Go tutorial and reference

docs/reference/extensions/go-framework.rst

@@ -0,0 +1,71 @@
+.. _go-framework-reference:
+
+go-framework
+----------------
+
+The Go extension streamlines the process of building Go application
+rocks.
+
+The extension builds and copies the Go binary file to the rock.
+By default, the base ``bare`` is used, to generate a lightweight image.
+
+
+.. note::
+    The Go extension is compatible with the ``bare`` and ``[email protected]``
+    bases.
+
+Project requirements
+====================
+
+To use the ``go-framework`` extension, there must be a ``go.mod`` file
+in the root directory of the project.
+
+
+``parts`` > ``go-framework/install-app`` > ``organize``
+=========================================================
+
+If the main package is in the base directory and the rockcraft name
+attribute is equal to the go module name, the name of the binary will
+be selected correctly, otherwise you will need to adjust it.
+
+You can use this field to specify a different binary to be used as the
+main application, without having to override the service command. For example,
+if your Go application contains a ``main`` package in the directory
+``cmd/anotherserver``, the name of the binary will be ``anotherserver``
+and you can override the main application to use the binary with the
+next snippet:
+
+.. code-block:: yaml
+
+  parts:
+    go-framework/install-app:
+     organize:
+       bin/anotherserver: usr/local/bin/<rockcraft project name>
+
+
+``parts`` > ``go-framework/assets`` > ``stage``
+=========================================================
+
+
+Some files, if they exist in the project root, are included by
+default in the rock in the ``/app`` directory.  These include:
+``migrate``, ``migrate.sh``, ``templates/`` and ``static/``.
+
+You can customise the files to include by overriding the ``stage`` property
+of the ``go-framework/assets`` part:
+
+.. code-block:: yaml
+
+  parts:
+    go-framework/assets:
+      stage:
+        - app/migrate
+        - app/migrate.sh
+        - app/static
+        - app/another_file_or_directory
+
+
+Useful links
+============
+
+- :ref:`build-a-rock-for-a-go-application`

docs/reference/extensions/index.rst

@@ -14,3 +14,4 @@ initiating a new rock.
    flask-framework
    django-framework
    fastapi-framework
+   go-framework

docs/reuse/tutorial/code/task.yaml

@@ -16,3 +16,11 @@ execute: |
   # [docs:install-docker]
   sudo snap install docker
   # [docs:install-docker-end]
+
+  # [docs:docker-regular-user]
+  sudo addgroup --system docker
+  sudo adduser $USER docker
+  newgrp docker
+  sudo snap disable docker
+  sudo snap enable docker
+  # [docs:docker-regular-user-end]

docs/reuse/tutorial/setup.rst

@@ -1,5 +1,5 @@
-We recommend starting from a clean Ubuntu 22.04 installation. If you don't have
-one available, you can create one using `Multipass`_:
+We recommend starting from a clean Ubuntu installation. If we don't have
+one available, we can create one using `Multipass`_:
 
 .. tabs::
 
@@ -11,9 +11,9 @@ one available, you can create one using `Multipass`_:
 
             snap services multipass
 
-        If you see the ``multipass`` service but it isn't "active", then you'll
-        need to run ``sudo snap start multipass``. On the other hand, if you get
-        an error saying ``snap "multipass" not found``, then you must install
+        If we see the ``multipass`` service but it isn't "active", then we'll
+        need to run ``sudo snap start multipass``. On the other hand, if we get
+        an error saying ``snap "multipass" not found``, then we must install
         `Multipass <install-multipass_>`_:
 
         .. code-block:: bash
@@ -30,11 +30,11 @@ one available, you can create one using `Multipass`_:
         See `Multipass installation instructions <install-multipass_>`_, switch
         to macOS in the drop down.
 
-Then you can create the VM with the following command:
+Then we can create the VM with the following command:
 
 .. code-block:: text
 
-    multipass launch --disk 10G --name rock-dev 22.04
+    multipass launch --disk 10G --name rock-dev 24.04
 
 Finally, once the VM is up, open a shell into it:
 
@@ -52,31 +52,40 @@ and initialised:
    sudo snap install lxd
    lxd init --auto
 
-In order to create the rock, you'll need to install Rockcraft:
+In order to create the rock, we'll need to install Rockcraft:
 
 .. literalinclude:: /reuse/tutorial/code/task.yaml
     :language: bash
     :start-after: [docs:install-rockcraft]
     :end-before: [docs:install-rockcraft-end]
     :dedent: 2
 
-We'll use Docker to run the rock. You can install it as a ``snap``:
+We'll use Docker to run the rock. We can install it as a ``snap``:
 
 .. literalinclude:: /reuse/tutorial/code/task.yaml
     :language: bash
     :start-after: [docs:install-docker]
     :end-before: [docs:install-docker-end]
     :dedent: 2
 
+By default, Docker is only accessible with root privileges (``sudo``). We want
+to be able to use Docker commands as a regular user:
+
+.. literalinclude:: /reuse/tutorial/code/task.yaml
+    :language: bash
+    :start-after: [docs:docker-regular-user]
+    :end-before: [docs:docker-regular-user-end]
+    :dedent: 2
+
 .. warning::
    There is a `known connectivity issue with LXD and Docker
-   <lxd-docker-connectivity-issue_>`_. If you see a
+   <lxd-docker-connectivity-issue_>`_. If we see a
    networking issue such as "*A network related operation failed in a context
-   of no network access*", make sure you apply one of the fixes suggested
+   of no network access*", make sure to apply one of the suggested fixes
    `here <lxd-docker-connectivity-issue_>`_.
 
-Note that you'll also need a text editor. You can either install one of your
-choice or simply use one of the already existing editors in your Ubuntu
+Note that we'll also need a text editor. We can either install one of our
+choice or simply use one of the already existing editors in the Ubuntu
 environment (like ``vi``).
 
 .. _`lxd-docker-connectivity-issue`: https://documentation.ubuntu.com/lxd/en/latest/howto/network_bridge_firewalld/#prevent-connectivity-issues-with-lxd-and-docker

docs/tutorial/code/go/main.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+)
+
+func helloWorldHandler(w http.ResponseWriter, req *http.Request) {
+	log.Printf("new hello world request")
+	fmt.Fprintln(w, "Hello, world!")
+}
+
+func main() {
+	log.Printf("starting hello world application")
+	http.HandleFunc("/", helloWorldHandler)
+	http.ListenAndServe(":8000", nil)
+}

docs/tutorial/code/go/main.go.time

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+)
+
+func helloWorldHandler(w http.ResponseWriter, req *http.Request) {
+	log.Printf("new hello world request")
+	fmt.Fprintln(w, "Hello, world!")
+}
+
+func timeHandler(w http.ResponseWriter, req *http.Request) {
+	log.Printf("new time request")
+	now := time.Now()
+	fmt.Fprintln(w, now.Format(time.DateTime))
+}
+
+func main() {
+	log.Printf("starting hello world application")
+	http.HandleFunc("/", helloWorldHandler)
+	http.HandleFunc("/time", timeHandler)
+	http.ListenAndServe(":8000", nil)
+}

docs/tutorial/code/go/task.yaml

@@ -0,0 +1,109 @@
+###########################################
+# IMPORTANT
+# Comments matter!
+# The docs use the wrapping comments as
+# markers for including said instructions
+# as snippets in the docs.
+###########################################
+summary: Getting started with Go tutorial
+
+environment:
+
+execute: |
+  set -x
+  # [docs:install-go]
+  sudo snap install go --classic
+  # [docs:install-go-end]
+
+  # [docs:mod-init-go]
+  go mod init go-hello-world
+  # [docs:mod-init-go-end]
+
+  # [docs:go-build]
+  go build .
+  # [docs:go-build-end]
+
+  ./go-hello-world &
+  retry -n 5 --wait 2 curl --fail localhost:8000
+
+  # [docs:curl-go]
+  curl --fail localhost:8000
+  # [docs:curl-go-end]
+
+  kill $!
+
+  # [docs:create-rockcraft-yaml]
+  rockcraft init --profile go-framework
+  # [docs:create-rockcraft-yaml-end]
+  sed -i "s/name: .*/name: go-hello-world/g" rockcraft.yaml
+
+  # [docs:pack]
+  ROCKCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS=true rockcraft pack
+  # [docs:pack-end]
+
+  # [docs:ls-rock]
+  ls *.rock -l --block-size=MB
+  # [docs:ls-rock-end]
+
+  # [docs:skopeo-copy]
+  rockcraft.skopeo --insecure-policy \
+    copy oci-archive:go-hello-world_0.1_amd64.rock \
+    docker-daemon:go-hello-world:0.1
+  # [docs:skopeo-copy-end]
+
+  # [docs:docker-images]
+  docker images go-hello-world:0.1
+  # [docs:docker-images-end]
+
+  # [docs:docker-run]
+  docker run --rm -d -p 8000:8000 \
+    --name go-hello-world go-hello-world:0.1
+  # [docs:docker-run-end]
+
+  retry -n 5 --wait 2 curl --fail localhost:8000
+  # [docs:curl-go-rock]
+  curl --fail localhost:8000
+  # [docs:curl-go-rock-end]
+  [ "$(curl localhost:8000)" = "Hello, world!" ]
+
+  # [docs:get-logs]
+  docker exec go-hello-world pebble logs go
+  # [docs:get-logs-end]
+
+  # [docs:stop-docker]
+  docker stop go-hello-world
+  docker rmi go-hello-world:0.1
+  # [docs:stop-docker-end]
+
+  ## Part 2 of the tutorial
+  sed -i "s/version: .*/version: 0.2/g" rockcraft.yaml
+
+  cp main.go.time main.go
+
+  # [docs:docker-run-update]
+  ROCKCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS=true rockcraft pack
+  rockcraft.skopeo --insecure-policy \
+    copy oci-archive:go-hello-world_0.2_amd64.rock \
+    docker-daemon:go-hello-world:0.2
+  docker images go-hello-world:0.2
+  docker run --rm -d -p 8000:8000 \
+    --name go-hello-world go-hello-world:0.2
+  # [docs:docker-run-update-end]
+  retry -n 5 --wait 2 curl --fail localhost:8000
+
+  # [docs:curl-time]
+  curl --fail localhost:8000/time
+  # [docs:curl-time-end]
+  [ "$(curl localhost:8000/time)" != "Hello, world!" ]
+
+  # [docs:stop-docker-updated]
+  docker stop go-hello-world
+  docker rmi go-hello-world:0.2
+  # [docs:stop-docker-updated-end]
+
+  # [docs:cleanup]
+  # delete all the files created during the tutorial
+  rm go.mod rockcraft.yaml main.go go-hello-world \
+    go-hello-world_0.1_amd64.rock \
+    go-hello-world_0.2_amd64.rock
+  # [docs:cleanup-end]