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Diffstat (limited to '')
| -rw-r--r-- | lib/db.js | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/lib/db.js b/lib/db.js new file mode 100644 index 00000000..d763eb83 --- /dev/null +++ b/lib/db.js @@ -0,0 +1,146 @@ +//db +//external modules +var pg = require('pg'); +var fs = require('fs'); +var util = require('util'); + +//core +var config = require("../config.js"); + +//public +var db = { + readFromFile: readFromDB, + saveToFile: saveToFile, + newToDB: newToDB, + readFromDB: readFromDB, + saveToDB: saveToDB, + countFromDB: countFromDB +}; + +function getDBClient() { + if (config.debug) + return new pg.Client(config.postgresqlstring); + else + return new pg.Client(process.env.DATABASE_URL); +} + +function readFromFile(callback) { + fs.readFile('hackmd', 'utf8', function (err, data) { + if (err) throw err; + callback(data); + }); +} + +function saveToFile(doc) { + fs.writeFile('hackmd', doc, function (err) { + if (err) throw err; + }); +} + +var updatequery = "UPDATE notes SET title='%s', content='%s', update_time=NOW() WHERE id='%s';"; +var insertquery = "INSERT INTO notes (id, owner, content) VALUES ('%s', '%s', '%s');"; +var insertifnotexistquery = "INSERT INTO notes (id, owner, content) \ +SELECT '%s', '%s', '%s' \ +WHERE NOT EXISTS (SELECT 1 FROM notes WHERE id='%s') RETURNING *;"; +var selectquery = "SELECT * FROM notes WHERE id='%s';"; +var countquery = "SELECT count(*) FROM notes;"; + +function newToDB(id, owner, body, callback) { + var client = getDBClient(); + client.connect(function (err) { + if (err) { + callback(err, null); + return console.error('could not connect to postgres', err); + } + var newnotequery = util.format(insertquery, id, owner, body); + //console.log(newnotequery); + client.query(newnotequery, function (err, result) { + if (err) { + callback(err, null); + return console.error("new note to db failed: " + err); + } else { + if (config.debug) + console.log("new note to db success"); + callback(null, result); + client.end(); + } + }); + }); +} + +function readFromDB(id, callback) { + var client = getDBClient(); + client.connect(function (err) { + if (err) { + callback(err, null); + return console.error('could not connect to postgres', err); + } + var readquery = util.format(selectquery, id); + //console.log(readquery); + client.query(readquery, function (err, result) { + if (err) { + callback(err, null); + return console.error("read from db failed: " + err); + } else { + //console.log(result.rows); + if (result.rows.length <= 0) { + callback("not found note in db", null); + } else { + console.log("read from db success"); + callback(null, result); + client.end(); + } + } + }); + }); +} + +function saveToDB(id, title, data, callback) { + var client = getDBClient(); + client.connect(function (err) { + if (err) { + callback(err, null); + return console.error('could not connect to postgres', err); + } + var savequery = util.format(updatequery, title, data, id); + //console.log(savequery); + client.query(savequery, function (err, result) { + if (err) { + callback(err, null); + return console.error("save to db failed: " + err); + } else { + if (config.debug) + console.log("save to db success"); + callback(null, result); + client.end(); + } + }); + }); +} + +function countFromDB(callback) { + var client = getDBClient(); + client.connect(function (err) { + if (err) { + callback(err, null); + return console.error('could not connect to postgres', err); + } + client.query(countquery, function (err, result) { + if (err) { + callback(err, null); + return console.error("count from db failed: " + err); + } else { + //console.log(result.rows); + if (result.rows.length <= 0) { + callback("not found note in db", null); + } else { + console.log("count from db success"); + callback(null, result); + client.end(); + } + } + }); + }); +} + +module.exports = db;
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