Replace configuration with a new version, identical to v2. (#295)

### What

This introduces configuration version 3, and removes versions 1 and 2.

This is most definitely a breaking change, and we're not done. Future
changes will tear this apart and rebuild it, but I wanted to make this
part easier to review.

### How

I did this in a few steps to make sure I didn't break anything.

1. I pulled out some of the lower-level configuration types to their own
files.
2. Next, I copied the remaining shared code from v1 to v2 so there were
no cross-dependencies.
3. Then I copied v2 to v3, and modified all the tests to use a v3 config
(identical to v2 except the `"version"` field).
4. Finally, I removed v1 and v2.

.github/workflows/cargo-test.yaml

@@ -126,14 +126,8 @@ jobs:
         env:
           AURORA_CONNECTION_STRING: ${{ secrets.AURORA_CONNECTION_STRING }}
         run: |
-          # take connection string from env, create NDC metadata file with it
-          cat static/aurora/v1-chinook-ndc-metadata-template.json \
-            | jq '.connectionUri={"uri":{"value":(env | .AURORA_CONNECTION_STRING)}}' \
-           > static/aurora/v1-chinook-ndc-metadata.json
-
-          cat static/aurora/v2-chinook-ndc-metadata-template.json \
-            | jq '.connectionUri={"uri":{"value":(env | .AURORA_CONNECTION_STRING)}}' \
-           > static/aurora/v2-chinook-ndc-metadata.json
+          jq '.connectionUri = {"uri": {"value": (env | .AURORA_CONNECTION_STRING)}}' static/aurora/v3-chinook-ndc-metadata-template.json \
+           > static/aurora/v3-chinook-ndc-metadata.json
 
       - name: install tools
         run: |

crates/configuration/src/configuration.rs

@@ -9,29 +9,21 @@ use ndc_sdk::connector;
 
 use query_engine_metadata::metadata;
 
-use crate::custom_trait_implementations::RawConfigurationCompat;
-use crate::version1;
-use crate::version2;
+use crate::values::{ConnectionUri, IsolationLevel, PoolSettings, ResolvedSecret};
+use crate::version3;
 
 /// Initial configuration, just enough to connect to a database and elaborate a full
 /// 'Configuration'.
-#[derive(Clone, Debug, Deserialize, Serialize)]
+#[derive(Clone, Debug, Deserialize, Serialize, JsonSchema)]
 #[serde(tag = "version")]
-#[serde(try_from = "RawConfigurationCompat")]
-#[serde(into = "RawConfigurationCompat")]
-// NOTE: Any changes to this data type will need follow-up changes to the
-// 'custom_trait_implementations' module.
 pub enum RawConfiguration {
-    // Until https://github.com/serde-rs/serde/pull/2525 is merged enum tags have to be strings.
-    #[serde(rename = "1")]
-    Version1(version1::RawConfiguration),
-    #[serde(rename = "2")]
-    Version2(version2::RawConfiguration),
+    #[serde(rename = "3")]
+    Version3(version3::RawConfiguration),
 }
 
 impl RawConfiguration {
     pub fn empty() -> Self {
-        RawConfiguration::Version2(version2::RawConfiguration::empty())
+        RawConfiguration::Version3(version3::RawConfiguration::empty())
     }
 }
 
@@ -43,26 +35,20 @@ pub struct Configuration {
 }
 
 pub async fn configure(
-    args: RawConfiguration,
+    input: RawConfiguration,
 ) -> Result<RawConfiguration, connector::UpdateConfigurationError> {
-    match args {
-        RawConfiguration::Version1(v1) => {
-            Ok(RawConfiguration::Version1(version1::configure(v1).await?))
-        }
-        RawConfiguration::Version2(v2) => {
-            Ok(RawConfiguration::Version2(version2::configure(v2).await?))
-        }
+    match input {
+        RawConfiguration::Version3(config) => Ok(RawConfiguration::Version3(
+            version3::configure(config).await?,
+        )),
     }
 }
 pub async fn validate_raw_configuration(
-    config: RawConfiguration,
+    input: RawConfiguration,
 ) -> Result<Configuration, connector::ValidateError> {
-    match config {
-        RawConfiguration::Version1(v1) => Ok(Configuration {
-            config: RawConfiguration::Version1(version1::validate_raw_configuration(v1).await?),
-        }),
-        RawConfiguration::Version2(v2) => Ok(Configuration {
-            config: RawConfiguration::Version2(version2::validate_raw_configuration(v2).await?),
+    match input {
+        RawConfiguration::Version3(config) => Ok(Configuration {
+            config: RawConfiguration::Version3(version3::validate_raw_configuration(config).await?),
         }),
     }
 }
@@ -79,47 +65,36 @@ pub async fn validate_raw_configuration(
 #[derive(Debug)]
 pub struct RuntimeConfiguration<'request> {
     pub metadata: Cow<'request, metadata::Metadata>,
-    pub pool_settings: &'request version2::PoolSettings,
+    pub pool_settings: &'request PoolSettings,
     pub connection_uri: &'request str,
-    pub isolation_level: version2::IsolationLevel,
+    pub isolation_level: IsolationLevel,
     pub mutations_version: Option<metadata::mutations::MutationsVersion>,
 }
 
 /// Apply the common interpretations on the Configuration API type into an RuntimeConfiguration.
-pub fn as_runtime_configuration(config: &Configuration) -> RuntimeConfiguration<'_> {
-    match &config.config {
-        RawConfiguration::Version1(v1) => RuntimeConfiguration {
-            metadata: Cow::Owned(version1::metadata_to_current(&v1.metadata)),
-            pool_settings: &v1.pool_settings,
-            connection_uri: match &v1.connection_uri {
-                version1::ConnectionUri::Uri(version1::ResolvedSecret(uri)) => uri,
-            },
-            isolation_level: version2::IsolationLevel::default(),
-            mutations_version: None,
-        },
-        RawConfiguration::Version2(v2) => RuntimeConfiguration {
-            metadata: Cow::Borrowed(&v2.metadata),
-            pool_settings: &v2.pool_settings,
-            connection_uri: match &v2.connection_uri {
-                version2::ConnectionUri::Uri(version2::ResolvedSecret(uri)) => uri,
+pub fn as_runtime_configuration(input: &Configuration) -> RuntimeConfiguration<'_> {
+    match &input.config {
+        RawConfiguration::Version3(config) => RuntimeConfiguration {
+            metadata: Cow::Borrowed(&config.metadata),
+            pool_settings: &config.pool_settings,
+            connection_uri: match &config.connection_uri {
+                ConnectionUri::Uri(ResolvedSecret(uri)) => uri,
             },
-            isolation_level: v2.isolation_level,
-            mutations_version: v2.configure_options.mutations_version,
+            isolation_level: config.isolation_level,
+            mutations_version: config.configure_options.mutations_version,
         },
     }
 }
 
 // for tests
 
-pub fn set_connection_uri(config: RawConfiguration, connection_uri: String) -> RawConfiguration {
-    match config {
-        RawConfiguration::Version1(v1) => RawConfiguration::Version1(version1::RawConfiguration {
-            connection_uri: version1::ConnectionUri::Uri(version1::ResolvedSecret(connection_uri)),
-            ..v1
-        }),
-        RawConfiguration::Version2(v2) => RawConfiguration::Version2(version2::RawConfiguration {
-            connection_uri: version2::ConnectionUri::Uri(version2::ResolvedSecret(connection_uri)),
-            ..v2
-        }),
+pub fn set_connection_uri(input: RawConfiguration, connection_uri: String) -> RawConfiguration {
+    match input {
+        RawConfiguration::Version3(config) => {
+            RawConfiguration::Version3(version3::RawConfiguration {
+                connection_uri: ConnectionUri::Uri(ResolvedSecret(connection_uri)),
+                ..config
+            })
+        }
     }
 }

crates/configuration/src/lib.rs

@@ -1,12 +1,11 @@
 mod configuration;
-mod custom_trait_implementations;
-pub mod version1;
-pub mod version2;
+mod values;
+
+pub mod version3;
 
 pub use configuration::{
     as_runtime_configuration, configure, set_connection_uri, validate_raw_configuration,
     Configuration, RawConfiguration, RuntimeConfiguration,
 };
-pub use version2::{
-    occurring_scalar_types, ConnectionUri, IsolationLevel, PoolSettings, ResolvedSecret,
-};
+pub use values::{ConnectionUri, IsolationLevel, PoolSettings, ResolvedSecret};
+pub use version3::occurring_scalar_types;