### Install ESPN Fantasy Football API via npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This command installs the `espn-fantasy-football-api` package using npm, saving it as a dependency in your project.

```Shell
npm install --save espn-fantasy-football-api
```

--------------------------------

### Initialize ESPN Fantasy Football API Client

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

Demonstrates how to create a new instance of the `Client` class to interact with the ESPN Fantasy Football API for a specific league. This is the basic setup for public leagues.

```javascript
import { Client } from 'espn-fantasy-football-api';
const myClient = new Client({ leagueId: 432132 });
```

--------------------------------

### Run Unit Tests with Jest via npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script starts the Jest test runner to execute all unit tests. It supports `--watch` for continuous testing and allows specifying a file inclusion pattern to run specific tests.

```Shell
npm run test
```

--------------------------------

### Calculate Optimal Fantasy Football Lineup for a Week

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

A detailed example script showcasing how to use the `espn-fantasy-football-api` to determine the best possible lineup for each team in a fantasy football league for a given week. It includes logic for handling different player positions and calculating total points.

```javascript
const _ = require('lodash');
const { Client } = require('espn-fantasy-football-api/node');

const myClient = new Client({
  leagueId: 12345,
  espnS2: 'YOUR_ESPN_S2',
  SWID: 'YOUR_SWID'
});

class Psychic {
  static filterPosition(boxscorePlayer, position) {
    return (
      boxscorePlayer.position === position ||
      _.includes(boxscorePlayer.player.eligiblePositions, position)
    );
  }

  static handleNonFlexPosition(lineup, position) {
    const players = _.filter(lineup, (player) => this.filterPosition(player, position));
    const sortedPlayers = _.sortBy(players, ['totalPoints']);
    return _.last(sortedPlayers);
  }

  static analyzeLineup(lineup, score) {
    let bestSum = 0;
    const bestRoster = [];
    let numChanges = 0;

    const bestQB = this.handleNonFlexPosition(lineup, 'QB')
    bestRoster.push(bestQB.player.fullName);
    bestSum += bestQB.totalPoints;
    if (bestQB.position === 'Bench') {
      numChanges += 1;
    }

    const bestDefense = this.handleNonFlexPosition(lineup, 'D/ST')
    bestRoster.push(bestDefense.player.fullName);
    bestSum += bestDefense.totalPoints;
    if (bestDefense.position === 'Bench') {
      numChanges += 1;
    }

    const bestKicker = this.handleNonFlexPosition(lineup, 'K')
    bestRoster.push(bestKicker.player.fullName);
    bestSum += bestKicker.totalPoints;
    if (bestKicker.position === 'Bench') {
      numChanges += 1;
    }


    const flexPlayers = _.filter(lineup, (player) => this.filterPosition(player, 'RB') ||
      this.filterPosition(player, 'WR') ||
      this.filterPosition(player, 'TE')
    );
    const sortedFlexPlayers = _.sortBy(flexPlayers, ['totalPoints']);

    const flexPos = { RB: 2, WR: 2, TE: 1, FLEX: 1 };

    while (_.sum(_.values(flexPos)) && !_.isEmpty(sortedFlexPlayers)) {
      const player = sortedFlexPlayers.pop();
      const acceptPlayer = () => {
        bestRoster.push(player.player.fullName);
        bestSum += player.totalPoints;
        if (player.position === 'Bench') {
          numChanges += 1;
        }
      }

      if (flexPos.RB && _.includes(player.player.eligiblePositions, 'RB')) {
        acceptPlayer();
        flexPos.RB -= 1;
      } else if (flexPos.WR && _.includes(player.player.eligiblePositions, 'WR')) {
        acceptPlayer();
        flexPos.WR -= 1;
      } else if (flexPos.TE && _.includes(player.player.eligiblePositions, 'TE')) {
        acceptPlayer();
        flexPos.TE -= 1;
      } else if (flexPos.FLEX) {
        acceptPlayer();
        flexPos.FLEX -= 1;
      }
    }

    return {
      bestSum,
      bestRoster,
      currentScore: score,
      numChanges
    };
  }

  static runForWeek({ seasonId, matchupPeriodId, scoringPeriodId }) {
    const bestLineups = {};
    return myClient.getBoxscoreForWeek({ seasonId, matchupPeriodId, scoringPeriodId }).then((boxes) => {
      _.forEach(boxes, (box) => {
        bestLineups[box.awayTeamId] = this.analyzeLineup(box.awayRoster, box.awayScore);
        bestLineups[box.homeTeamId] = this.analyzeLineup(box.homeRoster, box.homeScore);
      });

      return bestLineups;
    });
  }
}

Psychic.runForWeek({ seasonId: 2019, matchupPeriodId: 4, scoringPeriodId: 4 }).then((result) => {
  console.log(result);
  return result;
});
```

--------------------------------

### Build and Serve Documentation with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script first builds the documentation and then serves it locally, typically on port 8080. It's useful for previewing documentation changes during development.

```Shell
npm run serve:docs
```

--------------------------------

### Build Project Documentation with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script generates the project's documentation files. It ensures that the latest documentation is available for reference.

```Shell
npm run build:docs
```

--------------------------------

### Build Project Module with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script compiles the project's source code into a distributable module. It prepares the application for deployment or packaging.

```Shell
npm run build
```

--------------------------------

### Run Integration Tests with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script specifically executes the integration tests for the project. Integration tests verify the interaction between different components of the application.

```Shell
npm run test:integration
```

--------------------------------

### Run All Lint Tasks with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script executes all defined linting tasks across the project. It helps maintain code style consistency and identify potential errors or anti-patterns.

```Shell
npm run lint
```

--------------------------------

### Run All Clean Scripts with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script executes all defined cleaning tasks within the project. It's a convenient way to remove generated files and reset the project to a clean state.

```Shell
npm run clean
```

--------------------------------

### Run Continuous Integration Tasks with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script orchestrates a series of continuous integration tasks, including linting, unit tests, integration tests, and the main build process. It's designed to ensure code quality and functionality before deployment.

```Shell
npm run ci
```

--------------------------------

### Remove Documentation Folder with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script removes the generated documentation folder. It's useful for clearing old documentation builds before generating new ones.

```Shell
npm run clean:docs
```

--------------------------------

### Remove Distribution Folder with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script specifically deletes the 'dist' folder, which typically contains compiled or bundled output. It's used to clear previous build artifacts.

```Shell
npm run clean:dist
```

--------------------------------

### Import ESPN Fantasy Football API in JavaScript

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This snippet demonstrates how to import the ESPN Fantasy Football API client in both ES6 and ES5 syntax for web and Node.js environments, including development builds.

```JavaScript
// ES6
import { ... } from 'espn-fantasy-football-api'; // web
import { ... } from 'espn-fantasy-football-api/node'; // node
import { ... } from 'espn-fantasy-football-api/web-dev'; // web development build
import { ... } from 'espn-fantasy-football-api/node-dev'; // node development build

// ES5
const { ... } = require('espn-fantasy-football-api'); // web
const { ... } = require('espn-fantasy-football-api/node'); // node
const { ... } = require('espn-fantasy-football-api/web-dev'); // web development build
const { ... } = require('espn-fantasy-football-api/node-dev'); // node development build
```

--------------------------------

### Ensure Spelling Correctness with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script performs a spelling check on project files. It helps maintain professional documentation and code comments.

```Shell
npm run lint:spelling
```

--------------------------------

### Ensure JavaScript Code Style with npm

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This script specifically checks JavaScript code for style correctness. It helps enforce coding standards and improve code readability.

```Shell
npm run lint:js
```

--------------------------------

### ESPN Fantasy Football API Conventions

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

This section defines key parameters and their meanings used across the ESPN Fantasy Football API, including `leagueId`, `seasonId`, `matchupPeriod`, and `scoringPeriod`.

```APIDOC
API Conventions:
  leagueId:
    type: integer
    description: The ID for your league.
    example: 387659
  seasonId:
    type: integer
    description: The year in which the season was played.
    example: 2018
  matchupPeriod:
    type: integer
    description: Refers to an entire match-up, including if the match-up lasts multiple weeks (not rare in playoff settings for smaller leagues).
    example: 3 (refers to the third matchup in your league)
  scoringPeriod:
    type: integer
    description: Refers to a single NFL week. Since most matchups are 1 week long, the scoringPeriod will typically match the matchupPeriod. However, for multi-week matchups, scoringPeriod allows one to get information about a specific week in the match-up (useful in multi-week playoff match-up).
    example: 3 (refers to the third week of the NFL season)
    notes:
      - A scoringPeriodId of 0 refers to the preseason before any games are played.
      - A scoringPeriodId of 18 refers to the end of the season.
    precedence: If both a matchupPeriod and a scoringPeriod are used, the scoringPeriod takes precedence.
```

--------------------------------

### Authenticate ESPN Fantasy Football Client for Private Leagues

Source: https://github.com/mkreiser/espn-fantasy-football-api/blob/main/README.md

Explains how to configure the `Client` for private leagues by providing `espn_s2` and `SWID` cookies. These cookies are obtained from browser developer tools and are essential for accessing private league data in a NodeJS environment.

```javascript
const client = new Client({
  leagueId: 12345,
  espnS2: 'YOUR_ESPN_S2',
  SWID: 'YOUR_SWID'
});

/* OR */

const myClient = new Client({ leagueId: 12345 });
myClient.setCookies({ espnS2: 'YOUR_ESPN_S2', SWID: 'YOUR_SWID' });
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.