igo/docs/guide/cache.md

Igo is a Node.js Web Framework based on Express

# Igo.js cache

Igo.js uses Redis as a distributed cache.

This is the default Redis configuration :
```js

var retryStrategy = function(params) {
  if (params.error.code === 'ECONNREFUSED') {
    logger.error('Redis connection refused on host ' + options.host + ':' + options.port);
    return params.error;
  }
  logger.error('Redis error ' + params.error);
  // retry in n seconds
  return params.attempt * 1000;
};

config.redis = {
  host:     process.env.REDIS_HOST      || '127.0.0.1',
  port:     process.env.REDIS_PORT      || 6379,
  database: process.env.REDIS_DATABASE  || 0,
  timeout:        null,  // no timeout by default
  no_ready_check: true,
  retry_strategy: retryStrategy
};
```

This configuration object is directly transmitted to the redis client: `redisclient = redis.createClient(config.redis);`

Use `require('igo').cache` to access the Igo.js Cache API.

```js

var cache = require('igo').cache;
var id    = 123;
cache.put('namespace', id, 'hello', () => {
  const value = await cache.get('namespace', 124);
  assert(value === 'hello');
});

```

## API
Available functions are:
- `async get(namespace, id);`
- `async put(namespace, id, value);`
- `async fetch(namespace, id, fn);`  (where fn(id) is called only if key is not found in cache)
- `async info()`
- `async del(namespace, id)`
- `async flushall()`

## Special note about Dates
Since javascript Dates are ISO_8601 formatted and stored as strings in Redis, Igo.js automatically parses dates when they are retrieved from the cache.