4 files changed, 121 insertions, 0 deletions
diff --git a/src/lib/utils/index.ts b/src/lib/utils/index.ts
new file mode 100644
index 0000000..61d383d
--- /dev/null
+++ b/src/lib/utils/index.ts
@@ -0,0 +1,3 @@
+export * from './setImageUrl';
+export * from './mailer';
+export * from './retry';
diff --git a/src/lib/utils/mailer.ts b/src/lib/utils/mailer.ts
new file mode 100644
index 0000000..e5edd74
--- /dev/null
+++ b/src/lib/utils/mailer.ts
@@ -0,0 +1,61 @@
+import * as nodemailer from 'nodemailer';
+import { continueRetryUntilValidation } from './retry';
+
+export interface Mailer {
+	sendMail(to: string, subject: string, message: string): Promise<boolean>;
+}
+
+export class MistyMountainsMailer implements Mailer {
+	private from: string;
+	private domain: string;
+	private username: string;
+	private password: string;
+	private port: number;
+
+	private transporter: nodemailer.Transporter;
+
+	constructor(username: string, password: string, from: string, domain: string, port: number) {
+		this.from = from;
+		this.username = username;
+		this.password = password;
+		this.domain = domain;
+		this.port = port;
+
+		this.transporter = nodemailer.createTransport({
+			host: this.domain,
+			port: this.port,
+			auth: {
+				user: this.username,
+				pass: this.password
+			},
+			requireTLS: true,
+			tls: {
+				rejectUnauthorized: true
+			}
+		});
+	}
+
+	public async sendMail(to: string, subject: string, message: string) {
+		const mail = {
+			from: this.from,
+			subject,
+			html: message,
+			to
+		};
+
+		return !!(await continueRetryUntilValidation<string>(async () => {
+			const { messageId } = await this.transporter.sendMail(mail);
+			return messageId;
+		}));
+	}
+}
+
+export const EnvMistyMountainsMailerFactory = () => {
+	return new MistyMountainsMailer(
+		process.env.SMTP_USERNAME,
+		process.env.SMTP_PASSWORD,
+		process.env.FROM_EMAIL,
+		process.env.SMTP_SERVER,
+		Number(process.env.SMTP_PORT)
+	);
+};
diff --git a/src/lib/utils/retry.ts b/src/lib/utils/retry.ts
new file mode 100644
index 0000000..34bc73b
--- /dev/null
+++ b/src/lib/utils/retry.ts
@@ -0,0 +1,45 @@
+export type RetryStrategyF = (retries: number) => number;
+
+export const MAX_DEFAULT_RETRY_AMOUNT = 5;
+export const WAIT_MS = 1_000;
+export const RETRY_EXPONENT = 2;
+export const RETRY_EXPONENTIAL_FACTOR = 1.1;
+export const RETRY_JITTER_MAX = 3_000;
+
+const waitFor = (ms: number) => new Promise((res) => setTimeout(res, ms));
+
+const exponentialStrategyWithJitter: RetryStrategyF = (retries: number) =>
+  WAIT_MS * Math.pow(RETRY_EXPONENT, RETRY_EXPONENTIAL_FACTOR * retries) +
+  RETRY_JITTER_MAX * Math.random();
+
+export const continueRetryUntilValidation = async <T>(
+  promiseFn: () => Promise<T> | T | Promise<void> | void,
+  validationFn: (x: T) => Promise<boolean> | boolean = (x: T) =>
+    Promise.resolve(!!x),
+  maxRetries = MAX_DEFAULT_RETRY_AMOUNT,
+  waitTimeStrategy: RetryStrategyF = exponentialStrategyWithJitter,
+  retries = 0,
+  lastError: undefined | unknown = undefined
+): Promise<T> => {
+  if (retries >= maxRetries) {
+    if (lastError) throw lastError;
+    throw new Error("Exceeded maximum retry amount");
+  }
+  try {
+    if (retries) await waitFor(waitTimeStrategy(retries));
+
+    const res = await promiseFn();
+    if (res && (await validationFn(res))) return res;
+
+    throw new Error("Validation predicate unsuccessful");
+  } catch (e: unknown) {
+    return continueRetryUntilValidation(
+      promiseFn,
+      validationFn,
+      maxRetries,
+      waitTimeStrategy,
+      retries + 1,
+      e
+    );
+  }
+};
+\ No newline at end of file
diff --git a/src/lib/utils/setImageUrl.ts b/src/lib/utils/setImageUrl.ts
new file mode 100644
index 0000000..15566a8
--- /dev/null
+++ b/src/lib/utils/setImageUrl.ts
@@ -0,0 +1,12 @@
+import { supabase } from '../supabase';
+
+export const setImageUrl = (imageSpec) => {
+  const { publicURL, error } = supabase
+    .storage
+    .from('mistymountains')
+    .getPublicUrl(imageSpec.image);
+  if (!error) {
+    return { ...imageSpec, image: publicURL };
+  }
+  return imageSpec;
+}