docs/csharp/asynchronous-programming/snippets/generate-consume-asynchronous-streams/finished/Program.cs - main - aprogrammer/dotnet-docs

docs/csharp/asynchronous-programming/snippets/generate-consume-asynchronous-streams/finished/Program.cs
182 строки6 KB
Bill Wagner
Create async section (#33921)
13 фев 2023, 19:07
13 фев 2023, 19:0753bc3af
using System.Runtime.CompilerServices;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using Octokit;

namespace GitHubActivityReport;

public class GraphQLRequest
{
    [JsonProperty("query")]
    public string? Query { get; set; }

    [JsonProperty("variables")]
    public IDictionary<string, object> Variables { get; } = new Dictionary<string, object>();

    public string ToJsonText() =>
        JsonConvert.SerializeObject(this);
}

class Program
{
    internal const string PagedIssueQuery =
@"query ($repo_name: String!,  $start_cursor:String) {
  repository(owner: ""dotnet"", name: $repo_name) {
    issues(last: 25, before: $start_cursor)
     {
        totalCount
        pageInfo {
          hasPreviousPage
          startCursor
        }
        nodes {
          title
          number
          createdAt
        }
      }
    }
  }
";

    static async Task Main(string[] args)
    {
        //Follow these steps to create a GitHub Access Token
        // https://help.github.com/articles/creating-a-personal-access-token-for-the-command-line/#creating-a-token
        //Select the following permissions for your GitHub Access Token:
        // - repo:status
        // - public_repo
        // Replace the 3rd parameter to the following code with your GitHub access token.
        var key = GetEnvVariable("GitHubKey",
        "You must store your GitHub key in the 'GitHubKey' environment variable",
        "");

        var client = new GitHubClient(new Octokit.ProductHeaderValue("IssueQueryDemo"))
        {
            Credentials = new Octokit.Credentials(key)
        };

        // <SnippetEnumerateAsyncStream>
        int num = 0;
        await foreach (var issue in RunPagedQueryAsync(client, PagedIssueQuery, "docs"))
        {
            Console.WriteLine(issue);
            Console.WriteLine($"Received {++num} issues in total");
        }
        // </SnippetEnumerateAsyncStream>

    }

    // <SnippetEnumerateWithCancellation>
    private static async Task EnumerateWithCancellation(GitHubClient client)
    {
        int num = 0;
        var cancellation = new CancellationTokenSource();
        await foreach (var issue in RunPagedQueryAsync(client, PagedIssueQuery, "docs")
            .WithCancellation(cancellation.Token))
        {
            Console.WriteLine(issue);
            Console.WriteLine($"Received {++num} issues in total");
        }
    }
    // </SnippetEnumerateWithCancellation>

    // <SnippetGenerateAsyncStream>
    // <SnippetUpdateSignature>
    private static async IAsyncEnumerable<JToken> RunPagedQueryAsync(GitHubClient client,
        string queryText, string repoName)
    // </SnippetUpdateSignature>
    {
        var issueAndPRQuery = new GraphQLRequest
        {
            Query = queryText
        };
        issueAndPRQuery.Variables["repo_name"] = repoName;

        bool hasMorePages = true;
        int pagesReturned = 0;
        int issuesReturned = 0;

        // Stop with 10 pages, because these are large repos:
        while (hasMorePages && (pagesReturned++ < 10))
        {
            var postBody = issueAndPRQuery.ToJsonText();
            var response = await client.Connection.Post<string>(new Uri("https://api.github.com/graphql"),
                postBody, "application/json", "application/json");

            JObject results = JObject.Parse(response.HttpResponse.Body.ToString()!);

            int totalCount = (int)issues(results)["totalCount"]!;
            hasMorePages = (bool)pageInfo(results)["hasPreviousPage"]!;
            issueAndPRQuery.Variables["start_cursor"] = pageInfo(results)["startCursor"]!.ToString();
            issuesReturned += issues(results)["nodes"]!.Count();

            // <SnippetYieldReturnPage>
            foreach (JObject issue in issues(results)["nodes"]!)
                yield return issue;
            // </SnippetYieldReturnPage>
        }

        JObject issues(JObject result) => (JObject)result["data"]!["repository"]!["issues"]!;
        JObject pageInfo(JObject result) => (JObject)issues(result)["pageInfo"]!;
    }
    // </SnippetGenerateAsyncStream>

    // <SnippetGenerateWithCancellation>
    private static async IAsyncEnumerable<JToken> RunPagedQueryAsync(GitHubClient client,
        string queryText, string repoName, [EnumeratorCancellation] CancellationToken cancellationToken = default)
    {
        var issueAndPRQuery = new GraphQLRequest
        {
            Query = queryText
        };
        issueAndPRQuery.Variables["repo_name"] = repoName;

        bool hasMorePages = true;
        int pagesReturned = 0;
        int issuesReturned = 0;

        // Stop with 10 pages, because these are large repos:
        while (hasMorePages && (pagesReturned++ < 10))
        {
            var postBody = issueAndPRQuery.ToJsonText();
            var response = await client.Connection.Post<string>(new Uri("https://api.github.com/graphql"),
                postBody, "application/json", "application/json");

            JObject results = JObject.Parse(response.HttpResponse.Body.ToString()!);

            int totalCount = (int)issues(results)["totalCount"]!;
            hasMorePages = (bool)pageInfo(results)["hasPreviousPage"]!;
            issueAndPRQuery.Variables["start_cursor"] = pageInfo(results)["startCursor"]!.ToString();
            issuesReturned += issues(results)["nodes"]!.Count();

            // <SnippetYieldReturnPage>
            foreach (JObject issue in issues(results)["nodes"]!)
                yield return issue;
            // </SnippetYieldReturnPage>
        }

        JObject issues(JObject result) => (JObject)result["data"]!["repository"]!["issues"]!;
        JObject pageInfo(JObject result) => (JObject)issues(result)["pageInfo"]!;
    }
    // </SnippetGenerateWithCancellation>

    private static string GetEnvVariable(string item, string error, string defaultValue)
    {
        var value = Environment.GetEnvironmentVariable(item);
        if (string.IsNullOrWhiteSpace(value))
        {
            if (!string.IsNullOrWhiteSpace(defaultValue))
            {
                return defaultValue;
            }

            if (!string.IsNullOrWhiteSpace(error))
            {
                Console.WriteLine(error);
                Environment.Exit(0);
            }
        }
        return value ?? String.Empty;
    }
}