Merge pull request #8 from ty-ras/issue/7-add-helper-for-single-row-q…

…ueries

#7 Adding helper for single-row queries.

typed-sql/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@ty-ras-extras/typed-sql-runtypes",
-  "version": "2.0.0",
+  "version": "2.1.0",
   "author": {
     "name": "Stanislav Muhametsin",
     "email": "[email protected]",

typed-sql/src/__test__/output.spec.ts

@@ -69,3 +69,30 @@ test("Validate that validateRows invokes given validation", async (c) => {
     instanceOf: errors.SQLQueryOutputValidationError,
   });
 });
+
+test("Validate that validateOneRow invokes given validation", async (c) => {
+  c.plan(3);
+  const firstQueryResult = ["returnedRow"];
+  const secondQueryResult = ["one", "two"];
+  const thirdQueryResult = "bad-query";
+  const { usingMockedClient } = common.createMockedClientProvider([
+    firstQueryResult,
+    secondQueryResult,
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    thirdQueryResult as any,
+  ]);
+  const executor = spec.validateOneRow(
+    input.prepareSQL`SELECT 1`(usingMockedClient),
+    // Validator for single row, not many rows!
+    t.String,
+  );
+  c.deepEqual(await executor([]), "returnedRow");
+  await c.throwsAsync(async () => await executor([]), {
+    instanceOf: errors.SQLQueryOutputValidationError,
+    message: "Expected array to contain exactly one element, but contained 2.",
+  });
+  await c.throwsAsync(async () => await executor([]), {
+    instanceOf: errors.SQLQueryOutputValidationError,
+    message: "Expected string[], but was string",
+  });
+});

typed-sql/src/output.ts

@@ -6,29 +6,6 @@ import * as t from "runtypes";
 import type * as query from "./input";
 import * as errors from "./errors";
 
-/* eslint-disable @typescript-eslint/ban-types */
-
-// Unfortunately, runtypes is not capable of transforming values.
-// There is some discussion in issue https://github.com/pelotom/runtypes/issues/56
-// And PR: https://github.com/pelotom/runtypes/pull/191
-// However, this doesn't seem to be happening anytime soon, so just leave this out for now.
-// /**
-//  * Creates `runtypes` validator which ensures that input array of rows contains exactly one row with given shape.
-//  * @param singleRow The `runtypes` validator for row object.
-//  * @returns The `runtypes` validator which takes an array of rows as input, and ensures that array contains exactly one element. That element is then validated using given validator.
-//  */
-// export const one = <TValidation extends t.Runtype>(
-//   singleRow: TValidation,
-// ): t.Runtype<t.Static<TValidation>> =>
-//   many(singleRow).withConstraint<t.Static<TValidation>, void>(
-//     (array) =>
-//       // eslint-disable-next-line @typescript-eslint/no-unsafe-return
-//       array.length == 1
-//         ? array[0]
-//         : `Expected exactly 1 row, but got ${array.length}.`,
-//     { name: "SingleRow" },
-//   );
-
 /**
  * Creates `runtypes` validator which ensures that all rows of input array match given shape.
  * @param singleRow The `runtypes` validator for row object.
@@ -39,9 +16,9 @@ export const many = <TValidation extends t.Runtype>(
 ): t.Runtype<Array<t.Static<TValidation>>> => t.Array(singleRow);
 
 /**
- * Creates {@link input.SQLQueryExecutor}, which takes input from rows produced from another {@link input.SQLQueryExecutor} and validate them using the given `runtypes` validation.
+ * Creates {@link input.SQLQueryExecutor}, which takes input from rows produced from another {@link input.SQLQueryExecutor} and validates them using the given `runtypes` validation.
  * @param executor The {@link query.SQLQueryExecutor} which will provide the rows to validate.
- * @param validation The `runtypes` validation, typically obtained via {@link one} or {@link many}.
+ * @param validation The `runtypes` validation, typically obtained via {@link many}.
  * @returns The {@link input.SQLQueryExecutor}, which takes input from rows produced from another {@link input.SQLQueryExecutor} and validate them using the given `runtypes` validation.
  */
 export const validateRows = <
@@ -60,13 +37,51 @@ export const validateRows = <
     if (!maybeResult.success) {
       throw new errors.SQLQueryOutputValidationError(maybeResult);
     }
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-return
     return maybeResult.value;
   }
   retVal.sqlString = executor.sqlString;
   return retVal;
 };
 
+/**
+ * Creates {@link input.SQLQueryExecutor}, which takes input from rows produced from another {@link input.SQLQueryExecutor} and validates that only one row is present, and that the row passes the given `runtypes` validation.
+ * @param executor The {@link query.SQLQueryExecutor} which will provide the rows to validate.
+ * @param validation The `runtypes` validation for a single row.
+ * @returns The {@link input.SQLQueryExecutor}, which takes input from rows produced from another {@link input.SQLQueryExecutor} and validate them using the given `runtypes` validation.
+ */
+export const validateOneRow = <
+  TClient,
+  TParameters,
+  TValidation extends t.Runtype,
+>(
+  executor: query.SQLQueryExecutor<TClient, TParameters, Array<unknown>>,
+  validation: TValidation,
+): query.SQLQueryExecutor<TClient, TParameters, t.Static<TValidation>> => {
+  const validateRows = many(validation);
+  async function retVal(
+    client: ClientOf<typeof executor>,
+    parameters: ParametersOf<typeof executor>,
+  ) {
+    const maybeResult = validateRows.validate(
+      await executor(client, parameters),
+    );
+    if (!maybeResult.success) {
+      throw new errors.SQLQueryOutputValidationError(maybeResult);
+    }
+    const len = maybeResult.value.length;
+    if (len !== 1) {
+      throw new errors.SQLQueryOutputValidationError({
+        success: false,
+        code: "CONSTRAINT_FAILED",
+        message: `Expected array to contain exactly one element, but contained ${len}.`,
+      });
+    }
+    return maybeResult.value[0];
+  }
+  retVal.sqlString = executor.sqlString;
+  return retVal;
+};
+
 /* eslint-disable @typescript-eslint/no-explicit-any, @typescript-eslint/no-unused-vars */
 type ParametersOf<TExecutor extends query.SQLQueryExecutor<any, any, any>> =
   TExecutor extends query.SQLQueryExecutor<