dashboard/app: add a JSON output mode for the data on the front page

Fixes golang/go#9493

Change-Id: I4891abf530901c620c2923e9f2d3e3227dd7ced9
Reviewed-on: https://go-review.googlesource.com/2290
Reviewed-by: Andrew Gerrand <adg@golang.org>

dashboard/README

@@ -2,35 +2,29 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-The files in this directory constitute the continuous builder:
+The files in these directories constitute the continuous builder:
 
-app/:     an AppEngine server. The code that runs http://build.golang.org/
+app/:      a.k.a the "dashboard"; the App Engine code that runs http://build.golang.org/
 buildlet/: HTTP server that runs on a VM and is told what to write to disk
-           and what command to run. This is cross-compiled to all architectures
+           and what command to run. This is cross-compiled to different architectures
            and is the first program run when a builder VM comes up. It then
-           is contacted by the coordinator to do a build.
+           is contacted by the coordinator to do a build. Not all builders use
-builder/: gobuilder, a Go continuous build client
+           the buildlet (at least not yet).
+builder/: gobuilder, a Go continuous build client. The original Go builder program.
 coordinator/: daemon that runs on CoreOS on Google Compute Engine and manages
-          builds (using the builder in single-shot mode) in Docker containers.
+          builds using Docker containers and/or VMs as needed.
-env/:     configuration files describing the environment of builders and related binaries.
+env/:     configuration files describing the environment of builders and related
-          Many builders are still configured ad-hoc.
+          binaries. Many builders are still configured ad-hoc, without a hermetic
+          environment.
+retrybuilds/: a Go client program to delete build results from the dashboard (app)
+types/:   a Go package contain common types used by other pieces.
 watcher/: a daemon that watches for new commits to the Go repository and
           its sub-repositories, and notifies the dashboard of those commits.
 
-If you wish to run a Go builder, please email golang-dev@googlegroups.com
+If you wish to run a Go builder, please email golang-dev@googlegroups.com first.
+There is documentation at https://golang.org/wiki/DashboardBuilders but
+depending on the type of builder, we may want to run it ourselves, after you
+prepare an environment description (resulting in a VM image) of it. See the env
+directory.
 
-To run a builder:
-
-* Write the key ~gobuild/.gobuildkey 
-  You need to get it from someone who knows the key.
-  You may also use a filename of the form .gobuildkey-$BUILDER if you
-  wish to run builders for multiple targets.
-
-* Append your username and password googlecode.com credentials from
-    https://code.google.com/hosting/settings
-  to the buildkey file in the format "Username\nPassword\n".
-  (This is for uploading tarballs to the project downloads section,
-   and is an optional step.)
-
-* Build and run gobuilder (see its documentation for command-line options).
 

dashboard/app/build/ui.go

@@ -11,6 +11,7 @@ package build
 
 import (
 	"bytes"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"html/template"
@@ -20,6 +21,8 @@ import (
 	"strconv"
 	"strings"
 
+	"golang.org/x/tools/dashboard/types"
+
 	"cache"
 
 	"appengine"
@@ -95,9 +98,13 @@ func uiHandler(w http.ResponseWriter, r *http.Request) {
 	}
 	data := &uiTemplateData{d, pkg, commits, builders, tipState, p, branch}
 
-	if r.FormValue("mode") == "failures" {
+	switch r.FormValue("mode") {
+	case "failures":
 		failuresHandler(w, r, data)
 		return
+	case "json":
+		jsonHandler(w, r, data)
+		return
 	}
 
 	var buf bytes.Buffer
@@ -129,6 +136,62 @@ func failuresHandler(w http.ResponseWriter, r *http.Request, data *uiTemplateDat
 	}
 }
 
+// jsonHandler is https://build.golang.org/?mode=json
+// The output is a types.BuildStatus JSON object.
+func jsonHandler(w http.ResponseWriter, r *http.Request, data *uiTemplateData) {
+	d := dashboardForRequest(r)
+
+	// cell returns one of "" (no data), "ok", or a failure URL.
+	cell := func(res *Result) string {
+		switch {
+		case res == nil:
+			return ""
+		case res.OK:
+			return "ok"
+		}
+		return fmt.Sprintf("https://%v%v/log/%v", r.Host, d.Prefix, res.LogHash)
+	}
+
+	var res types.BuildStatus
+	res.Builders = data.Builders
+
+	// First the commits from the main section (the "go" repo)
+	for _, c := range data.Commits {
+		rev := types.BuildRevision{
+			Repo:     "go",
+			Revision: c.Hash,
+			Results:  make([]string, len(data.Builders)),
+		}
+		for i, b := range data.Builders {
+			rev.Results[i] = cell(c.Result(b, ""))
+		}
+		res.Revisions = append(res.Revisions, rev)
+	}
+
+	// Then the one commit each for the subrepos.
+	// TODO(bradfitz): we'll probably want more than one later, for people looking at
+	// the subrepo-specific build history pages. But for now this gets me some data
+	// to make forward progress.
+	tip := data.TipState // a TagState
+	for _, pkgState := range tip.Packages {
+		goRev := tip.Tag.Hash
+		rev := types.BuildRevision{
+			Repo:       pkgState.Package.Name,
+			Revision:   pkgState.Commit.Hash,
+			GoRevision: goRev,
+			Results:    make([]string, len(data.Builders)),
+		}
+		for i, b := range res.Builders {
+			rev.Results[i] = cell(pkgState.Commit.Result(b, goRev))
+		}
+		res.Revisions = append(res.Revisions, rev)
+	}
+
+	v, _ := json.MarshalIndent(res, "", "\t")
+	w.Header().Set("Content-Type", "text/json; charset=utf-8")
+	w.Write(v)
+}
+
 type Pagination struct {
 	Next, Prev int
 	HasPrev    bool

dashboard/types/types.go

@@ -0,0 +1,40 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package types contains common types used by the Go continuous build
+// system.
+package types
+
+// BuildStatus is the data structure that's marshalled as JSON
+// for the http://build.golang.org/?mode=json page.
+type BuildStatus struct {
+	// Builders is a list of all known builders.
+	// The order that builders appear is the same order as the build results for a revision.
+	Builders []string `json:"builders"`
+
+	// Revisions are the revisions shown on the front page of build.golang.org,
+	// in the same order. It starts with the "go" repo, from recent to old, and then
+	// it has 1 each of the subrepos, with only their most recent commit.
+	Revisions []BuildRevision `json:"revisions"`
+}
+
+// BuildRevision is the status of a commit across all builders.
+// It corresponds to a single row of http://build.golang.org/
+type BuildRevision struct {
+	// Repo is "go" for the main repo, else  "tools", "crypto", "net", etc.
+	// These are repos as listed at https://go.googlesource.com/
+	Repo string `json:"repo"`
+
+	// Revision is the full git hash of the repo.
+	Revision string `json:"revision"`
+
+	// GoRevision is the full git hash of the "go" repo, if Repo is not "go" itself.
+	// Otherwise this is empty.
+	GoRevision string `json:"goRevision,omitempty"`
+
+	// Results are the build results for each of the builders in
+	// the same length slice BuildStatus.Builders.
+	// Each string is either "" (if no data), "ok", or the URL to failure logs.
+	Results []string `json:"results"`
+}