Clean up row decoding (vapor#193)

* Based on the work in PostgresKit to improve row decoding performance, clean up the corresponding API at this layer to call through instead of half-reimplementing (incorrectly) the same logic.

* CI cleanup - update Swift versions, use generic names, don't over-test, use new checkout action

Author: gwynne

.github/workflows/test.yml

@@ -9,7 +9,6 @@ jobs:
         dbimage:
           - postgres:14
           - postgres:13
-          - postgres:12
           - postgres:11
         dbauth:
           - trust
@@ -18,69 +17,72 @@ jobs:
         swiftver:
           - swift:5.2
           - swift:5.5
+          - swift:5.6
           - swiftlang/swift:nightly-main
         swiftos:
           - focal
+        include:
+          - swiftver: swift:5.2
+            test_flag: --enable-test-discovery
     container: ${{ format('{0}-{1}', matrix.swiftver, matrix.swiftos) }}
     runs-on: ubuntu-latest
     env:
       LOG_LEVEL: debug
-      POSTGRES_DB_A: 'vapor_database'
-      POSTGRES_DB_B: 'vapor_database'
-      POSTGRES_USER_A: 'vapor_username'
-      POSTGRES_USER_B: 'vapor_username'
-      POSTGRES_PASSWORD_A: 'vapor_password'
-      POSTGRES_PASSWORD_B: 'vapor_password'
+      POSTGRES_DB_A: 'test_database'
+      POSTGRES_DB_B: 'test_database'
+      POSTGRES_USER_A: 'test_username'
+      POSTGRES_USER_B: 'test_username'
+      POSTGRES_PASSWORD_A: 'test_password'
+      POSTGRES_PASSWORD_B: 'test_password'
       POSTGRES_HOSTNAME_A: 'psql-a'
       POSTGRES_HOSTNAME_B: 'psql-b'
       POSTGRES_HOST_AUTH_METHOD: ${{ matrix.dbauth }}
     services:
       psql-a:
         image: ${{ matrix.dbimage }}
         env:
-          POSTGRES_USER: 'vapor_username'
-          POSTGRES_DB: 'vapor_database'
-          POSTGRES_PASSWORD: 'vapor_password'
+          POSTGRES_USER: 'test_username'
+          POSTGRES_DB: 'test_database'
+          POSTGRES_PASSWORD: 'test_password'
           POSTGRES_HOST_AUTH_METHOD: ${{ matrix.dbauth }}
           POSTGRES_INITDB_ARGS: --auth-host=${{ matrix.dbauth }}
       psql-b:
         image: ${{ matrix.dbimage }}
         env:
-          POSTGRES_USER: 'vapor_username'
-          POSTGRES_DB: 'vapor_database'
-          POSTGRES_PASSWORD: 'vapor_password'
+          POSTGRES_USER: 'test_username'
+          POSTGRES_DB: 'test_database'
+          POSTGRES_PASSWORD: 'test_password'
           POSTGRES_HOST_AUTH_METHOD: ${{ matrix.dbauth }}
           POSTGRES_INITDB_ARGS: --auth-host=${{ matrix.dbauth }}
     steps:
       - name: Check out package
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Run all tests with Thread Sanitizer
-        run: swift test --enable-test-discovery --sanitize=thread
+        run: swift test ${{ matrix.test_flag }} --sanitize=thread
 
   macos-all:
     strategy:
       fail-fast: false
       matrix:
+        # Only test latest version and one auth method on macOS
         dbimage:
-          # Only test the lastest version on macOS, let Linux do the rest
           - postgresql@14
         dbauth:
-          # Only test one auth method on macOS, Linux tests will cover the others
           - scram-sha-256
         xcode:
           - latest-stable
-          - latest
+          #- latest
     runs-on: macos-11
     env:
       LOG_LEVEL: debug
       POSTGRES_HOSTNAME_A: 127.0.0.1
       POSTGRES_HOSTNAME_B: 127.0.0.1
-      POSTGRES_USER_A: 'vapor_username'
-      POSTGRES_USER_B: 'vapor_username'
-      POSTGRES_PASSWORD_A: 'vapor_password'
-      POSTGRES_PASSWORD_B: 'vapor_password'
-      POSTGRES_DB_A: 'vapor_database_a'
-      POSTGRES_DB_B: 'vapor_database_b'
+      POSTGRES_USER_A: 'test_username'
+      POSTGRES_USER_B: 'test_username'
+      POSTGRES_PASSWORD_A: 'test_password'
+      POSTGRES_PASSWORD_B: 'test_password'
+      POSTGRES_DB_A: 'test_database_a'
+      POSTGRES_DB_B: 'test_database_b'
     steps:
       - name: Select latest available Xcode
         uses: maxim-lobanov/setup-xcode@v1
@@ -100,7 +102,7 @@ jobs:
           psql $POSTGRES_DB_B <<<"ALTER SCHEMA public OWNER TO $POSTGRES_USER_B;"
         timeout-minutes: 2
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Run all tests with Thread Sanitizer
         run: |
           swift test --sanitize=thread -Xlinker -rpath \

Sources/FluentPostgresDriver/PostgresRow+Database.swift

@@ -1,5 +1,3 @@
-import class Foundation.JSONDecoder
-
 extension PostgresRow {
     internal func databaseOutput(using decoder: PostgresDataDecoder) -> DatabaseOutput {
         _PostgresDatabaseOutput(
@@ -10,40 +8,33 @@ extension PostgresRow {
 }
 
 private struct _PostgresDatabaseOutput: DatabaseOutput {
-    let row: PostgresRow
-    let decoder: PostgresDataDecoder
-
+    let row: SQLRow
+    
+    init(row: PostgresRow, decoder: PostgresDataDecoder) {
+        self.row = row.sql(decoder: decoder)
+    }
+    
     var description: String {
-        self.row.description
+        String(describing: self.row)
     }
 
-    func decodeNil(_ key: FieldKey) throws -> Bool {
-        if let data = self.row.column(self.columnName(key)) {
-            return data.type == .null
-        } else {
-            return true
-        }
+    func schema(_ schema: String) -> DatabaseOutput {
+        _SchemaDatabaseOutput(output: self, schema: schema)
     }
 
     func contains(_ key: FieldKey) -> Bool {
-        self.row.column(self.columnName(key)) != nil
+        self.row.contains(column: self.columnName(key))
     }
 
-    func schema(_ schema: String) -> DatabaseOutput {
-        _SchemaDatabaseOutput(
-            output: self,
-            schema: schema
-        )
+    func decodeNil(_ key: FieldKey) throws -> Bool {
+        try self.row.decodeNil(column: self.columnName(key))
     }
 
-    func decode<T>(_ key: FieldKey, as type: T.Type) throws -> T
-        where T: Decodable
-    {
-        try self.row.sql(decoder: self.decoder)
-            .decode(column: self.columnName(key), as: T.self)
+    func decode<T>(_ key: FieldKey, as type: T.Type) throws -> T where T: Decodable {
+        try self.row.decode(column: self.columnName(key), as: T.self)
     }
 
-    func columnName(_ key: FieldKey) -> String {
+    private func columnName(_ key: FieldKey) -> String {
         switch key {
         case .id:
             return "id"