About

A very simple web server providing an HTTP interface to Redis. It uses hiredis, jansson and libevent.

make clean all
./webdis &
curl http://127.0.0.1:7379/SET/hello/world
→ {"SET":[true,"OK"]}
curl http://127.0.0.1:7379/GET/hello
→ {"GET":"world"}

curl -d "GET/hello" http://127.0.0.1:7379/
→ {"GET":"world"}

Features

• GET and POST are supported.
• JSON output by default, optional JSONP parameter (?jsonp=myFunction).
• Raw Redis 2.0 protocol output with .raw suffix
• HTTP 1.1 pipelining (50,000 http requests per second on a desktop Linux machine.)
• Connects to Redis using a TCP or UNIX socket.
• Restricted commands by IP range (CIDR subnet + mask) or HTTP Basic Auth, returning 403 errors.
• Possible Redis authentication in the config file.
• Pub/Sub using Transfer-Encoding: chunked, works with JSONP as well. Webdis can be used as a Comet server.
• Drop privileges on startup.
• Custom Content-Type using a pre-defined file extension.
• URL-encoded parameters for binary data or slashes. For instance, %2f is decoded as / but not used as a command separator.

Ideas, TODO...

• Support PUT, DELETE, HEAD, OPTIONS? How? For which commands?
• MULTI/EXEC/DISCARD/WATCH are disabled at the moment; find a way to use them.
• Add logs.
• Support POST of raw Redis protocol data, and execute the whole thing. This could be useful for MULTI/EXEC transactions.
• Enrich config file:
  • Provide timeout (this needs to be added to hiredis first.)
• Multi-server support, using consistent hashing.
• Add WebSocket support (with which protocol?)
• Allow cross-origin XHR.
• Allow file upload with PUT? Saving a file in Redis using the SET command should be easy to do with cURL.
• Send your ideas using the github tracker, on twitter @yowgi or by mail to n.favrefelix@gmail.com.

HTTP error codes

• Unknown HTTP verb: 405 Method Not Allowed
• Redis is unreachable: 503 Service Unavailable
• Matching ETag sent using If-None-Match: 304 Not Modified.
• Could also be used:
  • Timeout on the redis side: 503 Service Unavailable (this isn't supported by HiRedis yet).
  • Missing key: 404 Not Found.
  • Unauthorized command (disabled in config file): 403 Forbidden.

Command format

The URI /COMMAND/arg0/arg1/.../argN executes the command on Redis and returns the response to the client. GET and POST are supported:

• GET /COMMAND/arg0/.../argN
• POST / with COMMAND/arg0/.../argN in the HTTP body.

Special characters: / and . have special meanings, / separates arguments and . adds a file extension to change the Content-Type. They can be replaced by %2f and %2e, respectively.

ACL

Access control is configured in webdis.json. Each configuration tries to match a client profile according to two criterias:

• CIDR subnet + mask
• HTTP Basic Auth in the format of "user:password".

Each ACL contains two lists of commands, enabled and disabled. All commands being enabled by default, it is up to the administrator to disable or re-enable them on a per-profile basis. Examples:

{
	"disabled":	["DEBUG", "FLUSHDB", "FLUSHALL"],
},

{
	"http_basic_auth": "user:password",
	"disabled":	["DEBUG", "FLUSHDB", "FLUSHALL"],
	"enabled":	["SET"]
},

{
	"ip": 		"192.168.10.0/24",
	"enabled":	["SET"]
},

{
	"http_basic_auth": "user:password",
	"ip": 		"192.168.10.0/24",
	"enabled":	["SET", "DEL"]
}

ACLs are interpreted in order, later authorizations superseding earlier ones if a client matches several.

JSON output

JSON is the default output format. Each command returns a JSON object with the command as a key and the result as a value.

Examples:

// string
$ curl http://127.0.0.1:7379/GET/y
{"GET":"41"}

// number
$ curl http://127.0.0.1:7379/INCR/y
{"INCR":42}

// list
$ curl http://127.0.0.1:7379/LRANGE/x/0/1
{"LRANGE":["abc","def"]}

// status
$ curl http://127.0.0.1:7379/TYPE/y
{"TYPE":[true,"string"]}

// error, which is basically a status
$ curl http://127.0.0.1:7379/MAKE-ME-COFFEE
{"MAKE-ME-COFFEE":[false,"ERR unknown command 'MAKE-ME-COFFEE'"]}

// JSONP callback:
$ curl  "http://127.0.0.1:7379/TYPE/y?jsonp=myCustomFunction"
myCustomFunction({"TYPE":[true,"string"]})

RAW output

This is the raw output of Redis; enable it with the .raw suffix.

// string
$ curl http://127.0.0.1:7379/GET/z.raw
$5
hello

// number
curl http://127.0.0.1:7379/INCR/a.raw
:2

// list
$ curl http://127.0.0.1:7379/LRANGE/x/0/-1?.raw
*2
$3
abc
$3
def

// status
$ curl http://127.0.0.1:7379/TYPE/y.raw
+zset

// error, which is basically a status
$ curl http://127.0.0.1:7379/MAKE-ME-COFFEE.raw
-ERR unknown command 'MAKE-ME-COFFEE'

Custom content-type

Several content-types are available: * .json for application/json (this is the default Content-Type). * .txt for text/plain * .html for text/html * .png for image/png

curl -v "http://127.0.0.1:7379/GET/hello.html"	# the key is “hello” here, not “hello.html”
[...]
< HTTP/1.1 200 OK
< Content-Type: text/html
< Date: Mon, 03 Jan 2011 20:43:36 GMT
< Content-Length: 137
<
<!DOCTYPE html>
<html>
...
</html>