Added support for updating releases

README.md

@@ -19,7 +19,8 @@ Encourage and help software developers set up their releases to be fully automat
 # Shipkit Changelog Gradle plugin
 
 Our plugin generates changelog based on commit history and Github pull requests/issues. 
-Optionally, the changelog content can be posted to Github Releases.
+Optionally, the changelog content can be posted to Github Releases
+(as a new release or updating an existing release for a given tag).
 This plugin is very small (<1kloc) and has a single dependency "com.eclipsesource.minimal-json:minimal-json:0.9.5".
 The dependency is very small (30kb), stable (no changes since 2017), and brings zero transitive dependencies.
 
@@ -182,7 +183,10 @@ Pick the best tool that work for you and start automating releases and changelog
 
 ### Posting Github releases
 
-Uses Github REST API to post releases. 
+Uses Github REST API to post releases.
+First, the code checks if the release _already exists_ for the given tag.
+If it exists, the release notes are updated ([REST doc](https://docs.github.com/en/rest/releases/releases#update-a-release)).
+If not, the new release is created ([REST doc](https://docs.github.com/en/rest/releases/releases#create-a-release)).
 
 ## Usage
 

src/main/java/org/shipkit/changelog/GithubApi.java

@@ -31,6 +31,10 @@ public String post(String url, String body) throws IOException {
         return doRequest(url, "POST", Optional.of(body)).content;
     }
 
+    public String patch(String url, String body) throws IOException {
+        return doRequest(url, "PATCH", Optional.of(body)).content;
+    }
+
     public Response get(String url) throws IOException {
         return doRequest(url, "GET", Optional.empty());
     }
@@ -39,9 +43,15 @@ private Response doRequest(String urlString, String method, Optional<String> bod
         URL url = new URL(urlString);
 
         HttpsURLConnection c = (HttpsURLConnection) url.openConnection();
-        c.setRequestMethod(method);
+        //workaround for Java limitation (https://bugs.openjdk.java.net/browse/JDK-7016595), works with GitHub REST API
+        if (method.equals("PATCH")) {
+            c.setRequestMethod("POST");
+        }
         c.setDoOutput(true);
         c.setRequestProperty("Content-Type", "application/json");
+        if (method.equals("PATCH")) {
+            c.setRequestProperty("X-HTTP-Method-Override", "PATCH");
+        }
         if (authToken != null) {
             c.setRequestProperty("Authorization", "token " + authToken);
         }
@@ -83,7 +93,16 @@ private String call(String method, HttpsURLConnection conn) throws IOException {
             String errorMessage =
                 String.format("%s %s failed, response code = %s, response body:%n%s",
                     method, conn.getURL(), conn.getResponseCode(), IOUtil.readFully(conn.getErrorStream()));
-            throw new IOException(errorMessage);
+            throw new ResponseException(conn.getResponseCode(), errorMessage);
+        }
+    }
+
+    public static class ResponseException extends IOException {
+        public final int responseCode;
+
+        public ResponseException(int responseCode, String errorMessage) {
+            super(errorMessage);
+            this.responseCode = responseCode;
         }
     }
 

src/main/java/org/shipkit/github/release/GithubReleaseTask.java

@@ -2,6 +2,7 @@
 
 import com.eclipsesource.json.Json;
 import com.eclipsesource.json.JsonObject;
+import com.eclipsesource.json.JsonValue;
 import org.gradle.api.DefaultTask;
 import org.gradle.api.GradleException;
 import org.gradle.api.logging.Logger;
@@ -14,6 +15,7 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.util.Optional;
 
 public class GithubReleaseTask extends DefaultTask {
 
@@ -142,9 +144,11 @@ public void setNewTagRevision(String newTagRevision) {
         body.add("body", releaseNotesTxt);
 
         GithubApi githubApi = new GithubApi(githubToken);
+
         try {
-            String response = githubApi.post(url, body.toString());
-            String htmlUrl = Json.parse(response).asObject().getString("html_url", "");
+            LOG.lifecycle("Checking if release exists for tag {}...", releaseTag);
+            Optional<Integer> existingRelease = existingRelease(githubApi, url, releaseTag);
+            final String htmlUrl = performRelease(existingRelease, githubApi, url, body.toString());
             LOG.lifecycle("Posted release to Github: " + htmlUrl);
         } catch (IOException e) {
             throw new GradleException("Unable to post release to Github.\n" +
@@ -159,4 +163,48 @@ public void setNewTagRevision(String newTagRevision) {
                     , e);
         }
     }
+
+    /**
+     * Updates an existing release or creates a new release.
+     * @param existingReleaseId if empty, new release will created.
+     *                          If it contains release ID (internal GH identifier) it will update that release
+     * @param githubApi the GH api object
+     * @param url the url to use
+     * @param body payload
+     * @return String with JSON contents
+     * @throws IOException when something goes wrong with REST call / HTTP connectivity
+     */
+    String performRelease(Optional<Integer> existingReleaseId, GithubApi githubApi, String url, String body) throws IOException {
+        final String htmlUrl;
+        if (existingReleaseId.isPresent()) {
+            LOG.lifecycle("Release already exists for tag {}! Updating the release notes...", releaseTag);
+
+            String response = githubApi.patch(url + "/" + existingReleaseId.get(), body);
+            htmlUrl = Json.parse(response).asObject().getString("html_url", "");
+        } else {
+            String response = githubApi.post(url, body);
+            htmlUrl = Json.parse(response).asObject().getString("html_url", "");
+        }
+        return htmlUrl;
+    }
+
+    /**
+     * Finds out if the release for given tag already exists
+     *
+     * @param githubApi api object
+     * @param url main REST url
+     * @param releaseTag the tag name, will be appended to the url
+     * @return existing release ID or empty optional if there is no release for the given tag
+     * @throws IOException when something goes wrong with REST call / HTTP connectivity
+     */
+    Optional<Integer> existingRelease(GithubApi githubApi, String url, String releaseTag) throws IOException {
+        try {
+            GithubApi.Response r = githubApi.get(url + "/tags/" + releaseTag);
+            JsonValue result = Json.parse(r.getContent());
+            int releaseId = result.asObject().getInt("id", -1);
+            return Optional.of(releaseId);
+        } catch (GithubApi.ResponseException e) {
+            return Optional.empty();
+        }
+    }
 }

src/test/groovy/org/shipkit/changelog/GithubReleaseTaskTest.groovy

@@ -0,0 +1,84 @@
+package org.shipkit.changelog
+
+import org.gradle.api.GradleException
+import org.gradle.testfixtures.ProjectBuilder
+import org.shipkit.github.release.GithubReleasePlugin
+import org.shipkit.github.release.GithubReleaseTask
+import spock.lang.Specification
+
+class GithubReleaseTaskTest extends Specification {
+
+    def apiMock = Mock(GithubApi)
+    def project = ProjectBuilder.builder().build()
+
+    def setup() {
+        project.plugins.apply(GithubReleasePlugin)
+    }
+
+    def "knows if release already exists"() {
+        GithubReleaseTask task = project.tasks.githubRelease
+        apiMock.get("dummy/releases/tags/v1.2.3") >> new GithubApi.Response('{"id": 10}', '')
+
+        when:
+        def result = task.existingRelease(apiMock, "dummy/releases", "v1.2.3")
+
+        then:
+        result.get() == 10
+    }
+
+    def "knows if release does not yet exist"() {
+        GithubReleaseTask task = project.tasks.githubRelease
+        apiMock.get("dummy/releases/tags/v1.2.3") >> { throw new GithubApi.ResponseException(404, "") }
+
+        when:
+        def result = task.existingRelease(apiMock, "dummy/releases", "v1.2.3")
+
+        then:
+        !result.present
+    }
+
+    def "creates new release"() {
+        GithubReleaseTask task = project.tasks.githubRelease
+        apiMock.post("dummy/url", "dummy body") >> '{"html_url": "dummy html url"}'
+
+        when:
+        def result = task.performRelease(Optional.empty(), apiMock, "dummy/url", "dummy body")
+
+        then:
+        result == "dummy html url"
+    }
+
+    def "updates existing release"() {
+        GithubReleaseTask task = project.tasks.githubRelease
+        apiMock.patch("api/releases/123", "dummy body") >> '{"html_url": "dummy html url"}'
+
+        when:
+        def result = task.performRelease(Optional.of(123), apiMock, "api/releases", "dummy body")
+
+        then:
+        result == "dummy html url"
+    }
+
+    /**
+     * Update githubToken and repo name for manual integration testing
+     */
+    def "manual integration test"() {
+        project.version = "1.2.4"
+        project.file("changelog.md") << "Spanking new release! " + System.currentTimeSeconds()
+        project.tasks.named("githubRelease") { GithubReleaseTask it ->
+            it.changelog = project.file("changelog.md")
+            it.repository = "mockitoguy/shipkit-demo" //feel free to change to your private repo
+            it.newTagRevision = "aa51a6fe99d710c0e7ca30fc1d0411a8e9cdb7a8" //use sha of the repo above
+            it.githubToken = "secret" //update, use your token, DON'T CHECK IN
+        }
+
+        when:
+        project.tasks.githubRelease.postRelease()
+
+        then:
+        //when doing manual integration testing you won't get an exception here
+        //remove below / change the assertion when integ testing
+        thrown(GradleException)
+//        true
+    }
+}

version.properties

@@ -1 +1 @@
-version=1.1.*
+version=1.2.*