Vapor 3 Sessions with PostgreSQL example

1_configure.swift

import FluentPostgreSQL
import Vapor

public func configure(_ config: inout Config, _ env: inout Environment, _ services: inout Services) throws {    
    // (1) Standard PostgreSQL setup
    try services.register(FluentPostgreSQLProvider())

    let pgURL = Environment.get("DATABASE_URL") ?? "postgres://vapor:vapor@127.0.0.1:5432/vapor"
    let pgConfig = PostgreSQLDatabaseConfig(url: pgURL)!

    var databases = DatabasesConfig()
    databases.add(database: PostgreSQLDatabase(config: pgConfig), as: .psql)
    services.register(databases)
    // --- (1) END

    var middlewares = MiddlewareConfig()
    middlewares.use(ErrorMiddleware.self)
    middlewares.use(SessionsMiddleware.self) // (2) Enabling sessions
    services.register(middlewares)

    var migrations = MigrationConfig()
    migrations.prepareCache(for: .psql) // (3) Adding CacheEntry to the migrations
    services.register(migrations)

    // (4) Configuring FluentPostgreSQL as KeyedCache service...
    //         ...like scratching your ear from behind your back
    services.register(KeyedCache.self) { container in
        try container.keyedCache(for: .psql)
    }

    config.prefer(DatabaseKeyedCache<ConfiguredDatabase<PostgreSQLDatabase>>.self, for: KeyedCache.self)
    // --- (4) END
  
    let router = EngineRouter.default()
    try routes(router)
    services.register(router, as: Router.self)
}

2_routes.swift

import Vapor

public func routes(_ router: Router) throws {
    router.get("hello") { req -> String in
        let name: String = try req.session()["name"] ?? "World"
        return "Hello, \(name)!\n"
    }

    router.post("hello") { req -> Response in
        guard let name: String = try req.content.syncGet(at: "name") else {
            throw Abort(.badRequest)
        }

        let session = try req.session()
        session["name"] = name
        return req.redirect(to: "/hello")
    }
}

3_test.sh

# cleaning up...
rm cookiejar

# 1. creating a new session
curl localhost:8080/hello -c cookiejar -b cookiejar
# prints "Hello, World!"

# 2. updating name in the session
curl -d name=Zsolt localhost:8080/hello -L -c cookiejar -b cookiejar
# prints "Hello, Zsolt!"

# 3. restarting the server
# ... this one is up to the reader of the gist ...

# 4. verifying session still exists
curl localhost:8080/hello -c cookiejar -b cookiejar
# prints "Hello, Zsolt!" again :)