HTTP AccessDownlad Files via HTTPYou can download files via HTTP protocol using a generic stream-copy function copy. Below is the example. import(net.http) copy('http://sourceforge.jp/', 'sf.html') If you want to use a proxy server, you need to specify a server setting using net.http.addproxy like follows. import(net.http) net.http.addproxy('xx.xx.xx.xx', 8080, 'username', 'password') copy('http://sourceforge.jp/', 'sf.html') Read CSV File via HTTPThe following example reads a CSV file in the SVN repository via HTTP protocol and prints contents of it. import(csv) import(net.http) uri = 'http://sourceforge.jp/projects/gura/svn/view/trunk/' \ 'test/50records-en.csv?view=co&root=gura' Person = struct(name:string, email:string, gender:string, age:number, rest*) people = Person * csv.reader(uri):iter println(people) The method csv#read(), which reads contents of a CSV file, doesn't have any idea about HTTP by itself. Gura language engine analyzes the path name, calls a stream-creating function of an appropriate module depending on it, net.http for the above case, and then passes the stream instance to csv#read() method. If you implement a function to receive a stream as its argument, it's automatically being capable of handling protocols like HTTP and accessing various type of data structures. Database Access and HTTP ProtocolThe following example works as a HTTP server, which generates a graph that shows values in SQLite3 database. After the script runs, it waits for HTTP requests. Launch a Web browser and access to it as like http://localhost/?site=0,1. If you try it on Linux, you have to run the script as a root user or replace the port number with one larger than or equal to 1024. import(re) import(cairo) import(net.http) import(png) import(sqlite3) makeGraph(iSites[]:number) = { tbl = struct(day:number, temps*:number) * \ sqlite3.db('temperature.sqlite3').query('select * from sites') img = image(`rgba, 320, 320, `white) [wdAxis, htAxis] = [img.width * 0.9, img.height * 0.9] [xAxis, yAxis] = [(img.width - wdAxis) / 2, (img.height - htAxis) / 2] [dayMax, dayMin] = [tbl:*day.max(), tbl:*day.min()] dayRange = dayMax - dayMin [tempMax, tempMin] = [tbl:*temps:*max().max(), tbl:*temps:*min().min()] tempRange = tempMax - tempMin calcX(day) = xAxis + (day - dayMin) * wdAxis / dayRange calcY(temp) = yAxis + htAxis - (temp - tempMin) * htAxis / tempRange img.cairo {|cr| cr.set_line_width(img.height / 300) cr.rectangle(xAxis, yAxis, wdAxis, htAxis).stroke() cr.save { cr.set_dash([img.height / 200, img.height / 200], 0) cr.move_to(xAxis, calcY(0)).line_to(xAxis + wdAxis, calcY(0)) cr.stroke() } for (iSite in iSites) { func = cr.move_to for (item in tbl) { func(calcX(item.day), calcY(item.temps[iSite])) func = cr.line_to } cr.stroke() } } img } net.http.server(port => 80).wait {|req| iSites = [0] query = net.http.parsequery(req.query) if (query.haskey('site')) { iSites = tonumber(query['site'].split(','):list) } buff = binary() makeGraph(iSites).pngwrite(buff) req.response('200', nil, buff, 'Server' => 'Gura_HTTP_Server' 'Connection' => 'close') } |