finish up the scheduler

.prettierrc

@@ -0,0 +1,18 @@
+{
+	"semi": true,
+	"singleQuote": false,
+	"trailingComma": "none",
+	"useTabs": false,
+	"printWidth": 120,
+	"endOfLine": "lf",
+	"overrides": [
+		{
+			"files": ["**/*.scss"],
+			"options": {
+				"useTabs": false,
+				"tabWidth": 2,
+				"singleQuote": true
+			}
+		}
+	]
+}

src/canary/email.ts

@@ -4,21 +4,13 @@ import * as O from "fp-ts/lib/Option";
 import { createTransport } from "nodemailer";
 import { toError } from "fp-ts/lib/Either";
 import { pipe } from "fp-ts/lib/function";
-import {
+import { ImapFlow, type FetchMessageObject, type FetchQueryObject, type MailboxLockObject } from "imapflow";
-  ImapFlow,
-  type FetchMessageObject,
-  type FetchQueryObject,
-  type MailboxLockObject,
-} from "imapflow";
 import * as IO from "fp-ts/lib/IO";
 import * as T from "fp-ts/lib/Task";
 import { ConsoleLogger } from "../util";
 
 interface ImapClientI {
-  fetchAll: (
+  fetchAll: (range: string, options: FetchQueryObject) => Promise<FetchMessageObject[]>;
-    range: string,
-    options: FetchQueryObject,
-  ) => Promise<FetchMessageObject[]>;
   connect: () => Promise<void>;
   getMailboxLock: (mailbox: string) => Promise<MailboxLockObject>;
   messageDelete: (uids: number[]) => Promise<boolean>;
@@ -40,10 +32,7 @@ class ErrorWithLock extends Error {
   }
 }
 const ToErrorWithLock = (lock?: MailboxLockObject) => (error: unknown) =>
-  new ErrorWithLock(
+  new ErrorWithLock(error instanceof Error ? error.message : "Unknown error", lock);
-    error instanceof Error ? error.message : "Unknown error",
-    lock,
-  );
 
 /**
  * Generate a unique email.
@@ -51,42 +40,31 @@ const ToErrorWithLock = (lock?: MailboxLockObject) => (error: unknown) =>
  * @param to is the email to send to.
  * @returns an {@link Email}.
  */
-type EmailGenerator = (
+type EmailGenerator = (from: EmailFromInstruction, to: EmailToInstruction) => IO.IO<Email>;
-  from: EmailFromInstruction,
+const generateEmail: EmailGenerator = (from: EmailFromInstruction, to: EmailToInstruction) => () => ({
-  to: EmailToInstruction,
+  from: from.email,
-) => IO.IO<Email>;
+  to: to.email,
-const generateEmail: EmailGenerator =
+  subject: [new Date().toISOString(), crypto.randomUUID()].join(" | "),
-  (from: EmailFromInstruction, to: EmailToInstruction) => () => ({
+  text: crypto.randomUUID()
-    from: from.email,
+});
-    to: to.email,
-    subject: [new Date().toISOString(), crypto.randomUUID()].join(" | "),
-    text: crypto.randomUUID(),
-  });
 
 /**
  * Get the transport layer for a mailbox to send a piece of mail.
  * @param param0 is the mailbox to send from.
  * @returns a function that takes an email and sends it.
  */
-type GetSendEmail = (
+type GetSendEmail = (from: EmailFromInstruction) => (email: Email) => TE.TaskEither<Error, Email>;
-  from: EmailFromInstruction,
+const getSendTransport: GetSendEmail = ({ username, password, server, send_port }) => {
-) => (email: Email) => TE.TaskEither<Error, Email>;
-const getSendTransport: GetSendEmail = ({
-  username,
-  password,
-  server,
-  send_port,
-}) => {
   const transport = createTransport({
     host: server,
     port: send_port,
     auth: {
       user: username,
-      pass: password,
+      pass: password
     },
     tls: {
-      rejectUnauthorized: false,
+      rejectUnauthorized: false
-    },
+    }
   });
   return (email: Email) =>
     TE.tryCatch(
@@ -98,9 +76,9 @@ const getSendTransport: GetSendEmail = ({
             } else {
               resolve(email);
             }
-          }),
+          })
         ),
-      toError,
+      toError
     );
 };
 
@@ -109,9 +87,7 @@ const getSendTransport: GetSendEmail = ({
  * @param param0 is the mailbox to read from.
  * @returns a Right({@link ImapFlow}) if it connected, else an Left(error).
  */
-type GetImapClient = (
+type GetImapClient = (to: EmailToInstruction) => TE.TaskEither<Error, ImapClientI>;
-  to: EmailToInstruction,
-) => TE.TaskEither<Error, ImapClientI>;
 const getImap: GetImapClient = ({ username, password, server, read_port }) => {
   const imap = new ImapFlow({
     logger: false,
@@ -120,8 +96,8 @@ const getImap: GetImapClient = ({ username, password, server, read_port }) => {
     secure: true,
     auth: {
       user: username,
-      pass: password,
+      pass: password
-    },
+    }
   });
   return TE.tryCatch(() => imap.connect().then(() => imap), toError);
 };
@@ -130,18 +106,16 @@ const getImap: GetImapClient = ({ username, password, server, read_port }) => {
  * @param imap is the Imap client to fetch messages from.
  * @returns a Right({@link FetchMessageObject}[]) if successful, else a Left(error).
  */
-const fetchMessages = (
+const fetchMessages = (imap: ImapClientI): TE.TaskEither<Error, FetchMessageObject[]> =>
-  imap: ImapClientI,
-): TE.TaskEither<Error, FetchMessageObject[]> =>
   TE.tryCatch(
     () =>
       imap.fetchAll("*", {
         uid: true,
         envelope: true,
         headers: true,
-        bodyParts: ["text"],
+        bodyParts: ["text"]
       }),
-    toError,
+    toError
   );
 
 /**
@@ -152,8 +126,7 @@ const fetchMessages = (
 type EmailMatcher = (email: Email) => (message: FetchMessageObject) => boolean;
 const matchesEmail: EmailMatcher = (email) => (message) => {
   const subjectMatches = email.subject === message.envelope.subject;
-  const bodyMatches =
+  const bodyMatches = message.bodyParts.get("text")?.toString().trim() === email.text.trim();
-    message.bodyParts.get("text")?.toString().trim() === email.text.trim();
   const headers = message.headers.toLocaleString();
   const fromMatches = headers.includes(`Return-Path: <${email.from}>`);
   const toMatches = headers.includes(`Delivered-To: ${email.to}`);
@@ -172,14 +145,9 @@ type FindEmailUidInInbox = (
   imap: ImapClientI,
   equalsEmail: (message: FetchMessageObject) => boolean,
   retries: number,
-  pollIntervalMs: number,
+  pollIntervalMs: number
 ) => TE.TaskEither<Error, number>;
-const findEmailUidInInbox: FindEmailUidInInbox = (
+const findEmailUidInInbox: FindEmailUidInInbox = (imap, equalsEmail, retries, pollIntervalMs) =>
-  imap,
-  equalsEmail,
-  retries,
-  pollIntervalMs,
-) =>
   pipe(
     fetchMessages(imap),
     TE.flatMap((messages) => {
@@ -193,17 +161,11 @@ const findEmailUidInInbox: FindEmailUidInInbox = (
       (e) =>
         pipe(
           TE.fromIO(ConsoleLogger.log(`failed; ${retries} retries left.`)),
-          TE.chain(() =>
+          TE.chain(() => (retries === 0 ? TE.left(e) : T.delay(pollIntervalMs)(TE.right(null)))),
-            retries === 0
+          TE.chain(() => findEmailUidInInbox(imap, equalsEmail, retries - 1, pollIntervalMs))
-              ? TE.left(e)
-              : T.delay(pollIntervalMs)(TE.right(null)),
-          ),
-          TE.chain(() =>
-            findEmailUidInInbox(imap, equalsEmail, retries - 1, pollIntervalMs),
-          ),
         ),
-      TE.of,
+      TE.of
-    ),
+    )
   );
 
 export type EmailJobDependencies = {
@@ -225,40 +187,31 @@ export const perform = (
     getSendImpl = getSendTransport,
     getImapImpl = getImap,
     findEmailUidInInboxImpl = findEmailUidInInbox,
-    matchesEmailImpl = matchesEmail,
+    matchesEmailImpl = matchesEmail
-  }: Partial<EmailJobDependencies> = {},
+  }: Partial<EmailJobDependencies> = {}
 ): TE.TaskEither<Error, boolean> =>
   pipe(
     // arrange.
     TE.fromIO(generateEmailImpl(from, to)),
     TE.bindTo("email"),
     // act.
-    TE.tap(({ email }) =>
+    TE.tap(({ email }) => pipe(getSendImpl(from)(email), TE.mapLeft(ToErrorWithLock()))),
-      pipe(getSendImpl(from)(email), TE.mapLeft(ToErrorWithLock())),
-    ),
     TE.bind("imap", () => pipe(getImapImpl(to), TE.mapLeft(ToErrorWithLock()))),
-    TE.bind("mailboxLock", ({ imap }) =>
+    TE.bind("mailboxLock", ({ imap }) => TE.tryCatch(() => imap.getMailboxLock("INBOX"), ToErrorWithLock())),
-      TE.tryCatch(() => imap.getMailboxLock("INBOX"), ToErrorWithLock()),
-    ),
     // "assert".
     TE.bind("uid", ({ imap, email, mailboxLock }) =>
       pipe(
-        findEmailUidInInboxImpl(
+        findEmailUidInInboxImpl(imap, matchesEmailImpl(email), retries, interval),
-          imap,
+        TE.mapLeft(ToErrorWithLock(mailboxLock))
-          matchesEmailImpl(email),
+      )
-          retries,
-          interval,
-        ),
-        TE.mapLeft(ToErrorWithLock(mailboxLock)),
-      ),
     ),
     // cleanup.
     TE.bind("deleted", ({ imap, uid, mailboxLock }) =>
       TE.tryCatch(
         //        () => imap.messageDelete([uid], { uid: true }),
         () => imap.messageDelete([uid]),
-        ToErrorWithLock(mailboxLock),
+        ToErrorWithLock(mailboxLock)
-      ),
+      )
     ),
     TE.fold(
       (e) => {
@@ -270,6 +223,6 @@ export const perform = (
       ({ mailboxLock, deleted }) => {
         mailboxLock.release();
         return TE.right(deleted);
-      },
+      }
-    ),
+    )
   );

src/canary/job.ts

@@ -38,4 +38,4 @@ export interface EmailJob {
   readRetry: Retry;
 }
 
-export type Job = EmailJob | PingJob | HealthCheckJob | DnsJob;
+export type TestJob = EmailJob | PingJob | HealthCheckJob | DnsJob;

src/canary/scheduler.ts

@@ -0,0 +1,193 @@
+import * as TE from "fp-ts/lib/TaskEither";
+import * as IO from "fp-ts/lib/IO";
+import * as RA from "fp-ts/lib/ReadonlyArray";
+import * as RM from "fp-ts/lib/ReadonlyMap";
+import * as T from "fp-ts/Task";
+import * as S from "fp-ts/string";
+import { pipe, identity } from "fp-ts/lib/function";
+import type { Separated } from "fp-ts/lib/Separated";
+import type { Magma } from "fp-ts/lib/Magma";
+import { intercalate } from "fp-ts/lib/Foldable";
+import { nextSchedule, type Schedule } from "../canary";
+import { ConsoleLogger, type Logger } from "../util";
+
+export interface Job {
+  id: string;
+  toString: () => string;
+  execute: <TResult>() => TE.TaskEither<Error, TResult>;
+  schedule: Schedule;
+  maxRetries: number;
+}
+
+export const logExecutingJobs = (jobs: ReadonlyArray<Job>, now: Date, logger: Logger = ConsoleLogger) => {
+  const stringifieds = pipe(
+    jobs,
+    RA.map(({ toString }) => toString()),
+    (stringified) => intercalate(S.Monoid, RA.Foldable)("|", stringified)
+  );
+  return logger.log(`Executing ${stringifieds} at ${now.toUTCString()}`);
+};
+
+export const execute = <TResult>(
+  jobs: ReadonlyArray<Job>
+): T.Task<Separated<ReadonlyArray<[Job, Error]>, ReadonlyArray<[Job, TResult]>>> =>
+  pipe(
+    T.of(jobs),
+    T.map(
+      RA.map((job) =>
+        pipe(
+          job.execute(),
+          TE.bimap(
+            (error) => [job, error] as [Job, Error],
+            (result) => [job, result] as [Job, TResult]
+          )
+        )
+      )
+    ),
+    T.flatMap(RA.wilt(T.ApplicativePar)(identity))
+  );
+
+export type JobsTableRow = {
+  scheduled: Date;
+  retries: number;
+};
+export type JobsTable = ReadonlyMap<string, JobsTableRow>;
+
+export const jobsTableRowMagma: Magma<JobsTableRow> = {
+  concat: (a: JobsTableRow, b: JobsTableRow): JobsTableRow => {
+    if (a.scheduled <= b.scheduled) {
+      // always prefer the later schedule.
+      return b;
+    }
+    //    if (a.retries <= b.retries) {
+    //      return a;
+    //    }
+    return b;
+  }
+};
+
+export const formatJobResults = <TResult>(
+  jobsTable: JobsTable,
+  { left, right }: Separated<ReadonlyArray<[Job, Error]>, ReadonlyArray<[Job, TResult]>>
+) => {
+  const failures = left
+    .map(([job, err]) => ({
+      job,
+      retries: jobsTable.get(job.id)?.retries ?? job.maxRetries,
+      err
+    }))
+    .filter(({ job, retries }) => retries >= job.maxRetries);
+  const retries = left
+    .map(([job, err]) => ({
+      job,
+      retries: jobsTable.get(job.id)?.retries ?? 0,
+      err
+    }))
+    .filter(({ job, retries }) => retries < job.maxRetries);
+
+  const failureMessages = failures
+    .map(({ job, err, retries }) => job.toString() + ` | ${retries} / ${job.maxRetries} |  (err) :(  | ${err.message}`)
+    .join("\n");
+  const retryMessages = retries
+    .map(
+      ({ job, err, retries }) => job.toString() + ` | ${retries} / ${job.maxRetries} |  (retry) :/  | ${err.message}`
+    )
+    .join("\n");
+  const successMessages = right.map(([job, val]) => job.toString() + " | (success) :) | " + val).join("\n");
+  return `FAILURES:\n${failureMessages}\nRETRIES:\n${retryMessages}\nSUCCESSES:\n${successMessages}`;
+};
+
+export const perform = (
+  jobsTable: JobsTable,
+  jobs: ReadonlyArray<Job>,
+  publishers: ReadonlyArray<(message: string) => TE.TaskEither<Error, number>>,
+  lastPingAck: Date,
+  publishAckEvery = 24 * (60 * 60 * 1_000),
+  logger = ConsoleLogger
+) =>
+  pipe(
+    T.of(jobs),
+    T.bindTo("jobs"),
+    T.bind(
+      "now",
+      T.fromIOK(() => IO.of(new Date()))
+    ),
+    T.bind("toExecute", ({ jobs, now }) =>
+      pipe(
+        jobs,
+        RA.filter((job) => (jobsTable.get(job.id)?.scheduled ?? now) <= now),
+        T.of
+      )
+    ),
+    T.tap(({ toExecute, now }) => T.fromIO(logExecutingJobs(toExecute, now))),
+    T.bind("results", ({ toExecute }) => execute(toExecute)),
+    T.bind("shouldAck", ({ now }) => T.of(now.getTime() - lastPingAck.getTime() >= publishAckEvery)),
+    T.tap(({ results, shouldAck }) => {
+      if (results.left.length === 0 && !shouldAck) {
+        return pipe(
+          T.of({ right: [] as ReadonlyArray<number> }),
+          T.tap(() => T.fromIO(logger.log("not publishing")))
+        );
+      }
+
+      return pipe(
+        publishers,
+        RA.map((publish) => publish(formatJobResults(jobsTable, results))),
+        RA.wilt(T.ApplicativePar)(identity),
+        T.tap(({ left }) =>
+          pipe(
+            left
+              ? logger.error("Encountered publishing errors: " + left.toString())
+              : logger.log("Published successfully"),
+            T.fromIO
+          )
+        )
+      );
+    }),
+    T.map(({ now, results: { left, right }, shouldAck }) => {
+      const result = { lastPingAck, jobsTable };
+      if (shouldAck) {
+        result.lastPingAck = now;
+      }
+
+      const leftResults = pipe(
+        left,
+        RA.map(([job]): readonly [string, JobsTableRow] => {
+          const row = jobsTable.get(job.id);
+          if (!row) {
+            return [job.id, { retries: 1, scheduled: now }];
+          }
+          if (row.retries >= job.maxRetries) {
+            logger.error(`Hit max retries; scheduling again ;-; ${job.toString()}`);
+            return [job.id, { retries: 0, scheduled: nextSchedule(job.schedule, now) }] as const;
+          }
+          return [
+            job.id,
+            {
+              retries: row.retries + 1,
+              scheduled: now
+            }
+          ] as const;
+        })
+      );
+      const results = pipe(
+        right,
+        RA.map(([job]): readonly [string, JobsTableRow] => [
+          job.id,
+          {
+            retries: 0,
+            scheduled: nextSchedule(job.schedule, now)
+          }
+        ]),
+        RA.concat(leftResults)
+      );
+
+      result.jobsTable = pipe(
+        jobsTable,
+        RM.toReadonlyArray(S.Ord),
+        RA.concat(results),
+        RM.fromFoldable(S.Eq, jobsTableRowMagma, RA.Foldable)
+      );
+      return result;
+    })
+  );

src/canary/test.ts

@@ -1,13 +1,13 @@
 import * as TE from "fp-ts/lib/TaskEither";
 import * as O from "fp-ts/lib/Option";
-import type { Job } from "./job";
+import type { TestJob } from "./job";
 import type { D } from "../util";
 
 export enum TestType {
   EMAIL = "email",
   PING = "ping",
   HEALTHCHECK = "healthcheck",
-  DNS = "dns",
+  DNS = "dns"
 }
 
 export interface Schedule {
@@ -18,13 +18,14 @@ export interface Schedule {
 export interface Test {
   name: string;
   type: TestType;
-  job: Job;
+  job: TestJob;
   schedule: Schedule;
 }
 
-export type Testable<T extends Job> = (job: T) => TE.TaskEither<Error, boolean>;
+export type Testable<TJob extends TestJob> = (job: TJob) => TE.TaskEither<Error, boolean>;
 
 export const parseTestType = (testType: string): O.Option<TestType> =>
-  Object.values(TestType).includes(testType as TestType)
+  Object.values(TestType).includes(testType as TestType) ? O.some(testType as TestType) : O.none;
-    ? O.some(testType as TestType)
+
-    : O.none;
+export const nextSchedule = (schedule: Schedule, date: Date) =>
+  new Date(date.getTime() + schedule.every + Math.random() * schedule.jitter);

src/publisher/discord.ts

@@ -0,0 +1,12 @@
+export interface DiscordPost {
+  webhook: string;
+  role_id: string;
+}
+
+export const publishDiscord = async (discordPost: DiscordPost, message: string) => {
+  console.log("Publishing to Discord");
+  return fetch(discordPost.webhook, {
+    method: "POST",
+    body: JSON.stringify({ message: `<@${discordPost.role_id}>\n${message}` })
+  }).then((r) => r.status);
+};

src/publisher/index.ts

@@ -1,23 +1,26 @@
-import { D } from "../util";
+import { toError } from "fp-ts/lib/Either";
+import * as TE from "fp-ts/TaskEither";
+import { publishDiscord, type DiscordPost } from "./discord";
+import { publishNtfy, type NtfyPost } from "./ntfy";
 
 export enum PublisherType {
   DISCORD = "discord",
-  NTFY = "ntfy",
+  NTFY = "ntfy"
 }
-
-export interface DiscordPost {
-  webhook: string;
-  role_id: string;
-}
-
-export interface NtfyPost {
-  webhook: string;
-}
-
 export type PublisherPost = DiscordPost | NtfyPost;
 
 export interface Publisher {
   type: PublisherType;
-  at: D.Duration;
   post: PublisherPost;
 }
+
+export const publish = (publisher: Publisher, message: string): TE.TaskEither<Error, number> => {
+  switch (publisher.type) {
+    case PublisherType.DISCORD:
+      return TE.tryCatch(() => publishDiscord(publisher.post as DiscordPost, message), toError);
+    case PublisherType.NTFY:
+      return TE.tryCatch(() => publishNtfy(publisher.post as NtfyPost, message), toError);
+    default:
+      return TE.left(new Error("unknown publisher type: " + publisher.type));
+  }
+};

src/publisher/ntfy.ts

@@ -0,0 +1,11 @@
+export interface NtfyPost {
+  webhook: string;
+}
+
+export const publishNtfy = async (ntfyPost: NtfyPost, message: string) => {
+  console.log("publishing to Ntfy");
+  return fetch(ntfyPost.webhook, {
+    method: "POST",
+    body: message
+  }).then((r) => r.status);
+};

src/util/duration.ts

@@ -10,7 +10,7 @@ export enum DurationUnit {
   MILLISECOND,
   SECOND,
   MINUTE,
-  HOUR,
+  HOUR
 }
 const durationUnitMap: Record<string, DurationUnit> = {
   ms: DurationUnit.MILLISECOND,
@@ -21,17 +21,14 @@ const durationUnitMap: Record<string, DurationUnit> = {
   minutes: DurationUnit.MINUTE,
   hr: DurationUnit.HOUR,
   hour: DurationUnit.HOUR,
-  hours: DurationUnit.HOUR,
+  hours: DurationUnit.HOUR
 };
-const getDurationUnit = (key: string): O.Option<DurationUnit> =>
+const getDurationUnit = (key: string): O.Option<DurationUnit> => O.fromNullable(durationUnitMap[key.toLowerCase()]);
-  O.fromNullable(durationUnitMap[key.toLowerCase()]);
 
 export const getMs = (duration: Duration): number => duration;
 export const getSeconds = (duration: Duration): number => duration / 1000;
-export const getMinutes = (duration: Duration): number =>
+export const getMinutes = (duration: Duration): number => getSeconds(duration) / 60;
-  getSeconds(duration) / 60;
+export const getHours = (duration: Duration): number => getMinutes(duration) / 60;
-export const getHours = (duration: Duration): number =>
-  getMinutes(duration) / 60;
 export const format = (duration: Duration): string => {
   const ms = getMs(duration) % 1000;
   const seconds = getSeconds(duration) % 60;
@@ -39,9 +36,7 @@ export const format = (duration: Duration): string => {
   const hours = getHours(duration);
 
   return (
-    [hours, minutes, seconds]
+    [hours, minutes, seconds].map((x) => Math.floor(x).toString().padStart(2, "0")).join(":") +
-      .map((x) => Math.floor(x).toString().padStart(2, "0"))
-      .join(":") +
     "." +
     ms.toString().padStart(3, "0")
   );
@@ -57,49 +52,40 @@ export const createDurationBuilder = (): DurationBuilder => ({
   millis: 0,
   seconds: 0,
   minutes: 0,
-  hours: 0,
+  hours: 0
 });
 
-export type DurationBuilderField<T> = (
+export type DurationBuilderField<T> = (arg: T) => (builder: DurationBuilder) => DurationBuilder;
-  arg: T,
-) => (builder: DurationBuilder) => DurationBuilder;
 
-export const withMillis: DurationBuilderField<number> =
+export const withMillis: DurationBuilderField<number> = (millis) => (builder) => ({
-  (millis) => (builder) => ({
+  ...builder,
-    ...builder,
+  millis
-    millis,
+});
-  });
 
-export const withSeconds: DurationBuilderField<number> =
+export const withSeconds: DurationBuilderField<number> = (seconds) => (builder) => ({
-  (seconds) => (builder) => ({
+  ...builder,
-    ...builder,
+  seconds
-    seconds,
+});
-  });
 
-export const withMinutes: DurationBuilderField<number> =
+export const withMinutes: DurationBuilderField<number> = (minutes) => (builder) => ({
-  (minutes) => (builder) => ({
+  ...builder,
-    ...builder,
+  minutes
-    minutes,
+});
-  });
 
-export const withHours: DurationBuilderField<number> =
+export const withHours: DurationBuilderField<number> = (hours) => (builder) => ({
-  (hours) => (builder) => ({
+  ...builder,
-    ...builder,
+  hours
-    hours,
+});
-  });
 
 export const build = (builder: DurationBuilder): Duration =>
-  builder.millis +
+  builder.millis + builder.seconds * 1000 + builder.minutes * 60 * 1000 + builder.hours * 60 * 60 * 1000;
-  builder.seconds * 1000 +
-  builder.minutes * 60 * 1000 +
-  builder.hours * 60 * 60 * 1000;
 
 export const parse = (duration: string): E.Either<string, Duration> => {
   const parts = pipe(
     duration,
     S.split(" "),
     R.map(S.trim),
-    R.filter((part) => !S.isEmpty(part)),
+    R.filter((part) => !S.isEmpty(part))
   );
 
   const valueUnitPairs = pipe(
@@ -120,36 +106,34 @@ export const parse = (duration: string): E.Either<string, Duration> => {
     E.map(
       flow(
         R.filter(O.isSome),
-        R.map(({ value }) => value),
+        R.map(({ value }) => value)
-      ),
+      )
-    ),
+    )
   );
 
   return pipe(
     valueUnitPairs,
     E.flatMap(
-      R.reduce(
+      R.reduce(E.of<string, DurationBuilder>(createDurationBuilder()), (builderEither, [unit, value]) =>
-        E.of<string, DurationBuilder>(createDurationBuilder()),
+        pipe(
-        (builderEither, [unit, value]) =>
+          builderEither,
-          pipe(
+          E.chain((builder) => {
-            builderEither,
+            switch (unit) {
-            E.chain((builder) => {
+              case DurationUnit.MILLISECOND:
-              switch (unit) {
+                return E.right(withMillis(value)(builder));
-                case DurationUnit.MILLISECOND:
+              case DurationUnit.SECOND:
-                  return E.right(withMillis(value)(builder));
+                return E.right(withSeconds(value)(builder));
-                case DurationUnit.SECOND:
+              case DurationUnit.MINUTE:
-                  return E.right(withSeconds(value)(builder));
+                return E.right(withMinutes(value)(builder));
-                case DurationUnit.MINUTE:
+              case DurationUnit.HOUR:
-                  return E.right(withMinutes(value)(builder));
+                return E.right(withHours(value)(builder));
-                case DurationUnit.HOUR:
+              default:
-                  return E.right(withHours(value)(builder));
+                return E.left(`unknown unit: ${unit}`);
-                default:
+            }
-                  return E.left(`unknown unit: ${unit}`);
+          })
-              }
+        )
-            }),
+      )
-          ),
-      ),
     ),
-    E.map(build),
+    E.map(build)
   );
 };

src/util/logger.ts

@@ -2,8 +2,10 @@ import type { IO } from "fp-ts/lib/IO";
 
 export interface Logger {
   log: (message: string) => IO<void>;
+  error: (message: string) => IO<void>;
 }
 
 export const ConsoleLogger: Logger = {
-  log: (message: string) => () => console.log(message),
+  log: (message: string) => () => console.log(new Date(), "[INFO]", message),
+  error: (message: string) => () => console.error(new Date(), "[ERROR]", message)
 };

src/util/scheduler.ts

@@ -1,25 +0,0 @@
-import * as TE from "fp-ts/lib/TaskEither";
-import { pipe } from "fp-ts/lib/function";
-import type { Schedule } from "../canary";
-
-interface ScheduledJob {
-  id: string;
-  execute: TE.TaskEither<Error, boolean>;
-  at: Date;
-  schedule: Schedule;
-}
-
-type SchedulerState = ReadonlyArray<ScheduledJob>;
-
-export const schedulerLoop =
-  (state: SchedulerState): TE.TaskEither<Error, void> =>
-  () => {
-    const loop = (currentState: SchedulerState): TE.TaskEither<Error, void> =>
-      pipe(
-        executeDueJobs(currentState),
-        delay(1000), // Delay for 1 second
-        map((newState) => loop(newState)),
-      );
-
-    return loop(state)();
-  };

tst/canary/scheduler.spec.ts

@@ -0,0 +1,197 @@
+import { mock, test, expect } from "bun:test";
+import * as TE from "fp-ts/lib/TaskEither";
+import type { Logger } from "../../src/util";
+import {
+  perform,
+  type JobsTable,
+  execute,
+  formatJobResults,
+  logExecutingJobs,
+  type Job
+} from "../../src/canary/scheduler";
+
+const getMocks = () => {
+  const mockLogger: Logger = {
+    log: mock(),
+    error: mock()
+  };
+  return { mockLogger };
+};
+
+const schedule = {
+  every: 200,
+  jitter: 100
+};
+
+test("logging", () => {
+  const { mockLogger } = getMocks();
+  const jobs: Job[] = [
+    { id: "1", toString: () => "Job 1", execute: mock(), schedule, maxRetries: 3 },
+    { id: "2", toString: () => "Job 2", execute: mock(), schedule, maxRetries: 3 }
+  ];
+  const now = new Date("2023-01-01T00:00:00Z");
+
+  logExecutingJobs(jobs, now, mockLogger);
+
+  expect(mockLogger.log).toHaveBeenCalledWith("Executing Job 1|Job 2 at Sun, 01 Jan 2023 00:00:00 GMT");
+});
+
+test("should separate jobs into successful and failed executions", async () => {
+  const job1: Job = {
+    id: "1",
+    toString: () => "Job 1",
+    execute: mock(() => TE.right("Result 1") as any),
+    schedule,
+    maxRetries: 3
+  };
+  const job2: Job = {
+    id: "2",
+    toString: () => "Job 2",
+    execute: mock(() => TE.left(new Error("Failure 2")) as any),
+    schedule,
+    maxRetries: 3
+  };
+  const jobs: Job[] = [job1, job2];
+
+  const result = await execute(jobs)();
+
+  expect(result.left).toEqual([[job2, new Error("Failure 2")]]);
+  expect(result.right).toEqual([[job1, "Result 1"]]);
+});
+
+test("should format job results correctly", () => {
+  const jobsTable: JobsTable = new Map([["1", { scheduled: new Date("2023-01-01T00:00:00Z"), retries: 1 }]]);
+  const left = [
+    [{ id: "1", toString: () => "Job 1", execute: mock(), schedule: {}, maxRetries: 3 }, new Error("Error 1")]
+  ];
+  const right = [[{ id: "2", toString: () => "Job 2", execute: mock(), schedule: {}, maxRetries: 3 }, "Success 2"]];
+
+  const result = formatJobResults(jobsTable, { left, right } as any);
+
+  expect(result).toContain("Job 1 | 1 / 3 |  (retry) :/  | Error 1");
+  expect(result).toContain("Job 2 | (success) :) | Success 2");
+});
+
+test("should update jobsTable and lastPingAck correctly", async () => {
+  const jobsTable: JobsTable = new Map([["1", { scheduled: new Date("2023-01-01T00:00:00Z"), retries: 1 }]]);
+  const jobs: Job[] = [
+    {
+      id: "1",
+      toString: () => "Job 1",
+      execute: mock(() => TE.right("Result 1") as any),
+      schedule,
+      maxRetries: 3
+    }
+  ];
+  const publishers: any = [];
+  const lastPingAck = new Date("2023-01-01T00:00:00Z");
+
+  const result = await perform(jobsTable, jobs, publishers, lastPingAck)();
+
+  expect(result.lastPingAck).not.toEqual(lastPingAck);
+  expect(result.jobsTable.get("1")).toEqual({
+    retries: 0,
+    scheduled: expect.any(Date)
+  });
+});
+
+test("should update a job with retry count on failure", async () => {
+  // Create a mock job that fails the first time but succeeds the second time
+  const job1: Job = {
+    id: "1",
+    toString: () => "Job 1",
+    execute: mock(() => TE.left(new Error("Error 1")) as any),
+    schedule,
+    maxRetries: 2
+  };
+
+  const jobsTable: JobsTable = new Map([["1", { scheduled: new Date("2023-01-01T00:00:00Z"), retries: 0 }]]);
+  const jobs: Job[] = [job1];
+  const publishers: any = [];
+  const lastPingAck = new Date("2023-01-01T00:00:00Z");
+
+  const result = await perform(jobsTable, jobs, publishers, lastPingAck, 24 * 60 * 60 * 1000)();
+
+  // Assert the job was retried once and then succeeded
+  expect(job1.execute).toHaveBeenCalled();
+
+  // Check the jobsTable for the updated state
+  expect(result.jobsTable.get("1")).toEqual({
+    retries: 1,
+    scheduled: expect.any(Date)
+  });
+});
+
+test("should reschedule a job that hits max retries", async () => {
+  // Create a mock job that fails the first time but succeeds the second time
+  const job1: Job = {
+    id: "1",
+    toString: () => "Job 1",
+    execute: mock().mockReturnValue(TE.left(new Error("Error 1"))),
+    schedule,
+    maxRetries: 4
+  };
+
+  const jobsTable: JobsTable = new Map([["1", { scheduled: new Date("2023-01-01T00:00:00Z"), retries: 4 }]]);
+  const jobs: Job[] = [job1];
+  const publishers: any = [mock().mockReturnValue(TE.right(200))];
+
+  const lastPingAck = new Date("2023-01-01T00:00:00Z");
+
+  const now = Date.now();
+  const result = await perform(jobsTable, jobs, publishers, lastPingAck, 24 * 60 * 60 * 1000)();
+  const delta = Date.now() - now;
+
+  // Assert the job was retried once and then fail
+  expect(job1.execute).toHaveBeenCalled();
+
+  // Check the jobsTable for the updated state
+  const { retries, scheduled } = result.jobsTable.get("1")!;
+  expect(retries).toEqual(0);
+  expect(publishers[0]).toHaveBeenCalled();
+
+  expect(scheduled.getTime()).toBeGreaterThan(now - delta + schedule.every);
+  expect(scheduled.getTime()).toBeLessThan(now + delta + schedule.every + schedule.jitter);
+});
+
+test("should not publish only successes when should not ack", async () => {
+  // Create a mock job that fails the first time but succeeds the second time
+  const job1: Job = {
+    id: "1",
+    toString: () => "Job 1",
+    execute: mock().mockReturnValue(TE.right(new Error("Error 1"))),
+    schedule,
+    maxRetries: 4
+  };
+
+  const jobsTable: JobsTable = new Map([["1", { scheduled: new Date("2023-01-01T00:00:00Z"), retries: 0 }]]);
+  const jobs: Job[] = [job1];
+  const publishers: any = [mock().mockReturnValue(TE.right(200))];
+  const lastPingAck = new Date();
+
+  await perform(jobsTable, jobs, publishers, lastPingAck, 24 * 60 * 60 * 1000)();
+
+  expect(job1.execute).toHaveBeenCalled();
+  expect(publishers[0]).toHaveBeenCalledTimes(0);
+});
+
+test("should publish when should ack", async () => {
+  // Create a mock job that fails the first time but succeeds the second time
+  const job1: Job = {
+    id: "1",
+    toString: () => "Job 1",
+    execute: mock().mockReturnValue(TE.right(new Error("Error 1"))),
+    schedule,
+    maxRetries: 4
+  };
+
+  const jobsTable: JobsTable = new Map([["1", { scheduled: new Date("2023-01-01T00:00:00Z"), retries: 0 }]]);
+  const jobs: Job[] = [job1];
+  const publishers: any = [mock().mockReturnValue(TE.right(200))];
+  const lastPingAck = new Date("2023-01-01T00:00:00Z");
+
+  await perform(jobsTable, jobs, publishers, lastPingAck, 24 * 60 * 60 * 1000)();
+
+  expect(job1.execute).toHaveBeenCalled();
+  expect(publishers[0]).toHaveBeenCalled();
+});