feat: tasks/workflows implemented

Also implemented DependencyGraph, to support the corresponding changes
to dependant calculations.

docs/reference/commands.md

@@ -446,9 +446,9 @@ This is useful for debugging or ad-hoc experimentation with modules.
 
 Examples:
 
-    garden run module my-container           # run an ad-hoc instance of a my-container container and attach to it
-    garden run module my-container /bin/sh   # run an interactive shell in a new my-container container
-    garden run module my-container --i=false /some/script  # execute a script in my-container and return the output
+    garden run module my-container                                   # run an ad-hoc instance of a my-container container and attach to it
+    garden run module my-container /bin/sh                           # run an interactive shell in a new my-container container
+    garden run module my-container --interactive=false /some/script  # execute a script in my-container and return the output
 
 ##### Usage
 
@@ -494,6 +494,32 @@ Examples:
 | -------- | ----- | ---- | ----------- |
   | `--force-build` |  | boolean | Force rebuild of module.
 
+### garden run task
+
+Run a task (in the context of its parent module).
+
+This is useful for re-running tasks on the go, for example after writing/modifying database migrations.
+
+Examples:
+
+    garden run task my-db-migration   # run my-migration
+
+##### Usage
+
+    garden run task <task> [options]
+
+##### Arguments
+
+| Argument | Required | Description |
+| -------- | -------- | ----------- |
+  | `task` | Yes | The name of the task to run.
+
+##### Options
+
+| Argument | Alias | Type | Description |
+| -------- | ----- | ---- | ----------- |
+  | `--force-build` |  | boolean | Force rebuild of module before running.
+
 ### garden run test
 
 Run the specified module test.

docs/reference/config.md

@@ -313,7 +313,8 @@ module:
       # Required.
       name:
 
-      # Names of the services that must be running before the test is run.
+      # The names of any services that must be running, and the names of any tasks that must be
+      # executed, before the test is run.
       #
       # Optional.
       dependencies: 
@@ -444,6 +445,36 @@ module:
   # Optional.
   image:
 
+  # When this field is used, the files or directories specified within are automatically synced
+  # into the running container when they're modified. Additionally, any of this module's services
+  # that define a `hotReloadCommand` will be run with that command instead of the one specified in
+  # their `command` field. Services are only deployed with hot reloading enabled when their names
+  # are passed to the `--hot-reload` option in a call to the `deploy` or `dev` command.
+  #
+  # Optional.
+  hotReload: 
+    # Specify one or more source files or directories to automatically sync into the running
+    # container.
+    #
+    # Required.
+    sync: 
+      - # POSIX-style path of the directory to sync to the target, relative to the module's
+        # top-level directory. Must be a relative path if provided. Defaults to the module's
+        # top-level directory if no value is provided.
+        #
+        # Example: "src"
+        #
+        # Optional.
+        source: .
+
+        # POSIX-style absolute path to sync the directory to inside the container. The root path
+        # (i.e. "/") is not allowed.
+        #
+        # Example: "/app/src"
+        #
+        # Required.
+        target:
+
   # POSIX-style name of Dockerfile, relative to project root. Defaults to $MODULE_ROOT/Dockerfile.
   #
   # Optional.
@@ -463,7 +494,8 @@ module:
       # Required.
       name:
 
-      # The names of services that this service depends on at runtime.
+      # The names of any services that this service depends on at runtime, and the names of any
+      # tasks that should be executed before this service is deployed.
       #
       # Optional.
       dependencies: 
@@ -622,7 +654,8 @@ module:
       # Required.
       name:
 
-      # Names of the services that must be running before the test is run.
+      # The names of any services that must be running, and the names of any tasks that must be
+      # executed, before the test is run.
       #
       # Optional.
       dependencies: 
@@ -646,34 +679,35 @@ module:
       env: 
         {}
 
-  # When this field is used, the files or directories specified within are automatically synced
-  # into the running container when they're modified. Additionally, any of this module's services
-  # that define a `hotReloadCommand` will be run with that command instead of the one specified in
-  # their `command` field. Services are only deployed with hot reloading enabled when their names
-  # are passed to the `--hot-reload` option in a call to the `deploy` or `dev` command.
+  # A list of tasks that can be run from this container module. These can be used as dependencies
+  # for services (executed before the service is deployed) or for other tasks.
   #
   # Optional.
-  hotReload: 
-    # Specify one or more source files or directories to automatically sync into the running
-    # container.
+  tasks: 
+    # The task specification for a generic module.
     #
-    # Required.
-    sync: 
-      - # POSIX-style path of the directory to sync to the target, relative to the module's
-        # top-level directory. Must be a relative path if provided. Defaults to the module's
-        # top-level directory if no value is provided.
-        #
-        # Example: "src"
-        #
-        # Optional.
-        source: .
+    # Optional.
+    - # The name of the task.
+      #
+      # Required.
+      name:
 
-        # POSIX-style absolute path to sync the directory to inside the container. The root path
-        # (i.e. "/") is not allowed.
-        #
-        # Example: "/app/src"
-        #
-        # Required.
-        target:
+      # The names of any tasks that must be executed, and the names of any services that must be
+      # running, before this task is executed.
+      #
+      # Optional.
+      dependencies: 
+        -
+
+      # Maximum duration (in seconds) of the task's execution.
+      #
+      # Optional.
+      timeout: null
+
+      # The command that the task should run inside the container.
+      #
+      # Optional.
+      command: 
+        -
 ```
 

examples/hello-world/.garden/local-config.yml

@@ -1,5 +0,0 @@
-kubernetes:
-  previous-usernames:
-    - hello
-linkedModuleSources: []
-linkedProjectSources: []

examples/tasks/garden.yml

@@ -0,0 +1,6 @@
+project:
+  name: tasks
+  environments:
+    - name: local
+      providers:
+        - name: local-kubernetes

examples/tasks/hello-service/.dockerignore

@@ -0,0 +1,4 @@
+node_modules
+Dockerfile
+garden.yml
+app.yaml

examples/tasks/hello-service/Dockerfile

@@ -0,0 +1,13 @@
+FROM node:9-alpine
+
+ENV PORT=8080
+EXPOSE ${PORT}
+WORKDIR /app
+
+ADD package.json /app
+RUN npm install knex -g
+RUN npm install
+
+ADD . /app
+
+CMD ["npm", "start"]

examples/tasks/hello-service/app.js

@@ -0,0 +1,25 @@
+const express = require("express")
+const knex = require("knex")({
+  client: "postgresql",
+  connection: {
+    host: "postgres-service",
+    port: 5432,
+    database: "postgres",
+    user: "postgres",
+  },
+  pool: {
+    min: 4,
+    max: 10
+  },
+})
+
+const app = express();
+
+app.get("/hello", (req, res) => {
+  knex.select("name").from("users")
+    .then((rows) => {
+      res.send(`Hello from Node! Usernames: ${rows.map(r => r.name).join(', ')}`)
+    })
+});
+
+module.exports = { app }

examples/tasks/hello-service/garden.yml

@@ -0,0 +1,24 @@
+module:
+  name: hello-service
+  description: Greeting service
+  type: container
+  services:
+    - name: hello-service
+      command: [npm, start]
+      ports:
+        - name: http
+          containerPort: 8080
+      ingresses:
+        - path: /hello
+          port: http
+      dependencies:
+        - node-migration
+  tests:
+    - name: unit
+      command: [npm, test]
+  tasks:
+    - name: node-migration
+      # sleep to give postgres time to get ready
+      command: ["sleep 5 && knex migrate:latest"]
+      dependencies:
+        - postgres-service

examples/tasks/hello-service/knexfile.js

@@ -0,0 +1,18 @@
+module.exports = {
+  development: {
+    client: "postgresql",
+    connection: {
+      host: "postgres-service",
+      port: 5432,
+      database: "postgres",
+      user: "postgres",
+    },
+    pool: {
+      min: 4,
+      max: 10
+    },
+    migrations: {
+      tableName: "knex_migrations"
+    }
+  }
+}

examples/tasks/hello-service/main.js

@@ -0,0 +1,3 @@
+const { app } = require('./app');
+
+app.listen(process.env.PORT, '0.0.0.0', () => console.log('Node service started'));

examples/tasks/hello-service/migrations/20181008125224_create_users_table.js

@@ -0,0 +1,13 @@
+
+exports.up = function(knex) {
+  return knex.schema.createTable("users", function(t) {
+    t.increments("id").unsigned().primary();
+    t.dateTime("created_at").notNull();
+    t.dateTime("updated_at").nullable();
+    t.string("name").notNull();
+  });
+};
+
+exports.down = function(knex) {
+  return knex.schema.dropTable("users");
+};