planning

node_modules/semaphore/README.md

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+semaphore.js
+============
+
+[![Build Status](https://travis-ci.org/abrkn/semaphore.js.svg?branch=master)](https://travis-ci.org/abrkn/semaphore.js)
+
+Install:
+npm install semaphore
+
+Limit simultaneous access to a resource.
+
+```javascript
+// Create
+var sem = require('semaphore')(capacity);
+
+// Take
+sem.take(fn[, n=1])
+sem.take(n, fn)
+
+// Leave
+sem.leave([n])
+
+// Available
+sem.available([n])
+```
+
+
+```javascript
+// Limit concurrent db access
+var sem = require('semaphore')(1);
+var server = require('http').createServer(req, res) {
+	sem.take(function() {
+		expensive_database_operation(function(err, res) {
+			sem.leave();
+
+			if (err) return res.end("Error");
+
+			return res.end(res);
+		});
+	});
+});
+```
+
+```javascript
+// 2 clients at a time
+var sem = require('semaphore')(2);
+var server = require('http').createServer(req, res) {
+	res.write("Then good day, madam!");
+
+	sem.take(function() {
+		res.end("We hope to see you soon for tea.");
+		sem.leave();
+	});
+});
+```
+
+```javascript
+// Rate limit
+var sem = require('semaphore')(10);
+var server = require('http').createServer(req, res) {
+	sem.take(function() {
+		res.end(".");
+		
+		setTimeout(sem.leave, 500)
+	});
+});
+```
+
+License
+===
+
+MIT