Imported Upstream version 1.0.1

api/graph.go

@@ -0,0 +1,84 @@
+package api
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"mime"
+	"os"
+	"os/exec"
+
+	"github.com/gin-gonic/gin"
+	"github.com/smira/aptly/deb"
+)
+
+// GET /api/graph.:ext?layout=[vertical|horizontal(default)]
+func apiGraph(c *gin.Context) {
+	var (
+		err    error
+		output []byte
+	)
+
+	ext := c.Params.ByName("ext")
+	layout := c.Request.URL.Query().Get("layout")
+
+	factory := context.CollectionFactory()
+
+	factory.RemoteRepoCollection().RLock()
+	defer factory.RemoteRepoCollection().RUnlock()
+	factory.LocalRepoCollection().RLock()
+	defer factory.LocalRepoCollection().RUnlock()
+	factory.SnapshotCollection().RLock()
+	defer factory.SnapshotCollection().RUnlock()
+	factory.PublishedRepoCollection().RLock()
+	defer factory.PublishedRepoCollection().RUnlock()
+
+	graph, err := deb.BuildGraph(factory, layout)
+	if err != nil {
+		c.JSON(500, err)
+		return
+	}
+
+	buf := bytes.NewBufferString(graph.String())
+
+	if ext == "dot" || ext == "gv" {
+		// If the raw dot data is requested, return it as string.
+		// This allows client-side rendering rather than server-side.
+		c.String(200, buf.String())
+		return
+	}
+
+	command := exec.Command("dot", "-T"+ext)
+	command.Stderr = os.Stderr
+
+	stdin, err := command.StdinPipe()
+	if err != nil {
+		c.Fail(500, err)
+		return
+	}
+
+	_, err = io.Copy(stdin, buf)
+	if err != nil {
+		c.Fail(500, err)
+		return
+	}
+
+	err = stdin.Close()
+	if err != nil {
+		c.Fail(500, err)
+		return
+	}
+
+	output, err = command.Output()
+	if err != nil {
+		c.Fail(500, fmt.Errorf("unable to execute dot: %s (is graphviz package installed?)", err))
+		return
+	}
+
+	mimeType := mime.TypeByExtension("." + ext)
+	if mimeType == "" {
+		mimeType = "application/octet-stream"
+	}
+
+	c.Data(200, mimeType, output)
+}