## - Fetch for the JavaScript target: https://developer.mozilla.org/docs/Web/API/Fetch_API
when not defined(js):
{.fatal: "Module jsfetch is designed to be used with the JavaScript backend.".}
import std/[asyncjs, jsformdata, jsheaders]
export jsformdata, jsheaders
from std/httpcore import HttpMethod
from std/jsffi import JsObject
type
FetchOptions* = ref object of JsRoot ## Options for Fetch API.
keepalive*: bool
metod* {.importjs: "method".}: cstring
body*, integrity*, referrer*, mode*, credentials*, cache*, redirect*, referrerPolicy*: cstring
headers*: Headers
FetchModes* = enum ## Mode options.
fmCors = "cors"
fmNoCors = "no-cors"
fmSameOrigin = "same-origin"
FetchCredentials* = enum ## Credential options. See https://developer.mozilla.org/en-US/docs/Web/API/Request/credentials
fcInclude = "include"
fcSameOrigin = "same-origin"
fcOmit = "omit"
FetchCaches* = enum ## https://developer.mozilla.org/docs/Web/API/Request/cache
fchDefault = "default"
fchNoStore = "no-store"
fchReload = "reload"
fchNoCache = "no-cache"
fchForceCache = "force-cache"
FetchRedirects* = enum ## Redirects options.
frFollow = "follow"
frError = "error"
frManual = "manual"
FetchReferrerPolicies* = enum ## Referrer Policy options.
frpNoReferrer = "no-referrer"
frpNoReferrerWhenDowngrade = "no-referrer-when-downgrade"
frpOrigin = "origin"
frpOriginWhenCrossOrigin = "origin-when-cross-origin"
frpUnsafeUrl = "unsafe-url"
Response* = ref object of JsRoot ## https://developer.mozilla.org/en-US/docs/Web/API/Response
bodyUsed*, ok*, redirected*: bool
typ* {.importjs: "type".}: cstring
url*, statusText*: cstring
status*: cint
headers*: Headers
body*: cstring
Request* = ref object of JsRoot ## https://developer.mozilla.org/en-US/docs/Web/API/Request
bodyUsed*, ok*, redirected*: bool
typ* {.importjs: "type".}: cstring
url*, statusText*: cstring
status*: cint
headers*: Headers
body*: cstring
func newResponse*(body: cstring | FormData): Response {.importjs: "(new Response(#))".}
## Constructor for `Response`. This does *not* call `fetch()`. Same as `new Response()`.
func newRequest*(url: cstring): Request {.importjs: "(new Request(#))".}
## Constructor for `Request`. This does *not* call `fetch()`. Same as `new Request()`.
func newRequest*(url: cstring; fetchOptions: FetchOptions): Request {.importjs: "(new Request(#, #))".}
## Constructor for `Request` with `fetchOptions`. Same as `fetch(url, fetchOptions)`.
func clone*(self: Response | Request): Response {.importjs: "#.$1()".}
## https://developer.mozilla.org/en-US/docs/Web/API/Response/clone
proc text*(self: Response): Future[cstring] {.importjs: "#.$1()".}
## https://developer.mozilla.org/en-US/docs/Web/API/Response/text
proc json*(self: Response): Future[JsObject] {.importjs: "#.$1()".}
## https://developer.mozilla.org/en-US/docs/Web/API/Response/json
proc formData*(self: Response): Future[FormData] {.importjs: "#.$1()".}
## https://developer.mozilla.org/en-US/docs/Web/API/Response/formData
proc unsafeNewFetchOptions*(metod, body, mode, credentials, cache, referrerPolicy: cstring;
keepalive: bool; redirect = "follow".cstring; referrer = "client".cstring; integrity = "".cstring; headers: Headers = newHeaders()): FetchOptions {.importjs:
"{method: #, body: #, mode: #, credentials: #, cache: #, referrerPolicy: #, keepalive: #, redirect: #, referrer: #, integrity: #, headers: #}".}
## .. warning:: Unsafe `newfetchOptions`.
func newfetchOptions*(metod = HttpGet; body: cstring = nil;
mode = fmCors; credentials = fcSameOrigin; cache = fchDefault; referrerPolicy = frpNoReferrerWhenDowngrade;
keepalive = false; redirect = frFollow; referrer = "client".cstring; integrity = "".cstring,
headers: Headers = newHeaders()): FetchOptions =
## Constructor for `FetchOptions`.
result = FetchOptions(
body: if metod notin {HttpHead, HttpGet}: body else: nil,
mode: cstring($mode), credentials: cstring($credentials), cache: cstring($cache), referrerPolicy: cstring($referrerPolicy),
keepalive: keepalive, redirect: cstring($redirect), referrer: referrer, integrity: integrity, headers: headers,
metod: (case metod
of HttpHead: "HEAD".cstring
of HttpGet: "GET".cstring
of HttpPost: "POST".cstring
of HttpPut: "PUT".cstring
of HttpDelete: "DELETE".cstring
of HttpPatch: "PATCH".cstring
else: "GET".cstring
)
)
proc fetch*(url: cstring | Request): Future[Response] {.importjs: "$1(#)".}
## `fetch()` API, simple `GET` only, returns a `Future[Response]`.
proc fetch*(url: cstring | Request; options: FetchOptions): Future[Response] {.importjs: "$1(#, #)".}
## `fetch()` API that takes a `FetchOptions`, returns a `Future[Response]`.
func toCstring*(self: Request | Response | FetchOptions): cstring {.importjs: "JSON.stringify(#)".}
func `$`*(self: Request | Response | FetchOptions): string = $toCstring(self)
runnableExamples("-r:off"):
import std/[asyncjs, jsconsole, jsformdata, jsheaders]
from std/httpcore import HttpMethod
from std/jsffi import JsObject
from std/sugar import `=>`
block:
let options0: FetchOptions = unsafeNewFetchOptions(
metod = "POST".cstring,
body = """{"key": "value"}""".cstring,
mode = "no-cors".cstring,
credentials = "omit".cstring,
cache = "no-cache".cstring,
referrerPolicy = "no-referrer".cstring,
keepalive = false,
redirect = "follow".cstring,
referrer = "client".cstring,
integrity = "".cstring,
headers = newHeaders()
)
assert options0.keepalive == false
assert options0.metod == "POST".cstring
assert options0.body == """{"key": "value"}""".cstring
assert options0.mode == "no-cors".cstring
assert options0.credentials == "omit".cstring
assert options0.cache == "no-cache".cstring
assert options0.referrerPolicy == "no-referrer".cstring
assert options0.redirect == "follow".cstring
assert options0.referrer == "client".cstring
assert options0.integrity == "".cstring
assert options0.headers.len == 0
block:
let options1: FetchOptions = newFetchOptions(
metod = HttpPost,
body = """{"key": "value"}""".cstring,
mode = fmNoCors,
credentials = fcOmit,
cache = fchNoCache,
referrerPolicy = frpNoReferrer,
keepalive = false,
redirect = frFollow,
referrer = "client".cstring,
integrity = "".cstring,
headers = newHeaders()
)
assert options1.keepalive == false
assert options1.metod == $HttpPost
assert options1.body == """{"key": "value"}""".cstring
assert options1.mode == $fmNoCors
assert options1.credentials == $fcOmit
assert options1.cache == $fchNoCache
assert options1.referrerPolicy == $frpNoReferrer
assert options1.redirect == $frFollow
assert options1.referrer == "client".cstring
assert options1.integrity == "".cstring
assert options1.headers.len == 0
block:
let response: Response = newResponse(body = "-. .. --".cstring)
let request: Request = newRequest(url = "http://nim-lang.org".cstring)
if not defined(nodejs):
block:
proc doFetch(): Future[Response] {.async.} =
fetch "https://httpbin.org/get".cstring
proc example() {.async.} =
let response: Response = await doFetch()
assert response.ok
assert response.status == 200.cint
assert response.headers is Headers
assert response.body is cstring
discard example()
block:
proc example2 {.async.} =
await fetch("https://api.github.com/users/torvalds".cstring)
.then((response: Response) => response.json())
.then((json: JsObject) => console.log(json))
.catch((err: Error) => console.log("Request Failed", err))
discard example2()