Understanding the concept of serverless solutions is the first step. The next step is to create solutions using the technologies available. In this session I'll show you how you can leverage the power of Azure Functions. We will pick a real-life scenario and convert this to a serverless design. We will be building the solution using Azure Functions, CosmosDB and many more services available.

4. servers

5. Like PaaS

6. “If your PaaS can efficiently start instances in
20ms that run for half a second, then call it
serverless.”
Adrian Cockcroft - VP Cloud Architecture Strategy AWS

7. Keep It Small and Simple

9. URL Minification

10. GET minified URL redirect
CREATE minified URL

11. CosmosDB

12. Oh yeah!

14. Web App CosmosDB

16. CosmosDB
GET
POST

17. CosmosDB
GET
POST
Azure cache
UPDATE Change
Feed

18. CosmosDB
GET
POST
Azure cache
UPDATE
Change
Feed
Queue TRIGGER

19. CosmosDB
GET
POST

20. Bindings are your friend

21. "bindings": [
{
"type": "httpTrigger",
"route": "{slug}",
"methods": [
"get"
],
"authLevel": "anonymous",
"name": "req"
}
],
Function, User, System & Admin

22. "bindings": [
{
"name": “minifiedUrl",
"type": "documentDB",
"databaseName": “MinifyRepository",
"collectionName": “MinifiedUrls",
"createIfNotExists": true,
"connection": “CosmosDbConnection",
"direction": "out"
}
],

23. Don’t write JSON

25. Where to put the code

26. Existing patterns &
principles still apply!

27. private readonly ICosmosClient cosmosClient;
public CreateUrlHandler()
{
this.cosmosClient = new CosmosClient();
}
public CreateUrlHandler(ICosmosClient cosmosClient)
{
this.cosmosClient = cosmosClient;
}

29. CosmosDB
GET
POST

32. [FunctionName("Get")]
public static async Task<HttpResponseMessage> Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "{slug}")]
HttpRequestMessage req,
string slug,
TraceWriter log)
{
var getUrl = new GetUrlHandler();
var minifiedUrl = await getUrl.Execute(slug);
if (minifiedUrl == null)
{
return req.CreateErrorResponse(HttpStatusCode.NotFound,
$"Minified value `{slug}` is not found.");
}
var response = req.CreateResponse(HttpStatusCode.Redirect);
response.Headers.Location = new Uri(minifiedUrl.FullUrl);
return response;
}

33. public static class Create
{
[FunctionName("Create")]
public static HttpResponseMessage Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "post", Route = "create")]
HttpRequestMessage req,
[DocumentDB("datbaseName", "collectionName",
PartitionKey = "MinifiedUrls",
CreateIfNotExists = true,
ConnectionStringSetting = "minifiedUrlConnectionString")]
out dynamic minifiedUrl,
TraceWriter log)
{
string jsonContent = req.Content.ReadAsStringAsync().Result;
var data = JsonConvert.DeserializeObject<MinifiedUrl>(jsonContent);
var create = new CreateUrlHandler();
minifiedUrl = create.Execute(data);
return req.CreateResponse(HttpStatusCode.Created,
$"api/{data.MinifiedSlug}");
}
}

35. Easy mode

38. master branch
to production

39. Pro mode

42. Check if you use slots
Point to the correct package

46. https://my.jdv.li/api/minifiedurl
or
https://my.jdv.li/minifiedurl

47. {
"$schema": "http://json.schemastore.org/proxies",
"proxies": {
"getminifiedredirect": {
"matchCondition": {
"methods": [ "GET" ],
"route": "/{slug}"
},
"backendUri": "https://%WEBSITE_HOSTNAME%/api/{slug}"
}
}
}
Matching conditions

48. https://github.com/Jandev/minifier
@Jan_de_V
jandv@4dotnet.nl
https://jan-v.nl