Implements ability to press buttons.

Traverse object once for nil checks

README.md

@@ -0,0 +1,7 @@
+# webdriver
+
+A simple implementation of the pretty recent [W3C WebDriver spec](https://www.w3.org/TR/webdriver/).
+Currently Firefox is just about the only browser that supports it.
+
+I have coded this library during a livestream, do check that out to see how the library is used:
+https://www.youtube.com/watch?v=583BwZ7uSro&index=1&list=PLm-fq5xBdPkrMuVkPWuho7XzszB6kJ2My

src/webdriver.nim

@@ -1,4 +1,6 @@
-import httpclient, uri, json, tables
+# For reference, this is brilliant: https://github.com/jlipps/simple-wd-spec
+
+import httpclient, uri, json, tables, options, strutils, unicode
 
 type
   WebDriver* = ref object
@@ -43,12 +45,13 @@ proc createSession*(self: WebDriver): Session =
   # Check the readiness of the Web Driver.
   let resp = self.client.getContent($(self.url / "status"))
   let obj = parseJson(resp)
+  let ready = obj{"value", "ready"}
 
-  if obj{"value", "ready"}.isNil():
+  if ready.isNil():
     let msg = "Readiness message does not follow spec"
     raise newException(ProtocolException, msg)
 
-  if not obj{"value", "ready"}.getBool():
+  if not ready.getBool():
     raise newException(WebDriverException, "WebDriver is not ready")
 
   # Create our session.
@@ -56,10 +59,17 @@ proc createSession*(self: WebDriver): Session =
   let sessionResp = self.client.postContent($(self.url / "session"),
                                             $sessionReq)
   let sessionObj = parseJson(sessionResp)
-  if sessionObj{"value", "sessionId"}.isNil():
+  let sessionId = sessionObj{"value", "sessionId"}
+  if sessionId.isNil():
     raise newException(ProtocolException, "No sessionId in response to request")
 
-  return Session(id: sessionObj["value"]["sessionId"].getStr(), driver: self)
+  return Session(id: sessionId.getStr(), driver: self)
+
+proc close*(self: Session) =
+  let reqUrl = $(self.driver.url / "session" / self.id)
+  let resp = self.driver.client.request(reqUrl, HttpDelete)
+
+  let respObj = checkResponse(resp.body)
 
 proc navigate*(self: Session, url: string) =
   ## Instructs the session to navigate to the specified URL.
@@ -81,15 +91,20 @@ proc getPageSource*(self: Session): string =
   return respObj{"value"}.getStr()
 
 proc findElement*(self: Session, selector: string,
-                  strategy = CssSelector): Element =
+                  strategy = CssSelector): Option[Element] =
   let reqUrl = $(self.driver.url / "session" / self.id / "element")
   let reqObj = %*{"using": toKeyword(strategy), "value": selector}
-  let resp = self.driver.client.postContent(reqUrl, $reqObj)
+  let resp = self.driver.client.post(reqUrl, $reqObj)
+  if resp.status == Http404:
+    return none(Element)
 
-  let respObj = checkResponse(resp)
+  if resp.status != Http200:
+    raise newException(WebDriverException, resp.status)
+
+  let respObj = checkResponse(resp.body)
 
   for key, value in respObj["value"].getFields().pairs():
-    return Element(id: value.getStr(), session: self)
+    return some(Element(id: value.getStr(), session: self))
 
 proc getText*(self: Element): string =
   let reqUrl = $(self.session.driver.url / "session" / self.session.id /
@@ -99,6 +114,77 @@ proc getText*(self: Element): string =
 
   return respObj["value"].getStr()
 
+proc click*(self: Element) =
+  let reqUrl = $(self.session.driver.url / "session" / self.session.id / 
+                 "element" / self.id / "click")
+  let obj = %*{}
+  let resp = self.session.driver.client.post(reqUrl, $obj)
+  if resp.status != Http200:
+    raise newException(WebDriverException, resp.status)
+
+  discard checkResponse(resp.body)
+
+# Note: There currently is an open bug in geckodriver that causes DOM events not to fire when sending keys.
+# https://github.com/mozilla/geckodriver/issues/348
+proc sendKeys*(self: Element, text: string) =
+  let reqUrl = $(self.session.driver.url / "session" / self.session.id /
+                 "element" / self.id / "value")
+  let obj = %*{"text": text}
+  let resp = self.session.driver.client.post(reqUrl, $obj)
+  if resp.status != Http200:
+    raise newException(WebDriverException, resp.status)
+
+  discard checkResponse(resp.body)
+
+type
+  # https://w3c.github.io/webdriver/#keyboard-actions
+  Key* = enum
+    Unidentified = 0,
+    Cancel,
+    Help,
+    Backspace,
+    Tab,
+    Clear,
+    Return,
+    Enter,
+    Shift,
+    Control,
+    Alt,
+    Pause,
+    Escape
+
+proc toUnicode(key: Key): Rune =
+  Rune(0xE000 + ord(key))
+
+proc press*(self: Session, keys: varargs[Key]) =
+  let reqUrl = $(self.driver.url / "session" / self.id / "actions")
+  let obj = %*{"actions": [
+    {
+      "type": "key",
+      "id": "keyboard",
+      "actions": []
+    }
+  ]}
+  for key in keys:
+    obj["actions"][0]["actions"].elems.add(
+      %*{
+        "type": "keyDown",
+        "value": $toUnicode(key)
+      }
+    )
+    obj["actions"][0]["actions"].elems.add(
+      %*{
+        "type": "keyUp",
+        "value": $toUnicode(key)
+      }
+    )
+
+  let resp = self.driver.client.post(reqUrl, $obj)
+  if resp.status != Http200:
+    raise newException(WebDriverException, resp.status)
+
+  discard checkResponse(resp.body)
+
 when isMainModule:
   let webDriver = newWebDriver()
   let session = webDriver.createSession()
@@ -106,4 +192,6 @@ when isMainModule:
                   "Entertainment-System/dp/B073BVHY3F"
   session.navigate(amazonUrl)
 
-  echo session.findElement("#priceblock_ourprice").getText()
+  echo session.findElement("#priceblock_ourprice").get().getText()
+
+  session.close()

webdriver.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.1.0"
+version       = "0.2.0"
 author        = "Dominik Picheta"
 description   = "Implementation of the WebDriver w3c spec."
 license       = "MIT"