Using Freemarker Templates

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Ktor includes support for FreeMarker templates through the FreeMarker feature. Initialize the FreeMarker feature with a TemplateLoader:

    install(FreeMarker) {
        templateLoader = ClassTemplateLoader(TheApp::class.java.classLoader, "templates")
    }

This TemplateLoader sets up FreeMarker to look for the template files on the classpath in the “templates” package, relative to the current class path. A basic template looks like this:

This feature is defined in the class io.ktor.freemarker.FreeMarker in the artifact io.ktor:ktor-freemarker:$ktor_version.
dependencies { compile "io.ktor:ktor-freemarker:$ktor_version" }
<project> ... <dependencies> <dependency> <groupId>io.ktor</groupId> <artifactId>ktor-freemarker</artifactId> <version>${ktor.version}</version> </dependency> </dependencies> </project>
<html>
<h2>Hello ${user.name}!</h2>

Your email address is ${user.email}
</html>

With that template in resources/templates it is accessible elsewhere in the the application using the call.respond() method:

    get("/{...}") {
        val user = User("user name", "user@example.com")
        call.respond(FreeMarkerContent("index.ftl", mapOf("user" to user), "e"))
    }