Add migration for changed containerd config template path

RELEASE.toml

@@ -1,7 +1,7 @@
-version = "0.2.0"
-datastore_version = "0.1"
+version = "0.2.1"
+datastore_version = "0.2"
 
 [[migrations]]
-from = "0.1.6"
-to = "0.2.0"
-names = ["migrate_0.1_borkseed", "migrate_0.1_host-containers-version-migration"]
+from = "0.2.0"
+to = "0.2.1"
+names = ["migrate_0.2_containerd-config-path"]

packages/workspaces/data-store-version

@@ -1 +1 @@
-0.1
+0.2

workspaces/Cargo.toml

@@ -20,6 +20,7 @@ members = [
     # workspace member when we add cross-workspace dependencies.
     "api/migration/migrations/v0.1/borkseed",
     "api/migration/migrations/v0.1/host-containers-version",
+    "api/migration/migrations/v0.2/containerd-config-path",
 
     "models",
 

workspaces/api/migration/migrations/v0.2/containerd-config-path/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "containerd-config-path"
+version = "0.1.0"
+authors = ["Tom Kirchner <[email protected]>"]
+edition = "2018"
+publish = false
+
+[dependencies]
+migration-helpers = { path = "../../../migration-helpers" }
+serde_json = "1.0"
+snafu = "0.6"

workspaces/api/migration/migrations/v0.2/containerd-config-path/src/main.rs

@@ -0,0 +1,49 @@
+#![deny(rust_2018_idioms)]
+
+use migration_helpers::{migrate, Migration, MigrationData, Result};
+use std::process;
+
+/// We changed the path to our containerd configuration template so that we could support image
+/// variants with different configs.  We need to update old images to the new path, and on
+/// downgrade, new images to the old path.
+struct ContainerdConfigPath;
+
+const SETTING: &str = "configuration-files.containerd-config-toml.template-path";
+// Old version with no variant
+const DEFAULT_CTRD_CONFIG_OLD: &str = "/usr/share/templates/containerd-config-toml";
+// Any users coming from old versions would be using the aws-k8s variant because no other existed :)
+const DEFAULT_CTRD_CONFIG_NEW: &str = "/usr/share/templates/containerd-config-toml_aws-k8s";
+
+impl Migration for ContainerdConfigPath {
+    fn forward(&mut self, mut input: MigrationData) -> Result<MigrationData> {
+        if let Some(cfg_path) = input.data.get_mut(SETTING) {
+            if cfg_path.as_str() == Some(DEFAULT_CTRD_CONFIG_OLD) {
+                *cfg_path = serde_json::Value::String(DEFAULT_CTRD_CONFIG_NEW.to_string());
+            }
+        }
+        Ok(input)
+    }
+
+    fn backward(&mut self, mut input: MigrationData) -> Result<MigrationData> {
+        if let Some(cfg_path) = input.data.get_mut(SETTING) {
+            if cfg_path.as_str() == Some(DEFAULT_CTRD_CONFIG_NEW) {
+                *cfg_path = serde_json::Value::String(DEFAULT_CTRD_CONFIG_OLD.to_string());
+            }
+        }
+        Ok(input)
+    }
+}
+
+fn run() -> Result<()> {
+    migrate(ContainerdConfigPath)
+}
+
+// Returning a Result from main makes it print a Debug representation of the error, but with Snafu
+// we have nice Display representations of the error, so we wrap "main" (run) and print any error.
+// https://github.com/shepmaster/snafu/issues/110
+fn main() {
+    if let Err(e) = run() {
+        eprintln!("{}", e);
+        process::exit(1);
+    }
+}

workspaces/deny.toml

@@ -32,6 +32,7 @@ skip = [
     { name = "block-party", licenses = [] },
     { name = "bork", licenses = [] },
     { name = "borkseed-migration", licenses = [] },
+    { name = "containerd-config-path", licenses = [] },
     { name = "data_store_version", licenses = [] },
     { name = "growpart", licenses = [] },
     { name = "host-containers", licenses = [] },