umputun/reproxy

Simple edge server / reverse proxy

Reproxy is a simple edge HTTP(s) server / reverse proxy supporting various providers (docker, static, file). One or more providers supply information about requested server, requested url, destination url and health check url. Distributed as a single binary or as a docker container.

• Automatic SSL termination with Let’s Encrypt
• Support of user-provided SSL certificates
• Simple but flexible proxy rules
• Static, command line proxy rules provider
• Dynamic, file-based proxy rules provider
• Docker provider with an automatic discovery
• Optional traffic compression
• User-defined limits and timeouts
• Single binary distribution
• Docker container distribution
• Built-in static assets server

Server can be set as FQDN, i.e. s.example.com or * (catch all). Requested url can be regex, for example ^/api/(.*) and destination url may have regex matched groups in, i.e. http://d.example.com:8080/$1. For the example above http://s.example.com/api/something?foo=bar will be proxied to http://d.example.com:8080/something?foo=bar.

For convenience, requests with the trailing / and without regex groups expanded to /(.*), and destinations in those cases expanded to /$1. I.e. /api/ -> http://127.0.0.1/service will be translated to ^/api/(.*) -> http://127.0.0.1/service/$1

Both HTTP and HTTPS supported. For HTTPS, static certificate can be used as well as automated ACME (Let’s Encrypt) certificates. Optional assets server can be used to serve static files.

Starting reproxy requires at least one provider defined. The rest of parameters are strictly optional and have sane default.

Example with a static provider: reproxy --static.enabled --static.rule="example.com/api/(.*),https://api.example.com/$1" Example with an automatic docker discovery: reproxy --docker.enabled --docker.auto

Install

• for a binary distribution pick the proper file in the release section
• docker container available on Docker Hub as well as on Github Container Registry.

Latest stable version has :vX.Y.Z tag (with :latest alias) and the current master has :master tag.

Providers

Proxy rules supplied by various providers. Currently included file, docker and static. Each provider may define multiple routing rules for both proxied request and static (assets). User can sets multiple providers at the same time.

See examples of various providers in examples

Static

This is the simplest provider defining all mapping rules directly in the command line (or environment). Multiple rules supported. Each rule is 3 or 4 comma-separated elements server,sourceurl,destination,[ping-url]. For example:

• *,^/api/(.*),https://api.example.com/$1, - proxy all request to any host/server with /api prefix to https://api.example.com
• example.com,/foo/bar,https://api.example.com/zzz,https://api.example.com/ping - proxy all requests to example.com and with /foo/bar url to https://api.example.com/zzz. Uses https://api.example.com/ping for the health check

The last (4th) element defines an optional ping url used for health reporting. I.e.*,^/api/(.*),https://api.example.com/$1,https://api.example.com/ping. See Health check section for more details.

File

reproxy --file.enabled --file.name=config.yml

Example of config.yml:

default: # the same as * (catch-all) server
  - { route: "^/api/svc1/(.*)", dest: "http://127.0.0.1:8080/blah1/$1" }
  - {
      route: "/api/svc3/xyz",
      dest: "http://127.0.0.3:8080/blah3/xyz",
      "ping": "http://127.0.0.3:8080/ping",
    }
srv.example.com:
  - { route: "^/api/svc2/(.*)", dest: "http://127.0.0.2:8080/blah2/$1/abc" }

This is a dynamic provider and file change will be applied automatically.

Docker

Docker provider supports a fully automatic discovery (with --docker.auto) with no extra configuration and by default redirects all requests like https://server/<container_name>/(.*) to the internal IP of the given container and the exposed port. Only active (running) containers will be detected.

This default can be changed with labels:

• reproxy.server - server (hostname) to match. Also can be a list of comma-separated servers.
• reproxy.route - source route (location)
• reproxy.dest - destination path. Note: this is not full url, but just the path which will be appended to container’s ip:port
• reproxy.port - destination port for the discovered container
• reproxy.ping - ping path for the destination container.
• reproxy.enabled - enable (yes, true, 1) or disable (no, false, 0) container from reproxy destinations.

Pls note: without --docker.auto the destination container has to have at least one of reproxy.* labels to be considered as a potential destination.

With --docker.auto, all containers with exposed port will be considered as routing destinations. There are 3 ways to restrict it:

• Exclude some containers explicitly with --docker.exclude, i.e. --docker.exclude=c1 --docker.exclude=c2 ...
• Allow only a particular docker network with --docker.network
• Set the label reproxy.enabled=false or reproxy.enabled=no or reproxy.enabled=0

This is a dynamic provider and any change in container’s status will be applied automatically.

SSL support

SSL mode (by default none) can be set to auto (ACME/LE certificates), static (existing certificate) or none. If auto turned on SSL certificate will be issued automatically for all discovered server names. User can override it by setting --ssl.fqdn value(s)

Logging

By default no request log generated. This can be turned on by setting --logger.enabled. The log (auto-rotated) has Apache Combined Log Format

User can also turn stdout log on with --logger.stdout. It won’t affect the file logging but will output some minimal info about processed requests, something like this:

2021/04/16 01:17:25.601 [INFO]  GET - /echo/image.png - xxx.xxx.xxx.xxx - 200 (155400) - 371.661251ms
2021/04/16 01:18:18.959 [INFO]  GET - /api/v1/params - xxx.xxx.xxx.xxx - 200 (74) - 1.217669m

Assets Server

User may turn assets server on (off by default) to serve static files. As long as --assets.location set it will treat every non-proxied request under assets.root as a request for static files. Assets server can be used without any proxy providers. In this mode reproxy acts as a simple web server for a static context.

In addition to the common assets server multiple custom static servers supported. Each provider has a different way to define such static rule and some providers may not support it at all. For example, multiple static server make sense in case of static (command line provide), file provider and can be even useful with docker provider.

1. static provider - if source element prefixed by assets: it will be treated as file-server. For example *,assets:/web,/var/www, will serve all /web/* request with a file server on top of /var/www directory.
2. file provider - setting optional field assets: true
3. docker provider - reproxy.assets=web-root:location, i.e. reproxy.assets=/web:/var/www.

More options

• --gzip enables gizp compression for responses.
• --max=N allows to set the maximum size of request (default 64k)
• --header sets extra header(s) added to each proxied request
• --timeout.* various timeouts for both server and proxy transport. See timeout section in All Application Options

Ping and health checks

reproxy provides 2 endpoints for this purpose:

• /ping responds with pong and indicates what reproxy up and running
• /health returns 200 OK status if all destination servers responded to their ping request with 200 or 417 Expectation Failed if any of servers responded with non-200 code. It also returns json body with details about passed/failed services.

All Application Options

  -l, --listen=                     listen on host:port (default: 127.0.0.1:8080) [$LISTEN]
  -m, --max=                        max response size (default: 64000) [$MAX_SIZE]
  -g, --gzip                        enable gz compression [$GZIP]
  -x, --header=                     proxy headers [$HEADER]
      --signature                   enable reproxy signature headers [$SIGNATURE]
      --dbg                         debug mode [$DEBUG]

ssl:
      --ssl.type=[none|static|auto] ssl (auto) support (default: none) [$SSL_TYPE]
      --ssl.cert=                   path to cert.pem file [$SSL_CERT]
      --ssl.key=                    path to key.pem file [$SSL_KEY]
      --ssl.acme-location=          dir where certificates will be stored by autocert manager (default: ./var/acme) [$SSL_ACME_LOCATION]
      --ssl.acme-email=             admin email for certificate notifications [$SSL_ACME_EMAIL]
      --ssl.http-port=              http port for redirect to https and acme challenge test (default: 80) [$SSL_HTTP_PORT]
      --ssl.fqdn=                   FQDN(s) for ACME certificates [$SSL_ACME_FQDN]

assets:
  -a, --assets.location=            assets location [$ASSETS_LOCATION]
      --assets.root=                assets web root (default: /) [$ASSETS_ROOT]

logger:
      --logger.stdout               enable stdout logging [$LOGGER_STDOUT]
      --logger.enabled              enable access and error rotated logs [$LOGGER_ENABLED]
      --logger.file=                location of access log (default: access.log) [$LOGGER_FILE]
      --logger.max-size=            maximum size in megabytes before it gets rotated (default: 100) [$LOGGER_MAX_SIZE]
      --logger.max-backups=         maximum number of old log files to retain (default: 10) [$LOGGER_MAX_BACKUPS]

docker:
      --docker.enabled              enable docker provider [$DOCKER_ENABLED]
      --docker.host=                docker host (default: unix:///var/run/docker.sock) [$DOCKER_HOST]
      --docker.network=             docker network [$DOCKER_NETWORK]
      --docker.exclude=             excluded containers [$DOCKER_EXCLUDE]
      --docker.auto                 enable automatic routing (without labels) [$DOCKER_AUTO]

file:
      --file.enabled                enable file provider [$FILE_ENABLED]
      --file.name=                  file name (default: reproxy.yml) [$FILE_NAME]
      --file.interval=              file check interval (default: 3s) [$FILE_INTERVAL]
      --file.delay=                 file event delay (default: 500ms) [$FILE_DELAY]

static:
      --static.enabled              enable static provider [$STATIC_ENABLED]
      --static.rule=                routing rules [$STATIC_RULES]

timeout:
      --timeout.read-header=        read header server timeout (default: 5s) [$TIMEOUT_READ_HEADER]
      --timeout.write=              write server timeout (default: 30s) [$TIMEOUT_WRITE]
      --timeout.idle=               idle server timeout (default: 30s) [$TIMEOUT_IDLE]
      --timeout.dial=               dial transport timeout (default: 30s) [$TIMEOUT_DIAL]
      --timeout.keep-alive=         keep-alive transport timeout (default: 30s) [$TIMEOUT_KEEP_ALIVE]
      --timeout.resp-header=        response header transport timeout (default: 5s) [$TIMEOUT_RESP_HEADER]
      --timeout.idle-conn=          idle connection transport timeout (default: 90s) [$TIMEOUT_IDLE_CONN]
      --timeout.tls=                TLS hanshake transport timeout (default: 10s) [$TIMEOUT_TLS]
      --timeout.continue=           expect continue transport timeout (default: 1s) [$TIMEOUT_CONTINUE]

Help Options:
  -h, --help                        Show this help message

Status

The project is under active development and may have breaking changes till v1 released.