Hi, Here is a little tool that might be useful to some you. For others it might be a nice example. So you have your shiny Pharo server application running in the cloud. When something goes wrong, most of the time you will just restart, manually or automatically. But sometimes you wish you could interact with a running headless server image. Problem is, you can't out of the box. ZnReadEvalPrintDelegate is a simple tool that exports a REPL Web Service. Much like the emergency evaluator. Primitive but better than nothing. Install it on a port of your choice, running in a independent Zn HTTP server, bound to localhost only. ZnReadEvalPrintDelegate startInServerOn: 1701. There is only one API method: POST a plain/text Smalltalk expression to evaluate, get the result back. ZnClient new url: 'http://localhost:1701/repl'; contents: '42 factorial'; post. Here is an example terminal session (logged in to the server, not remote): A GET on the service /repl gives some help text $ curl http://localhost:1701/repl # Pharo Smalltalk REPL. POST expressions to evaluate # Here is one way (type ctrl-d to end input) curl -X POST -H'Content-Type:text/plain' --data-binary @- http://localhost:1701/repl A POST with -d is good for short expressions $ curl -X POST -H'Content-Type:text/plain' -d '42 factorial' http://localhost:1701/repl 1405006117752879898543142606244511569936384000000000 For longer or multi line expressions you can read input from stdin and end with ctrl-d (copy the expression returned by the GET). Or you could send text files. $ curl -X POST -H'Content-Type:text/plain' --data-binary @- http://localhost:1701/repl { (1 to: 10) sum. (1 to: 10) average } {55. (11/2)} There is error handling as well: $ curl -X POST -H'Content-Type:text/plain' --data-binary @- http://localhost:1701/repl 1 plus: 2 MessageNotUnderstood: SmallInteger>>plus: SmallInteger(Object)>>doesNotUnderstand: #plus: Receiver: 1 Arguments and temporary variables: aMessage: plus: 2 exception: MessageNotUnderstood: SmallInteger>>plus: resumeValue: nil Receiver's instance variables: 1 UndefinedObject>>DoIt Compiler>>evaluate:in:to:notifying:ifFail:logged: Compiler>>evaluate:in:to:notifying:ifFail: Compiler>>evaluate:in:to: ZnReadEvalPrintDelegate>>evaluate: in Block: [| result |... BlockClosure>>on:do: ZnReadEvalPrintDelegate>>evaluate: in Block: [:out | [| result |... String class(SequenceableCollection class)>>new:streamContents: WARNING: never open this service beyond your local network ! This service gives you absolute control over and access to everything in your image. For example, the following will kill your image: $ curl -X POST -H'Content-Type:text/plain' -d 'Smalltalk quitPrimitive' http://localhost:1701/repl All this in one class and a handful of methods. Enjoy, Sven PS1: Part of Zinc HTTP Components, in the bleedingEdge version. PS2: Of course, basic authentication or HTTPS can be added through simple Zn configuration. -- Sven Van Caekenberghe Proudly supporting Pharo http://pharo.org http://association.pharo.org http://consortium.pharo.org