Get curl command line for a request

http/request.lua

@@ -167,6 +167,146 @@ function request_methods:to_uri(with_userinfo)
 	return scheme .. "://" .. authority .. path
 end
 
+function request_methods:to_curl()
+	local cmd = {
+		"curl";
+	}
+	local n = 1
+
+	if self.version then
+		if self.version == 1 then
+			cmd[n+1] = "-0"
+		elseif self.version == 1.1 then
+			cmd[n+1] = "--http1.1"
+		elseif self.version == 2 then
+			cmd[n+1] = "--http2"
+		else
+			error("invalid version")
+		end
+		n = n + 1
+	end
+
+	if self.proxy then
+		if type(self.proxy) ~= "string" then
+			error("NYI")
+		end
+		cmd[n+1] = "--proxy"
+		cmd[n+2] = self.proxy
+		n = n + 2
+	elseif not self.proxies then
+		cmd[n+1] = "--noproxy"
+		cmd[n+2] = "*"
+		n = n + 2
+	elseif self.proxies ~= default_proxies then
+		assert(getmetatable(self.proxies) == http_proxies.mt, "proxies property should be a http.proxies object")
+		error("NYI")
+	end
+
+	if self.expect_100_timeout ~= 1 then
+		cmd[n+1] = "--expect100-timeout"
+		cmd[n+2] = string.format("%d", self.expect_100_timeout)
+		n = n + 2
+	end
+
+	if self.follow_redirects then
+		cmd[n+1] = "--location-trusted"
+		cmd[n+2] = "-e"
+		cmd[n+3] = ";auto"
+		n = n + 3
+
+		if self.max_redirects ~= 50 then -- curl default is 50
+			cmd[n+1] = "--max-redirs"
+			cmd[n+2] = string.format("%d", self.max_redirects or -1)
+			n = n + 2
+		end
+
+		if self.post301 then
+			cmd[n+1] = "--post301"
+			n = n + 1
+		end
+
+		if self.post302 then
+			cmd[n+1] = "--post302"
+			n = n + 1
+		end
+	end
+
+	if self.tls and self.tls ~= true then
+		error("NYI")
+	end
+
+	local scheme = self.headers:get(":scheme")
+	-- Unlike the ':to_uri' method, curl needs the authority in the URI to be the actual host/port
+	local authority = http_util.to_authority(self.host, self.port, scheme)
+	local path = self.headers:get(":path")
+	assert(path == "" or path:sub(1,1) == "/" or path:sub(1,1) == "?", "invalid path for cURL")
+	local url = scheme .. "://" .. authority .. path
+	if url:match("[%[%]%{%}]") then
+		-- Turn off curl URL globbing
+		cmd[n+1] = "-g"
+		n = n + 1
+	end
+	cmd[n+1] = url
+	n = n + 1
+
+	for name, value in self.headers:each() do
+		if name:sub(1,1) == ":" then
+			if name == ":authority" then
+				if value ~= authority then
+					cmd[n+1] = "-H"
+					cmd[n+2] = "host: " .. value
+					n = n + 2
+				end
+			elseif name == ":method" then
+				if value == "HEAD" then
+					cmd[n+1] = "-I"
+					n = n + 1
+				elseif (value ~= "GET" or self.body ~= nil) and (value ~= "POST" or self.body == nil) then
+					cmd[n+1] = "-X"
+					cmd[n+2] = value
+					n = n + 2
+				end
+			end
+		elseif name == "user-agent" then
+			cmd[n+1] = "-A"
+			cmd[n+2] = value
+			n = n + 2
+		elseif name == "referer" then
+			cmd[n+1] = "-e"
+			assert(not value:match(";"), "cannot render referer")
+			if self.follow_redirects then
+				cmd[n+2] = value .. ";auto"
+			else
+				cmd[n+2] = value
+			end
+			n = n + 2
+		else
+			cmd[n+1] = "-H"
+			cmd[n+2] = name .. ": " .. value
+			n = n + 2
+		end
+	end
+
+	if self.body then
+		if type(self.body) == "string" then
+			cmd[n+1] = "--data-raw"
+			cmd[n+2] = self.body
+			n = n + 2
+		else
+			error("NYI")
+		end
+	end
+
+	-- escape ready for a command line
+	for i=1, n do
+		local arg = cmd[i]
+		if arg:match("[^%w%_%:%/%@%^%.%-]") then
+			cmd[i] = "'" .. arg:gsub("'", "'\\''") .. "'"
+		end
+	end
+	return table.concat(cmd, " ", 1, n)
+end
+
 function request_methods:handle_redirect(orig_headers)
 	local max_redirects = self.max_redirects
 	if max_redirects <= 0 then

spec/request_spec.lua

@@ -157,6 +157,131 @@ describe("http.request module", function()
 		test("https://foo:[email protected]:1234")
 		assert.has.errors(function() test("https://example.com/path") end)
 	end)
+	describe(":to_curl() #curl", function()
+		it("lua-http defaults", function()
+			local req = request.new_from_uri("http://example.com/")
+			req.headers:delete "user-agent" -- take variability out of tests
+			assert.same("curl --location-trusted -e ';auto' --max-redirs 5 http://example.com/", req:to_curl())
+		end)
+		local req_template = request.new_from_uri("http://example.com/")
+		req_template.headers:delete "user-agent" -- take variability out of tests
+		req_template.follow_redirects = false -- closer to curl defaults
+		req_template.max_redirects = 50
+		it("curl defaults", function()
+			local req = req_template:clone()
+			assert.same("curl http://example.com/", req:to_curl())
+		end)
+		it("http version 1.0", function()
+			local req = req_template:clone()
+			req.version = 1
+			assert.same("curl -0 http://example.com/", req:to_curl())
+		end)
+		it("http version 1.1", function()
+			local req = req_template:clone()
+			req.version = 1.1
+			assert.same("curl --http1.1 http://example.com/", req:to_curl())
+		end)
+		it("http version 2", function()
+			local req = req_template:clone()
+			req.version = 2
+			assert.same("curl --http2 http://example.com/", req:to_curl())
+		end)
+		it("expect_100_timeout flag", function()
+			local req = req_template:clone()
+			req.expect_100_timeout = 2
+			assert.same("curl --expect100-timeout 2 http://example.com/", req:to_curl())
+		end)
+		it("post301 flag", function()
+			local req = req_template:clone()
+			req.follow_redirects = nil
+			req.post301 = true
+			assert.same("curl --location-trusted -e ';auto' --post301 http://example.com/", req:to_curl())
+		end)
+		it("post302 flag", function()
+			local req = req_template:clone()
+			req.follow_redirects = nil
+			req.post302 = true
+			assert.same("curl --location-trusted -e ';auto' --post302 http://example.com/", req:to_curl())
+		end)
+		it("path component", function()
+			local req = req_template:clone()
+			req.headers:upsert(":path", "/[complex]&path{component}")
+			assert.same("curl -g 'http://example.com/[complex]&path{component}'", req:to_curl())
+		end)
+		it("query component", function()
+			local req = req_template:clone()
+			req.headers:upsert(":path", "/path?query")
+			assert.same("curl 'http://example.com/path?query'", req:to_curl())
+		end)
+		it("scheme change", function()
+			local req = req_template:clone()
+			req.headers:upsert(":scheme", "https")
+			assert.same("curl https://example.com:80/ -H 'host: example.com'", req:to_curl())
+		end)
+		it("scheme and port change", function()
+			local req = req_template:clone()
+			req.headers:upsert(":scheme", "https")
+			req.port = 443
+			assert.same("curl https://example.com/", req:to_curl())
+		end)
+		it("port change", function()
+			local req = req_template:clone()
+			req.port = 443
+			assert.same("curl http://example.com:443/ -H 'host: example.com'", req:to_curl())
+		end)
+		it("host change", function()
+			local req = req_template:clone()
+			req.headers:upsert(":authority", "foo.com")
+			assert.same("curl http://example.com/ -H 'host: foo.com'", req:to_curl())
+		end)
+		it("proxy", function()
+			local req = req_template:clone()
+			req.proxy = "http://foo.com"
+			assert.same("curl --proxy http://foo.com http://example.com/", req:to_curl())
+		end)
+		it("proxies", function()
+			local req = req_template:clone()
+			req.proxies = false
+			assert.same("curl --noproxy '*' http://example.com/", req:to_curl())
+		end)
+		it("head method", function()
+			local req = req_template:clone()
+			req.headers:upsert(":method", "HEAD")
+			assert.same("curl http://example.com/ -I", req:to_curl())
+		end)
+		it("post method with body", function()
+			local req = req_template:clone()
+			req.headers:upsert(":method", "POST")
+			req.body = "foo"
+			assert.same("curl http://example.com/ --data-raw foo", req:to_curl())
+		end)
+		it("post method without body", function()
+			local req = req_template:clone()
+			req.headers:upsert(":method", "POST")
+			assert.same("curl http://example.com/ -X POST", req:to_curl())
+		end)
+		it("referer header", function()
+			local req = req_template:clone()
+			req.headers:upsert("user-agent", "myuseragent")
+			assert.same("curl http://example.com/ -A myuseragent", req:to_curl())
+		end)
+		it("referer header", function()
+			local req = req_template:clone()
+			req.headers:upsert("referer", "foo.com")
+			assert.same("curl http://example.com/ -e foo.com", req:to_curl())
+		end)
+		it("referer header when follow_redirects is on", function()
+			local req = req_template:clone()
+			req.headers:upsert("referer", "foo.com")
+			req.follow_redirects = nil
+			assert.same("curl --location-trusted -e ';auto' http://example.com/ -e 'foo.com;auto'", req:to_curl())
+		end)
+		it("custom headers", function()
+			local req = req_template:clone()
+			req.headers:append("foo", "bar")
+			assert.same("curl http://example.com/ -H 'foo: bar'", req:to_curl())
+		end)
+	end)
 	it(":set_body sets content-length for string arguments", function()
 		local req = request.new_from_uri("http://example.com")
 		assert.falsy(req.headers:has("content-length"))