Added configuration for the auto populating headers and auto recogniz…

…ing the input

Closes #21, #22

README.md

@@ -1,2 +1,76 @@
 # crest
 Command line REST client
+
+### Configuration Files
+
+The operation of this program can be modified by the existance of configuration files. Specifically,
+you can place a `.crestconfig.json` file in your home directory, or in the directory from which
+you are running `crest`. (Say, for example, the project directory where you are developing your
+web service.) In this way you can customize the program operation for the needs of a given 
+project.
+
+A configuration file in the local directory will override any settings found in the global file (the one
+in your home directory), and many of the settings can also be overridden by command line
+options.
+
+The configuration files are JSON files consisting of a single dictionary where each key is
+one of the following, and the contents are as described.
+
+E.g.
+
+    {
+        "Private": true,
+        "URLPrefix": "http://mytestserver.local:8080/api/v2"
+    }
+
+#### AutoPopulateRequestHeaders
+
+By default `crest` adds a number of request headers automatically. They can be overridden
+by manually specifying headers of the same name, but you can turn off the auto headers
+completely by setting this to `false`. In that case only the headers that are absolutely required
+for the HTTP protocol will be added.
+
+e.g. `"AutoPopulateRequestHeaders": false` (Default is `true`)
+
+This is also turn off if `--no-auto-headers` is specified on the command line.
+
+#### AutoRecognizeRequestContent
+
+By default `crest` will attempt to identify the contents of the standard input and set the
+`Content-Type` header appropriately. However, there are the following limitations:
+
+1. Presently only JSON and XML data are recognized.
+2. If the data is too large (by default over 2048 bytes), then it will be sent as chunked data
+ to avoid keeping the entire contents in memory at once. In this case it will not be 
+ recognized.
+
+ By turning this off no `Content-Type` header will be added automatically, and you will
+ need to add it manually via the command line options.
+
+ e.g. `"AutoRecognizeRequestContent": false` (Default is `true`)
+
+ This is also turn off if `--no-auto-headers` is specified on the command line.
+
+#### Private
+
+By default `crest` adds a `User-Agent` key that includes information about the machine you
+are running on. For example: `Crest/1.0.0 (macOS; Version 11.2.3 (Build 20D91); x86_64)`.
+If you set `Private` to `true`, then the details will be left out and the `User-Agent` will simply
+be reported as `Crest`. (You can override this as well by specifying your own `User_Agent` header
+either in the configuration files or via the command line.)
+
+E.g. `"Private": true` (Default is `false`)
+
+#### URLPrefix
+
+This can be used to set a prefix that will automatically be prepended to the URL given on the command
+line. This is likely to be most useful in the local `.crestconfig.json` where you can set it to be
+the common part of the web service you are testing. This can save you a lot of typing.
+
+Note that the `URLPrefix` will be ignored if the command line URL begins with `http:` or
+`https:`.
+
+E.g. `"URLPrefix": "http://mytestserver.local:8080/api/v2"` (Default is empty)
+
+In this example, if you run the command `crest /contract/id871` it will actually perform 
+a `GET` to the URL `http://mytestserver.local:8080/api/v2/contract/id871`.

Sources/CrestLib/Configuration.swift

@@ -10,7 +10,10 @@ import Foundation
 
 
 public struct Configuration {
-    var URLPrefix: String? = nil
+    var autoPopulateRequestHeaders: Bool? = nil
+    var autoRecognizeRequestContent: Bool? = nil
+    var isPrivate: Bool? = nil
+    var urlPrefix: String? = nil
 
     static var shared = Configuration()
 
@@ -20,7 +23,10 @@ public struct Configuration {
         manager.load(file: filename, relativeFrom: .customPath(homeDirectory))
             .load(file: filename, relativeFrom: .pwd)
             .load(overloads)
-        shared.URLPrefix = manager["URLPrefix"] as? String
+        shared.autoPopulateRequestHeaders = manager["AutoPopulateRequestHeaders"] as? Bool
+        shared.autoRecognizeRequestContent = manager["AutoRecognizeRequestContent"] as? Bool
+        shared.isPrivate = manager["Private"] as? Bool
+        shared.urlPrefix = manager["URLPrefix"] as? String
 
         print("!! config: \(shared)")
     }

Sources/CrestLib/Operation.swift

@@ -39,18 +39,27 @@ public struct Operation {
 
     private func urlAsString() -> String {
         if url.scheme == nil {
-            if let prefix = Configuration.shared.URLPrefix {
+            if let prefix = Configuration.shared.urlPrefix {
                 return prefix + url.absoluteString
             }
         }
         return url.absoluteString
     }
 
     private func addHeadersToRequest(_ request: inout HTTPClient.Request) {
-        let platform = Platform()
         request.headers.add(name: "Host", value: "\(request.host):\(request.port)")
-        request.headers.add(name: "User-Agent", value: "Crest/\(VERSION) (\(platform.operatingSystem); \(platform.operatingSystemVersion); \(platform.hardware))")
-        request.headers.add(name: "Accept", value: "*/*")
+        if Configuration.shared.autoPopulateRequestHeaders ?? true {
+            request.headers.add(name: "User-Agent", value: getUserAgent())
+            request.headers.add(name: "Accept", value: "*/*")
+        }
+    }
+
+    private func getUserAgent() -> String {
+        if Configuration.shared.isPrivate ?? false {
+            return "Crest"
+        }
+        let platform = Platform()
+        return "Crest/\(VERSION) (\(platform.operatingSystem); \(platform.operatingSystemVersion); \(platform.hardware))"
     }
 
     // This "ugliness" is needed for the streaming requests since we need the stream
@@ -88,7 +97,9 @@ public struct Operation {
                         } else if (try? XMLDocument(data: data)) != nil {
                             contentType = "application/xml"
                         }
-                        request.headers.add(name: "Content-Type", value: contentType)
+                        if Configuration.shared.autoRecognizeRequestContent ?? true {
+                            request.headers.add(name: "Content-Type", value: contentType)
+                        }
                         request.body = .string(s)
                         return
                     }

Sources/crest/main.swift

@@ -11,9 +11,12 @@ struct Crest: ParsableCommand {
         version: CrestLib.VERSION
     )
 
-    @Option(name: .shortAndLong, help: "The HTTP method (defaults to GET)")
+    @Option(name: .shortAndLong, help: "The HTTP method (defaults to GET).")
     var method: HTTPMethod = .GET
 
+    @Flag(help: "Turn off the auto-population of headers.")
+    var noAutoHeaders = false
+
     @Argument(help: "The URL of the service to contact.")
     var url: String
 
@@ -37,6 +40,10 @@ struct Crest: ParsableCommand {
 
     func commandLineOverrides() -> [String: Any?] {
         var overrides = [String: Any?]()
+        if noAutoHeaders {
+            overrides["AutoPopulateRequestHeaders"] = false
+            overrides["AutoRecognizeRequestContent"] = false
+        }
         return overrides
     }
 }