chore: added existing utils from old backend repo

2022-12-07 23:14:49 +05:30
parent ef95a8a305
commit d4c775a537
1 changed files with 112 additions and 0 deletions
--- a/packages/hoppscotch-backend/src/utils.ts
+++ b/packages/hoppscotch-backend/src/utils.ts
@@ -0,0 +1,112 @@
+import { ExecutionContext } from '@nestjs/common';
+import { GqlExecutionContext } from '@nestjs/graphql';
+import { pipe } from 'fp-ts/lib/function';
+import * as O from 'fp-ts/Option';
+import * as TE from 'fp-ts/TaskEither';
+import * as T from 'fp-ts/Task';
+import { User } from './user/user.model';
+import * as A from 'fp-ts/Array';
+// import { Reflector } from '@nestjs/core';
+// import { TeamMemberRole } from './team/team.model';
+
+/**
+ * A workaround to throw an exception in an expression.
+ * JS throw keyword creates a statement not an expression.
+ * This function allows throw to be used as an expression
+ * @param errMessage Message present in the error message
+ */
+export function throwErr(errMessage: string): never {
+  throw new Error(errMessage);
+}
+
+/**
+ * Prints the given value to log and returns the same value.
+ * Used for debugging functional pipelines.
+ * @param val The value to print
+ * @returns `val` itself
+ */
+export const trace = <T>(val: T) => {
+  console.log(val);
+  return val;
+};
+
+/**
+ * Similar to `trace` but allows for labels and also an
+ * optional transform function.
+ * @param name The label to given to the trace log (log outputs like this "<name>: <value>")
+ * @param transform An optional function to transform the log output value (useful for checking specific aspects or transforms (duh))
+ * @returns A function which takes a value, and is traced.
+ */
+export const namedTrace =
+  <T>(name: string, transform?: (val: T) => unknown) =>
+  (val: T) => {
+    console.log(`${name}:`, transform ? transform(val) : val);
+
+    return val;
+  };
+
+/**
+ * Returns the list of required roles annotated on a GQL Operation
+ * @param reflector NestJS Reflector instance
+ * @param context NestJS Execution Context
+ * @returns An Option which contains the defined roles
+ */
+// export const getAnnotatedRequiredRoles = (
+//   reflector: Reflector,
+//   context: ExecutionContext,
+// ) =>
+//   pipe(
+//     reflector.get<TeamMemberRole[]>('requiresTeamRole', context.getHandler()),
+//     O.fromNullable,
+//   );
+
+/**
+ * Gets the user from the NestJS GQL Execution Context.
+ * Usually used within guards.
+ * @param ctx The Execution Context to use to get it
+ * @returns An Option of the user
+ */
+export const getUserFromGQLContext = (ctx: ExecutionContext) =>
+  pipe(
+    ctx,
+    GqlExecutionContext.create,
+    (ctx) => ctx.getContext<{ user?: User }>(),
+    ({ user }) => user,
+    O.fromNullable,
+  );
+
+/**
+ * Gets a GQL Argument in the defined operation.
+ * Usually used in guards.
+ * @param argName The name of the argument to get
+ * @param ctx The NestJS Execution Context to use to get it.
+ * @returns The argument value typed as `unknown`
+ */
+export const getGqlArg = <ArgName extends string>(
+  argName: ArgName,
+  ctx: ExecutionContext,
+) =>
+  pipe(
+    ctx,
+    GqlExecutionContext.create,
+    (ctx) => ctx.getArgs<object>(),
+    // We are not sure if this thing will even exist
+    // We pass that worry to the caller
+    (args) => args[argName as any] as unknown,
+  );
+
+/**
+ * Sequences an array of TaskEither values while maintaining an array of all the error values
+ * @param arr Array of TaskEithers
+ * @returns A TaskEither saying all the errors possible on the left or all the success values on the right
+ */
+export const taskEitherValidateArraySeq = <A, B>(
+  arr: TE.TaskEither<A, B>[],
+): TE.TaskEither<A[], B[]> =>
+  pipe(
+    arr,
+    A.map(TE.mapLeft(A.of)),
+    A.sequence(
+      TE.getApplicativeTaskValidation(T.ApplicativeSeq, A.getMonoid<A>()),
+    ),
+  );