Andy Bennett, Founder, Knodium This talk looks at how to make an HTTP API available as a self-contained procedure or function, just like any other library or API code that you might be used to using or importing into your programs. Whether you're implementing an SDK for your own API or just trying to bind to an adhoc API that you want to use, this talk will cover how to do it in an elegant and simple way without lots of adhoc code duplication, needless boilerplate or irrelevant detail.

1. andyjpb@knodium.com
@databasescaling
Thursday, 25th September 2014
2014/09/24 APIconUK 2014 1 / 149

2. HTTP APIs As First Class Procedures
a@kno.dm
@databasescaling
Thursday, 25th September 2014
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3. HTTP APIs As First Class Procedures
Cutting out SDK Complexity
a@kno.dm
@databasescaling
Thursday, 25th September 2014
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4. andyjpb
http://www.obsoletecomputermuseum.org/oliv_m24/m24.jpg
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5. GSM AT Command Set
cmd AT+CREG "Network Registration (ver.2)"
set AT+CREG=[<creg_stat>],<creg_urc>,<ci>
read AT+CREG?
+CREG:<creg_urc>,<creg_stat>[,<lac>,<ci>]
test AT+CREG=?
+CREG
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6. GSM AT Command Set
cmd AT+CREG "Network Registration (ver.2)"
set AT+CREG=[<creg_stat>],<creg_urc>,<ci>
read AT+CREG?
+CREG:<creg_urc>,<creg_stat>[,<lac>,<ci>]
test AT+CREG=?
+CREG
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7. GSM AT Command Set
cmd AT+CREG "Network Registration (ver.2)"
set AT+CREG=[<creg_stat>],<creg_urc>,<ci>
read AT+CREG?
+CREG:<creg_urc>,<creg_stat>[,<lac>,<ci>]
test AT+CREG=?
+CREG
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8. GSM AT Command Set
cmd AT+CREG "Network Registration (ver.2)"
set AT+CREG=[<creg_stat>],<creg_urc>,<ci>
read AT+CREG?
+CREG:<creg_urc>,<creg_stat>[,<lac>,<ci>]
test AT+CREG=?
+CREG
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9. GSM AT Command Set
cmd AT+CREG "Network Registration (ver.2)"
set AT+CREG=[<creg_stat>],<creg_urc>,<ci>
read AT+CREG?
+CREG:<creg_urc>,<creg_stat>[,<lac>,<ci>]
test AT+CREG=?
+CREG
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10. GSM AT Command Set
cmd AT+CREG "Network Registration (ver.2)"
set AT+CREG=[<creg_stat>],<creg_urc>,<ci>
read AT+CREG?
+CREG:<creg_urc>,<creg_stat>[,<lac>,<ci>]
test AT+CREG=?
+CREG
int AT_CREG_test(int port, struct AT_result* result) {
int r = 0;
if ((r = sendcmd(port, "AT+CREG=?", result))) return r;
return recvresp(port, result);
}
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11. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result) {
/* Increment the cursor to the next row in the direction
* that the cursor is travelling and return the row to
* the caller.
*/
...
}
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12. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result);
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13. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result);
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14. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result);
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15. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result) {
DBrow *(*original_proc)(DB*, DBcursor*, DBresult*);
DBrow *original_result;
log(“Entering CursorNext”);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
original_proc = dlsym(RTLD_NEXT, “CursorNext”);
original_result = (*original_proc)(env, cursor, result);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
Log(“Leaving CursorNext”);
return (original_result);
}
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16. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result) {
DBrow *(*original_proc)(DB*, DBcursor*, DBresult*);
DBrow *original_result;
log(“Entering CursorNext”);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
original_proc = dlsym(RTLD_NEXT, “CursorNext”);
original_result = (*original_proc)(env, cursor, result);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
Log(“Leaving CursorNext”);
return (original_result);
}
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17. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result) {
DBrow *(*original_proc)(DB*, DBcursor*, DBresult*);
DBrow *original_result;
log(“Entering CursorNext”);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
original_proc = dlsym(RTLD_NEXT, “CursorNext”);
original_result = (*original_proc)(env, cursor, result);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
Log(“Leaving CursorNext”);
return (original_result);
}
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18. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result) {
DBrow *(*original_proc)(DB*, DBcursor*, DBresult*);
DBrow *original_result;
log(“Entering CursorNext”);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
original_proc = dlsym(RTLD_NEXT, “CursorNext”);
original_result = (*original_proc)(env, cursor, result);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
Log(“Leaving CursorNext”);
return (original_result);
}
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19. Execution Tracing
DBrow *CursorNext(DB *env, DBcursor* cursor, DBresult* result) {
DBrow *(*original_proc)(DB*, DBcursor*, DBresult*);
DBrow *original_result;
log(“Entering CursorNext”);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
original_proc = dlsym(RTLD_NEXT, “CursorNext”);
original_result = (*original_proc)(env, cursor, result);
DB_serialise(env);
Cursor_serialise(cursor);
Result_serialise(result);
Log(“Leaving CursorNext”);
return (original_result);
}
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20. Knodium
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21. Knodium
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22. Knodium
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23. Knodium
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24. Knodium
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25. Knodium
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26. Knodium
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27. Knodium
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28. Knodium
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29. Knodium
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30. Knodium
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31. Knodium
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32. Knodium
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33. Knodium
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34. Knodium
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35. Knodium
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36. Knodium
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37. Knodium
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38. Knodium
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39. Knodium
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40. Knodium
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41. Knodium
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42. Scheme
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43. REST
Read the HTTP spec!
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44. REST
"Finally, I describe the lessons
learned from applying REST to the
design of the Hypertext Transfer
Protocol and Uniform Resource
Identifier standards, and from their
subsequent deployment in Web
client and server software."
-- Roy Fielding
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45. REST
GET
Retrieves a representation of the requested
resource (current state)
POST
Create a new instance of a resource
PUT
Update an existing instance of a resource
DELETE
Remove an existing instance of a resource
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46. http://static.squarespace.com/static/518f5d62e4b075248d6a3f90/t/51bb91f3e4b0405092e56e27/1371247103965/not-restful.jpg
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47. DCE
"The Distributed Computing
Environment (DCE) is a software
system developed in the early 1990s"
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48. DCE/RPC
"This system allows programmers to
write distributed software as if it were
all working on the same computer,
without having to worry about the
underlying network code."
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49. DCE/RPC
"This system allows programmers to
write distributed software as if it were
all working on the same computer,
without having to worry about the
underlying network code."
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50. Adhoc Binding
“I'm looking for a pretty generic,
fully featured REST client/API in
python. Not bare bones, but plush,
nice to use.”
http://stackoverflow.com/questions/4355997/is-there-a-generic-python-library-to-consume-rest-based-services
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51. Adhoc Binding
“...an HTTP resource kit for Python. It
allows you to easily access to HTTP
resource and build objects around it.”
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52. Adhoc Binding
“...an HTTP resource kit for Python. It
allows you to easily access to HTTP
resource and build objects around it.”
“[It] is a full HTTP client using pure
socket calls and its own HTTP parser.”
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53. Adhoc Binding
api = API('http://myrestful/api/v1')
# GET /resource
api.resource.get()
# GET /resource (with accept header = application/json)
api.resource.get(format='json')
# GET /resource?attr=value
api.resource.get(attr=value)
# POST /resource
api.resource.post(attr=value, attr2=value2, ...)
# GET /resource/id/resource_collection
api.resoure(id).resource_collection().get()
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54. Adhoc Binding
☺
api = API('http://myrestful/api/v1')
# GET /resource
api.resource.get()
# GET /resource (with accept header = application/json)
api.resource.get(format='json')
# GET /resource?attr=value
api.resource.get(attr=value)
# POST /resource
api.resource.post(attr=value, attr2=value2, ...)
# GET /resource/id/resource_collection
api.resoure(id).resource_collection().get()
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55. Adhoc Binding
☺
api = API('http://myrestful/api/v1')
# GET /resource
api.resource.get()
# GET /resource (with accept header = application/json)
api.resource.get(format='json')
# GET /resource?attr=value
api.resource.get(attr=value)
# POST /resource
api.resource.post(attr=value, attr2=value2, ...)
# GET /resource/id/resource_collection
api.resoure(id).resource_collection().get()
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56. Adhoc Binding
☺
api = API('http://myrestful/api/v1')
# GET /resource
api.resource.get()
☹
# GET /resource (with accept header = application/json)
api.resource.get(format='json')
# GET /resource?attr=value
api.resource.get(attr=value)
# POST /resource
☹
api.resource.post(attr=value, attr2=value2, ...)
# GET /resource/id/resource_collection
api.resoure(id).resource_collection().get()
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57. Adhoc Binding
☺
api = API('http://myrestful/api/v1')
# GET /resource
api.resource.get()
# GET /resource (with accept header = application/json)
api.resource.get(format='json')
# GET /resource?attr=value
api.resource.get(attr=value)
# POST /resource
api.resource.post(attr=value, attr2=value2, ...)
# GET /resource/id/resource_collection
api.resoure(id).resource_collection().get()
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58. Adhoc Binding
☺
api = API('http://myrestful/api/v1')
# GET /resource
api.resource.get()
# GET /resource (with accept header = application/json)
api.resource.get(format='json')
# GET /resource?attr=value
api.resource.get(attr=value)
# POST /resource
api.resource.post(attr=value, attr2=value2, ...)
# GET /resource/id/resource_collection
api.resoure(id).resource_collection().get()
☹
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59. SDKs
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60. SDKs
● HTTP Clients
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61. SDKs
● HTTP Clients
● REST Clients
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62. SDKs
● HTTP Clients
● REST Clients
● Socket Pools
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63. SDKs
● HTTP Clients
● REST Clients
● Socket Pools
● Request Builders
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64. SDKs
● HTTP Clients
● REST Clients
● Socket Pools
● Request Builders
● URI Concatenators
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65. SDKs
● HTTP Clients
● REST Clients
● Socket Pools
● Request Builders
● URI Concatenators
● OAuth Implementations
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66. SDKs
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67. SDKs
● PHP
● Python
● Ruby
● .NET
● Java
● C, C++
● Perl
● Android, iOS, Windows Mobile, Blackberry
● Javascript
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68. ctypes
https://docs.python.org/2/library/ctypes.html
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69. ctypes
>>> from ctypes import *
>>> cdll.LoadLibrary("libc.so.6")
<CDLL 'libc.so.6', handle 7f408bf8a000 at 21eb8d0>
>>> libc = CDLL("libc.so.6")
>>> my_printf = libc.printf
>>> my_printf("Hello World")
Hello World11
>>> my_printf("Hello %s", "Andy")
Hello Andy10
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70. ctypes
>>> from ctypes import *
>>> cdll.LoadLibrary("libc.so.6")
<CDLL 'libc.so.6', handle 7f408bf8a000 at 21eb8d0>
>>> libc = CDLL("libc.so.6")
>>> my_printf = libc.printf
>>> my_printf("Hello World")
Hello World11
>>> my_printf("Hello %s", "Andy")
Hello Andy10
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71. ctypes
>>> from ctypes import *
>>> cdll.LoadLibrary("libc.so.6")
<CDLL 'libc.so.6', handle 7f408bf8a000 at 21eb8d0>
>>> libc = CDLL("libc.so.6")
>>> my_printf = libc.printf
>>> my_printf("Hello World")
Hello World11
>>> my_printf("Hello %s", "Andy")
Hello Andy10
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72. ctypes
>>> from ctypes import *
>>> cdll.LoadLibrary("libc.so.6")
<CDLL 'libc.so.6', handle 7f408bf8a000 at 21eb8d0>
>>> libc = CDLL("libc.so.6")
>>> my_printf = libc.printf
>>> my_printf("Hello World")
Hello World11
>>> my_printf("Hello %s", "Andy")
Hello Andy10
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73. ctypes
● Code Loading
● Calling Conventions
● Marshalling
● Memory Models
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74. ● HTTP Implementation
● HTTP Client
● URI / URL Library
● Media Format Libraries
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75. ● HTTP Implementation
● HTTP Client
● URI / URL Library
● Media Format Libraries
● A Way To Put It All Together
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76. Calling Conventions
https://api-content.dropbox.com/1/files/auto/<path>
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77. Calling Conventions
https://api-content.dropbox.com/1/files/auto/<path>
https://example.com/price/<date>/<€>/<£>
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78. Calling Conventions
https://api-content.dropbox.com/1/files/auto/<path>
https://example.com/price/<date>/<€>/<£>
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79. Calling Conventions
files(<path>)
price(<date>, <€>, <£>)
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80. Calling Conventions
https://api.dropbox.com/1/delta?cursor=<x>
https://example.com/trades?tick=<n>
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81. Calling Conventions
delta(cursor=<x>)
trades(tick=<n>)
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82. Calling Conventions
https://.../1/revisions/auto/<path>?rev_limit=<y>
https://example.com/trades/<stock>?tick=<y>
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83. Calling Conventions
revisions(<path>, rev_limit=<y>)
trades(<stock>, tick=<y>)
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84. Calling Conventions
(define (name pos-arg-1 pos-arg-2 #!key key-arg-1)
…
result)
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85. Calling Conventions
(define (add a b)
(+ a b))
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86. Calling Conventions
(define (add a b)
(+ a b))
(add 19 47)
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87. Calling Conventions
(define (add a b)
(+ a b))
(add 19 47)
66
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88. Calling Conventions
(define (add a b)
(+ a b))
(add 19 47)
66
(define (raise n #!key power)
(expt n power))
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89. Calling Conventions
(define (add a b)
(+ a b))
(add 19 47)
66
(define (raise n #!key power)
(expt n power))
(raise 2 power: 4)
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90. Calling Conventions
(define (add a b)
(+ a b))
(add 19 47)
66
(define (raise n #!key power)
(expt n power))
(raise 2 power: 4)
16
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91. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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92. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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93. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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94. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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95. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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96. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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97. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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98. Putting It All Together
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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99. Putting It All Together
https://api.dropbox.com/1/account/info
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100. Putting It All Together
https://api.dropbox.com/1/account/info
(define-method (account/info #!key locale)
"https://api.dropbox.com/1/account/info"
#f
read-json)
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101. Putting It All Together
https://api.dropbox.com/1/account/info
(define-method (account/info #!key locale)
"https://api.dropbox.com/1/account/info"
#f
read-json)
#;> account/info
#<procedure (? #!key locale)
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102. Marshalling / Unmarshalling
https://api.dropbox.com/1/account/info
(define-method (account/info #!key locale)
"https://api.dropbox.com/1/account/info"
#f
read-json)
#;> account/info
#<procedure (? #!key locale)
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103. Marshalling / Unmarshalling
https://api.dropbox.com/1/account/info
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104. Marshalling / Unmarshalling
https://api.dropbox.com/1/account/info
{
"referral_link": "https://www.dropbox.com/referrals/r1a2n3d4m5s6t7",
"display_name": "John P. User",
"uid": 12345678,
"team": {
"name": "Acme Inc."
},
"country": "US",
"quota_info": {
"shared": 253738410565,
"quota": 107374182400000,
"normal": 680031877871
}
}
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105. Marshalling / Unmarshalling
https://api.dropbox.com/1/account/info
((referral_link . "https://www.dropbox.com/referrals/r1a2n3d4m5s6t7")
(display_name . "John P. User")
(uid . 12345678)
(country . "US")
(quota_info
(shared . 253738410565)
(quota . 107374182400000)
(normal . 680031877871)))
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106. Marshalling / Unmarshalling
(account/info)
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107. Marshalling / Unmarshalling
(account/info)
read-string
{
"referral_link": "https://www.dropbox.com/referrals/r1a2n3d4m5s6t7",
"display_name": "John P. User",
"uid": 12345678,
"team": {
"name": "Acme Inc."
},
"country": "US",
"quota_info": {
"shared": 253738410565,
"quota": 107374182400000,
"normal": 680031877871
}
}
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108. Marshalling / Unmarshalling
(account/info)
read-json
((referral_link . "https://www.dropbox.com/referrals/r1a2n3d4m5s6t7")
(display_name . "John P. User")
(uid . 12345678)
(country . "US")
(quota_info
(shared . 253738410565)
(quota . 107374182400000)
(normal . 680031877871)))
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109. Calling Conventions
https://example.com/trades/<stock>?tick=<y>
(define-method (trades stock #!key tick)
"https://examples.com/trades")
#f
read-json)
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110. Calling Conventions
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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111. Calling Conventions
(use rest-bind)
(define-method
(procedure-name path-arg... #!key query-arg...)
uri-or-request
body-writer
body-reader
#!optional
header-reader)
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112. Calling Conventions
https://example.com/trades/<stock>?tick=<y>
(define-method (trades stock #!key tick)
"https://examples.com/trades")
#f
read-json)
2014/09/24 APIconUK 2014 112 / 149

113. Calling Conventions
https://example.com/trades/<stock>?tick=<y>
(define-method (trades stock #!key tick)
"https://examples.com/trades")
#f
read-json)
2014/09/24 APIconUK 2014 113 / 149

114. Calling Conventions
https://example.com/trades/<stock>?tick=<y>
(define-method (trades stock #!key tick)
(make-request
method: 'PUT
uri: (uri-reference: "https://examples.com/trades")
#f
read-json)
2014/09/24 APIconUK 2014 114 / 149

115. Calling Conventions
https://example.com/trades/<stock>?tick=<y>
(define-method (trades stock #!key tick)
(make-request
method: 'PUT
uri: (uri-reference: "https://examples.com/trades")
headers: '(accept #(application/json ((q . 0.5)))))
#f
read-json)
2014/09/24 APIconUK 2014 115 / 149

116. Putting It All Together
(trades 'LON:TSCO tick: 3)
2014/09/24 APIconUK 2014 116 / 149

117. Putting It All Together
(trades 'LON:TSCO tick: 3)
((1411602130 . 19490
1411602133 . +6
1411602136 . +1
1411602139 . -2
1411602142 . +3
1411602145 . +1
1411602148 . -2
1411602151 . -1
1411602154 . 0
1411602157 . +1))
2014/09/24 APIconUK 2014 117 / 149

118. ● HTTP Implementation
● HTTP Client
● URI / URL Library
● Media Format Libraries
● A Way To Put It All Together
2014/09/24 APIconUK 2014 118 / 149

119. ● HTTP Implementation
● HTTP Client
● URI / URL Library
● Media Format Libraries
● A Way To Put It All Together
2014/09/24 APIconUK 2014 119 / 149

120. ● HTTP Implementation
● HTTP Client
● URI / URL Library
● Media Format Libraries
● A Way To Put It All Together
66 lines
2014/09/24 APIconUK 2014 120 / 149

121. Putting It All Together
(module dropbox-lolevel
(dropbox
make-dropbox-app
account/info
files:get
files:put
files:post
metadata
delta
revisions
restore
search
shares
media
copy-ref
thumbnails
chunked_upload
commit_chunked_upload
fileops/copy
fileops/create_folder
fileops/delete
fileops/move
callback
old-output-port)
2014/09/24 APIconUK 2014 121 / 149

122. oauth
Dropbox
2014/09/24 APIconUK 2014 122 / 149

123. oauth
Dropbox
A User
2014/09/24 APIconUK 2014 123 / 149

124. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 124 / 149

125. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 125 / 149

126. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 126 / 149

127. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 127 / 149

128. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 128 / 149

129. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 129 / 149

130. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 130 / 149

131. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 131 / 149

132. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 132 / 149

133. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 133 / 149

134. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 134 / 149

135. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 135 / 149

136. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 136 / 149

137. oauth
(use oauth-client)
(define dropbox
(make-oauth-service-provider
protocol-version: 1.0
credential-request-url: "https://api.dropbox.com/1/oauth/request_token"
owner-auth-url: "https://www.dropbox.com/1/oauth/authorize"
token-request-url: "https://api.dropbox.com/1/oauth/access_token"
signature-method: 'plaintext))
2014/09/24 APIconUK 2014 137 / 149

138. (use oauth-client)
(define dropbox-app
(make-oauth-service
oauth
service: dropbox
client-credential: (make-oauth-credential "<token>" "<secret>")))
2014/09/24 APIconUK 2014 138 / 149

139. oauth
Dropbox
A User
Knodium
2014/09/24 APIconUK 2014 139 / 149

140. Putting it all together
(with-oauth <app> <credential>
...)
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141. Putting it all together
(account/info)
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142. Putting it all together
(with-oauth <app> <credential>
(account/info))
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143. Putting it all together
(account/info)
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144. Putting it all together
(account/info)
2014/09/24 APIconUK 2014 144 / 149

145. Putting it all together
(display-name)
(account/info)
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146. Putting it all together
(web-page-logic)
(display-name)
(account/info)
2014/09/24 APIconUK 2014 146 / 149

147. Putting it all together
(request-routing)
(web-page-logic)
(display-name)
(account/info)
2014/09/24 APIconUK 2014 147 / 149

148. Putting it all together
(with-oauth <app> <credential>)
(request-routing)
(web-page-logic)
(display-name)
(account/info)
2014/09/24 APIconUK 2014 148 / 149

149. ?
2014/09/24 APIconUK 2014 149 / 149

150. 2014/09/24 APIconUK 2014 150 / 149

151. URIs & URLs Are Not Strings
https://example.com/price/<x>
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152. URIs & URLs Are Not Strings
https://example.com/price/<x>?tick=<n>
2014/09/24 APIconUK 2014 152 / 149

153. URIs & URLs Are Not Strings
https://example.com/price/<x>?tick=<n>
2014/09/24 APIconUK 2014 153 / 149

154. URIs & URLs Are Not Strings
https://example.com/price/<x>?tick=<n>
2014/09/24 APIconUK 2014 154 / 149

155. URIs & URLs Are Not Strings
https://example.com/price/<x>?tick=<n>
https://example.com/price/<x>/<y>
2014/09/24 APIconUK 2014 155 / 149

156. URIs & URLs Are Not Strings
https://example.com/price/<x>/<y>?tick=<n>
2014/09/24 APIconUK 2014 156 / 149

157. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 157 / 149

158. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 158 / 149

159. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 159 / 149

160. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 160 / 149

161. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 161 / 149

162. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 162 / 149

163. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 163 / 149

164. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
2014/09/24 APIconUK 2014 164 / 149

165. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
ftp://example.com
//example.com/resource
//example.com
/book
?length=17;width=19
?depth=21&height=29#glossary
#chapter1
2014/09/24 APIconUK 2014 165 / 149

166. URIs & URLs Are Not Strings
https://user:pass@example.com/price?tick=3#appendix
ftp://example.com
//example.com/resource
//example.com
/book
?length=17;width=19
?depth=21&height=29#glossary
#chapter1
2014/09/24 APIconUK 2014 166 / 149