DCD-686: Rename role to reflect updated functionality and exand restore functionality.

roles/restore_backups/tasks/amazon.yml

@@ -0,0 +1,7 @@
+---
+
+# Amazon Linux 2 supplies extra packages via a special command.
+- name: Enable Postgresql from 'extras'
+  command: amazon-linux-extras install -y "postgresql{{ postgres_version }}"
+  args:
+    creates: /usr/bin/psql

roles/restore_backups/tasks/main.yml

@@ -0,0 +1,136 @@
+---
+
+# This role will attempt to fetch and load the backup manifest from a
+# remote HTTP or S3 URL. On successful completion the contents of JSON
+# or YAML document will be in the var `atl_backup_manifest`.
+#
+# PREREQUISITES:
+#  * `atl_backup_manifest_url` points at the manifest.
+#  * The shared home filesystem is mounted if necessary (e.g. NFS/EFS).
+#  * The database has been created and the variable `db_created` is
+#    registered with the result (i.e: `register: db_created`).
+#
+# NOTE: The actual DB/FS restore operations could potentially be split
+# out into discrete roles, but currently that is not required.
+
+- block:
+
+    - name: Ensure temp directory is present
+      file:
+        path: "{{ atl_installer_temp }}"
+        state: directory
+        mode: 0750
+        owner: "{{ atl_product_user }}"
+        group: "{{ atl_product_user }}"
+      changed_when: false  # For Molecule idempotence check
+
+    - name: Parse the manifest URL
+      set_fact:
+        atl_backup_manifest_url: "{{ atl_backup_manifest_url | urlsplit }}"
+
+    - name: Extract manifest file information
+      set_fact:
+        atl_backup_manifest_bucket: "{{ atl_backup_manifest_url.hostname }}"
+        atl_backup_manifest_path: "{{ atl_backup_manifest_url.path }}"
+        atl_backup_manifest_dest: "{{ atl_installer_temp }}/{{ atl_backup_manifest_url.path | basename }}"
+
+    - name: Fetch the manifest from S3
+      aws_s3:
+        mode: get
+        overwrite: different
+        bucket: "{{ atl_backup_manifest_bucket }}"
+        object: "{{ atl_backup_manifest_path }}"
+        dest: "{{ atl_backup_manifest_dest }}"
+      when: atl_backup_manifest_url.scheme == 's3'
+
+    - name: Fetch the manifest from remote host
+      get_url:
+        url: "{{ atl_backup_manifest_url }}"
+        dest: "{{ atl_backup_manifest_dest }}"
+      when: atl_backup_manifest_url.scheme != 's3'
+
+    - name: Load parameters from manifest
+      include_vars:
+        file: "{{ atl_backup_manifest_dest }}"
+        name: atl_backup_manifest
+
+    - name: Define the DB and home dump destinations
+      set_fact:
+        # FIXME: The manifest format is still undecided so the
+        # following usages will need to be updated once it settles..
+        atl_backup_id: "{{ atl_backup_manifest.name }}"
+        atl_backup_db_dest: "{{ atl_installer_temp }}/{{ atl_backup_manifest.db_dump | basename }}"
+        atl_backup_home_dest: "{{ atl_installer_temp }}/{{ atl_backup_manifest.shared_home_dump | basename }}"
+
+    # FIXME: Here we fetch the backups. However we may wish to stream
+    # these directly from S3 to the target DB/FS to avoid requiring
+    # disk-space for the intermediate files.
+    - name: Fetch DB backup from S3
+      aws_s3:
+        mode: get
+        overwrite: different
+        bucket: "{{ atl_backup_manifest.db_dump | urlsplit('hostname') }}"
+        object: "{{ atl_backup_manifest.db_dump | urlsplit('path') }}"
+        dest: "{{ atl_backup_db_dest }}"
+
+    - name: Fetch Home backup from S3
+      aws_s3:
+        mode: get
+        overwrite: different
+        bucket: "{{ atl_backup_manifest.shared_home_dump | urlsplit('hostname') }}"
+        object: "{{ atl_backup_manifest.shared_home_dump | urlsplit('path') }}"
+        dest: "{{ atl_backup_home_dest }}"
+
+    - name: Install distro-specific restore support packages
+      include_tasks: "{{ ansible_distribution|lower }}.yml"
+
+
+    - name: Restore application database
+      postgresql_db:
+        login_host: "{{ atl_db_host }}"
+        login_user: "{{ atl_db_root_user }}"
+        login_password: "{{ atl_db_root_password }}"
+        port: "{{ atl_db_port }}"
+        name: "{{ atl_jdbc_db_name }}"
+        owner: "{{ atl_jdbc_user }}"
+        encoding: "{{ atl_jdbc_encoding }}"
+        lc_collate: "{{ atl_jdbc_collation }}"
+        lc_ctype: "{{ atl_jdbc_ctype }}"
+        template: "{{ atl_jdbc_template }}"
+        # Depends on fetch_backup roles
+        state: restore
+        target: "{{ atl_backup_db_dest }}"
+      when: db_created.changed and atl_backup_db_dest is defined
+
+
+    - name: Check for the restore canary file
+      stat:
+        path: "{{ atl_backup_home_restore_canary_path }}"
+      register: restore_canary
+
+    - block:
+
+        - name: Create shared home if necessary
+          file:
+            path: "{{ atl_product_home_shared }}"
+            state: directory
+            mode: 0750
+            owner: "{{ atl_product_user }}"
+            group: "{{ atl_product_user }}"
+
+        - name: Restore the shared-home backup
+          unarchive:
+            path: "{{ atl_backup_home_restore_canary_path }}"
+            dest: "{{ atl_product_home_shared }}"
+            owner: "{{ atl_product_user }}"
+            group: "{{ atl_product_user }}"
+
+        - name: Create restore-canary if necessary
+          copy:
+            dest: "{{ atl_backup_home_restore_canary_path }}"
+            content: "{{ atl_backup_id }}"
+
+      when: not restore_canary.stat.exists
+
+
+  when: atl_backup_manifest_url is defined and atl_backup_manifest_url != ''