This is a basic Hello World Encore application with a single API endpoint and a PostgreSQL database to keep track of how many times you've said hello.
When you have installed Encore, you can create a new Encore application and clone this example with this command.
encore app create my-app-name --example=sql-database
In this starter app there is already a database defined, but let's take this opportunity to learn a bit about how Encore helps you create and use databases.
Encore treats SQL databases as logical resources and natively supports PostgreSQL databases.
To create a database, import encore.dev/storage/sqldb and call sqldb.NewDatabase, assigning the result to a package-level variable.
Databases must be created from within an Encore service.
For example:
todo/db.gotodo/migrations/1_create_table.up.sqlpackage todo
// Create the todo database and assign it to the "tododb" variable
var tododb = sqldb.NewDatabase("todo", sqldb.DatabaseConfig{
Migrations: "./migrations",
})
// Then, query the database using db.QueryRow, db.Exec, etc.
As seen above, the sqldb.DatabaseConfig specifies the directory containing the database migration files,
which is how you define the database schema.
See the Defining the database schema section below for more details.
With this code in place Encore will automatically create the database when starting encore run (locally)
or on the next deployment (in the cloud). Encore automatically injects the appropriate configuration to authenticate
and connect to the database, so once the application starts up the database is ready to be used.
Database schemas are defined by creating migration files in a directory named migrations
within an Encore service package. Each migration file is named <number>_<name>.up.sql, where
<number> is a sequence number for ordering the migrations and <name> is a
descriptive name of what the migration does.
On disk it might look like this:
/my-app
├── encore.app // ... and other top-level project files
│
└── todo // todo service (a Go package)
├── migrations // todo service db migrations (directory)
│ ├── 1_create_table.up.sql // todo service db migration
│ └── 2_add_field.up.sql // todo service db migration
├── todo.go // todo service code
└── todo_test.go // tests for todo service
Each migration runs in order and expresses the change in the database schema from the previous migration.
The file name format is important. Migration files must be sequentially named, starting with 1_ and counting up for each migration.
Each file name must also end with .up.sql.
The first migration usually defines the initial table structure. For example,
a todo service might start out by creating todo/migrations/1_create_table.up.sql with
the following contents:
CREATE TABLE todo_item (
id BIGSERIAL PRIMARY KEY,
title TEXT NOT NULL,
done BOOLEAN NOT NULL DEFAULT false
);
To run the application locally, make sure you have Docker installed and running. This is required to run Encore applications with SQL databases.
encore run
To see that your app is running, you can ping the API.
curl http://localhost:4000/hello/There
While encore run is running, open http://localhost:9400/ to access Encore's local developer dashboard.
Here you can see traces for all requests that you made while using the frontend, see your architecture diagram, and view API documentation in the Service Catalog.
You can connect to your databases via psql shell:
encore db shell <database-name> --env=local --superuser
Learn more in the CLI docs.
See the self-hosting instructions for how to use encore build docker to create a Docker image and configure it.
Deploy your application to a free staging environment in Encore's development cloud using git push encore:
git add -A .
git commit -m 'Commit message'
git push encore
You can also open your app in the Cloud Dashboard to integrate with GitHub, or connect your AWS/GCP account, enabling Encore to automatically handle cloud deployments for you.
Follow these steps to link your app to GitHub:
encore test ./...