A step by step guide to creating a DSL to test rest web services. I presented this talk to the Scala Days in Berlin the 18th of June 2014 http://www.scaladays.org/#schedule/RESTTest--exploring-DSL-design-in-Scala Watch this presentation online https://www.parleys.com/play/53a7d2d1e4b0543940d9e56c

1. REST Test
Exploring DSL design in Scala

2. Who am I?
Iain Hull
Email: iain.hull@workday.com
Twitter: @IainHull
Web: http://IainHull.github.io
Workday

3. HTTP Clients … What’s the problem?
http://www.hdwpapers.com/pretty_face_of_boxer_dog_wallpaper_hd-wallpapers.html

4. Simple HTTP Client
case class Request(
method: Method,
url: URI,
headers: Map[String, List[String]],
body: Option[String])
case class Response(
statusCode: Int,
headers: Map[String, List[String]],
body: Option[String])
type HttpClient = Request => Response

5. Simple HTTP Client
case class Request(
method: Method,
url: URI,
headers: Map[String, List[String]],
body: Option[String])
case class Response(
statusCode: Int,
headers: Map[String, List[String]],
body: Option[String])
type HttpClient = Request => Response

6. Simple HTTP Client
case class Request(
method: Method,
url: URI,
headers: Map[String, List[String]],
body: Option[String])
case class Response(
statusCode: Int,
headers: Map[String, List[String]],
body: Option[String])
type HttpClient = Request => Response

7. Simple HTTP Client
case class Request(
method: Method,
url: URI,
headers: Map[String, List[String]],
body: Option[String])
case class Response(
statusCode: Int,
headers: Map[String, List[String]],
body: Option[String])
type HttpClient = Request => Response

8. Using the Client
val request = Request(
GET,
new URI("http://api.rest.org/person",
Map(), None))
val response = httpClient(request)
assert(response.code1 === Status.OK)
assert(jsonAsList[Person](response.body.get) ===
EmptyList)

9. Using the Client
val request = Request(
GET,
new URI("http://api.rest.org/person",
Map(), None))
val response = httpClient(request)
assert(response.code === Status.OK)
assert(jsonAsList[Person](response.body.get) ===
EmptyList)

10. Using the Client
val request = Request(
GET,
new URI("http://api.rest.org/person",
Map(), None))
val response = httpClient(request)
assert(response.code === Status.OK)
assert(jsonAsList[Person](response.body.get) ===
EmptyList)

11. Using the Client
val request = Request(
GET,
new URI("http://api.rest.org/person",
Map(), None))
val response = httpClient(request)
assert(response.code === Status.OK)
assert(jsonAsList[Person](response.body.get) ===
EmptyList)

12. Sample API
GET /person List all the persons
POST /person Create a new person
GET /person/{id} Retrieve a person
DELETE /person/{id} Delete a person

13. Retrieve the list
GET /person Verify list is empty

14. Create a new person
GET /person Verify list is empty
POST /person Verify it succeeds and returns an id

15. Retrieve the person
GET /person Verify list is empty
POST /person Verify it succeeds and returns an id
GET /person/{id} Verify details are the same

16. Retrieve the list
GET /person Verify list is empty
POST /person Verify it succeeds and returns an id
GET /person/{id} Verify details are the same
GET /person Verify list contains the person

17. Delete the person
GET /person Verify list is empty
POST /person Verify it succeeds and returns an id
GET /person/{id} Verify details are the same
GET /person Verify list contains the person
DELETE /person/{id} Verify the status code

18. Retrieve the list
GET /person Verify list is empty
POST /person Verify it succeeds and returns an id
GET /person/{id} Verify details are the same
GET /person Verify list contains the person
DELETE /person/{id} Verify the status code
GET /person Verify list is empty

19. val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

20. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head

21. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))

22. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

23. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))

24. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

25. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r1.statusCode === Status.OK)
r1.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
assert(r2.statusCode === Status.Created)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r3.statusCode === Status.OK)
r3.body match {
Some(body) =>
assert(jsonAs[Person](body) === Jason)
None => fail("Expected a body"))
}
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r4.statusCode === Status.OK)
r4.body match {
Some(body) =>
assert(jsonAsList[Person](body) === Seq(Jason))
None => fail("Expected a body"))
}
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r5.statusCode === Status.OK)
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r6.statusCode === Status.OK)
r6.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}

26. Agh!!
I can’t read
this

27. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r1.statusCode === Status.OK)
r1.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
assert(r2.statusCode === Status.Created)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r3.statusCode === Status.OK)
r3.body match {
Some(body) =>
assert(jsonAs[Person](body) === Jason)
None => fail("Expected a body"))
}
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r4.statusCode === Status.OK)
r4.body match {
Some(body) =>
assert(jsonAsList[Person](body) === Seq(Jason))
None => fail("Expected a body"))
}
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r5.statusCode === Status.OK)
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r6.statusCode === Status.OK)
r6.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}

28. New Code
Modifying
Code
Reading Code
http://www.codinghorror.com/blog/2006/09/when-understanding-means-rewriting.html

29. http://www.flickr.com/photos/paulwicks/1753350803/sizes/o/
Boilerplate

30. http://www.flickr.com/photos/paulwicks/1753350803/sizes/o/
Boilerplate

31. http://www.flickr.com/photos/whoshotya/1014730135/
Domain Specific
Language

32. http://www.flickr.com/photos/whoshotya/1014730135/
Domain Specific
Language
How can it help?

33. http://www.flickr.com/photos/whoshotya/1014730135/
Domain Specific
Language
How can it help?
How do I write
one?

34. http://www.flickr.com/photos/whoshotya/1014730135/
Domain Specific
Language
How can it help?
How do I write
one?
Scala

35. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

36. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

37. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

38. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))

40. Applying the builder
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/")
val r1 = httpClient(rb.withMethod(GET).toRequest)
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson).toRequest)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id)
.toRequest)
val r4 = httpClient(rb.withMethod(GET).toRequest)
val r5 = httpClient(rb.withMethod(DELETE).addPath(id)
.toRequest)
val r6 = httpClient(rb.withMethod(GET).toRequest)

41. Applying the builder
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/")
val r1 = httpClient(rb.withMethod(GET).toRequest)
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson).toRequest)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id)
.toRequest)
val r4 = httpClient(rb.withMethod(GET).toRequest)
val r5 = httpClient(rb.withMethod(DELETE).addPath(id)
.toRequest)
val r6 = httpClient(rb.withMethod(GET).toRequest)

42. Applying the builder
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/")
val r1 = httpClient(rb.withMethod(GET).toRequest)
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson).toRequest)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id)
.toRequest)
val r4 = httpClient(rb.withMethod(GET).toRequest)
val r5 = httpClient(rb.withMethod(DELETE).addPath(id)
.toRequest)
val r6 = httpClient(rb.withMethod(GET).toRequest)

43. Applying the builder
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/")
val r1 = httpClient(rb.withMethod(GET).toRequest)
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson).toRequest)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id)
.toRequest)
val r4 = httpClient(rb.withMethod(GET).toRequest)
val r5 = httpClient(rb.withMethod(DELETE).addPath(id)
.toRequest)
val r6 = httpClient(rb.withMethod(GET).toRequest)

44. Implicit Conversion
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/")
val r1 = httpClient(rb.withMethod(GET).toRequest)
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson).toRequest)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id)
.toRequest)
val r4 = httpClient(rb.withMethod(GET).toRequest)
val r5 = httpClient(rb.withMethod(DELETE).addPath(id)
.toRequest)
val r6 = httpClient(rb.withMethod(GET).toRequest)
implicit def toRequest(b: RequestBuilder): Request =
b.toRequest

45. Implicit Conversion
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/"
val r1 = httpClient(rb.withMethod(GET))
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id))
val r4 = httpClient(rb.withMethod(GET))
val r5 = httpClient(rb.withMethod(DELETE).addPath(id))
val r6 = httpClient(rb.withMethod(GET))
implicit def toRequest(b: RequestBuilder): Request =
b.toRequest

46. Implicit Conversion
val personJson = """{ "name": "Jason" }"""
val rb = RequestBuilder()
.withUrl("http://api.rest.org/person/")
val r1 = httpClient(rb.withMethod(GET))
val r2 = httpClient(rb.withMethod(POST)
.withBody(personJson))
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(rb.withMethod(GET).addPath(id))
val r4 = httpClient(rb.withMethod(GET))
val r5 = httpClient(rb.withMethod(DELETE).addPath(id))
val r6 = httpClient(rb.withMethod(GET))

47. Nice, but show
me some DSL

48. Narrate your code
• Get from url http://api.rest.org/person/
• Post personJson to url http://api.rest.org/person/
• Get from url http://api.rest.org/person/personId
• Delete from url http://api.rest.org/person/personId

49. Narrate your code
• Get from url http://api.rest.org/person/
• Post personJson to url http://api.rest.org/person/
• Get from url http://api.rest.org/person/personId
• Delete from url http://api.rest.org/person/personId

50. Bootstapping the DSL
httpClient(RequestBuilder()
.withMethod(GET)
.withUrl("http://api.rest.org/person/"))

51. Bootstapping the DSL
httpClient(RequestBuilder()
.withMethod(GET)
.withUrl("http://api.rest.org/person/"))

52. Bootstapping the DSL
httpClient(RequestBuilder()
.withMethod(GET)
.withUrl("http://api.rest.org/person/"))
implicit def methodToRequestBuilder(method: Method):
RequestBuilder = RequestBuilder().withMethod(method)

53. Bootstapping the DSL
httpClient(GET.withUrl("http://api.rest.org/person/"))
implicit def methodToRequestBuilder(method: Method):
RequestBuilder = RequestBuilder().withMethod(method)

54. Bootstapping the DSL
httpClient(GET.withUrl("http://api.rest.org/person/"))
implicit def methodToRequestBuilder(method: Method):
RequestBuilder = RequestBuilder().withMethod(method)
methodToRequestBuilder(GET)
.withUrl("http://api.rest.org/person/")

55. Bootstapping the DSL
httpClient(GET.withUrl("http://api.rest.org/person/"))
implicit def methodToRequestBuilder(method: Method):
RequestBuilder = RequestBuilder().withMethod(method)

56. Bootstapping the DSL
httpClient(GET withUrl "http://api.rest.org/person/")

57. Initial DSL
val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(
GET withUrl "http://api.rest.org/person/")
val r2 = httpClient(
POST withUrl "http://api.rest.org/person/"
withBody personJson)
val id = r2.headers.get("X-Person-Id").get.head
val r3 = httpClient(
GET withUrl "http://api.rest.org/person/" addPath id)
val r4 = httpClient(
GET withUrl "http://api.rest.org/person/")
val r5 = httpClient(
DELETE withUrl "http://api.rest.org/person/" addPath id)
val r6 = httpClient(
GET withUrl "http://api.rest.org/person/")

58. Initial DSL
val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(
GET withUrl "http://api.rest.org/person/")
val r2 = httpClient(
POST withUrl "http://api.rest.org/person/"
withBody personJson)
val id = r2.headers.get("X-Person-Id").get.head
val r3 = httpClient(
GET withUrl "http://api.rest.org/person/" addPath id)
val r4 = httpClient(
GET withUrl "http://api.rest.org/person/")
val r5 = httpClient(
DELETE withUrl "http://api.rest.org/person/" addPath id)
val r6 = httpClient(
GET withUrl "http://api.rest.org/person/")

59. Initial DSL
val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(GET withUrl "http://api.rest.org/person/")
val r2 = httpClient(POST withUrl "http://api.rest.org/person/"
withBody personJson)
val id = r2.headers.get("X-Person-Id").get.head
val r3 = httpClient(GET withUrl "http://api.rest.org/person/" addPath id)
val r4 = httpClient(GET withUrl "http://api.rest.org/person/")
val r5 = httpClient(DELETE withUrl "http://api.rest.org/person/"
addPath id)
implicit class RichRequestBuilder(builder: RequestBuilder) {
def execute()(implicit httpClient: HttpClient): Response = {
httpClient(builder)
}
}

60. Initial DSL
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
val r1 = GET withUrl "http://api.rest.org/person/" execute ()
val r2 = POST withUrl "http://api.rest.org/person/" withBody personJson
execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET withUrl "http://api.rest.org/person/" addPath id execute ()
val r4 = GET withUrl "http://api.rest.org/person/" execute ()
val r5 = DELETE withUrl "http://api.rest.org/person/" addPath id execute ()
val r6 = GET withUrl "http://api.rest.org/person/" execute ()
implicit class RichRequestBuilder(builder: RequestBuilder) {
def execute()(implicit httpClient: HttpClient): Response = {
httpClient(builder)
}
}

61. Initial DSL
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
val r1 = GET withUrl "http://api.rest.org/person/" execute ()
val r2 = POST withUrl "http://api.rest.org/person/" withBody personJson
execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET withUrl "http://api.rest.org/person/" addPath id execute ()
val r4 = GET withUrl "http://api.rest.org/person/" execute ()
val r5 = DELETE withUrl "http://api.rest.org/person/" addPath id execute ()
val r6 = GET withUrl "http://api.rest.org/person/" execute ()
implicit class RichRequestBuilder(builder: RequestBuilder) {
def execute()(implicit httpClient: HttpClient): Response = {
httpClient(builder)
}
}

62. Initial DSL
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
val r1 = GET withUrl "http://api.rest.org/person/" execute ()
val r2 = POST withUrl "http://api.rest.org/person/" withBody personJson
execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET withUrl "http://api.rest.org/person/" addPath id execute ()
val r4 = GET withUrl "http://api.rest.org/person/" execute ()
val r5 = DELETE withUrl "http://api.rest.org/person/" addPath id execute ()
val r6 = GET withUrl "http://api.rest.org/person/" execute ()
implicit class RichRequestBuilder(builder: RequestBuilder) {
def execute()(implicit httpClient: HttpClient): Response = {
httpClient(builder)
}
}

63. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }""”
val r1 = GET withUrl "http://api.rest.org/person/" execute ()
val r2 = POST withUrl "http://api.rest.org/person/" withBody personJson
execute ()
val id = r2.headers.get("X-Person-Id”)
val r3 = GET withUrl "http://api.rest.org/person/" addPath id execute ()
val r4 = GET withUrl "http://api.rest.org/person/" execute ()
val r5 = DELETE withUrl "http://api.rest.org/person/" addPath id execute ()
val r6 = GET withUrl "http://api.rest.org/person/" execute ()

64. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
val r1 = GET withUrl "http://api.rest.org/person/" execute ()
val r2 = POST withUrl "http://api.rest.org/person/" withBody personJson
execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET withUrl "http://api.rest.org/person/" addPath id execute ()
val r4 = GET withUrl "http://api.rest.org/person/" execute ()
val r5 = DELETE withUrl "http://api.rest.org/person/" addPath id execute ()
val r6 = GET withUrl "http://api.rest.org/person/" execute ()
implicit def methodToRequestBuilder(m: Method): RequestBuilder
= RequestBuilder().withMethod(m)

65. Common Configuration
implicit val httpClient = ...
implicit val rb = RequestBuilder() withUrl "http://api.rest.org/person/"
val personJson = """{ "name": "Jason" }"""
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
implicit def methodToRequestBuilder(m: Method)
(implicit builder: RequestBuilder): RequestBuilder
= builder.withMethod(m)

66. Common Configuration
implicit val httpClient = ...
implicit val rb = RequestBuilder() withUrl "http://api.rest.org/person/"
val personJson = """{ "name": "Jason" }"""
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()

67. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ withUrl "http://api.rest.org/person") { implicit rb =>
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
}

68. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ withUrl "http://api.rest.org/person") { implicit rb =>
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
}
def using(config: RequestBuilder => RequestBuilder)
(process: RequestBuilder => Unit)
(implicit builder: RequestBuilder): Unit = {
process(config(builder))
}

69. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ withUrl "http://api.rest.org/person") { implicit rb =>
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
}
def using(config: RequestBuilder => RequestBuilder)
(process: RequestBuilder => Unit)
(implicit builder: RequestBuilder): Unit = {
process(config(builder))
}

70. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ withUrl "http://api.rest.org/person") { implicit rb =>
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
}
def using(config: RequestBuilder => RequestBuilder)
(process: RequestBuilder => Unit)
(implicit builder: RequestBuilder): Unit = {
process(config(builder))
}

71. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ withUrl "http://api.rest.org/person") { implicit rb =>
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
}
def using(config: RequestBuilder => RequestBuilder)
(process: RequestBuilder => Unit)
(implicit builder: RequestBuilder): Unit = {
process(config(builder))
}

72. Common Configuration
object RequestBuilder {
implicit val emptyBuilder = RequestBuilder(
None, None, Seq(), Seq(), None)
}

73. Common Configuration
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ withUrl "http://api.rest.org/person") { implicit rb =>
val r1 = GET execute ()
val r2 = POST withBody personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET addPath id execute ()
val r4 = GET execute ()
val r5 = DELETE addPath id execute ()
val r6 = GET execute ()
}

74. A spoonful of sugar

75. A Spoonful of sugar
implicit class RichRequestBuilder(b: RequestBuilder) {
def url(u: String) = b.withUrl(u)
def body(b: String) = b.withBody(b)
def /(p: Any) = b.addPath(p.toString)
def :?(params: (Symbol, Any)*) =
b.addQuery(params map (
p => (p._1.name, p._2.toString)): _*)
// ...
}

76. A Spoonful of sugar
implicit class RichRequestBuilder(b: RequestBuilder) {
def url(u: String) = b.withUrl(u)
def body(b: String) = b.withBody(b)
def /(p: Any) = b.addPath(p.toString)
def :?(params: (Symbol, Any)*) =
b.addQuery(params map (
p => (p._1.name, p._2.toString)): _*)
// ...
}

77. A Spoonful of sugar
implicit class RichRequestBuilder(b: RequestBuilder) {
def url(u: String) = b.withUrl(u)
def body(b: String) = b.withBody(b)
def /(p: Any) = b.addPath(p.toString)
def :?(params: (Symbol, Any)*) =
b.addQuery(params map (
p => (p._1.name, p._2.toString)): _*)
// ...
}

78. A Spoonful of sugar
implicit class RichRequestBuilder(b: RequestBuilder) {
def url(u: String) = b.withUrl(u)
def body(b: String) = b.withBody(b)
def /(p: Any) = b.addPath(p.toString)
def :?(params: (Symbol, Any)*) =
b.addQuery(params map (
p => (p._1.name, p._2.toString)): _*)
// ...
}

79. A Spoonful of sugar
implicit val httpClient = ...
val personJson = """{ "name": "Jason" }"""
using(_ url "http://api.rest.org") { implicit rb =>
val r1 = GET / "person" execute ()
val r2 = POST / "person" body personJson execute ()
val id = r2.headers.get("X-Person-Id").get.head
val r3 = GET / "person" / id execute ()
val r4 = GET / "person" execute ()
val r5 = DELETE / "person" / id execute ()
val r6 = GET / "person" :? ('page -> 2, 'per_page -> 100)
execute ()
}

80. Extracting values
val r1 = GET url "http://api.rest.org/person/" execute ()
val code1 = r1.statusCode
val list1 = jsonToList[Person](Json.parse(r1.body), JsPath)

81. Extracting values
val r1 = GET url "http://api.rest.org/person/" execute ()
val code1 = r1.statusCode
val list1 = jsonToList[Person](Json.parse(r1.body), JsPath)
Get from url http://api.rest.org/person/ returning the
status code and the body as list of persons

82. Extracting values
val r1 = GET url "http://api.rest.org/person" execute ()
val code1 = r1.statusCode
val list1 = jsonToValue[Person](Json.parse(r1.body), JsPath)
val code1 = GET url "http://api.rest.org/person"
returning (StatusCode)

83. Extracting values
val r1 = GET url "http://api.rest.org/person" execute ()
val code1 = r1.statusCode
val list1 = jsonToValue[Person](Json.parse(r1.body), JsPath)
val (code1, list1) = GET url "http://api.rest.org/person"
returning (StatusCode, BodyAsPersonList)

84. Extractors

85. Extracting values
trait ExtractorLike[+A] {
def name: String
def value(res: Response): Try[A]
def unapply(res: Response): Option[A] =
value(res).toOption
}

86. Extracting values
trait ExtractorLike[+A] {
def name: String
def value(res: Response): Try[A]
def unapply(res: Response): Option[A] =
value(res).toOption
}

87. Extracting values
trait ExtractorLike[+A] {
def name: String
def value(res: Response): Try[A]
def unapply(res: Response): Option[A] =
value(res).toOption
}

88. Extracting values
trait ExtractorLike[+A] {
def name: String
def value(res: Response): Try[A]
def unapply(res: Response): Option[A] =
value(res).toOption
}

89. Extracting values
case class Extractor[+A](name: String, op: Response => A)
extends ExtractorLike[A] {
override def value(implicit res: Response): Try[A] = {
Try { op(res) } recoverWith {
case e =>
Failure[A](new ExtractorFailedException(
s"Cannot extract $name from Response: $e",
e))
}
}
def andThen[B](nextOp: A => B): Extractor[B] =
copy(name = name + ".andThen ?", op = op andThen nextOp)
def as(newName: String) = copy(name = newName)
}

90. Extracting values
case class Extractor[+A](name: String, op: Response => A)
extends ExtractorLike[A] {
override def value(implicit res: Response): Try[A] = {
Try { op(res) } recoverWith {
case e =>
Failure[A](new ExtractorFailedException(
s"Cannot extract $name from Response: $e",
e))
}
}
def andThen[B](nextOp: A => B): Extractor[B] =
copy(name = name + ".andThen ?", op = op andThen nextOp)
def as(newName: String) = copy(name = newName)
}

91. Extracting values
case class Extractor[+A](name: String, op: Response => A)
extends ExtractorLike[A] {
override def value(implicit res: Response): Try[A] = {
Try { op(res) } recoverWith {
case e =>
Failure[A](new ExtractorFailedException(
s"Cannot extract $name from Response: $e",
e))
}
}
def andThen[B](nextOp: A => B): Extractor[B] =
copy(name = name + ".andThen ?", op = op andThen nextOp)
def as(newName: String) = copy(name = newName)
}

92. Extracting values
case class Extractor[+A](name: String, op: Response => A)
extends ExtractorLike[A] {
override def value(implicit res: Response): Try[A] = {
Try { op(res) } recoverWith {
case e =>
Failure[A](new ExtractorFailedException(
s"Cannot extract $name from Response: $e",
e))
}
}
def andThen[B](nextOp: A => B): Extractor[B] =
copy(name = name + ".andThen ?", op = op andThen nextOp)
def as(newName: String) = copy(name = newName)
}

93. Extracting values
val StatusCode = Extractor[Int](
"StatusCode", r => r.statusCode)

94. Extracting values
val StatusCode = Extractor[Int](
"StatusCode", r => r.statusCode)
val BodyText = Extractor[String](
"BodyText", r => r.body.get)

95. Extracting values
val StatusCode = Extractor[Int](
"StatusCode", r => r.statusCode)
val BodyText = Extractor[String](
"BodyText", r => r.body.get)
def header(name: String) = {
Extractor[String](s"header($name)",
r => r.headers(name).mkString(", "))
}

96. Extractors Compose
val JsonBody = BodyText andThen Json.parse as "JsonBody"

97. Extractors Compose
val JsonBody = BodyText andThen Json.parse as "JsonBody"
def jsonBodyAs[T : Reads : ClassTag](path: JsPath): Extractor[T] = {
val tag = implicitly[ClassTag[T]]
JsonBody andThen (jsonToValue(_, path)) as
(s"jsonBodyAs[${tag.runtimeClass.getSimpleName}]")
}

98. Extractors Compose
val JsonBody = BodyText andThen Json.parse as "JsonBody"
def jsonBodyAs[T : Reads : ClassTag](path: JsPath): Extractor[T] = {
val tag = implicitly[ClassTag[T]]
JsonBody andThen (jsonToValue(_, path)) as
(s"jsonBodyAs[${tag.runtimeClass.getSimpleName}]")
}
def jsonBodyAs[T : Reads : ClassTag]: Extractor[T] =
jsonBodyAs(JsPath)

99. Extractors Compose
val JsonBody = BodyText andThen Json.parse as "JsonBody”
def jsonBodyAs[T : Reads : ClassTag](path: JsPath): Extractor[T] = {
val tag = implicitly[ClassTag[T]]
JsonBody andThen (jsonToValue(_, path)) as
(s"jsonBodyAs[${tag.runtimeClass.getSimpleName}]")
}
def jsonBodyAs[T : Reads : ClassTag]: Extractor[T] =
jsonBodyAs(JsPath)
val BodyAsPerson = jsonBodyAs[Person]
val BodyAsName = jsonBodyAs[String](__ "name")

100. Extracting values
implicit class RichRequestBuilder(builder: RequestBuilder) {
// ...
def returning[T1](ext1: Extractor[T1])
(implicit httpClient: HttpClient): T1 = {
val res = execute()
ext1.value(res)
}
def returning[T1, T2](ext1: Extractor[T1], ext1: Extractor[T2])
(implicit httpClient: HttpClient): (T1, T2) = {
val res = execute()
(ext1.value(res), ext2.value(res))
}
}

101. Extracting values
implicit class RichRequestBuilder(builder: RequestBuilder) {
// ...
def returning[T1](ext1: Extractor[T1])
(implicit httpClient: HttpClient): T1 = {
val res = execute()
ext1.value(res)
}
def returning[T1, T2](ext1: Extractor[T1], ext2: Extractor[T2])
(implicit httpClient: HttpClient): (T1, T2) = {
val res = execute()
(ext1.value(res), ext2.value(res))
}
}

102. Extracting values
implicit class RichRequestBuilder(builder: RequestBuilder) {
// ...
def returning[T1](ext1: Extractor[T1])
(implicit httpClient: HttpClient): T1 = {
val res = execute()
ext1.value(res)
}
def returning[T1, T2](ext1: Extractor[T1], ext2: Extractor[T2])
(implicit httpClient: HttpClient): (T1, T2) = {
val res = execute()
(ext1.value(res), ext2.value(res))
}
}

103. Extracting values
using(_ url "http://api.rest.org") { implicit rb =>
val (code1, list1) = GET / "person" returning
(StatusCode, BodyAsPersonList)
val (code2, id) = POST / "person" body personJson
returning (StatusCode, header("X-Person-Id”)
val (code3, person) = GET / "person" / id returning
(StatusCode, BodyAsPerson)
val (code4, list2) = GET / "person" returning
(StatusCode, BodyAsPersonList)
val code5 = DELETE / "person" / id returning StatusCode
val (code6, list3) = GET / "person" returning
(StatusCode, BodyAsPersonList)
}

104. Asserting values
val (code1, list1) = GET / "person" returning (
StatusCode, BodyAsPersonList)
assert (code1 === Status.OK)
assert (list1 === EmptyList)

105. Asserting values
val (code1, list1) = GET / "person" returning (
StatusCode, BodyAsPersonList)
assert (code1 === Status.OK)
assert (list1 === EmptyList)
Get from url http://api.rest.org/person/ asserting the
status code is OK and and the body is an empty list of
persons

106. Asserting values
val (code1, list1) = GET / "person" returning (
StatusCode, BodyAsPersonList)
assert (code1 === Status.OK)
assert (list1 === EmptyList)
GET / "person" asserting (
StatusCode === Status.OK,
BodyAsPersonList === EmptyList)

107. Assertions

108. Asserting values
GET / "person" asserting (
StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
type Assertion = Response => Option[String]

109. Asserting values
implicit class RichExtractor[A](ext: ExtractorLike[A]) {
def ===[B >: A](expected: B): Assertion = { res =>
val maybeValue = ext.value(res)
maybeValue match {
case Success(value) if (value == expected) =>
None
case Success(value) =>
Some(s"${ext.name}: $value != $expected")
case Failure(e) =>
Some(e.getMessage)
}
}
}

110. Asserting values
implicit class RichExtractor[A](ext: ExtractorLike[A]) {
def ===[B >: A](expected: B): Assertion = ???
def !==[B >: A](expected: B): Assertion = ???
def < [B >: A](expected: B)
(implicit ord: math.Ordering[B]): Assertion = ???
def <=[B >: A](expected: B)
(implicit ord: math.Ordering[B]): Assertion = ???
def > [B >: A](expected: B)
(implicit ord: math.Ordering[B]): Assertion = ???
def >=[B >: A](expected: B)
(implicit ord: math.Ordering[B]): Assertion = ???
}

111. Asserting values
implicit class RichRequestBuilder(builder: RequestBuilder) {
def asserting(assertions: Assertion*)
(implicit client: HttpClient): Response = {
val response = execute()
val failures = for {
assertion <- assertions
failureMessage <- assertion(response)
} yield failureMessage
if (failures.nonEmpty) {
throw assertionFailed(failures)
}
response
}
}

112. Asserting values
using(_ url "http://api.rest.org") { implicit rb =>
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
val id = POST / "person" body personJson
asserting (StatusCode === Status.Created)
returning (header("X-Person-Id"))
GET / "person" / id asserting (StatusCode === Status.OK,
BodyAsPerson === Jason)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === Seq(Jason))
DELETE / "person" / id asserting (StatusCode === Status.OK)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
}

113. http://www.flickr.com/photos/ajkohn2001/2532935194/
Wow I can read it!

114. Asserting values
using(_ url "http://api.rest.org") { implicit rb =>
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
val id = POST / "person" body personJson
asserting (StatusCode === Status.Created)
returning (header("X-Person-Id"))
GET / "person" / id asserting (StatusCode === Status.OK,
BodyAsPerson === Jason)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === Seq(Jason))
DELETE / "person" / id asserting (StatusCode === Status.OK)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
}

115. RTFM? Wheres TFM?
http://wallpaperscraft.com/download/dog_boxer_laptop_lie_face_52801/

116. Codebase Structure
API
DSL

117. Codebase Structure
API
DSL
Extractors

118. Codebase Structure
API
DSL
Extractors
Json
Extractors
Xml
Extractors

119. Codebase Structure
API
DSL
Extractors
Json
Extractors
Xml
Extractors
Extended
DSL
Extended
Extractors

120. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r1.statusCode === Status.OK)
r1.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
assert(r2.statusCode === Status.Created)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r3.statusCode === Status.OK)
r3.body match {
Some(body) =>
assert(jsonAs[Person](body) === Jason)
None => fail("Expected a body"))
}
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r4.statusCode === Status.OK)
r4.body match {
Some(body) =>
assert(jsonAsList[Person](body) === Seq(Jason))
None => fail("Expected a body"))
}
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r5.statusCode === Status.OK)
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r6.statusCode === Status.OK)
r6.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}
using(_ url "http://api.rest.org") { implicit rb =>
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
val id = POST / "person" body personJson
asserting (StatusCode === Status.Created)
returning (header("X-Person-Id"))
GET / "person" / id asserting (StatusCode === Status.OK,
BodyAsPersonList === Jason)
GET asserting (StatusCode === Status.OK,
BodyAsPersonList === Seq(Jason))
DELETE / "person" / id asserting (StatusCode === Status.OK)
GET / id asserting (StatusCode === Status.NotFound)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
}
BoilerplateTest
DSLTest

121. val personJson = """{ "name": "Jason" }"""
val r1 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r1.statusCode === Status.OK)
r1.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}
val r2 = httpClient(Request(
POST, new URI("http://api.rest.org/person/"),
Map(), Some(personJson)))
assert(r2.statusCode === Status.Created)
val id = r2.headers("X-Person-Id").head
val r3 = httpClient(Request(
GET, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r3.statusCode === Status.OK)
r3.body match {
Some(body) =>
assert(jsonAs[Person](body) === Jason)
None => fail("Expected a body"))
}
val r4 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r4.statusCode === Status.OK)
r4.body match {
Some(body) =>
assert(jsonAsList[Person](body) === Seq(Jason))
None => fail("Expected a body"))
}
val r5 = httpClient(Request(
DELETE, new URI("http://api.rest.org/person/" + id),
Map(), None))
assert(r5.statusCode === Status.OK)
val r6 = httpClient(Request(
GET, new URI("http://api.rest.org/person/"),
Map(), None))
assert(r6.statusCode === Status.OK)
r6.body match {
Some(body) =>
assert(jsonAsList[Person](body) === EmptyList)
None => fail("Expected a body"))
}
using(_ url "http://api.rest.org") { implicit rb =>
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
val id = POST / "person" body personJson
asserting (StatusCode === Status.Created)
returning (header("X-Person-Id"))
GET / "person" / id asserting (StatusCode === Status.OK,
BodyAsPersonList === Jason)
GET asserting (StatusCode === Status.OK,
BodyAsPersonList === Seq(Jason))
DELETE / "person" / id asserting (StatusCode === Status.OK)
GET / id asserting (StatusCode === Status.NotFound)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
}
object Extractors {
trait ExtractorLike[+A] {
def name: String
def value(implicit res: Response): Try[A]
def unapply(res: Response): Option[A] = value(res).toOption
}
case class Extractor[+A](name: String, op: Response => A) extends ExtractorLike[A] {
override def value(implicit res: Response): Try[A] = {
Try { op(res) } recoverWith {
case e =>
Failure[A](new ExtractorFailedException(s"Cannot extract $name from Response: $e",e))
}
}
def andThen[B](nextOp: A => B): Extractor[B] = copy(name = name + ".andThen ?", op = op andThen nextOp)
def as(newName: String) = copy(name = newName)
}
val StatusCode = Extractor[Int]("StatusCode", r => r.statusCode)
val BodyText = Extractor[String]("BodyText", r => r.body.get)
def header(name: String) = {
Extractor[String](s"header($name)", r => r.headers(name).mkString(", "))
}
val JsonBody = BodyText andThen Json.parse as "JsonBody"
def jsonBodyAs[T : Reads : ClassTag](path: JsPath): Extractor[T] = {
val tag = implicitly[ClassTag[T]]
JsonBody andThen (jsonToValue(_, path)) as (s"jsonBodyAs[${tag.runtimeClass.getSimpleName}]")
}
def jsonBodyAs[T : Reads : ClassTag]: Extractor[T] = jsonBodyAs(JsPath)
val BodyAsPerson = jsonBodyAs[Person]
}
trait Dsl extends Api with Extractors {
implicit def toRequest(b: RequestBuilder): Request = b.toRequest
implicit def methodToRequestBuilder(m: Method)(implicit builder: RequestBuilder): RequestBuilder = builder.withMethod(m)
def using(config: RequestBuilder => RequestBuilder)(process: RequestBuilder => Unit)(implicit builder: RequestBuilder): Unit = {
process(config(builder))
}
type Assertion = Response => Option[String]
implicit class RichRequestBuilder(builder: RequestBuilder) {
def url(u: String) = b.withUrl(u)
def body(b: String) = b.withBody(b)
def /(p: Any) = b.addPath(p.toString)
def :?(params: (Symbol, Any)*) = b.addQuery(params map (p => (p._1.name, p._2.toString)): _*)
def execute()(implicit httpClient: HttpClient): Response = {
httpClient(builder)
}
def returning[T1](ext1: Extractor[T1])(implicit httpClient: HttpClient): T1 = {
val res = execute()
ext1.value(res)
}
def returning[T1, T2](ext1: Extractor[T1], ext1: Extractor[T2])(implicit httpClient: HttpClient): (T1, T2) = {
val res = execute()
(ext1.value(res), ext2.value(res))
}
def asserting(assertions: Assertion*)(implicit client: HttpClient): Response = {
val response = execute()
val assertionFailures = for {
assertion <- assertions
failureMessage <- assertion(response)
} yield failureMessage
if (assertionFailures.nonEmpty) {
throw assertionFailed(assertionFailures)
}
response
}
}
implicit class RichExtractor[A](ext: ExtractorLike[A]) {
def ===[B >: A](expected: B): Assertion = { res =>
val maybeValue = ext.value(res)
maybeValue match {
case Success(value) if (value == expected) =>
None
case Success(value) =>
Some(s"${ext.name}: $value != $expected")
case Failure(e) =>
Some(e.getMessage)
}
}
def !==[B >: A](expected: B): Assertion = ???
def < [B >: A](expected: B)(implicit ord: math.Ordering[B]): Assertion = ???
def <=[B >: A](expected: B)(implicit ord: math.Ordering[B]): Assertion = ???
def > [B >: A](expected: B)(implicit ord: math.Ordering[B]): Assertion = ???
def >=[B >: A](expected: B)(implicit ord: math.Ordering[B]): Assertion = ???
}
}
BoilerplateTestDslTest
DSLImplementation

122. http://en.wikipedia.org/wiki/Optical_communication

123. Code is Communication
using(_ url "http://api.rest.org") { implicit rb =>
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
val id = POST / "person" body personJson
asserting (StatusCode === Status.Created)
returning (header("X-Person-Id"))
GET / "person" / id asserting (StatusCode === Status.OK,
BodyAsPersonList === Jason)
GET asserting (StatusCode === Status.OK,
BodyAsPersonList === Seq(Jason))
DELETE / "person" / id asserting (StatusCode === Status.OK)
GET / "person" asserting (StatusCode === Status.OK,
BodyAsPersonList === EmptyList)
}

124. DSL Resources - Books
DSLs in Action
By Debasish Ghosh
ISBN: 9781935182450
http://www.manning.com/ghosh/
Scala in Depth
By Joshua D. Suereth
ISBN: 9781935182702
http://www.manning.com/suereth/

125. DSL Resources – Projects

127. http://www.flickr.com/photos/bilal-kamoon/6835060992/sizes/o/

128. Thank You!!!
Iain Hull
Email: iain.hull@workday.com
Twitter: @IainHull
Web: http://IainHull.github.io
Workday