Total newbie question... There is a lot in the documentation about how to configure behavior for a given environment. And the output from pakyow help server indicates that the environment can be set to something other than the default. But how (and where) are such defaults set? Should this be done via app.default_environment, and if so, where would that go? The configure block in app/setup.rb?
Note that I'll be happy to submit an update to the docs that adds the answer to this question.
To start the server in a given mode, say development
Just do
bundle exec pakyow server 'development'
https://www.pakyow.org/docs/tools
From my understanding, the default environment can be set on the app object in a configure block in setup.rb
app.default_environment (development)
This configuration option is used to set the default environment.
The environment you set using the app.default_environment specifies the mode the server the defaults to.
Here's an example of a configure block.
configure :development do
# put your development config here
end
And for production replace :development with :production
Here's an example for how you would set the default environment
Pakyow::App.define do
configure do
app.default_environment = :test
end
end
If you do not specify which environment to use as the default, it defaults to :development.
App is just one of the things you can configure to find out how to configure other things, such as Server, Logger, Presenter, Realtime refer to the Docs here at https://www.pakyow.org/docs/config
Environment variables can be set in the .env file
Example .env file contents
SESSION_SECRET=8ac762ca808a8f3151b69d53fc6e2f5efbe46926472695a7cf23514c29cb5ce19ae434e80c96caac1009754cda605c678dba602608708e886447f7b059567645
REDIS_URL=redis://127.0.0.1:6379
The environment variables can be accessed like this in setup.rb
ENV['REDIS_URL']
And you can set it to the variable like so
redis_url = ENV['REDIS_URL']
or you set it to the app object like so for it to be available anywhere in the project
app.redis = ENV['REDIS_URL']
And you can now access the the environment variable anywhere in the project by doing this
Pakyow::Config.app.redis
Hope that helps!
Related
I'm revisiting a project which hasn't been updated for a while.
In production/online environment, it uses environment variables defined at:
openshift online console > applications > deployments > my node app > environment
In development/offline environment, it uses environment variables defined at:
./src/js/my_modules/local_settings (this file is ignored by .gitignore)
The code looks something like:
// check which environment we are in
if (process.env.MONGODB_USER) {
var online_status = "online";
}
else {
var online_status = "offline";
}
// if online, use environment variables defined in red hat openshift
if (online_status === 'online') {
var site_title = process.env.SITE_TITLE;
var site_description = process.env.SITE_DESCRIPTION;
//etc
}
// if offline, get settings from a local file
else if (online_status === 'offline') {
var local_settings = require('./src/js/my_modules/local_settings');
var site_title = local_settings.SITE_TITLE;
var site_description = local_settings.SITE_DESCRIPTION;
// etc
}
I would like to install the dotenv package in my local project repo via:
npm install dotenv
So that I can:
Have my local settings in a .env file in the root of my project (ignored in .gitignore)
Be able to use process.env.SOME_VARIABLE rather than local_settings.SOME_VARIABLE
Get rid of some if/else blocks as both scenarios would point to process.env.SOME_VARIABLE
I'm a bit confused as to how this would effect the online environment.
Seeing as both production/online and development/offline environments would use:
var some_variable = process.env.SOME_VARIABLE_HERE
would the application automatically know to:
Look at the local .env file when in development?
Look at the Red Hat environment variables when in production?
And would adding the required instantiation at the beginning of the server-side file:
require('dotenv').config()
somehow make Red Hat OpenShift freak out (as it seems to already have its own 'things' in place to resolve references to process.env.SOME_VARIABLE_HERE to the relevant values defined in the OpenShift console)?
To have a file by any environment (.dev .staging .prod) into the source code repository or manually in the server (it those are in .gitignore) worked for long time, but now it goes against to the devops.
The clean way is to use environment variables but managed remotely and obtained at the start of your application.
How it works?
Basically your apps don't read or need a file (.env .properties, etc) with variables anymore. It loads them from a remote http service.
Not intrusive
In this approach, you don't need specific languages variables (nodejs in your case). You just need to prepare your app to use environment variables. Your application don't care where the variables come from, just needs to be available at operative system level.
To achieve that, you just need to download the variables using a simple shell code or a very basic algorithm (http invocation) in your favorite language.
After that, after the start of your app, variables are ready to use at the most basic level.
var site_title = process.env.SITE_TITLE;
This approach is not intrusive because your app don't need something complex like library or algorithm in some programing language. Just needs the environment variables.
Intrusive
Same as previous alternative but instead to read the variables direct from environment system, you should use or create a class/module in your language. This offer your the variables you need:
var site_title = VariablesManager.getProperty("SITE_TITLE");
VariablesManager at the startup must have consumed the variables from a remote service (http) and the store them to offer them to whoever needs it through getProperty method.
Also this VariablesManager usually has a feature called hot-reload which at intervals, update the variables consuming the remote variables manager. With this, if your application is running in production with real users and some variable needs to be updated, you just need to change it in the variables manager. Automatically your app will load the new values, without restart or touching your app
This approach is intrusive because you need to load advanced libraries in some programing language or create it.
Devops
Your application just needs a few properties or settings related to the consume of remote variables. For example: variables of acme-web-staging:
remote_variables_manager = https://variables.com/api
application_id = acme-web-staging
secure_key = *****
You could hide the secure key and parametrize the application_id using environment variables (created in the platform console)
remote_variables_manager = https://variables.com/api
application_id = ${application_id}
secure_key = ${remote_variables_manager_key}
Or if you want one variable manager by each environment
staging
remote_variables_manager = https://variables-staging.com/api
application_id = acme-web
secure_key = *****
production
remote_variables_manager = https://variables-staging.com/api
application_id = acme-web
secure_key = *****
Variables manager
This concept was introduced many years ago. I used with java. It consist in a web application with features like:
secure login
create applications
create variables of an application
crypt sensitive values
publish http endpoints to download or query the variables by application
Here a list of some ready to use alternatives:
Configurator
Nodejs & mysql solution. I developed this and I use it in various projects.
Doppler
zookeeper
http://www.therore.net/java/2015/05/03/distributed-configuration-with-zookeeper-curator-and-spring-cloud-config.html
Spring Cloud
https://www.baeldung.com/spring-cloud-configuration
This is a java spring framework functionality in which you can create properties file with configurations and configure your applications to read them.
Consul
Consul is a service mesh solution providing a full featured control plane with service discovery, configuration, and segmentation functionality.
doozerd, etcd
In your specific case
Don't use dot-env
Use pure process.env.foo
Deploy a remote variables manager in your openshift infraestructure
Create just one variable in your openshift web console: APP_ENVIRONMENT
In your code at the start, do something like this:
if (process.env.APP_ENVIRONMENT === "PROD")
//get variables from remote service using
//some http client like axios, request, etc
//then inject them to your process.env
process.env.site_url = remoteVariables.site_url
else
//we are in local developer workspace
//so, nothing complex is required
//developer should inject manually
//before the startup: npm run start or dev
//export site_url = "acme.com"
If you can configure an execution of a shell script before the start of your openshift app, you could load and expose the variables at that stage and the previous snippet would not be necessary because the variables will be ready to be retrieved using process.env directly in your app
Suppose I have a .env file like these:
#dev variable
PORT=3000
#production
PORT=3030
And I get these variables using process.env, how can I manage to sometimes use the dev variable and other times the Production variable
You can create multiple .env files like .dev.env, .prod.env, and load them based on NODE_ENV. using this
Storing configuration in environment variables is the way to go, and exactly what is recommended by the config in the 12-Factor App, so you're already starting with the right foot.
The values of these variables should not be stored with the code, except maybe the ones for your local development environment, which you can even assume as the default values:
port = process.env.PORT || '3000';
For all other environments, the values should be stored in a safe place like Vault or AWS Secrets Manager, and then are only handled by your deployment pipeline. Jenkins, for example, has a credentials plugin to handle that.
Actually I have a nodejs express app with its config file for params like host, port, JWT token, DB params and more.
The question is if it could have sense to keep those params directly on environment variables (whitout any config file) and acces them without the need of do the "require" for config in all components and modules.
All examples I see uses a config file, probably something about security or memory?
config file is usually for setting the default values for your environment variables,
which is needed when you are writing the test cases and need to use default values or mock values,
and also you will have all the env variables at one place which is better management.
so if you have an environment variable x,
in config file you can keep it as
config.x = process.env.x || 'defaultVale or mockValue'
A config file lets your very quickly set the entire environment of a machine - eg S3 buckets, API urls, access keys, etc. If you separate these into separate process.env.VARIABLE then you would need to set each of these...for which you would likely make a script...and now you have an environment file again!
To access environment variables you can use process.env.VARIABLE in your nodejs code (is always a string), as long as the variable is set before the process is started.
Another possibility is using an .env files in nodejs. I think you have to npm install dotenv in your application. Ideally different instances (dev, prod....) have its own .env file, and you dont have to call require("dotenv") every time if you want to access the environment variable. Call it in the very beginning i.e) in app.js and you can access the environment variable in any of the sub-files.
I have a react app (CRA) it will be running inside a docker container for which I will set an environment variable "API_KEY" = "some_value". For the example of windows this is System Properties -> Environment Variables -> System Variables -> Variable = "API_KEY" and Value = "some_value".
I would like to access to get this variable into the application at run time. This is for the API_KEY for Azure App Insights.
https://learn.microsoft.com/en-us/azure/application-insights/app-insights-javascript#add-the-sdk-script-to-your-app-or-web-pages
The above link shows the <your instrumentation key>. I will be deploying the same application to multiple environments. Each instance of the application will need to use its specific App Insights. So the goal here is to specify that API_KEY in the environment variables which will be different for each of the docker containers.
Please note I am aware of nodeJs and process.env.API_KEY but this does not read from the systems environment variables. Is there a way to get the system variable to link up to the process.env for the node instance?
-PS this request is to an API service that will need to fire straight away. So making an API request to get it is out of the question. It will be exposed to the end client as it is logging JavaScript events for each client.
The answer is NO. You can not read system environment variables. You can however set process environment variables in a *.env file. In my case I will generate this env file via a shell script which will be triggered by the Dockerfile. This will then scrap the process for it's environment variables that start with "REACT_APP_#".
Hope this helps others.
Generating shell script
https://medium.com/#vietgoeswest/passing-env-variables-from-the-server-to-your-create-react-app-c87578a45358
Setting up env with CRA
https://medium.com/#tacomanator/environments-with-create-react-app-7b645312c09d
Dockerizing a Node.js web app
https://nodejs.org/en/docs/guides/nodejs-docker-webapp/
Passing environment variables from Docker to Node https://medium.com/#felipedutratine/pass-environment-variables-from-docker-to-my-nodejs-or-golang-app-a1f2ddec31f5
Also helpful
https://github.com/facebook/create-react-app/issues/982
I'm trying to use the node-config module to change some parameters of my configuration (basically logging level) during runtime.
In the official documentation says:
Environment variables can be used to override file configurations. Any environment variable that starts with $CONFIG_ is set into the CONFIG object.
I've checked that this is true when the server starts but it does not seem to work once it's up. (The handler of the watch function is never called when an environment variable is changed unlike a change in the runtime.json file or directly changing a config variable).
I'm currently watching the whole CONFIG object like this:
var CONFIG = require('config');
CONFIG.watch( CONFIG , null , function(object, propertyName, priorValue, newValue){
console.log("Configuration change detected");
});
Does anyone know if this is possible?
The environment is available during startup of a process.
If the process is running, you won't be able to change the environment anymore, the process is in.
The only option is to restart the process or use other mechanisms to communicate with it.
Say for example having a rest or tcp listener inside, where you can transfer your variable inside.
Best regards
Robert
As you must knowing, React is a single page application which is eventually when it is complied is a static page app that means all the files of the react application is complied into vanilla JS and CSS file bundle in a Tarball. Now that Tarball is eventually deployed on a web server. It could be Apache web server, nginx web server or anything which you are using it but an important point is the static app is running in someone else browser and someone access to website CSS and JS are downloaded in a browser and it is running in the browser runtime environment so technically you cannot have a runtime environment variable for someone else browser but may be there would be a way to access them during runtime.
SOLUTION
I have achieved this goal with the package called runtime-cra.
follow the steps on this official documentation: https://blog.risingstack.com/create-react-app-runtime-env-cra/