server.js

require('dotenv').config();

const config = require('./config');
const express = require('express');
const pg = require('pg');
const redis = require('redis');
const async = require('async');
const winston = require('winston');

const rclient = redis.createClient(config.redis.port, config.redis.host, {no_ready_check: config.redis.no_ready_check});

if (config.redis.password) {
    rclient.auth(config.redis.password);
}

const logger = winston.createLogger({
    level: config.logging_level,
    format: winston.format.combine(
        winston.format.timestamp(),
        winston.format.printf(info => {
            return `${info.timestamp} [${info.level}] ${info.message}`;
        })
    ),
    transports: [
        new winston.transports.Console()
    ]
});

const pool = new pg.Pool({
    connectionString: config.pg.options,
    connectionTimeoutMillis: 1000,
    max: 50
});

const app = express();

app.enable('trust proxy');
app.disable('x-powered-by');

// Set key and client if available
app.use(function(req, response, next) {
    const key = req.query.k;
    const cid = req.query.cid;

    /*
     * The full format is:
     * {
     *   client: {
     *     authed: false/true,
     *     modpacks: [id1, id2, ...]
     *   },
     *   key: {
     *     authed: false/true,
     *     key: null/string
     * }
     */
    req.access = {
        client: { authed: false },
        key: { authed: false }
    };

    async.parallel([
        function(callback) {
            getKeys(function(err, keys) {
                if (err) {
                    return callback(err, null);
                }

                if (keys.includes(key)) {
                    req.access.key = {authed: true, key: key};
                    log('info', 'Auth', 'Authenticated API key: ' + key);
                } else {
                    req.access.key.key = null;
                }
                return callback();
            });
        },
        function(callback) {
            getClients(function(err, clients) {
                if (err) {
                    return callback(err, null);
                }

                if (clients.includes(cid)) {
                    req.access.client = {authed: true, client: cid};
                    log('info', 'Auth', 'Authenticated Client ID: ' + cid);
                    getClientAccess(cid, function(err, modpacks) {
                        if (err) {
                            return callback(err, null);
                        }
                        req.access.client.modpacks = modpacks;
                        log('info', 'Auth', 'Assigned modpack access for client', modpacks);
                        return callback();
                    });
                } else {
                    req.access.client.modpacks = [];
                    return callback();
                }

            });
        },
    ], function(err) {
        if (err) {
            log('error', 'Auth', 'Error during authentication processing.', err);
        }
        next();
    });

});

app.get('/api', function(req, response) {
    return response.status(200).json({api: 'SolderJS', version: '1.0.0', stream: 'stable'}).end();
});

app.get('/api/modpack', function(req, response) {
    const options = {
        include: req.query.include
    };

    const apiResponse = {};

    getModpacks(function(err, modpacks) {
        if (err) {
            return response.status(500).json({error: 'An error has occured'});
        }

        apiResponse.modpacks = {};
        apiResponse.mirror_url = config.url.mirror;

        modpacks.forEach(function(modpack) {
            if (modpack.hidden) {
                if (req.access.key.authed) {
                    apiResponse.modpacks[modpack.slug] = modpack.name;
                }
            } else if (modpack.private) {
                if (req.access.key.authed || req.access.client.modpacks.includes(modpack.id)) {
                    apiResponse.modpacks[modpack.slug] = modpack.name;
                }
            } else {
                apiResponse.modpacks[modpack.slug] = modpack.name;
            }
        });

        if (options.include === 'full') {

            // Grab modpack builds async
            async.each(modpacks, function(modpack, callback) {
                if (apiResponse.modpacks[modpack.slug]) {
                    getModpackResponse(modpack, req, function(err, mObject) {
                        if (err) {
                            return callback(err);
                        }
                        apiResponse.modpacks[modpack.slug] = mObject;
                        callback();
                    });
                } else {
                    callback();
                }
            }, function(err) {
                if (err) {
                    return log('error', 'Database', 'Error retrieving builds for modpacks');
                }

                return response.status(200).json(apiResponse);

            });
        } else {
            return response.status(200).json(apiResponse);
        }

    });
});

app.get('/api/modpack/(:modpack)', function(req, response) {
    const slug = req.params.modpack;

    getModpack(slug, function(err, modpack) {
        if (err) {
            return response.status(500).json({error: 'An error has occured'});
        }

        if (modpack) {
            getModpackResponse(modpack, req, function(err, res) {
                return response.status(200).json(res);
            });
        } else {
            return response.status(404).json({status: 404, error: 'Modpack does not exist'});
        }

    });
});

app.get('/api/modpack/:modpack/:build', function(req, response) {
    const slug = req.params.modpack;
    const build = req.params.build;

    const options = {
        include: req.query.include
    };

    getModpack(slug, function(err, modpack) {
        if (err) {
            return response.status(500).json({error: 'An error has occured'});
        }

        if (modpack) {
            getBuild(modpack, build, function(err, build) {
                if (err) {
                    return response.status(500).json({error: 'An error has occured'});
                }

                if (build) {
                    if (build.is_published && (!build.private || ( req.access.key.authed || req.access.client.modpacks.includes(modpack.id)))) {
                        getBuildResponse(modpack, build, options, function(err, bObject) {
                            return response.status(200).json(bObject);
                        });
                    } else {
                        return response.status(403).json({status: 403, error: 'You are not authorized to view this build.'});
                    }
                } else {
                    return response.status(404).json({status: 404, error: 'Build does not exist.'});
                }
            });
        } else {
            return response.status(404).json({status: 404, error: 'Modpack does not exist'});
        }

    });
});

app.get('/api/verify/(:key)', function(req, response) {
    const key = req.params.key;

    getKey(key, function(err, key) {
        if (err) {
            return response.status(500).json({error: 'An error has occured'});
        }

        if (key) {
            return response.status(200).json({valid: 'Key Validated.', name: key.name, created_at: key.created_at});
        } else {
            return response.status(200).json({'error': 'Key does not exist'});
        }
    });
});

function getModpackResponse(modpack, req, callback) {
    const mObject = {
        name: modpack.slug,
        display_name: modpack.name,
        recommended: modpack.recommended,
        latest: modpack.latest,
        builds: []
    };

    getBuilds(modpack, function(err, builds) {
        if (err) {
            callback(err, null);
            return log('error', 'Modpack', 'Failed to get builds while building modpack response', err);
        }

        builds.forEach(function(build) {
            if (build.is_published && (!build.private || ( req.access.key.authed || req.access.client.modpacks.includes(modpack.id)))) {
                mObject.builds.push(build.version);
            }
        });

        return callback(err, mObject);
    });
}

function getBuildResponse(modpack, build, options, callback) {

    const bObject = {
        minecraft: build.minecraft,
        forge: build.forge,
        java: build.min_java,
        memory: build.min_memory || 0,
        mods: []
    };

    getMods(build, function(err, mods) {
        if (err) {
            callback(err, null);
            return log('error', 'Mods', 'Failed to get mods while building build response', err);
        }

        mods.forEach(function(mod) {
            const modObject = {
                name: mod.name,
                version: mod.version,
                md5: mod.md5,
                url: config.url.mirror + 'mods/' + mod.name + '/' + mod.name + '-' + mod.version + '.zip'
            };

            if (mod.filesize) {
                modObject['filesize'] = mod.filesize;
            }

            if (options.include === 'mods') {
                modObject['pretty_name'] = mod.pretty_name;
                modObject['author'] = mod.author;
                modObject['description'] = mod.description;
                modObject['link'] = mod.link;
            }

            bObject.mods.push(modObject);
        });

        return callback(err, bObject);
    });
}

function getKeys(callback) {
    rclient.get('api:access:keys', function(err, res) {
        if (res) {
            callback(null, JSON.parse(res));
            log('debug', 'Cache', 'Loaded keys');
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT * FROM keys';

                client.query(query, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    const keys = result.rows.map(row => row.api_key);

                    rclient.set('api:access:keys', JSON.stringify(keys));
                    rclient.expire('api:access:keys', 60);

                    callback(null, keys);
                });
            });
        }
    });
}

function getClients(callback) {
    rclient.get('api:access:clients', function(err, res) {
        if (res) {
            callback(null, JSON.parse(res));
            log('debug', 'Cache', 'Loaded clients');
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT * FROM clients';

                client.query(query, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    const clients = result.rows.map(row => row.uuid);

                    rclient.set('api:access:clients', JSON.stringify(clients));
                    rclient.expire('api:access:clients', 60);

                    callback(null, clients);
                });
            });
        }
    });
}

function getClientAccess(cid, callback) {
    pool.connect(function(err, client, done) {
        if (err) {
            callback(err, null);
            return log('error', 'Database', 'Error fetching client from pool', err);
        }

        const query = 'SELECT * FROM clients JOIN client_modpack ON clients.id = client_modpack.client_id WHERE clients.uuid=$1';
        const data = [cid];

        client.query(query, data, function(err, result) {
            done();

            if (err) {
                callback(err, null);
                return log('error', 'Database', 'Error running query', err);
            }

            const modpacks = result.rows.map(row => row.modpack_id);

            callback(null, modpacks);
        });
    });
}

function getModpacks(callback) {
    rclient.get('api:modpacks', function(err, res) {
        if (res) {
            log('debug', 'Cache', 'Loaded modpacks');
            callback(null, JSON.parse(res));
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT * FROM modpacks ORDER BY id ASC';

                client.query(query, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    if (result.rows) {
                        rclient.set('api:modpacks', JSON.stringify(result.rows));
                        rclient.expire('api:modpacks', 60 * 5);
                    }

                    callback(null, result.rows);
                });
            });
        }
    });
}

function getModpack(slug, callback) {
    rclient.get('api:modpack:' + slug, function(err, res) {
        if (res) {
            log('debug', 'Cache', 'Loaded modpack', slug);
            callback(null, JSON.parse(res));
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT * FROM modpacks WHERE slug=$1 ORDER BY id ASC LIMIT 1';
                const data = [slug];

                client.query(query, data, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    if (result.rows[0]) {
                        rclient.set('api:modpack:' + slug, JSON.stringify(result.rows[0]));
                        rclient.expire('api:modpack:' + slug, 60 * 5);
                    }

                    callback(null, result.rows[0]);
                });
            });
        }
    });
}

function getBuilds(modpack, callback) {
    rclient.get('api:modpack:builds:' + modpack.id, function(err, res) {
        if (res) {
            log('debug', 'Cache', 'Loaded builds', modpack.slug);
            callback(null, JSON.parse(res));
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT * FROM builds WHERE modpack_id=$1::int ORDER BY id ASC';
                const data = [modpack.id];

                client.query(query, data, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    if (result.rows) {
                        rclient.set('api:modpack:builds:' + modpack.id, JSON.stringify(result.rows));
                        rclient.expire('api:modpack:builds:' + modpack.id, 60 * 5);
                    }

                    callback(null, result.rows);
                });
            });
        }
    });
}

function getBuild(modpack, build, callback) {
    rclient.get('api:build:' + modpack.id + ':' + build, function(err, res) {
        if (res) {
            log('debug', 'Cache', 'Loaded build', [modpack.slug, build]);
            callback(null, JSON.parse(res));
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT * FROM builds WHERE modpack_id=$1::int AND version=$2 LIMIT 1';
                const data = [modpack.id, build];

                client.query(query, data, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    if (result.rows[0]) {
                        rclient.set('api:build:' + modpack.id + ':' + build, JSON.stringify(result.rows[0]));
                        rclient.expire('api:build:' + modpack.id + ':' + build, 60 * 5);
                    }

                    callback(null, result.rows[0]);
                });
            });
        }
    });
}

function getMods(build, callback) {
    rclient.get('api:mods:' + build.id, function(err, res) {
        if (res) {
            log('debug', 'Cache', 'Loaded mods', build.id);
            callback(null, JSON.parse(res));
        } else {
            pool.connect(function(err, client, done) {
                if (err) {
                    callback(err, null);
                    return log('error', 'Database', 'Error fetching client from pool', err);
                }

                const query = 'SELECT mods.id, * FROM build_modversion AS bmv INNER JOIN modversions AS mv ON mv.id = bmv.modversion_id INNER JOIN mods ON mods.id = mv.mod_id WHERE bmv.build_id=$1::int ORDER BY mods.name ASC';
                const data = [build.id];

                client.query(query, data, function(err, result) {
                    done();

                    if (err) {
                        callback(err, null);
                        return log('error', 'Database', 'Error running query', err);
                    }

                    if (result.rows) {
                        rclient.set('api:mods:' + build.id, JSON.stringify(result.rows));
                        rclient.expire('api:mods:' + build.id, 60 * 5);
                    }

                    callback(null, result.rows);
                });
            });
        }
    });
}

function getKey(key, callback) {
    pool.connect(function(err, client, done) {
        if (err) {
            callback(err, null);
            return log('error', 'Database', 'Error fetching client from pool', err);
        }

        const query = 'SELECT * FROM keys WHERE api_key=$1 LIMIT 1';
        const data = [key];

        client.query(query, data, function(err, result) {
            done();

            if (err) {
                callback(err, null);
                return log('error', 'Database', 'Error running query', err);
            }

            if (result.rows[0]) {
                callback(null, result.rows[0]);
            } else {
                callback(null, null);
            }
        });
    });
}

function log(level, system, msg, meta) {
    if (config.logging) {
        if (meta) {
            logger.log(level, '[API][' + system + '] ' + msg, meta);
        } else {
            logger.log(level, '[API][' + system + '] ' + msg);
        }
    }
}
app.listen(config.web.port, config.web.host, function() {
    log('info', 'Server', 'Server running on port ' + config.web.port);
});