20 Commits

Author SHA1 Message Date
Brian M. Carlson
1822f399d2 Bump version 2014-04-06 11:09:28 -05:00
Brian C
208861d057 Merge pull request #11 from drob/add-test
Adds a smoke test for copying with BINARY.
2014-04-06 11:06:16 -05:00
Brian C
1957554301 Merge pull request #10 from drob/handler-leak
Fixes another event handler leak.
2014-04-06 11:06:09 -05:00
Dan Robinson
bef3ba5fcd Adds a smoke test for copying with BINARY. 2014-04-06 04:50:54 -07:00
Dan Robinson
591a11c955 Fixes another event handler leak.
It turns out 'error' handlers were leaking as well, although more slowly.
2014-04-06 03:49:25 -07:00
Brian M. Carlson
b40918ddb8 Bump version 2014-03-30 00:10:18 -04:00
Brian C
b8946265c3 Merge pull request #8 from drob/handler-leak
Fixes an event handler leak.
2014-03-30 00:06:42 -04:00
Dan Robinson
d649905dbb Fixes an event handler leak.
Includes a test. Also includes async as a devDependency.
2014-03-28 04:19:19 -07:00
Brian C
22da85448e Merge pull request #7 from pensierinmusica/master
Update README.md
2014-03-27 20:43:46 -04:00
Alessandro Zanardi
531f72dcb3 Update README.md
Got rid of duplicate variable
2014-03-27 16:16:33 +01:00
Brian M. Carlson
dc6521b7c1 Fix to work with pg >= 2.8.2 2013-12-09 11:41:17 -05:00
Brian C
16e2001064 Update README.md 2013-11-08 00:49:19 -06:00
Brian C
5bb93308eb Update README.md 2013-11-08 00:47:52 -06:00
Brian C
e5f864bac0 Update README.md 2013-11-08 00:47:15 -06:00
Brian C
bfc0353d2c Update README.md 2013-11-08 00:43:41 -06:00
Brian C
90012d84d7 Update README.md 2013-11-08 00:42:43 -06:00
Brian C
808c284b55 Update README.md 2013-11-08 00:40:45 -06:00
Brian C
b48283f4aa Update README.md 2013-11-08 00:39:13 -06:00
Brian C
5c03015715 Update README.md 2013-11-08 00:38:30 -06:00
Brian C
18fa1fdeb3 Create README.md 2013-11-08 00:15:16 -06:00
7 changed files with 211 additions and 18 deletions

93
README.md Normal file
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@@ -0,0 +1,93 @@
## pg-copy-streams
COPY FROM / COPY TO for node-postgres. Stream from one database to another, and stuff.
## how? what? huh?
Did you know the _all powerful_ PostgreSQL supports streaming binary data directly into and out of a table?
This means you can take your favorite CSV or TSV or whatever format file and pipe it directly into an existing PostgreSQL table.
You can also take a table and pipe it directly to a file, another database, stdout, even to `/dev/null` if you're crazy!
What this module gives you is a [Readable](http://nodejs.org/api/stream.html#stream_class_stream_readable) or [Writable](http://nodejs.org/api/stream.html#stream_class_stream_writable) stream directly into/out of a table in your database.
This mode of interfacing with your table is _very fast_ and _very brittle_. You are responsible for properly encoding and ordering all your columns. If anything is out of place PostgreSQL will send you back an error. The stream works within a transaction so you wont leave things in a 1/2 borked state, but it's still good to be aware of.
If you're not familiar with the feature (I wasn't either) you can read this for some good helps: http://www.postgresql.org/docs/9.3/static/sql-copy.html
## examples
### pipe from a table to stdout
```js
var pg = require('pg');
var copyTo = require('pg-copy-streams').to;
pg.connect(function(err, client, done) {
var stream = client.query(copyTo('COPY my_table TO STDOUT'));
stream.pipe(process.stdout);
stream.on('end', done);
stream.on('error', done);
});
```
### pipe from a file to table
```js
var fs = require('fs');
var pg = require('pg');
var copyFrom = require('pg-copy-streams').from;
pg.connect(function(err, client, done) {
var stream = client.query(copyFrom('COPY my_table FROM STDIN'));
var fileStream = fs.createReadStream('some_file.tdv')
fileStream.pipe(stream);
fileStream.on('end', done);
fileStream.on('error', done);
});
```
## install
```sh
$ npm install pg-copy-streams
```
## notice
Before you set out on this magical piping journey, you _really_ should read this: http://www.postgresql.org/docs/9.3/static/sql-copy.html, and you might want to take a look at the [tests](https://github.com/brianc/node-pg-copy-streams/tree/master/test) to get an idea of how things work.
## contributing
Instead of adding a bunch more code to the already bloated [node-postgres](https://github.com/brianc/node-postgres) I am trying to make the internals extensible and work on adding edge-case features as 3rd party modules.
This is one of those.
Please, if you have any issues with this, open an issue.
Better yet, submit a pull request. I _love_ pull requests.
Generally how I work is if you submit a few pull requests and you're interested I'll make you a contributor and give you full access to everything.
Since this isn't a module with tons of installs and dependent modules I hope we can work together on this to iterate faster here and make something really useful.
## license
The MIT License (MIT)
Copyright (c) 2013 Brian M. Carlson
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

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@@ -8,18 +8,23 @@ var util = require('util')
var CopyStreamQuery = function(text) {
Transform.call(this)
this.text = text
this._listeners = null
this._listeners = {}
this._copyOutResponse = null
this.rowCount = 0
}
util.inherits(CopyStreamQuery, Transform)
var eventTypes = ['close', 'data', 'end', 'error']
CopyStreamQuery.prototype.submit = function(connection) {
connection.query(this.text)
this.connection = connection
this._listeners = connection.stream.listeners('data')
connection.stream.removeAllListeners('data')
var self = this
eventTypes.forEach(function(type) {
self._listeners[type] = connection.stream.listeners(type)
connection.stream.removeAllListeners(type)
})
connection.stream.pipe(this)
}
@@ -32,10 +37,12 @@ var code = {
CopyStreamQuery.prototype._detach = function() {
this.connection.stream.unpipe()
this.connection.stream.removeAllListeners('data')
var self = this
this._listeners.forEach(function(listener) {
self.connection.stream.on('data', listener)
eventTypes.forEach(function(type) {
self.connection.stream.removeAllListeners(type)
self._listeners[type].forEach(function(listener) {
self.connection.stream.on(type, listener)
})
})
}

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@@ -55,7 +55,7 @@ CopyStreamQuery.prototype.handleError = function(e) {
this.emit('error', e)
}
CopyStreamQuery.prototype.streamData = function(connection) {
CopyStreamQuery.prototype.handleCopyInResponse = function(connection) {
this.pipe(connection.stream)
}

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@@ -1,6 +1,6 @@
{
"name": "pg-copy-streams",
"version": "0.2.0",
"version": "0.2.3",
"description": "Low-Level COPY TO and COPY FROM streams for PostgreSQL in JavaScript using",
"main": "index.js",
"scripts": {
@@ -27,6 +27,7 @@
"concat-stream": "~1.1.0",
"gonna": "0.0.0",
"lodash": "~2.2.1",
"heroku-env": "~0.1.1"
"heroku-env": "~0.1.1",
"async": "~0.2.10"
}
}

65
test/binary.js Normal file
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@@ -0,0 +1,65 @@
var assert = require('assert')
var gonna = require('gonna')
var async = require('async')
var concat = require('concat-stream')
var _ = require('lodash')
var pg = require('pg.js')
var from = require('../').from
var to = require('../').to
var testBinaryCopy = function() {
var client = function() {
var client = new pg.Client()
client.connect()
return client
}
var fromClient = client()
var toClient = client()
queries = [
'CREATE TABLE data (num BIGINT, word TEXT)',
'INSERT INTO data (num, word) VALUES (1, \'hello\'), (2, \'other thing\'), (3, \'goodbye\')',
'CREATE TABLE data_copy (LIKE data INCLUDING ALL)'
]
async.eachSeries(queries, _.bind(fromClient.query, fromClient), function(err) {
assert.ifError(err)
var fromStream = fromClient.query(to('COPY (SELECT * FROM data) TO STDOUT BINARY'))
var toStream = toClient.query(from('COPY data_copy FROM STDIN BINARY'))
runStream = function(callback) {
fromStream.on('error', callback)
toStream.on('error', callback)
toStream.on('finish', callback)
fromStream.pipe(toStream)
}
runStream(function(err) {
assert.ifError(err)
toClient.query('SELECT * FROM data_copy ORDER BY num', function(err, res){
assert.equal(res.rowCount, 3, 'expected 3 rows but got ' + res.rowCount)
assert.equal(res.rows[0].num, 1)
assert.equal(res.rows[0].word, 'hello')
assert.equal(res.rows[1].num, 2)
assert.equal(res.rows[1].word, 'other thing')
assert.equal(res.rows[2].num, 3)
assert.equal(res.rows[2].word, 'goodbye')
queries = [
'DROP TABLE data',
'DROP TABLE data_copy'
]
async.each(queries, _.bind(fromClient.query, fromClient), function(err) {
assert.ifError(err)
fromClient.end()
toClient.end()
})
})
})
})
}
testBinaryCopy()

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@@ -1,20 +1,21 @@
var assert = require('assert')
var gonna = require('gonna')
var concat = require('concat-stream')
var _ = require('lodash')
var async = require('async')
var concat = require('concat-stream')
var pg = require('pg.js')
var copy = require('../').to
var client = function() {
var client = new pg.Client()
client.connect()
return client
}
var testRange = function(top) {
var client = function() {
var client = new pg.Client()
client.connect()
return client
}
var fromClient = client()
var copy = require('../').to
var txt = 'COPY (SELECT * from generate_series(0, ' + (top - 1) + ')) TO STDOUT'
var stream = fromClient.query(copy(txt))
@@ -32,3 +33,28 @@ var testRange = function(top) {
}
testRange(10000)
var testLeak = function(rounds) {
var fromClient = client()
var txt = 'COPY (SELECT 10) TO STDOUT'
var runStream = function(num, callback) {
var stream = fromClient.query(copy(txt))
stream.on('data', function(data) {
// Just throw away the data.
})
stream.on('end', callback)
stream.on('error', callback)
}
async.timesSeries(rounds, runStream, function(err) {
assert.equal(err, null)
assert.equal(fromClient.connection.stream.listeners('close').length, 0)
assert.equal(fromClient.connection.stream.listeners('data').length, 1)
assert.equal(fromClient.connection.stream.listeners('end').length, 2)
assert.equal(fromClient.connection.stream.listeners('error').length, 1)
fromClient.end()
})
}
testLeak(5)

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@@ -1,2 +1,3 @@
require('./copy-from')
require('./copy-to')
require('./binary')