此时我使用的是Xcode 8.3.3。 Package.swift 包含：
let package = Package(
name: "StripePayment",
dependencies: [
.Package(url: "https://github.com/vapor/vapor.git", majorVersion: 1, minor: 5),
.Package(url:"https://github.com/vapor/jwt.git", majorVersion: 0,minor: 8),
.Package(url: "https://github.com/SwiftyJSON/SwiftyJSON.git", versions: Version(1, 0, 0)..<Version(3, .max, .max))
],
exclude: [
"Config",
"Database",
"Localization",
"Public",
"Resources",
"Tests",
]
)
如果您生成服务帐户凭据，您需要记住以下内容，取自https://cloud.google.com/storage/docs/authentication：您可以在云平台控制台中通过为服务帐号创建OAuth Client ID来创建私钥。您可以获取 JSON 和 PKCS12 格式的私钥：
如果您使用的是 JSON 密钥，则需要应用程序默认凭据 https://cloud.google.com/storage/docs/authentication#libauth在 Google Cloud Platform 之外的生产环境中。JSON 密钥无法转换为其他格式。许多不同的编程语言和库都支持 PKCS12 (.p12)。如果需要，您可以使用 OpenSSL 将密钥转换为其他格式（请参阅将私钥转换为其他格式 https://cloud.google.com/storage/docs/authentication）。但是，PKCS12 密钥无法转换为 JSON 格式。
Note: You do NOT需要在 console.cloud.google.com 生成一个服务帐户。只需按照下面列出的步骤 1...6 进行操作即可。
Go to https://console.firebase.google.com https://console.firebase.google.com，单击您的项目，在“概述”旁边单击滚轮“设置”，单击“服务帐户”，滚动到页面底部，然后单击“生成新私钥”。
-
使用 OpenSSL 将 p.12（又名 pkcs12）文件转换为 .pem（又名 pkcs1）
cat /path/to/xxxx-privatekey.p12 | openssl pkcs12 -nodes -nocerts -passin pass:notasecret | openssl rsa > /path/to/secret.pem
去github并搜索VaporJWT https://github.com/siemensikkema/vapor-jwt并将其导入到 Xcode 中。它将帮助您创建签名的 JSON Web 令牌。
在此 github 页面上，您将了解如何提取私钥以供 RSA 使用。
将 .pem 转换为 der
openssl rsa -in /path/to/secret.pem -outform der -out /path/to/private.der
- 将 .der 转换为 .base64
openssl base64 -in /path/to/private.der -out /path/to/Desktop/private.txt
在 private.txt 中，您拥有以 base64 编码的私钥，您最终可以使用它来签署您的 JWT。然后您可以使用签名的 JWT 调用 Google API。
``
import Vapor
import VaporJWT
let drop = Droplet()
var tokenID:String!
//set current date
let dateNow = Date()
// assign to expDate the validity period of the token returned by OAuth server (3600 seconds)
var expDate = String(Int(dateNow.timeIntervalSince1970 + (60 * 60)))
// assign to iatDate the time when the call was made to request an access token
var iatDate = String(Int(dateNow.timeIntervalSince1970))
// the header of the JSON Web Token (first part of the JWT)
let headerJWT = ["alg":"RS256","typ":"JWT"]
// the claim set of the JSON Web Token
let jwtClaimSet =
["iss":"[email protected] /cdn-cgi/l/email-protection",
"scope":"https://www.googleapis.com/auth/firebase.database",
"aud":"https://www.googleapis.com/oauth2/v4/token",
"exp": expDate,
"iat": iatDate]
//Using VaporJWT construct a JSON Web Token and sign it with RS256 algorithm
//The only signing algorithm supported by the Google OAuth 2.0 Authorization
//Server is RSA using SHA-256 hashing algorithm.
let jwt = try JWT(headers: Node(node: headerJWT), payload: Node(node:jwtClaimSet), encoding: Base64URLEncoding(), signer: RS256(encodedKey: "copy paste here what you have in private.txt as explained at point 7 above "))
// create the JSON Web Token
let JWTtoken = try jwt.createToken()
let grant_type = "urn:ietf:params:oauth:grant-type:jwt-bearer" // this value must not be changed
let unreserved = "*-._"
let allowed = NSMutableCharacterSet.alphanumeric()
allowed.addCharacters(in: unreserved)
// percent or URL encode grant_type
let grant_URLEncoded = grant_type.addingPercentEncoding(withAllowedCharacters: allowed as CharacterSet)
// create a string made of grant_type and assertion. NOTE!!! only grant_type's value is URL encoded.
//JSON Web Token value does not need to be URL encoded
var fullString = "grant_type=\(grant_URLEncoded!)&assertion=\(JWTtoken)"
//pass fullString in the body parameter
drop.get("call") { request in
let response = try drop.client.post("https://www.googleapis.com/oauth2/v4/token", headers: ["Content-Type": "application/x-www-form-urlencoded"], query: [:],body: fullString)
let serverResp = response.headers
let serverBody = response.body.bytes
let serverJson = try JSON(bytes: serverBody!)
print(serverJson)
return "Success"
