added recipe to use appsettings on server side.

docs/recipes/patterns/add-application-configuration.md

@@ -0,0 +1,107 @@
+# How do I add Appliation configuration (appsettings.json)?
+
+This recipe describe how to add application configuration to the server. It uses the regular dotnet middleware
+
+## configure server project
+
+### create appsettings.json
+
+1. create the **appsettings.json** file und src/Server with following content
+
+    ```json
+    {
+        "AppSettings" : {
+            "Setting1": "Value1",
+            "Setting2": "Value2"
+        }
+    }
+    ```
+
+1. update the **src/Server/Server.fsproj** file with the following entry 
+    ```xml 
+    <ItemGroup>
+        <None Include="appsettings.json" CopyToPublishDirectory="Always" />
+    </ItemGroup>
+    ```
+
+### add middleware in **Server.fs**
+
+1. open modules
+
+    ```fs
+    open Microsoft.Extensions.DependencyInjection
+    open Microsoft.Extensions.Configuration
+    open Microsoft.AspNetCore.Http
+    ```
+
+1. change addTodo function of todosApi like that
+
+    ```fs
+    let todosApi (context: HttpContext) = {
+
+        addTodo = fun todo -> async {
+                    // get configuration from appSettings (automatically loaded when appsettings.json present)
+                    let configuration = context.GetService<IConfiguration>()
+
+                    let appSettings = configuration.GetSection("AppSettings")
+                    let setting1 = appSettings["Setting1"]
+                    printfn $"Setting1 in addTodo: {setting1}"
+
+                    return
+                        match Storage.addTodo todo with
+                        | Ok() -> todo
+                        | Error e -> failwith e
+                }
+    }
+    ```
+
+1. add configureServices before application
+
+    ```fs 
+    let configureServices (services : IServiceCollection) =
+        // in case you need an environment specific settings file
+        // let settingsFile = "appsettings." + Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") + ".json"
+        let settingsFile = "appsettings.json"
+
+        let configBuilder = ConfigurationBuilder()
+        let config = configBuilder.AddJsonFile(settingsFile).Build()
+
+        // in case one wants to read configuration and use it while preparing services etc.
+
+        // test loaded settings
+        let s1 = config["AppSettings:Setting1"]
+        printfn $"Setting1: {s1}"
+
+        // load section and then get setting
+        let appSettings = config.GetSection("AppSettings")
+        let setting = appSettings["Setting1"]
+        printfn $"Setting1: {setting}"
+
+        services
+
+    ```
+
+1. change Remoting.fromValue in webApp function into Remoting.fromContext
+
+    ```fs
+    let webApp =
+        Remoting.createApi ()
+        |> Remoting.withRouteBuilder Route.builder
+        |> Remoting.fromContext todosApi 
+        |> Remoting.buildHttpHandler
+
+    ```
+
+1. add service_config in application
+
+    ```fs 
+        let app = application {
+            use_router webApp
+            service_config configureServices // only needed to prepare further services
+            memory_cache
+            use_static "public"
+            use_gzip
+        }
+    ```
+
+

mkdocs.yml

@@ -8,28 +8,28 @@ site_url: http://safe-stack.github.io/docs/
 repo_name: SAFE-Stack/docs
 repo_url: https://github.com/SAFE-Stack/docs
 theme:
-  name: "material"
-  custom_dir: "theme"
-  palette:
-    primary: "light blue"
-    accent: "indigo"
-  logo: img/safe_favicon.png
+    name: "material"
+    custom_dir: "theme"
+    palette:
+        primary: "light blue"
+        accent: "indigo"
+    logo: img/safe_favicon.png
 
 markdown_extensions:
-  - admonition
-  - codehilite
-  - pymdownx.tabbed:
-      alternate_style: true
-  - pymdownx.superfences:
-      custom_fences:
-        - name: mermaid
-          class: mermaid
-          format: !!python/name:pymdownx.superfences.fence_div_format
+    - admonition
+    - codehilite
+    - pymdownx.tabbed:
+          alternate_style: true
+    - pymdownx.superfences:
+          custom_fences:
+              - name: mermaid
+                class: mermaid
+                format: !!python/name:pymdownx.superfences.fence_div_format
 
 extra_css:
-  - https://unpkg.com/[email protected]/dist/mermaid.css
+    - https://unpkg.com/[email protected]/dist/mermaid.css
 extra_javascript:
-  - https://unpkg.com/[email protected]/dist/mermaid.min.js
+    - https://unpkg.com/[email protected]/dist/mermaid.min.js
 
 extra:
   social:
@@ -116,6 +116,7 @@ nav:
           - Sync NuGet and NPM Packages: "recipes/package-management/sync-nuget-and-npm-packages.md"
       - Patterns:
           - Use Dependency Injection: "recipes/patterns/add-dependency-injection.md"
+          - Use Application Configuration: "recipes/patterns/add-application-configuration.md"
       - Client / Server:
           - Use Giraffe instead of Saturn: "recipes/client-server/saturn-to-giraffe.md"
           - Handle server errors on the client: "recipes/client-server/server-errors-on-client.md"