--- title_tag: Creating Docker Images | Learn Pulumi title: "Creating Docker Images" layout: topic date: 2021-09-07T14:06:50-05:00 draft: false description: Use Pulumi and the Docker provider to build Docker images locally. meta_desc: Learn how to use Pulumi and the Docker provider to create Docker images locally in this tutorial. index: 1 estimated_time: 10 meta_image: meta.png authors: - sophia-parafina - laura-santamaria tags: - fundamentals - docker links: - text: Code Repo url: https://github.com/pulumi/tutorial-pulumi-fundamentals --- In this part, we'll create our first Pulumi _resource_. Resources in Pulumi are the basic building blocks of your infrastructure, whether that's a database instance or a compute instance or a specific storage bucket. In Pulumi, _resource providers_ manage your resources. You can group those resources to abstract them (such as a group of compute instances that all have the same configuration and implementation) via component resources. In this case, our resources are going to be Docker containers and images that we build locally using infrastructure as code. Our resource provider is Docker, and we're using {{< langhost >}} as our _language host_, or the executor that compiles the code we write and interprets it for Pulumi. {{% notes type="info" %}} Note that we're only using Docker here to make it easier to learn about Pulumi (mainly because setting up a new account on any of the cloud providers can take some time and can introduce a lot of complexity). Most users are using one of the major cloud providers to build with Pulumi. {{% /notes %}} ## Verify your application Let's explore what app we're deploying on the infrastructure we're creating. Open up the [pulumi/tutorial-pulumi-fundamentals repo](https://github.com/pulumi/tutorial-pulumi-fundamentals). In this repository, there is a `backend` directory, a `frontend` directory, and a `data` directory. Each directory contains a `Dockerfile` that builds the image for that portion of the application. Let's examine the backend `Dockerfile` in `backend/Dockerfile`: ```docker FROM node:14 # Create app directory WORKDIR /usr/src/app COPY ./src/package*.json ./ RUN npm install COPY ./src . RUN npm build EXPOSE 3000 CMD [ "npm", "start" ] ``` This `Dockerfile` copies the REST backend into the Docker filesystem, installs the dependencies, and builds the image. Note that port 3000 must be open on your host machine. {{% notes type="info" %}} For the purposes of this topic, we've already built the images. We are showing the code for the application here just for completeness; you won't actually need to do anything with this code. {{% /notes %}} ## Pull a Docker Image with Pulumi {{% choosable language typescript %}} Before we start writing our Pulumi program, we need to install the right provider. In this case, we want to use the `@pulumi/docker` provider for Node.js, our language host. Let's install the provider now: ```bash cd ../ npm install @pulumi/docker ``` {{% /choosable %}} {{% choosable language python %}} Before we start writing our Pulumi program, we need to install the right provider. In this case, we want to use the `pulumi_docker` provider for Python, our language host. It's always good practice for Python to work inside a virtual environment, or venv, so let's activate our venv and use `pip` to install the provider along with the main Pulumi package: ```bash cd ../ source venv/bin/activate pip3 install pulumi_docker ``` You should see output showing the provider package being installed, just like for any Python package install. Add the package to the `requirements.txt` file by adding `pulumi_docker` on a new line at the end of the file. {{% /choosable %}} {{% choosable language go %}} Before we start writing our Pulumi program, we need to install the right providers. In this case, we just need to add the Docker provider to our `go.mod` and `main.go` files. Change the `go.mod` file so that the `require` section looks like this: ```go require ( github.com/pulumi/pulumi-docker/sdk/v3 v3.6.1 github.com/pulumi/pulumi/sdk/v3 v3.44.2 ) ``` Next, add it to the `import` line in `main.go`: ```go import ( "github.com/pulumi/pulumi/sdk/v3/go/pulumi" "github.com/pulumi/pulumi-docker/sdk/v3/go/docker" ) ``` After making these changes, run `go mod tidy` in your terminal. From here, Pulumi will automatically download and install the necessary Go providers the first time we execute the Pulumi program with `pulumi preview` or `pulumi up`. {{% /choosable %}} {{% choosable language java %}} Before we start writing our Pulumi program, we need to install the right providers. In this case, we want to use the `com.pulumi:docker` provider for Java, our language host. Since we're using Gradle, we'll add it to our build file, and it will get added at build time. Let's modify our `build.gradle` file in the `app/` directory: ```java plugins { id 'application' } repositories { maven { // The google mirror is less flaky than mavenCentral() url("https://maven-central.storage-download.googleapis.com/maven2/") } mavenCentral() mavenLocal() } var pulumiJavaSdkVersion = System.getenv("PULUMI_JAVA_SDK_VERSION") ?: "0.1.0" var pulumiDockerSdkVersion = System.getenv("PULUMI_DOCKER_PROVIDER_SDK_VERSION") ?: "3.2.0" dependencies { implementation "com.pulumi:pulumi:$pulumiJavaSdkVersion" implementation "com.pulumi:docker:$pulumiDockerSdkVersion" } application { mainClass = project.hasProperty("mainClass") ? project.getProperty("mainClass") : 'my_first_app.App' } ``` {{% /choosable %}} {{% choosable language yaml %}} {{% /choosable %}} Back inside your Pulumi program, let's pull your first Docker image. Remember that a Pulumi program is the code that defines the desired state of your infrastructure using a general-purpose programming language. In this case, we're using {{< langhost >}}, so our main file is {{< langfile >}}. Inside your program's {{< langfile >}} file, use any editor to add the following code: {{< chooser language "typescript,python,go,java,yaml" / >}} {{% choosable language typescript %}} ```typescript import * as pulumi from "@pulumi/pulumi"; import * as docker from "@pulumi/docker"; const stack = pulumi.getStack(); // Pull the backend image const backendImageName = "backend"; const backend = new docker.RemoteImage(`${backendImageName}Image`, { name: "pulumi/tutorial-pulumi-fundamentals-backend:latest", }); ``` {{% /choosable %}} {{% choosable language python %}} ```python import os import pulumi import pulumi_docker as docker stack = pulumi.get_stack() # Pull the backend image backend_image_name = "backend" backend = docker.RemoteImage(f"{backend_image_name}_image", name="pulumi/tutorial-pulumi-fundamentals-backend:latest" ) ``` {{% /choosable %}} {{% choosable language go %}} ```go package main import ( "fmt" "github.com/pulumi/pulumi-docker/sdk/v3/go/docker" "github.com/pulumi/pulumi/sdk/v3/go/pulumi" ) func main() { pulumi.Run(func(ctx *pulumi.Context) error { // Pull the backend image backendImageName := "backend" backendImage, err := docker.NewRemoteImage(ctx, fmt.Sprintf("%v-image", backendImageName), &docker.RemoteImageArgs{ Name: pulumi.String("pulumi/tutorial-pulumi-fundamentals-backend:latest"), }) if err != nil { return err } ctx.Export("backendDockerImage", backendImage.Name) return nil }) } ``` {{% /choosable %}} {{% choosable language java %}} ```java package my_first_app; import com.pulumi.Context; import com.pulumi.Pulumi; import com.pulumi.docker.RemoteImage; import com.pulumi.docker.RemoteImageArgs; import java.util.List; public class App { public static void main(String[] args) { Pulumi.run(App::stack); } private static void stack(Context ctx) { final var stackName = ctx.stackName(); // Pull the backend image final String backendImageName = "backend"; final var backendImage = new RemoteImage( backendImageName, RemoteImageArgs.builder() .name(String.format("pulumi/tutorial-pulumi-fundamentals-%s:latest",backendImageName)) .build() ); } } ``` {{% /choosable %}} {{% choosable language yaml %}} ```yaml name: my_first_app runtime: yaml description: A minimal Pulumi YAML program configuration: {} variables: {} resources: # Pull the backend image backend-image: type: docker:index:RemoteImage properties: name: pulumi/tutorial-pulumi-fundamentals-backend:latest outputs: {} ``` {{% /choosable %}} {{% choosable language typescript %}} In this file, we import the main Pulumi package and the Docker provider. Then, we figure out which stack we're operating against, and populate the `stack` variable for later use. When we pull our backend image, we give it a name in our stack as "backendImage" before passing some arguments to the Docker provider. The Docker provider uses the `name` argument to pull a remote image for us to use. Notice that we're mixing in some language constructs in here like string interpolation. With Pulumi, we have access to the full language ecosystem, including built-ins and third-party libraries. Pulumi also has typing support, so you can use the tools in your favorite IDE, like completion, to verify that you're using the correct types for any inputs you're using. Pretty cool! {{% /choosable %}} {{% choosable language python %}} In this file, we import the main Pulumi package and the Docker provider. Then, we figure out which stack we're operating against, and populate the `stack` variable for later use. When we pull our backend image, we give it a name in our stack as "backend_image" before passing some arguments to the Docker provider. The Docker provider uses the `name` argument to pull a remote image for us to use. Notice that we're mixing in some Python constructs in here like f-strings (string interpolation). With Pulumi, we have access to the full language ecosystem, including third-party libraries. Pulumi also has typing support, so you can use the tools in your favorite IDE, like completion, to verify that you're using the correct types for any inputs you're using. Pretty cool! {{% /choosable %}} {{% choosable language go %}} In this file, we import the main Pulumi package and the Docker provider. Then, we pull the backend image, using the `backendImageName` variable and supplying the name of the remote image to pull. The Docker provider uses the `Name` argument to supply the name of the remote image for us to use. The `ctx.Export` statement is only there to satisfy Go's requirement that every variable defined must be referenced elsewhere; we'll end up removing it later. Notice that we're mixing in some language constructs here like `fmt.Sprintf()`. With Pulumi, we have access to the full language ecosystem, including all the functionality found in Go's standard library. Pulumi also has typing support, so you can use the tools in your favorite IDE, like completion, to verify you're using the correct types for any inputs you're using. Pretty cool! {{% /choosable %}} {{% choosable language java %}} In this file, we import the main Pulumi package and the Docker provider. Then, we figure out which stack we're operating against, and populate the `stackName` variable for later use. When we pull our backend image, we give it a name in our stack as "backend" before passing some arguments to the Docker provider. The Docker provider uses the `name` argument to pull a remote image for us to use. Notice that we're mixing in some language constructs in here like `String.format`. With Pulumi, we have access to the full language ecosystem, including third-party libraries. Pulumi also has typing support, so you can use the tools in your favorite IDE, like completion, to verify that you're using the correct types for any inputs you're using. Pretty cool! {{% /choosable %}} {{% choosable language yaml %}} In this file, we're defining a `RemoteImage` resource using the Docker provider. The `properties` are the arguments (or _inputs_ in Pulumi terms) that the resource takes. The Docker provider uses the `name` input to pull a remote image for us to use. {{% /choosable %}} Run `pulumi up`. {{% notes type="info" %}} Note that it make take a bit before you get any output because Docker is doing a lot of work in the background before it connects to Pulumi. Be patient! {{% /notes %}} Pulumi should pull your Docker image. First, though, it gives you a preview of the changes you'll be making to the stack and asks if the changes appear okay to you. You'll need to reply "yes" to the prompt to actually pull the image. After the command finishes, you will see your image if you run the command `docker images` or `docker image ls` (depending on your preference). Let's dig a bit deeper into the code and explore the various Pulumi concepts. Every resource has _inputs_ and _outputs_. Inputs are values that are provided to the resource. Outputs are the resource's properties. Note that Pulumi can't know the output until the resource has completed provisioning as some of those outputs are provided by the provider after everything has loaded, booted, or otherwise has come online. More on outputs later. In our case here, the Docker [`RemoteImage`](/registry/packages/docker/api-docs/remoteimage) resource takes the following inputs: {{% choosable language python %}} - an unnamed string: a name for the resource we are creating - `name`: the name of the remote image to pull down {{% /choosable %}} {{% choosable language typescript %}} - an unnamed string: a name for the resource we are creating - `name`: the name of the remote image to pull down {{% /choosable %}} {{% choosable language go %}} - a Pulumi context: typically represented by the variable `ctx` - an unnamed string: a name for the resource we are creating - `Name`: the name of the remote image to pull down {{% /choosable %}} {{% choosable language java %}} - an unnamed string: a name for the resource we are creating - `name`: the name of the remote image to pull down {{% /choosable %}} {{% choosable language yaml %}} - `name`: the name of the remote image to pull down {{% /choosable %}} Now that we've provisioned our first piece of infrastructure, let's add the other pieces of our application. ## Add the frontend client and MongoDB Our application includes a frontend client and MongoDB. We'll add them to the program, so add this code after the previous fragment. {{< chooser language "typescript,python,go,java,yaml" / >}} {{% choosable language typescript %}} ```typescript // Pull the frontend image const frontendImageName = "frontend"; const frontend = new docker.RemoteImage(`${frontendImageName}Image`, { name: "pulumi/tutorial-pulumi-fundamentals-frontend:latest", }); // Pull the MongoDB image const mongoImage = new docker.RemoteImage("mongoImage", { name: "pulumi/tutorial-pulumi-fundamentals-database-local:latest", }); ``` {{% /choosable %}} {{% choosable language python %}} ```python # Pull the frontend image frontend_image_name = "frontend" frontend = docker.RemoteImage(f"{frontend_image_name}_image", name="pulumi/tutorial-pulumi-fundamentals-frontend:latest" ) # Pull the MongoDB image mongo_image = docker.RemoteImage("mongo_image", name="pulumi/tutorial-pulumi-fundamentals-database-local:latest" ) ``` {{% /choosable %}} {{% choosable language go %}} Add this code at the bottom of your program, just before the last `return nil` statement: ```go // Pull the frontend image frontendImageName := "frontend" frontendImage, err := docker.NewRemoteImage(ctx, fmt.Sprintf("%v-image", frontendImageName), &docker.RemoteImageArgs{ Name: pulumi.String("pulumi/tutorial-pulumi-fundamentals-frontend:latest"), }) if err != nil { return err } ctx.Export("frontendDockerImage", frontendImage.Name) // Pull the MongoDB image mongoImage, err := docker.NewRemoteImage(ctx, "mongo-image", &docker.RemoteImageArgs{ Name: pulumi.String("pulumi/tutorial-pulumi-fundamentals-database-local:latest"), }) if err != nil { return err } ctx.Export("mongoDockerImage", mongoImage.Name) ``` {{% /choosable %}} {{% choosable language java %}} ```java // Pull the frontend image final String frontendImageName = "frontend"; final var frontendImage = new RemoteImage( frontendImageName, RemoteImageArgs.builder() .name(String.format("pulumi/tutorial-pulumi-fundamentals-%s:latest",frontendImageName)) .build() ); // Pull the MongoDB image final var mongoImage = new RemoteImage( "mongoImage", RemoteImageArgs.builder() .name("pulumi/tutorial-pulumi-fundamentals-database-local:latest") .build() ); ``` {{% /choosable %}} {{% choosable language yaml %}} ```yaml # Pull the frontend image frontend-image: type: docker:index:RemoteImage properties: name: pulumi/tutorial-pulumi-fundamentals-frontend:latest # Pull the MongoDB image mongo-image: type: docker:index:RemoteImage properties: name: pulumi/tutorial-pulumi-fundamentals-database-local:latest ``` {{% /choosable %}} We pull the frontend client and the populated MongoDB database images the same way we pulled the backend image. Compare your program now to this complete program before we move forward: {{< chooser language "typescript,python,go,java,yaml" / >}} {{% choosable language typescript %}} ```typescript import * as pulumi from "@pulumi/pulumi"; import * as docker from "@pulumi/docker"; const stack = pulumi.getStack(); // Pull the backend image const backendImageName = "backend"; const backend = new docker.RemoteImage(`${backendImageName}Image`, { name: "pulumi/tutorial-pulumi-fundamentals-backend:latest", }); // Pull the frontend image const frontendImageName = "frontend"; const frontend = new docker.RemoteImage(`${frontendImageName}Image`, { name: "pulumi/tutorial-pulumi-fundamentals-frontend:latest", }); // Pull the MongoDB image const mongoImage = new docker.RemoteImage("mongoImage", { name: "pulumi/tutorial-pulumi-fundamentals-database-local:latest", }); ``` {{% /choosable %}} {{% choosable language python %}} ```python import pulumi import pulumi_docker as docker stack = pulumi.get_stack() # Pull the backend image backend_image_name = "backend" backend = docker.RemoteImage(f"{backend_image_name}_image", name="pulumi/tutorial-pulumi-fundamentals-backend:latest" ) # Pull the frontend image frontend_image_name = "frontend" frontend = docker.RemoteImage(f"{frontend_image_name}_image", name="pulumi/tutorial-pulumi-fundamentals-frontend:latest" ) # Pull the MongoDB image mongo_image = docker.RemoteImage("mongo_image", name="pulumi/tutorial-pulumi-fundamentals-database-local:latest" ) ``` {{% /choosable %}} {{% choosable language go %}} ```go package main import ( "fmt" "github.com/pulumi/pulumi-docker/sdk/v3/go/docker" "github.com/pulumi/pulumi/sdk/v3/go/pulumi" ) func main() { pulumi.Run(func(ctx *pulumi.Context) error { // Pull the backend image backendImageName := "backend" backendImage, err := docker.NewRemoteImage(ctx, fmt.Sprintf("%v-image", backendImageName), &docker.RemoteImageArgs{ Name: pulumi.String("pulumi/tutorial-pulumi-fundamentals-backend:latest"), }) if err != nil { return err } ctx.Export("backendDockerImage", backendImage.Name) // Pull the frontend image frontendImageName := "frontend" frontendImage, err := docker.NewRemoteImage(ctx, fmt.Sprintf("%v-image", frontendImageName), &docker.RemoteImageArgs{ Name: pulumi.String("pulumi/tutorial-pulumi-fundamentals-frontend:latest"), }) if err != nil { return err } ctx.Export("frontendDockerImage", frontendImage.Name) // Pull the MongoDB image mongoImage, err := docker.NewRemoteImage(ctx, "mongo-image", &docker.RemoteImageArgs{ Name: pulumi.String("pulumi/tutorial-pulumi-fundamentals-database-local:latest"), }) if err != nil { return err } ctx.Export("mongoDockerImage", mongoImage.Name) return nil }) } ``` {{% /choosable %}} {{% choosable language java %}} ```java package my_first_app; import com.pulumi.Context; import com.pulumi.Pulumi; import com.pulumi.docker.RemoteImage; import com.pulumi.docker.RemoteImageArgs; import java.util.List; public class App { public static void main(String[] args) { Pulumi.run(App::stack); } private static void stack(Context ctx) { final var stackName = ctx.stackName(); // Pull the backend image final String backendImageName = "backend"; final var backendImage = new RemoteImage( backendImageName, RemoteImageArgs.builder() .name(String.format("pulumi/tutorial-pulumi-fundamentals-%s:latest",backendImageName)) .build() ); // Pull the frontend image final String frontendImageName = "frontend"; final var frontendImage = new RemoteImage( frontendImageName, RemoteImageArgs.builder() .name(String.format("pulumi/tutorial-pulumi-fundamentals-%s:latest",frontendImageName)) .build() ); // Pull the MongoDB image final var mongoImage = new RemoteImage( "mongoImage", RemoteImageArgs.builder() .name("pulumi/tutorial-pulumi-fundamentals-database-local:latest") .build() ); } } ``` {{% /choosable %}} {{% choosable language yaml %}} ```yaml name: my_first_app runtime: yaml description: A minimal Pulumi YAML program configuration: {} variables: {} resources: # Pull the backend image backend-image: type: docker:index:RemoteImage properties: name: pulumi/tutorial-pulumi-fundamentals-backend:latest # Pull the frontend image frontend-image: type: docker:index:RemoteImage properties: name: pulumi/tutorial-pulumi-fundamentals-frontend:latest # Pull the MongoDB image mongo-image: type: docker:index:RemoteImage properties: name: pulumi/tutorial-pulumi-fundamentals-database-local:latest outputs: {} ``` {{% /choosable %}} If your code looks the same, great! Otherwise, update yours to match this code. Now, run `pulumi up` to pull all of the images that we'll need. {{% notes type="info" %}} Note that, in the future, you don't need to run `pulumi up` in stages like this to create your infrastructure. You can write the entire program and then run it. We're only doing a step-by-step process here to make learning easier. {{% /notes %}} From here, we can move on to configuring and provisioning our containers. Onward!