The big refactor TM

6 files changed, 503 insertions, 0 deletions

diff --git a/u/trace/itrace.ts b/u/trace/itrace.ts
new file mode 100644
index 0000000..e6189d3
--- /dev/null
+++ b/u/trace/itrace.ts
@@ -0,0 +1,107 @@
+import type { Mapper, SideEffect, Supplier } from "@emprespresso/pengueno";
+
+// the "thing" every Trace writer must "trace()"
+type BaseTraceWith = string;
+export type ITraceWith<T> = BaseTraceWith | T;
+export interface ITrace<TraceWith> {
+  addTrace: Mapper<ITraceWith<TraceWith>, ITrace<TraceWith>>;
+  trace: SideEffect<ITraceWith<TraceWith>>;
+}
+
+export type ITraceableTuple<T, TraceWith> = [T, BaseTraceWith | TraceWith];
+export type ITraceableMapper<
+  T,
+  U,
+  TraceWith,
+  W = ITraceable<T, TraceWith>,
+> = (
+  w: W,
+) => U;
+
+export interface ITraceable<T, Trace = BaseTraceWith> {
+  readonly trace: ITrace<Trace>;
+  get: Supplier<T>;
+  move: <U>(u: U) => ITraceable<U, Trace>;
+  map: <U>(
+    mapper: ITraceableMapper<T, U, Trace>,
+  ) => ITraceable<U, Trace>;
+  bimap: <U>(
+    mapper: ITraceableMapper<
+      T,
+      ITraceableTuple<U, Array<Trace> | Trace>,
+      Trace
+    >,
+  ) => ITraceable<U, Trace>;
+  peek: (peek: ITraceableMapper<T, void, Trace>) => ITraceable<T, Trace>;
+  flatMap: <U>(
+    mapper: ITraceableMapper<T, ITraceable<U, Trace>, Trace>,
+  ) => ITraceable<U, Trace>;
+  flatMapAsync<U>(
+    mapper: ITraceableMapper<T, Promise<ITraceable<U, Trace>>, Trace>,
+  ): ITraceable<Promise<U>, Trace>;
+}
+
+export class TraceableImpl<T, TraceWith> implements ITraceable<T, TraceWith> {
+  protected constructor(
+    private readonly item: T,
+    public readonly trace: ITrace<TraceWith>,
+  ) {}
+
+  public map<U>(
+    mapper: ITraceableMapper<T, U, TraceWith>,
+  ) {
+    const result = mapper(this);
+    return new TraceableImpl(result, this.trace);
+  }
+
+  public flatMap<U>(
+    mapper: ITraceableMapper<
+      T,
+      ITraceable<U, TraceWith>,
+      TraceWith
+    >,
+  ): ITraceable<U, TraceWith> {
+    return mapper(this);
+  }
+
+  public flatMapAsync<U>(
+    mapper: ITraceableMapper<
+      T,
+      Promise<ITraceable<U, TraceWith>>,
+      TraceWith
+    >,
+  ): ITraceable<Promise<U>, TraceWith> {
+    return new TraceableImpl(
+      mapper(this).then((t) => t.get()),
+      this.trace,
+    );
+  }
+
+  public peek(peek: ITraceableMapper<T, void, TraceWith>) {
+    peek(this);
+    return this;
+  }
+
+  public move<Tt>(t: Tt): ITraceable<Tt, TraceWith> {
+    return this.map(() => t);
+  }
+
+  public bimap<U>(
+    mapper: ITraceableMapper<
+      T,
+      ITraceableTuple<U, Array<TraceWith> | TraceWith>,
+      TraceWith
+    >,
+  ) {
+    const [item, trace] = mapper(this);
+    const traces = Array.isArray(trace) ? trace : [trace];
+    return new TraceableImpl(
+      item,
+      traces.reduce((trace, _trace) => trace.addTrace(_trace), this.trace),
+    );
+  }
+
+  public get() {
+    return this.item;
+  }
+}
diff --git a/u/trace/logger.ts b/u/trace/logger.ts
new file mode 100644
index 0000000..a5739c8
--- /dev/null
+++ b/u/trace/logger.ts
@@ -0,0 +1,108 @@
+import {
+  isDebug,
+  type ITrace,
+  type ITraceWith,
+  type SideEffect,
+  type Supplier,
+} from "@emprespresso/pengueno";
+
+export interface ILogger {
+  log: (...args: unknown[]) => void;
+  debug: (...args: unknown[]) => void;
+  warn: (...args: unknown[]) => void;
+  error: (...args: unknown[]) => void;
+}
+export enum LogLevel {
+  UNKNOWN = "UNKNOWN",
+  INFO = "INFO",
+  WARN = "WARN",
+  DEBUG = "DEBUG",
+  ERROR = "ERROR",
+}
+const logLevelOrder: Array<LogLevel> = [
+  LogLevel.DEBUG,
+  LogLevel.INFO,
+  LogLevel.WARN,
+  LogLevel.ERROR,
+];
+export const isLogLevel = (l: string): l is LogLevel =>
+  logLevelOrder.some((level) => <string> level === l);
+
+const defaultAllowedLevels = () =>
+  [
+    LogLevel.UNKNOWN,
+    ...(isDebug() ? [LogLevel.DEBUG] : []),
+    LogLevel.INFO,
+    LogLevel.WARN,
+    LogLevel.ERROR,
+  ] as Array<LogLevel>;
+
+export const logWithLevel = (
+  logger: ILogger,
+  level: LogLevel,
+): SideEffect<unknown> => {
+  switch (level) {
+    case LogLevel.UNKNOWN:
+    case LogLevel.INFO:
+      return logger.log;
+    case LogLevel.DEBUG:
+      return logger.debug;
+    case LogLevel.WARN:
+      return logger.warn;
+    case LogLevel.ERROR:
+      return logger.error;
+  }
+};
+
+export type LogTraceSupplier = ITraceWith<Supplier<string>>;
+
+const defaultTrace = () => `[${new Date().toISOString()}]`;
+export const LoggerImpl = console;
+export class LogTrace implements ITrace<LogTraceSupplier> {
+  constructor(
+    private readonly logger: ILogger = LoggerImpl,
+    private readonly traces: Array<LogTraceSupplier> = [defaultTrace],
+    private readonly allowedLevels: Supplier<Array<LogLevel>> =
+      defaultAllowedLevels,
+    private readonly defaultLevel: LogLevel = LogLevel.INFO,
+  ) {
+  }
+
+  public addTrace(trace: LogTraceSupplier): ITrace<LogTraceSupplier> {
+    return new LogTrace(
+      this.logger,
+      this.traces.concat(trace),
+      this.allowedLevels,
+      this.defaultLevel,
+    );
+  }
+
+  public trace(trace: LogTraceSupplier) {
+    const { line, level: _level } = this.foldTraces(this.traces.concat(trace));
+    if (!this.allowedLevels().includes(_level)) return;
+
+    const level = _level === LogLevel.UNKNOWN ? this.defaultLevel : _level;
+    logWithLevel(this.logger, level)(`[${level}]${line}`);
+  }
+
+  private foldTraces(traces: Array<LogTraceSupplier>) {
+    const { line, level } = traces.reduce(
+      (acc: { line: string; level: number }, t) => {
+        const val = typeof t === "function" ? t() : t;
+        if (isLogLevel(val)) {
+          return {
+            ...acc,
+            level: Math.max(logLevelOrder.indexOf(val), acc.level),
+          };
+        }
+        const prefix = [
+          acc.line,
+          val,
+        ].join(" ");
+        return { ...acc, prefix };
+      },
+      { line: "", level: -1 },
+    );
+    return { line, level: logLevelOrder[level] ?? LogLevel.UNKNOWN };
+  }
+}
diff --git a/u/trace/metrics.ts b/u/trace/metrics.ts
new file mode 100644
index 0000000..4ddde06
--- /dev/null
+++ b/u/trace/metrics.ts
@@ -0,0 +1,143 @@
+import {
+  isObject,
+  type ITrace,
+  type ITraceWith,
+  type Mapper,
+  type SideEffect,
+  type Supplier,
+} from "@emprespresso/pengueno";
+
+export enum Unit {
+  COUNT,
+  MILLISECONDS,
+}
+
+export interface IMetric {
+  readonly count: IEmittableMetric;
+  readonly time: IEmittableMetric;
+  readonly failure: IMetric;
+  readonly success: IMetric;
+  readonly warn: IMetric;
+  readonly children: Supplier<Array<IMetric>>;
+
+  readonly _tag: "IMetric";
+}
+export const isIMetric = (t: unknown): t is IMetric =>
+  isObject(t) && "_tag" in t && t._tag === "IMetric";
+
+export interface IEmittableMetric {
+  readonly name: string;
+  readonly unit: Unit;
+  withValue: Mapper<number, MetricValue>;
+}
+
+export class EmittableMetric implements IEmittableMetric {
+  constructor(public readonly name: string, public readonly unit: Unit) {
+  }
+
+  public withValue(value: number): MetricValue {
+    return {
+      name: this.name,
+      unit: this.unit,
+      emissionTimestamp: Date.now(),
+      value,
+      _tag: "MetricValue",
+    };
+  }
+}
+
+export class Metric implements IMetric {
+  constructor(
+    public readonly count: IEmittableMetric,
+    public readonly time: IEmittableMetric,
+    public readonly failure: Metric,
+    public readonly success: Metric,
+    public readonly warn: Metric,
+    public readonly _tag: "IMetric" = "IMetric",
+  ) {}
+
+  public children() {
+    return [this.failure, this.success, this.warn];
+  }
+
+  static fromName(name: string): Metric {
+    return new Metric(
+      new EmittableMetric(`${name}.count`, Unit.COUNT),
+      new EmittableMetric(`${name}.elapsed`, Unit.MILLISECONDS),
+      Metric.fromName(`${name}.failure`),
+      Metric.fromName(`${name}.success`),
+      Metric.fromName(`${name}.warn`),
+    );
+  }
+}
+
+export interface MetricValue {
+  readonly name: string;
+  readonly unit: Unit;
+  readonly value: number;
+  readonly emissionTimestamp: number;
+  readonly _tag: "MetricValue";
+}
+export const isMetricValue = (t: unknown): t is MetricValue =>
+  isObject(t) && "_tag" in t && t._tag === "MetricValue";
+
+export const isMetricsTraceSupplier = (t: unknown): t is MetricsTraceSupplier =>
+  isMetricValue(t) || isIMetric(t);
+
+export type MetricsTraceSupplier = ITraceWith<IMetric | MetricValue>;
+type MetricTracingTuple = [IMetric, Date];
+export class MetricsTrace implements ITrace<MetricsTraceSupplier> {
+  constructor(
+    private readonly metricConsumer: SideEffect<Array<MetricValue>>,
+    private readonly tracing: Array<MetricTracingTuple> = [],
+    private readonly flushed: Set<IMetric> = new Set(),
+  ) {}
+
+  public addTrace(trace: MetricsTraceSupplier) {
+    if (isMetricValue(trace) || typeof trace === "string") return this;
+    return new MetricsTrace(this.metricConsumer)._nowTracing(trace);
+  }
+
+  public trace(metric: MetricsTraceSupplier) {
+    if (typeof metric === "string") return this;
+    if (isMetricValue(metric)) {
+      this.metricConsumer([metric]);
+      return this;
+    }
+
+    const foundMetricValues = this.tracing.flatMap((
+      [tracing, startedTracing],
+    ) =>
+      [tracing, ...tracing.children()]
+        .filter((_tracing) => metric === _tracing)
+        .flatMap((metric) => [
+          this.addMetric(metric, startedTracing),
+          this.addMetric(tracing, startedTracing),
+        ])
+    ).flatMap((values) => values);
+
+    if (foundMetricValues.length === 0) {
+      return this._nowTracing(metric);
+    }
+
+    this.metricConsumer(foundMetricValues);
+    return this;
+  }
+
+  private addMetric(metric: IMetric, startedTracing: Date): Array<MetricValue> {
+    if (this.flushed.has(metric)) {
+      return [];
+    }
+
+    this.flushed.add(metric);
+    return [
+      metric.count.withValue(1.0),
+      metric.time.withValue(Date.now() - startedTracing.getTime()),
+    ];
+  }
+
+  private _nowTracing(metric: IMetric): MetricsTrace {
+    this.tracing.push([metric, new Date()]);
+    return this;
+  }
+}
diff --git a/u/trace/mod.ts b/u/trace/mod.ts
new file mode 100644
index 0000000..0f9b61b
--- /dev/null
+++ b/u/trace/mod.ts
@@ -0,0 +1,5 @@
+export * from "./itrace.ts";
+export * from "./util.ts";
+export * from "./logger.ts";
+export * from "./metrics.ts";
+export * from "./trace.ts";
diff --git a/u/trace/trace.ts b/u/trace/trace.ts
new file mode 100644
index 0000000..e942066
--- /dev/null
+++ b/u/trace/trace.ts
@@ -0,0 +1,82 @@
+import {
+  isMetricsTraceSupplier,
+  type ITrace,
+  type ITraceWith,
+  LogTrace,
+  type LogTraceSupplier,
+  MetricsTrace,
+  type MetricsTraceSupplier,
+  type MetricValue,
+  TraceableImpl,
+} from "@emprespresso/pengueno";
+
+export class LogTraceable<T> extends TraceableImpl<T, LogTraceSupplier> {
+  public static LogTrace = new LogTrace();
+  static from<T>(t: T) {
+    return new LogTraceable(t, LogTraceable.LogTrace);
+  }
+}
+
+const getEmbeddedMetricConsumer =
+  (logTrace: LogTrace) => (metrics: Array<MetricValue>) =>
+    logTrace.addTrace("<metrics>").trace(
+      JSON.stringify(metrics, null, 2) + "</metrics>",
+    );
+export class EmbeddedMetricsTraceable<T>
+  extends TraceableImpl<T, MetricsTraceSupplier> {
+  public static MetricsTrace = new MetricsTrace(
+    getEmbeddedMetricConsumer(LogTraceable.LogTrace),
+  );
+
+  static from<T>(t: T) {
+    return new EmbeddedMetricsTraceable(
+      t,
+      EmbeddedMetricsTraceable.MetricsTrace,
+    );
+  }
+}
+
+export type LogMetricTraceSupplier = ITraceWith<
+  LogTraceSupplier | MetricsTraceSupplier
+>;
+export class LogMetricTrace implements ITrace<LogMetricTraceSupplier> {
+  constructor(
+    private logTrace: ITrace<LogTraceSupplier>,
+    private metricsTrace: ITrace<MetricsTraceSupplier>,
+  ) {}
+
+  public addTrace(
+    trace: LogTraceSupplier | MetricsTraceSupplier,
+  ): LogMetricTrace {
+    if (isMetricsTraceSupplier(trace)) {
+      this.metricsTrace = this.metricsTrace.addTrace(trace);
+      return this;
+    }
+    this.logTrace = this.logTrace.addTrace(trace);
+    return this;
+  }
+
+  public trace(trace: LogTraceSupplier | MetricsTraceSupplier) {
+    if (isMetricsTraceSupplier(trace)) {
+      this.metricsTrace.trace(trace);
+      return this;
+    }
+    this.logTrace.trace(trace);
+    return this;
+  }
+}
+
+export class LogMetricTraceable<T>
+  extends TraceableImpl<T, MetricsTraceSupplier | LogTraceSupplier> {
+  public static LogMetricTrace = new LogMetricTrace(
+    LogTraceable.LogTrace,
+    EmbeddedMetricsTraceable.MetricsTrace,
+  );
+
+  static from<T>(t: T) {
+    return new LogMetricTraceable(
+      t,
+      LogMetricTraceable.LogMetricTrace,
+    );
+  }
+}
diff --git a/u/trace/util.ts b/u/trace/util.ts
new file mode 100644
index 0000000..302c8e4
--- /dev/null
+++ b/u/trace/util.ts
@@ -0,0 +1,58 @@
+import type {
+  Callable,
+  IMetric,
+  ITraceableMapper,
+  ITraceableTuple,
+  MetricsTraceSupplier,
+} from "@emprespresso/pengueno";
+
+export class TraceUtil {
+  static withTrace<T, Trace>(
+    trace: string,
+  ): ITraceableMapper<
+    T,
+    ITraceableTuple<T, Trace | Array<Trace>>,
+    Trace
+  > {
+    return (t) => [t.get(), `[${trace}]`];
+  }
+
+  static withMetricTrace<T, Trace extends MetricsTraceSupplier>(
+    metric: IMetric,
+  ): ITraceableMapper<
+    T,
+    ITraceableTuple<T, Trace | Array<Trace>>,
+    Trace
+  > {
+    return (t) => [t.get(), metric as Trace];
+  }
+
+  static withFunctionTrace<F extends Callable, T, Trace>(
+    f: F,
+  ): ITraceableMapper<
+    T,
+    ITraceableTuple<T, Trace | Array<Trace>>,
+    Trace
+  > {
+    return TraceUtil.withTrace(f.name);
+  }
+
+  static withClassTrace<C extends object, T, Trace>(
+    c: C,
+  ): ITraceableMapper<
+    T,
+    ITraceableTuple<T, Trace | Array<Trace>>,
+    Trace
+  > {
+    return TraceUtil.withTrace(c.constructor.name);
+  }
+
+  static promiseify<T, U, Trace>(
+    mapper: ITraceableMapper<T, U, Trace>,
+  ): ITraceableMapper<Promise<T>, Promise<U>, Trace> {
+    return (traceablePromise) =>
+      traceablePromise.flatMapAsync(async (t) =>
+        t.move(await t.get()).map(mapper)
+      ).get();
+  }
+}