCapabilities().INTERNETEXPLORER
capabilities[‘acceptSslCerts’] = True
driver = webdriver.Ie(capabilities=capabilities)
driver.get(‘URL’)

For Firefox, set accept_untrusted_certs as true

profile = webdriver.FirefoxProfile()
profile.accept_untrusted_certs = True
driver = webdriver.Firefox(firefox_profile=profile)
driver.get(‘URL’)

What are the limits in Salesforce

What are the limits in Salesforce

  1. Master detail relationships – 2
  2. Look up relationships – 40
  3. No.of dashboard components – 20
  4. Total Workflow rules per object – 500
  5. Active workflow rules – 50
  6. Approval process – 500
  7. Sharing rules (Criteria and Ownership based) – 300
  8. Sharing rules (Criteria based only) -50
  9. Validation rules – 100
  10. Field tracking – 20 (Additional 20 with chatter)
  11. No. of custom objects – 2000
  12. No. of custom fields – 500

Nia’s readings

Nia’s readings from Library,

  1. Ms. Leakey Is Freaky! – by Dan Gutman
  2. Ms. Hannah Is Bananas! – by Dan Gutman
  3. Nancy Drew and the Clue Crew- Case of the Sneaky Snowman by Carolyn Keene
  4. Diary of a Wimpy Kid Rodrick Rules by Jeff Kinney
  5. Help your Kids with Computer Coding 
  6. The phantom bully by Jeffrey Brown.
  7. Goosebump series Be careful what you wish for Samantha Byrd
  8. Goosebump series Night of the Living dummy Lindy Powell
  9. Goosebump series Night of the Living dummy Kris Powell
  10. Goosebump series Say Cheese and die Greg Banks
  11. Goosebump series Say Cheese and die Shari Walkar
  12. Goosebump series Be careful what you wish for – Samantha Byrd
  13. Goosebump series Stay out of the basement
  14. Carolines secret message
  15. Coach Hyatt is a Riot ! by Dan Gutman
  16. The Riddle of the Robin
  17. out of this world
  18. Dan Gutman – oh Valendtine we’ve lost our minds
  19. Sarah Mlynowski – whatever after dream on
  20. Sarah Mlynowski – whatever after bad hair day
  21. Lacey Little Mermaid Fairy
  22. Nancy Drew and the Clue Crew
  23. Miss Lazar is Bizarre
  24. Gemma and the Ultimate Standoff
  25. Owl Diaries Eva and Baby Mo
  26. A J’s Rules for school
  27. My first monologue
  28. When the Ghost Dog Howls
  29. Cinderella
  30. Harry Potter series, 8/8 books 
  31. Wings of fire, 13/15 
  32. Percy Jackson series 5/5Â