test: minimal amazon-ebs test

test/README.md

@@ -6,3 +6,38 @@ results are expected.
 
 Tests are run using [Bats](https://github.com/sstephenson/bats), and therefore
 Bash is required to run any tests.
+
+**Warning:** Many of these tests run using AWS, and therefore have a
+real-world cost associated with running the tests. Be aware of that prior
+to running the tests. Additionally, many tests will leave left-over artifacts
+(AMIs) that you'll have to manually clean up.
+
+## Required Software
+
+Before running the tests, you'll need the following installed. If you're
+running on Mac OS X, most of these are available with `brew`:
+
+* [Bats](https://github.com/sstephenson/bats)
+
+* [AWS cli](http://aws.amazon.com/cli/)
+* [jq](http://stedolan.github.io/jq/)
+
+## Configuring Tests
+
+**For tests that require AWS credentials:**
+
+Set the following self-explanatory environmental variables:
+
+* `AWS_ACCESS_KEY_ID`
+* `AWS_SECRET_ACCESS_KEY`
+
+## Running Tests
+
+These tests are meant to be run _one file at a time_. There are some
+test files (such as the amazon-chroot builder test) that simply won't
+run except in special environments, so running all test files will probably
+never work.
+
+If you're working on Packer and want to test that your change didn't
+adversely affect something, try running only the test that is related to
+your change.

test/builder_amazon_ebs.bats

+#!/usr/bin/env bats
+#
+# This tests the amazon-ebs builder. The teardown function will automatically
+# delete any AMIs with a tag of `packer-test` being equal to "true" so
+# be sure any test cases set this.
+
+load test_helper
+fixtures amazon-ebs
+
+teardown() {
+    aws ec2 describe-images --owners self --output json --filters 'Name=tag:packer-test,Values=true' \
+        | jq -r -M '.Images[]["ImageId"]'
+        | xargs -n1 aws ec2 deregister-image --image-id
+}
+
+@test "build minimal.json" {
+    run packer build $FIXTURE_ROOT/minimal.json
+    [ "$status" -eq 0 ]
+}

test/fixtures/amazon-ebs/minimal.json

+{
+    "builders": [{
+        "type": "amazon-ebs",
+        "ami_name": "packer-test {{timestamp}}",
+        "instance_type": "m1.small",
+        "region": "us-east-1",
+        "ssh_username": "ubuntu",
+        "source_ami": "ami-0568456c",
+        "tags": {
+            "packer-test": "true"
+        }
+    }]
+}

test/test_helper.bash

+# Let's verify that the tools we need are installed
+declare -a required=(aws jq)
+for cmd in "${required[@]}"; do
+    command -v $cmd >/dev/null 2>&1 || {
+        echo "'$cmd' must be installed" >&2
+        exit 1
+    }
+done
+
+# This sets the directory for fixtures by specifying the name of
+# the folder with fixtures.
+fixtures() {
+    FIXTURE_ROOT="$BATS_TEST_DIRNAME/fixtures/$1"
+}
+
+# This allows us to override a function in Bash
+save_function() {
+    local ORIG_FUNC=$(declare -f $1)
+    local NEWNAME_FUNC="$2${ORIG_FUNC#$1}"
+    eval "$NEWNAME_FUNC"
+}
+
+# Override the run function so that we always output the output
+save_function run old_run
+run() {
+    old_run $@
+
+    # "$output" gets rid of newlines. This will bring them back.
+    for line in "${lines[@]}"; do
+        echo $line
+    done
+}