something is working

2022-09-15 01:55:36 -04:00
parent a0aa251c27
commit f38e69883c
1123 changed files with 251731 additions and 11 deletions
@@ -0,0 +1,271 @@
+import type { Document } from './bson';
+import { MongoInvalidArgumentError } from './error';
+import type { TagSet } from './sdam/server_description';
+import type { ClientSession } from './sessions';
+
+/** @public */
+export type ReadPreferenceLike = ReadPreference | ReadPreferenceMode;
+
+/** @public */
+export const ReadPreferenceMode = Object.freeze({
+  primary: 'primary',
+  primaryPreferred: 'primaryPreferred',
+  secondary: 'secondary',
+  secondaryPreferred: 'secondaryPreferred',
+  nearest: 'nearest'
+} as const);
+
+/** @public */
+export type ReadPreferenceMode = typeof ReadPreferenceMode[keyof typeof ReadPreferenceMode];
+
+/** @public */
+export interface HedgeOptions {
+  /** Explicitly enable or disable hedged reads. */
+  enabled?: boolean;
+}
+
+/** @public */
+export interface ReadPreferenceOptions {
+  /** Max secondary read staleness in seconds, Minimum value is 90 seconds.*/
+  maxStalenessSeconds?: number;
+  /** Server mode in which the same query is dispatched in parallel to multiple replica set members. */
+  hedge?: HedgeOptions;
+}
+
+/** @public */
+export interface ReadPreferenceLikeOptions extends ReadPreferenceOptions {
+  readPreference?:
+    | ReadPreferenceLike
+    | {
+        mode?: ReadPreferenceMode;
+        preference?: ReadPreferenceMode;
+        tags?: TagSet[];
+        maxStalenessSeconds?: number;
+      };
+}
+
+/** @public */
+export interface ReadPreferenceFromOptions extends ReadPreferenceLikeOptions {
+  session?: ClientSession;
+  readPreferenceTags?: TagSet[];
+  hedge?: HedgeOptions;
+}
+
+/**
+ * The **ReadPreference** class is a class that represents a MongoDB ReadPreference and is
+ * used to construct connections.
+ * @public
+ *
+ * @see https://docs.mongodb.com/manual/core/read-preference/
+ */
+export class ReadPreference {
+  mode: ReadPreferenceMode;
+  tags?: TagSet[];
+  hedge?: HedgeOptions;
+  maxStalenessSeconds?: number;
+  minWireVersion?: number;
+
+  public static PRIMARY = ReadPreferenceMode.primary;
+  public static PRIMARY_PREFERRED = ReadPreferenceMode.primaryPreferred;
+  public static SECONDARY = ReadPreferenceMode.secondary;
+  public static SECONDARY_PREFERRED = ReadPreferenceMode.secondaryPreferred;
+  public static NEAREST = ReadPreferenceMode.nearest;
+
+  public static primary = new ReadPreference(ReadPreferenceMode.primary);
+  public static primaryPreferred = new ReadPreference(ReadPreferenceMode.primaryPreferred);
+  public static secondary = new ReadPreference(ReadPreferenceMode.secondary);
+  public static secondaryPreferred = new ReadPreference(ReadPreferenceMode.secondaryPreferred);
+  public static nearest = new ReadPreference(ReadPreferenceMode.nearest);
+
+  /**
+   * @param mode - A string describing the read preference mode (primary|primaryPreferred|secondary|secondaryPreferred|nearest)
+   * @param tags - A tag set used to target reads to members with the specified tag(s). tagSet is not available if using read preference mode primary.
+   * @param options - Additional read preference options
+   */
+  constructor(mode: ReadPreferenceMode, tags?: TagSet[], options?: ReadPreferenceOptions) {
+    if (!ReadPreference.isValid(mode)) {
+      throw new MongoInvalidArgumentError(`Invalid read preference mode ${JSON.stringify(mode)}`);
+    }
+    if (options == null && typeof tags === 'object' && !Array.isArray(tags)) {
+      options = tags;
+      tags = undefined;
+    } else if (tags && !Array.isArray(tags)) {
+      throw new MongoInvalidArgumentError('ReadPreference tags must be an array');
+    }
+
+    this.mode = mode;
+    this.tags = tags;
+    this.hedge = options?.hedge;
+    this.maxStalenessSeconds = undefined;
+    this.minWireVersion = undefined;
+
+    options = options ?? {};
+    if (options.maxStalenessSeconds != null) {
+      if (options.maxStalenessSeconds <= 0) {
+        throw new MongoInvalidArgumentError('maxStalenessSeconds must be a positive integer');
+      }
+
+      this.maxStalenessSeconds = options.maxStalenessSeconds;
+
+      // NOTE: The minimum required wire version is 5 for this read preference. If the existing
+      //       topology has a lower value then a MongoError will be thrown during server selection.
+      this.minWireVersion = 5;
+    }
+
+    if (this.mode === ReadPreference.PRIMARY) {
+      if (this.tags && Array.isArray(this.tags) && this.tags.length > 0) {
+        throw new MongoInvalidArgumentError('Primary read preference cannot be combined with tags');
+      }
+
+      if (this.maxStalenessSeconds) {
+        throw new MongoInvalidArgumentError(
+          'Primary read preference cannot be combined with maxStalenessSeconds'
+        );
+      }
+
+      if (this.hedge) {
+        throw new MongoInvalidArgumentError(
+          'Primary read preference cannot be combined with hedge'
+        );
+      }
+    }
+  }
+
+  // Support the deprecated `preference` property introduced in the porcelain layer
+  get preference(): ReadPreferenceMode {
+    return this.mode;
+  }
+
+  static fromString(mode: string): ReadPreference {
+    return new ReadPreference(mode as ReadPreferenceMode);
+  }
+
+  /**
+   * Construct a ReadPreference given an options object.
+   *
+   * @param options - The options object from which to extract the read preference.
+   */
+  static fromOptions(options?: ReadPreferenceFromOptions): ReadPreference | undefined {
+    if (!options) return;
+    const readPreference =
+      options.readPreference ?? options.session?.transaction.options.readPreference;
+    const readPreferenceTags = options.readPreferenceTags;
+
+    if (readPreference == null) {
+      return;
+    }
+
+    if (typeof readPreference === 'string') {
+      return new ReadPreference(readPreference, readPreferenceTags, {
+        maxStalenessSeconds: options.maxStalenessSeconds,
+        hedge: options.hedge
+      });
+    } else if (!(readPreference instanceof ReadPreference) && typeof readPreference === 'object') {
+      const mode = readPreference.mode || readPreference.preference;
+      if (mode && typeof mode === 'string') {
+        return new ReadPreference(mode, readPreference.tags ?? readPreferenceTags, {
+          maxStalenessSeconds: readPreference.maxStalenessSeconds,
+          hedge: options.hedge
+        });
+      }
+    }
+
+    if (readPreferenceTags) {
+      readPreference.tags = readPreferenceTags;
+    }
+
+    return readPreference as ReadPreference;
+  }
+
+  /**
+   * Replaces options.readPreference with a ReadPreference instance
+   */
+  static translate(options: ReadPreferenceLikeOptions): ReadPreferenceLikeOptions {
+    if (options.readPreference == null) return options;
+    const r = options.readPreference;
+
+    if (typeof r === 'string') {
+      options.readPreference = new ReadPreference(r);
+    } else if (r && !(r instanceof ReadPreference) && typeof r === 'object') {
+      const mode = r.mode || r.preference;
+      if (mode && typeof mode === 'string') {
+        options.readPreference = new ReadPreference(mode, r.tags, {
+          maxStalenessSeconds: r.maxStalenessSeconds
+        });
+      }
+    } else if (!(r instanceof ReadPreference)) {
+      throw new MongoInvalidArgumentError(`Invalid read preference: ${r}`);
+    }
+
+    return options;
+  }
+
+  /**
+   * Validate if a mode is legal
+   *
+   * @param mode - The string representing the read preference mode.
+   */
+  static isValid(mode: string): boolean {
+    const VALID_MODES = new Set([
+      ReadPreference.PRIMARY,
+      ReadPreference.PRIMARY_PREFERRED,
+      ReadPreference.SECONDARY,
+      ReadPreference.SECONDARY_PREFERRED,
+      ReadPreference.NEAREST,
+      null
+    ]);
+
+    return VALID_MODES.has(mode as ReadPreferenceMode);
+  }
+
+  /**
+   * Validate if a mode is legal
+   *
+   * @param mode - The string representing the read preference mode.
+   */
+  isValid(mode?: string): boolean {
+    return ReadPreference.isValid(typeof mode === 'string' ? mode : this.mode);
+  }
+
+  /**
+   * Indicates that this readPreference needs the "secondaryOk" bit when sent over the wire
+   * @deprecated Use secondaryOk instead
+   * @see https://docs.mongodb.com/manual/reference/mongodb-wire-protocol/#op-query
+   */
+  slaveOk(): boolean {
+    return this.secondaryOk();
+  }
+
+  /**
+   * Indicates that this readPreference needs the "SecondaryOk" bit when sent over the wire
+   * @see https://docs.mongodb.com/manual/reference/mongodb-wire-protocol/#op-query
+   */
+  secondaryOk(): boolean {
+    const NEEDS_SECONDARYOK = new Set<string>([
+      ReadPreference.PRIMARY_PREFERRED,
+      ReadPreference.SECONDARY,
+      ReadPreference.SECONDARY_PREFERRED,
+      ReadPreference.NEAREST
+    ]);
+
+    return NEEDS_SECONDARYOK.has(this.mode);
+  }
+
+  /**
+   * Check if the two ReadPreferences are equivalent
+   *
+   * @param readPreference - The read preference with which to check equality
+   */
+  equals(readPreference: ReadPreference): boolean {
+    return readPreference.mode === this.mode;
+  }
+
+  /** Return JSON representation */
+  toJSON(): Document {
+    const readPreference = { mode: this.mode } as Document;
+    if (Array.isArray(this.tags)) readPreference.tags = this.tags;
+    if (this.maxStalenessSeconds) readPreference.maxStalenessSeconds = this.maxStalenessSeconds;
+    if (this.hedge) readPreference.hedge = this.hedge;
+    return readPreference;
+  }
+}