DEV Community: Reybis Ceballos

Oracle APEX Stack on Docker

Reybis Ceballos — Sun, 23 Aug 2020 20:47:49 +0000

Oracle APEX Stack

Oracle APEX
Prerequisites
The Setup
Oracle APEX Stack Up!
Oracle APEX Stack Down!
Optional: Custom Setup
Credits

Oracle APEX

Oracle APEX is the most popular low-code development platform that enables you to build enterprise apps 20x faster with 100x less code. APEX lets developers quickly develop and deploy enterprise-grade apps that are highly secure out of the box.

It is easy to start to develop APEX apps; however, install and configure an APEX environment from scratch can be overwhelming for beginners.

This post will give you the simplicity you are looking to deploy an entire Oracle APEX dev/test environment in your laptop or the cloud using Docker.

Another day I will make a post about Oracle APEX In-depth but now let focus on deployment.

Before anything else, let's see all the options we have to deploy Oracle APEX.

Deployments	PROs	CONs	How to get started
apex free workspace	Easy to use to start testing APEX and to make a concept of proof in APEX.	- Not for commercial apps - No direct access to the database - Not all the features of a full APEX Development Environment	Request a service here
Oracle APEX VM Image	Easy to have a full APEX Development in your laptop if you like VMs.	- VMs can be overwhelming - VM is pre-configured and not tuned for all APEX capabilities	Download the VM here
Oracle APEX On-Premises	The best option to consider if you want a full APEX Development Environment with all the features in your laptop or Cloud.	It's not that easy to set up than other options	keep reading
Oracle Autonomous Database	The best option for Cloud hosting for APEX.	There are restrictions and Limitations for APEX with Autonomous Database, see the entire list here	Start your Oracle Cloud journey right away here

Prerequisites

Before starting, you need the following:

Docker Engine

You can install Docker Desktop on your laptop here

If you are using Linux, you can install Docker Engine here
This guide requires docker-compose. If you don’t have it yet, take a look at the installation instructions and get it.

If you’re installing docker-compose on CoreOS, it needs to go into /opt/bin instead of /usr/local/bin.
At least 20G of disk space and 4G of memory is recommended.
An internet connection.

The Setup

First of all, let download or clone the GitHub repository that accompanies this guide.

git clone https://github.com/reybis/oracle-apex-docker-stack.git

Due to licensing restrictions, I can’t host the software files in Github or elsewhere. As such, you’ll need to download them manually. Download the following files and store them in the respective software folder.

When you download the repo and all the software files, the directory structure needs to be like the following.

.
.gitignore
LICENSE.md
README.md
docker-compose.yml
preview.gif
ol7_ords
  ├── Dockerfile
  ├── README.md
  ├── scripts
  │   ├── healthcheck.sh
  │   ├── install_os_packages.sh
  │   ├── ords_software_installation.sh
  │   ├── server.xml
  │   └── start.sh
  └── software
      ├── apache-tomcat-9.0.37.tar.gz
      ├── apex_20.1.zip
      ├── OpenJDK11U-jdk_x64_linux_hotspot_11.0.8_10.tar.gz
      ├── ords-20.2.0.178.1804.zip
      ├── put_software_here.txt
      └── sqlcl-20.2.0.174.1557.zip
ol7_19
  ├── Dockerfile
  ├── README.md
  ├── scripts
  │   ├── healthcheck.sh
  │   └── start.sh
  └── software
      ├── apex_20.1.zip
      ├── LINUX.X64_193000_db_home.zip
      └── put_software_here.txt

Oracle APEX Stack Up!

With all the files in place, you can create the stack using the following command.

docker-compose up

If you want to be in detached mode use -d after the up command

The docker-compose command creates the following services:

[DB] - Oracle Enterprise Database with Oracle APEX installed
[ORDS] - ORDS/Tomcat
[PORTAINER] - Portainer to manage the stack

Some things to keep in mind:

The database is created the first time the service DB is started, and also APEX is installed, which means it can take some time to be fully operational.

The DB service expose port 1521.
The ORDS service depends on the DB service.

The ORDS service expose port 8080 and 8443.

The PORTAINER service doesn't create the admin user, you will need to create it manually when access to localhost:9000

The PORTAINER service expose port 9000.
A folder called volumes will be created to persist the database files and ORDS/Tomcat files.

After the docker-compose command succeeded, you can view the stack by accessing portainer at localhost:9000 or by issuing the following command:

docker-compose ps

That's it, now you have an entire Oracle APEX Environment in your machine, and you can access it at localhost:8080.

Oracle APEX Stack Down!

If you are done with your work and want to stop the stack, you can do it with the following command:

docker-compose down

Optional: Custom Setup

If you like to change some environment settings like volumes, passwords, service names for the database, or many others, you can easily change it in the docker-compose file.

Open the docker-compose.yml file and change the environment and volume sections on both services:

ORDS

...
environment:
  - DB_HOSTNAME=db
  - DB_PORT=1521
  - DB_SERVICE=pdb1
  - APEX_PUBLIC_USER_PASSWORD=ApexPassword1
  - APEX_TABLESPACE=APEX
  - TEMP_TABLESPACE=TEMP
  - APEX_LISTENER_PASSWORD=ApexPassword1
  - APEX_REST_PASSWORD=ApexPassword1
  - PUBLIC_PASSWORD=ApexPassword1
  - SYS_PASSWORD=SysPassword1
  - KEYSTORE_PASSWORD=KeystorePassword1
volumes:
  - ./volumes/ol7_19_ords_tomcat:/u01/config/instance1
...

...
environment:
  - SYS_PASSWORD=SysPassword1
  - PDB_PASSWORD=PdbPassword1
  - APEX_EMAIL=me@example.com
  - APEX_PASSWORD=ApexPassword1
volumes:
  - ./volumes/ol7_19_ords_db:/u02
...

Credits

Bunch of ideas from Oracle-base docker files by Tim Hall.

Set up a Kubernetes cluster using microk8s on macOS

Reybis Ceballos — Tue, 18 Aug 2020 18:37:05 +0000

Disclaimer: This post follows a simple approach, there are probably better ways to do this (please share them if you know any!), and your mileage most definitely will vary.

This post is part of a series of posts on how to Set up a Kubernetes cluster on macOS, in this case, using microk8s.

Kubernetes is a complex container orchestration tool that can be overwhelming for beginners. Had you wondered how to get started on Kubernetes by yourself easily without the complexity of Turnkey Solutions (Oracle OKE, AWS EKS) and Managed Solutions (Google GKE), this post would give you the simplicity to deploy a Kubernetes cluster on macOS intended for dev/test purposes.

Microk8s
Prerequisites
Installation
Create the cluster
Test Kubernetes
See the Cluster IP
Deploy a Pod

💠 Microk8s

Enter microk8s, it is the smallest, most straightforward production-grade cluster of K8s. There are no VMs in the middle like other deployments Minikube. Instead, it uses snap packages, snap is an application packaging and isolation technology; microk8s is so small than even you can use it on Raspberry Pi.

Although our goal is to deploy a dev/test environment, microk8s is intended for all 3 environments (production, dev & test). Whether you are running a production environment or interested in exploring K8s, microK8s serves your needs.

☑️ Prerequisites

Before starting, you need these prechecks:

Install the brew package manager.
At least 20G of disk space and 4G of memory is recommended.
An internet connection.

Don't have the brew command? You need to open a terminal and run the following command:

  /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"

⚙️ Installation

In terminal, install microk8s with brew.

brew install ubuntu/microk8s/microk8s

On macOS microk8s need multipass, when prompted say yes.

🧑‍🚀 Create the cluster

To deploy a Kubernetes cluster, you can go with the install command without parameters.
```
microk8s install
```
Or you can be more specific like me (2 CPU, 2GB RAM, 30GB maximum space of disk).
```
microk8s install --cpu 2 --mem 2 --disk 30
```
While it is running, you can open another terminal window and check the installation's status with the following command:
```
microk8s status --wait-ready
```
Enable the DNS service.
```
microk8s enable dns
```

✅ Test Kubernetes

Let's test our command center

  kubectl get nodes

You should see one node named microk8s-vm in status Ready

  NAME          STATUS   ROLES    AGE     VERSION
  microk8s-vm   Ready    <none>   4d19h   v1.18.6-1+64f53401f200a7

🗺️ See the Cluster IP

Run the following command and find the cluster IP in the endpoint property.

  kubectl describe svc kubernetes

  Name:              kubernetes
  Namespace:         default
  Labels:            component=apiserver
                     provider=kubernetes
  Annotations:       <none>
  Selector:          <none>
  Type:              ClusterIP
  IP:                10.152.183.1
  Port:              https  443/TCP
  TargetPort:        16443/TCP
  Endpoints:         192.168.64.4:16443
  Session Affinity:  None
  Events:            <none>

Mine is 192.168.64.4.

🚀 Deploy a Pod

I make a definition file just for you, Time to make a simple cluster:

  kubectl create -f https://raw.githubusercontent.com/reybis/set-up-kubernetes-cluster/master/nginx-deployment.yml

This will create a pod of nginx and one nodePort service at 30005.

Since you know the Cluster IP, you can see your nginx pod http://cluster-ip:30005 deployed on your new local cluster! 🎉

That's it, now you have a Kubernetes cluster in your machine without VMs.

Set up a Kubernetes cluster using Minikube on macOS

Reybis Ceballos — Mon, 17 Aug 2020 17:56:40 +0000

Disclaimer: This post follows a simple approach, there are probably better ways to do this (please share them if you know any!), and your mileage most definitely will vary.

This post is part of a series of posts on how to Set up a Kubernetes cluster on macOS, in this case, using minikube.

Minikube
Prerequisites
Installation
Create the cluster
Test Kubernetes
See the Cluster IP
Deploy a Pod

💠 Minikube

Minikube is a tool that runs a single-node Kubernetes cluster in a virtual machine on your computer, so basically, it wouldn't be for a production environment. Remember, this is for test/dev purposes.

☑️ Prerequisites

Before starting, you need these prechecks:

Check if virtualization is supported on your system
In terminal run the following command, and verify that the output is non-empty:
```
sysctl -a | grep -E --color 'machdep.cpu.features|VMX'
```
If the output is not empty, we can proceed.
An Hypervisor, in macOS you can use hyperkit or Virtualbox.
For this post's goal, we would stay with Virtualbox to maintain simplicity and hence is cross-platform. I'm a big fan of vagrant to make this kind of environment but it would be overwhelming for the tutorial, maybe for another day 😉.
At least 20G of disk space and 4G of memory is recommended.
A system that supports virtualization.
An internet connection.

⚙️ Installation

Open terminal and run the following commands.

Install Minikube with brew.

brew install minikube

Install Minikube without brew.

curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-darwin-amd64 \ && chmod +x minikube
sudo mv minikube /usr/local/bin

Confirm Installation of Minikube.
```
minikube status
```

🧑‍🚀 Create the cluster

To deploy a Kubernetes cluster, just start minikube with the driver parameter set to virtualbox.

  minikube start --driver=virtualbox

Enable the DNS service.

  minikube addons enable kube-dns

✅ Test Kubernetes

Let's test our command center

  kubectl get nodes

You should see one node in status Ready

🗺️ See the Cluster IP

Run the following command and find the cluster IP in the endpoint property.

  kubectl describe svc kubernetes

🚀 Deploy a Pod

I make a definition file just for you, Time to make a simple cluster:

  kubectl create -f https://raw.githubusercontent.com/reybis/tutorial-minikube/master/nginx-deployment.yml

This will create a pod of nginx and one nodePort service at 30005.

Since you know the Cluster IP, you can see your nginx pod http://cluster-ip:30005 deployed on your new local cluster! 🎉

That's it, now you have a Kubernetes cluster in your machine.

Connect to Oracle database using Instant Client macOS

Reybis Ceballos — Mon, 17 Aug 2020 02:36:13 +0000

This post is part of a series of posts on how to Connect to Oracle database on macOS, in this case, using Instant Client on macOS.

We will install and use the Oracle Instant Client, which is one of the easiest and fastest ways to connect to an Oracle database, the Instant Client is practically mandatory for development environments like NodeJS, so let's get started.

Prerequisites
Installation
Connect to Oracle
- Using EZCONNECT
- Using TNSNAMES
- Using Oracle Wallet
- Oracle Autonomous Database

☑️ Prerequisites

Before starting, you must do the following on your Mac.

Temporarily disable macOS security (know how here)
Download the Oracle Instant Client

Download the basic and sqlplus files according to the version of your database from the following link.Example, if you want to connect to an Oracle 19c database, you will need to install:

instantclient-basic-macos.x64-19.3.0.0.0dbru.zip

instantclient-sqlplus-macos.x64-19.3.0.0.0dbru.zip

Important: Oracle Call Interface 19.3 and 18.1 can connect to Oracle database 11.2 or later. If you want to connect to a lower database, you must use version 12.

⚙️ Installation

With the requirements covered, we can start the installation:

Open terminal.
Create the Oracle directory.

  sudo mkdir -p /opt/oracle

Move the downloaded files to the Oracle folder and unzip the files.

  sudo mv instantclient-basic-macos.x64-19.3.0.0.0dbru.zip /opt/oracle/
  sudo mv instantclient-sqlplus-macos.x64-19.3.0.0.0dbru.zip /opt/oracle/
  cd /opt/oracle
  sudo unzip instantclient-basic-macos.x64-19.3.0.0.0dbru.zip
  sudo unzip instantclient-sqlplus-macos.x64-19.3.0.0.0dbru.zip

Create the lib directory on your home and the necessary symbolic links to allow applications to find the Instant Client libraries.

  mkdir ~/lib
  ln -s ~/instantclient_19_3/libclntsh.dylib ~/lib/
  ln -s ~/instantclient_19_3/libclntsh.dylib /usr/local/lib/

Create the environment variables in your profile file.

  echo "export PATH=/opt/oracle/instantclient_19_3:$PATH" > ~/.profile
  echo "export LD_LIBRARY_PATH=/opt/oracle/instantclient_19_3" >> ~/.profile
  source ~/.profile

✅ Connect to Oracle Database

After finishing the installation, we can test the connection to the database using the command sqlplus and one of the methods below.

Using EZCONNECT

The easiest way to connect to a database is by using EZCONNECT syntaxis.

In terminal run the following command.

  sqlplus

Once that connect using the EZCONNECT syntax.

  sqlplus user/password@//myhost.reybis.com:1521/myservicename

Using TNSNAMES

If your need to use TNSNAMES see the next steps.

First, in terminal let's create the TNSNAMES file.

  cd /opt/oracle/instantclient_19_3/network/admin
  sudo vi tnsnames.ora

Use the following template to create your TNSNAMES file.

  myservicename= 
  (DESCRIPTION = 
    (ADDRESS = (PROTOCOL = TCP)(HOST = MYHOST.REYBIS.COM)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = MYSERVICENAME)
    )
  )

Then you can connect using the TNSNAMES syntax.

  sqlplus user/password@myservicename

Using Oracle Wallet

Using Oracle Wallet is the safest way to access an Oracle database, if you have the wallet of your database, you just have to do the following:

  cd /opt/oracle/instantclient_19_3/network/admin
  unzip ~/Downloads/wallet_db.zip
  sqlplus user@mywalletservicename

Oracle Autonomous Database

Oracle Cloud Autonomous databases, by default, use a secure connection with Oracle Wallet to guarantee encryption in data-transit. Oracle only allows us to connect to them using an encrypted connection to Oracle Wallet.

  cd /opt/oracle/instantclient_19_3/network/admin
  unzip ~/Downloads/wallet_atpdb.zip
  sqlplus user/password@atpservice_high
  sqlplus user/password@atpservice_medium
  sqlplus user/password@atpservice_low

That's it! You are all set to connect to an Oracle database from macOS 😃

Now I hope you enough knowledge so that you can please any requirement related to Oracle database.

Disable GateKeeper macOS

Reybis Ceballos — Mon, 17 Aug 2020 02:35:43 +0000

To prevent malware from accessing your Mac, Apple enables GateKeeper by default, only allowing you to install and run applications from the App Store or identified Developers (Adobe, Microsoft, etc.).

For example, with GateKeeper enabled when you run sqlplus the first time, it will show you the following message.

To enable it you must go to the System Preferences and click on Always Allow.

As developers, this can become a problem when using terminal applications, then to be able to install and run all kinds of applications, we need to disable GateKeeper.

Important: Only disables GateKeeper temporarily during a project or work session, not permanently.

Let's begin:

In terminal run the following command.
```
sudo spctl --master-disable
```
To verify that GateKeeper is disabled, go to System Preferences, and you should see the following.

All options are displayed "App Store", "App Store and identified developers" and "Any Site".
Select the Any Site option.

That's it, now you can install and run any application. 😃

If you want to enable GateKeeper back, I will show you how to do it in this link.

Enable GateKeeper macOS

Reybis Ceballos — Mon, 17 Aug 2020 02:35:22 +0000

Have you disabled Gatekeeper on macOS? And want to reset security to system default settings, this post is for you.

Ok, so let's get started.

In this post, we will enable Gatekeeper back again only to allow applications from the App Store or Developers identified by Apple.

In terminal run the following command. ```toml

sudo spctl --master-enable


2. To verify that **Gatekeeper** is enabled, go to System Preferences, and you should see the following.
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/ym35w059gcw2hwaztn9o.png)
   * Only **App Store** and **App Store and identified developers** are displayed.
   * The option **App Store** and the **Identified developers** is selected.

That's it, now **Gatekeeper** is back 😃

If you want to disable **Gatekeeper** again, I show you how to do it **here**.

DEV Community: Reybis Ceballos

Oracle APEX Stack on Docker

Oracle APEX Stack

Oracle APEX

Prerequisites

The Setup

Oracle APEX Stack Up!

Oracle APEX Stack Down!

Optional: Custom Setup

Credits

Set up a Kubernetes cluster using microk8s on macOS

Table of Contents

💠 Microk8s

☑️ Prerequisites

⚙️ Installation

🧑‍🚀 Create the cluster

✅ Test Kubernetes

🗺️ See the Cluster IP

🚀 Deploy a Pod

Set up a Kubernetes cluster using Minikube on macOS

Table of Contents

💠 Minikube

☑️ Prerequisites

⚙️ Installation

🧑‍🚀 Create the cluster

✅ Test Kubernetes

🗺️ See the Cluster IP

🚀 Deploy a Pod

Connect to Oracle database using Instant Client macOS

Table of Contents

☑️ Prerequisites

⚙️ Installation

✅ Connect to Oracle Database

Using EZCONNECT

Using TNSNAMES

Using Oracle Wallet

Oracle Autonomous Database

Disable GateKeeper macOS

Enable GateKeeper macOS