Process environment variables defined in compose files (#736)

Reviewed-on: cerc-io/stack-orchestrator#736
Co-authored-by: David Boreham <david@bozemanpass.com>
Co-committed-by: David Boreham <david@bozemanpass.com>

stack_orchestrator/data/compose/docker-compose-test.yml

@@ -5,6 +5,7 @@ services:
     environment:
       CERC_SCRIPT_DEBUG: ${CERC_SCRIPT_DEBUG}
       CERC_TEST_PARAM_1: ${CERC_TEST_PARAM_1:-FAILED}
+      CERC_TEST_PARAM_2: "CERC_TEST_PARAM_2_VALUE"
     volumes:
       - test-data:/data
       - test-config:/config:ro

stack_orchestrator/data/container-build/cerc-test-container/run.sh

@@ -17,6 +17,9 @@ fi
 if [ -n "$CERC_TEST_PARAM_1" ]; then
   echo "Test-param-1: ${CERC_TEST_PARAM_1}"
 fi
+if [ -n "$CERC_TEST_PARAM_2" ]; then
+  echo "Test-param-2: ${CERC_TEST_PARAM_2}"
+fi
 
 if [ -d "/config" ]; then
   echo "/config: EXISTS"

stack_orchestrator/deploy/k8s/cluster_info.py

@@ -22,7 +22,7 @@ from stack_orchestrator.opts import opts
 from stack_orchestrator.util import env_var_map_from_file
 from stack_orchestrator.deploy.k8s.helpers import named_volumes_from_pod_files, volume_mounts_for_service, volumes_for_pod_files
 from stack_orchestrator.deploy.k8s.helpers import get_node_pv_mount_path
-from stack_orchestrator.deploy.k8s.helpers import envs_from_environment_variables_map
+from stack_orchestrator.deploy.k8s.helpers import envs_from_environment_variables_map, envs_from_compose_file, merge_envs
 from stack_orchestrator.deploy.deploy_util import parsed_pod_files_map_from_file_names, images_for_deployment
 from stack_orchestrator.deploy.deploy_types import DeployEnvVars
 from stack_orchestrator.deploy.spec import Spec, Resources, ResourceLimits
@@ -263,6 +263,13 @@ class ClusterInfo:
                     if opts.o.debug:
                         print(f"image: {image}")
                         print(f"service port: {port}")
+                merged_envs = merge_envs(
+                    envs_from_compose_file(
+                        service_info["environment"]), self.environment_variables.map
+                        ) if "environment" in service_info else self.environment_variables.map
+                envs = envs_from_environment_variables_map(merged_envs)
+                if opts.o.debug:
+                    print(f"Merged envs: {envs}")
                 # Re-write the image tag for remote deployment
                 image_to_use = remote_tag_for_image(
                     image, self.spec.get_image_registry()) if self.spec.get_image_registry() is not None else image
@@ -271,7 +278,7 @@ class ClusterInfo:
                     name=container_name,
                     image=image_to_use,
                     image_pull_policy=image_pull_policy,
-                    env=envs_from_environment_variables_map(self.environment_variables.map),
+                    env=envs,
                     ports=[client.V1ContainerPort(container_port=port)],
                     volume_mounts=volume_mounts,
                     resources=to_k8s_resource_requirements(resources),

stack_orchestrator/deploy/k8s/helpers.py

@@ -17,6 +17,7 @@ from kubernetes import client
 import os
 from pathlib import Path
 import subprocess
+import re
 from typing import Set, Mapping, List
 
 from stack_orchestrator.opts import opts
@@ -214,6 +215,33 @@ def _generate_kind_port_mappings(parsed_pod_files):
     )
 
 
+# Note: this makes any duplicate definition in b overwrite a
+def merge_envs(a: Mapping[str, str], b: Mapping[str, str]) -> Mapping[str, str]:
+    result = {**a, **b}
+    return result
+
+
+def _expand_shell_vars(raw_val: str) -> str:
+    # could be: <string> or ${<env-var-name>} or ${<env-var-name>:-<default-value>}
+    # TODO: implement support for variable substitution and default values
+    # if raw_val is like ${<something>} print a warning and substitute an empty string
+    # otherwise return raw_val
+    match = re.search(r"^\$\{(.*)\}$", raw_val)
+    if match:
+        print(f"WARNING: found unimplemented environment variable substitution: {raw_val}")
+    else:
+        return raw_val
+
+
+# TODO: handle the case where the same env var is defined in multiple places
+def envs_from_compose_file(compose_file_envs: Mapping[str, str]) -> Mapping[str, str]:
+    result = {}
+    for env_var, env_val in compose_file_envs.items():
+        expanded_env_val = _expand_shell_vars(env_val)
+        result.update({env_var: expanded_env_val})
+    return result
+
+
 def envs_from_environment_variables_map(map: Mapping[str, str]) -> List[client.V1EnvVar]:
     result = []
     for env_var, env_val in map.items():

tests/deploy/run-deploy-test.sh

@@ -6,6 +6,12 @@ fi
 # Dump environment variables for debugging
 echo "Environment variables:"
 env
+
+delete_cluster_exit () {
+    $TEST_TARGET_SO deployment --dir $test_deployment_dir stop --delete-volumes
+    exit 1
+}
+
 # Test basic stack-orchestrator deploy
 echo "Running stack-orchestrator deploy test"
 # Bit of a hack, test the most recent package
@@ -106,6 +112,10 @@ if [ ! "$create_file_content" == "create-command-output-data"  ]; then
     echo "deploy create test: FAILED"
     exit 1
 fi
+
+# Add a config file to be picked up by the ConfigMap before starting.
+echo "dbfc7a4d-44a7-416d-b5f3-29842cc47650" > $test_deployment_dir/data/test-config/test_config
+
 echo "deploy create output file test: passed"
 # Try to start the deployment
 $TEST_TARGET_SO deployment --dir $test_deployment_dir start
@@ -124,6 +134,37 @@ else
     echo "deployment config test: FAILED"
     exit 1
 fi
+# Check the config variable CERC_TEST_PARAM_2 was passed correctly from the compose file
+if [[ "$log_output_3" == *"Test-param-2: CERC_TEST_PARAM_2_VALUE"* ]]; then
+    echo "deployment compose config test: passed"
+else
+    echo "deployment compose config test: FAILED"
+    exit 1
+fi
+
+# Check that the ConfigMap is mounted and contains the expected content.
+log_output_4=$( $TEST_TARGET_SO deployment --dir $test_deployment_dir logs )
+if [[ "$log_output_4" == *"/config/test_config:"* ]] && [[ "$log_output_4" == *"dbfc7a4d-44a7-416d-b5f3-29842cc47650"* ]]; then
+    echo "deployment ConfigMap test: passed"
+else
+    echo "deployment ConfigMap test: FAILED"
+    delete_cluster_exit
+fi
+
+# Stop then start again and check the volume was preserved
+$TEST_TARGET_SO deployment --dir $test_deployment_dir stop
+# Sleep a bit just in case
+# sleep for longer to check if that's why the subsequent create cluster fails
+sleep 20
+$TEST_TARGET_SO deployment --dir $test_deployment_dir start
+log_output_5=$( $TEST_TARGET_SO deployment --dir $test_deployment_dir logs )
+if [[ "$log_output_5" == *"Filesystem is old"* ]]; then
+    echo "Retain volumes test: passed"
+else
+    echo "Retain volumes test: FAILED"
+    delete_cluster_exit
+fi
+
 # Stop and clean up
 $TEST_TARGET_SO deployment --dir $test_deployment_dir stop --delete-volumes
 echo "Test passed"

tests/k8s-deploy/run-deploy-test.sh

@@ -114,6 +114,7 @@ else
     echo "deployment logs test: FAILED"
     delete_cluster_exit
 fi
+
 # Check the config variable CERC_TEST_PARAM_1 was passed correctly
 if [[ "$log_output_3" == *"Test-param-1: PASSED"* ]]; then
     echo "deployment config test: passed"
@@ -122,6 +123,14 @@ else
     delete_cluster_exit
 fi
 
+# Check the config variable CERC_TEST_PARAM_2 was passed correctly from the compose file
+if [[ "$log_output_3" == *"Test-param-2: CERC_TEST_PARAM_2_VALUE"* ]]; then
+    echo "deployment compose config test: passed"
+else
+    echo "deployment compose config test: FAILED"
+    exit 1
+fi
+
 # Check that the ConfigMap is mounted and contains the expected content.
 log_output_4=$( $TEST_TARGET_SO deployment --dir $test_deployment_dir logs )
 if [[ "$log_output_4" == *"/config/test_config:"* ]] && [[ "$log_output_4" == *"dbfc7a4d-44a7-416d-b5f3-29842cc47650"* ]]; then