[resolves meltwater#89] Add a configuration to set stash page size wh…

…en comparing changes for change set

CHANGELOG.md

@@ -1,3 +1,8 @@
+## Unreleased
+
+### Added
+- [#89](https://github.com/meltwater/drone-convert-pathschanged/issues/89) add environment variable to allow stash users to specify page size of git compare changes
+
 ## 1.0.0
 
 ### Breaking changes

README.md

@@ -125,6 +125,10 @@ $ docker run -d \
   --restart=always \
   --name=converter meltwater/drone-convert-pathschanged
 ```
+Stash APIs are paginated and by default will only return 25 changes when computing the changeset. Set environment variable STASH_PAGE_SIZE to a higher number on the plugin to avoid partial change set detection.
+```console
+--env=STASH_PAGE_SIZE=1000
+```
 
 4. Update your Drone server configuration to include the plugin address and the shared secret.
 

main.go

@@ -34,6 +34,7 @@ type (
 		BitBucketPassword string `envconfig:"BITBUCKET_PASSWORD"`
 		GithubServer      string `envconfig:"GITHUB_SERVER"`
 		StashServer       string `envconfig:"STASH_SERVER"`
+		StashPageSize     int    `envconfig:"STASH_PAGE_SIZE"` //bumps the rest api page size for changeset detection. Picks only 25 changes if unspecified
 	}
 )
 
@@ -120,6 +121,7 @@ func main() {
 		GithubServer:      spec.GithubServer,
 		Token:             spec.Token,
 		StashServer:       spec.StashServer,
+		StashPageSize:     spec.StashPageSize,
 	}
 
 	handler := converter.Handler(

plugin/plugin.go

@@ -27,6 +27,7 @@ type (
 		GithubServer      string
 		StashServer       string
 		Token             string
+		StashPageSize     int
 	}
 
 	plugin struct {
@@ -166,7 +167,11 @@ func (p *plugin) Convert(ctx context.Context, req *converter.Request) (*drone.Co
 				return nil, err
 			}
 		case "stash":
-			changedFiles, err = providers.GetStashFilesChanged(req.Repo, req.Build, p.params.StashServer, p.params.Token, scm.ListOptions{})
+			listOptions := scm.ListOptions{}
+			if p.params.StashPageSize > 0 {
+				listOptions.Size = p.params.StashPageSize
+			}
+			changedFiles, err = providers.GetStashFilesChanged(req.Repo, req.Build, p.params.StashServer, p.params.Token, listOptions)
 			if err != nil {
 				return nil, err
 			}

plugin/plugin_test.go

@@ -605,3 +605,64 @@ name: default
 		t.Log(diff)
 	}
 }
+
+func TestStashPageSizeSetWhenConfigured(t *testing.T) {
+	gock.New("http://example.com:7990").
+		Get("/rest/api/1.0/projects/PRJ/repos/my-repo/compare/changes").
+		MatchParam("from", "4f4b0ef1714a5b6cafdaf2f53c7f5f5b38fb9348").
+		MatchParam("to", "131cb13f4aed12e725177bc4b7c28db67839bf9f").
+		MatchParam("limit", "40"). //this will resolve only if the configured page size was honoured
+		Reply(200).
+		Type("application/json").
+		File("../providers/testdata/stash/compare.json")
+
+	before := `
+kind: pipeline
+type: docker
+name: default
+
+steps:
+- name: message
+  image: busybox
+  commands:
+  - echo "This step will be excluded when .drone.yml is changed"
+  when:
+    paths:
+      exclude:
+      - .drone.yml
+`
+	params := &Params{
+		StashServer:   "http://example.com:7990",
+		Token:         "invalidtoken",
+		StashPageSize: 40,
+	}
+
+	req := &converter.Request{
+		Build: drone.Build{
+			Before: "4f4b0ef1714a5b6cafdaf2f53c7f5f5b38fb9348",
+			After:  "131cb13f4aed12e725177bc4b7c28db67839bf9f",
+		},
+		Config: drone.Config{
+			Data: before,
+		},
+		Repo: drone.Repo{
+			Namespace: "repos",
+			Name:      "my-repo",
+			Slug:      "PRJ/my-repo",
+			Config:    ".drone.yml",
+		},
+	}
+
+	plugin := New("stash", params)
+
+	config, err := plugin.Convert(noContext, req)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	if config == nil { //we are not interested in transformation, only validating limit was set on the request to stash and resolved to gock
+		t.Errorf("Unexpected Results")
+	}
+
+}