Refactor GoVPP

Squashed commit of the following:

commit 348930db31575e9f59b3834d9fec07411f011e05
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Wed Aug 15 11:30:13 2018 +0200

    Use debug level for log about different context

commit 9fc963c559cea67a41b85c6cdadc322fb3b1fc7c
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Wed Aug 15 11:22:03 2018 +0200

    Remove annoying logs and add env vars for debugging

commit fdc9fd624d13feadb602e0d03d58f8a44b7a565f
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Wed Aug 15 11:18:47 2018 +0200

    Fix printing unknown VPPApiError

commit 8f968be36a91de4d4a8ea17593ba314f82aa9583
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Tue Aug 14 17:25:10 2018 +0200

    Refactor entire GoVPP

    - fix some cases with inconsistent VPP messages, causing messages
      to be incorrectly identified as event or request
    - simplify API, remove direct access to internal Go channels
    - add module name with message to registration of messages
    - start watching filesystem only when vpe-api file does not exist
    - simplify code in message codec and remove unneeded parts
    - retrieve IDs of all registered messages after connect to VPP
    - define fallback for control ping in core to avoid duplicate registration
    - add SetLogLevel function to set logger level more easily
    - remove lot of unused code

commit 34dd1b7e10ef0324aa8c4e4cc42375bd6021c6cb
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Mon Aug 13 11:29:54 2018 +0200

    Rename VnetError to VPPApiError

commit c6549d6f77847a1367a12ff47fb716e2955e973a
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Mon Aug 13 10:23:43 2018 +0200

    Fix examples and regenerate binapi

commit 4612e36b416779771f5efab4fc654c2766d2cb1c
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Mon Aug 13 09:51:22 2018 +0200

    Add parsing and generation for services

commit ac9c5280c5aa27e325f327609e2364cc66f3723f
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Fri Aug 10 14:30:15 2018 +0200

    Fix exit status on error and add continue-onerror flag

commit 9b3f4ef9fc7c8c62037fa107085eae18a8725314
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 15:20:56 2018 +0200

    Return VnetError when Retval != 0

commit 8fd21a907b5e628ec4d2026215b83d15da96c297
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 14:59:05 2018 +0200

    Add all missing errors from api_errno.h

commit 08450f288d3046ebaecf40203174ae342a07f1eb
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 14:29:27 2018 +0200

    Update README

commit d8dced0728dd62243539be741868fb7d9b8de4cc
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 13:59:59 2018 +0200

    Regenerate vpe in core

commit 254da7592cdbf634cf7aa46ae36ce7bb6d4ee555
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 13:37:00 2018 +0200

    Add VnetError type for Retvals

commit 4475c1087fb53ab4c788e530bc7fef7cfc89d2cd
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 13:36:07 2018 +0200

    Add registration API

commit 892a3ea5a2c703e2f7c29331663f6a6fa706bff5
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 13:30:43 2018 +0200

    Generate registration for messages and check all IDs on connect

commit 389ed03b6e7082260281866c3449d72d72347c99
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 11:32:41 2018 +0200

    Show error for empty adapter (on Darwin/Windows)

commit ef1ea040d656ade64242432dc5f06810ed8dcde6
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 11:31:37 2018 +0200

    Improve logged info

commit d4adae3b14ed54c8d693060dd857fa9ba5ec8e06
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 11:27:48 2018 +0200

    Update examples

commit 63921e1346014701a22639a2611129563bb1eb78
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Thu Aug 9 11:02:56 2018 +0200

    Generate unions and fix some issues

    - add comments between sections
    - define structs on single line if it has no fields
    - generate unions with setters/getters for each field
    - fix detection of message type

commit 6ab3e3fa590b245898306a6ffaf32c7721eab60c
Author: Ondrej Fabry <ofabry@cisco.com>
Date:   Wed Aug 8 15:37:10 2018 +0200

    Refactor binapi-generator

    - split JSON parsing from code generation
    - parse and generate enums
    - parse unions (no generation yet)
    - change output file suffix to '.ba.go'
    - cleanup and simplify code
    - split code into files
    - add flag for debug mode

Change-Id: I58f685e0d4c7a38e9a7b6ea0a1f47792d95d7399
Signed-off-by: Ondrej Fabry <ofabry@cisco.com>

1 files changed, 173 insertions, 0 deletions

diff --git a/cmd/binapi-generator/main.go b/cmd/binapi-generator/main.go
new file mode 100644
index 0000000..8045212
--- /dev/null
+++ b/cmd/binapi-generator/main.go
@@ -0,0 +1,173 @@
+// Copyright (c) 2018 Cisco and/or its affiliates.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at:
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"bufio"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"github.com/bennyscetbun/jsongo"
+)
+
+var (
+	inputFile       = flag.String("input-file", "", "Input JSON file.")
+	inputDir        = flag.String("input-dir", ".", "Input directory with JSON files.")
+	outputDir       = flag.String("output-dir", ".", "Output directory where package folders will be generated.")
+	includeAPIVer   = flag.Bool("include-apiver", false, "Whether to include VlAPIVersion in generated file.")
+	debug           = flag.Bool("debug", false, "Turn on debug mode.")
+	continueOnError = flag.Bool("continue-onerror", false, "Wheter to continue with next file on error.")
+)
+
+func logf(f string, v ...interface{}) {
+	if *debug {
+		log.Printf(f, v...)
+	}
+}
+
+func main() {
+	flag.Parse()
+
+	if *inputFile == "" && *inputDir == "" {
+		fmt.Fprintln(os.Stderr, "ERROR: input-file or input-dir must be specified")
+		os.Exit(1)
+	}
+
+	if *inputFile != "" {
+		// process one input file
+		if err := generateFromFile(*inputFile, *outputDir); err != nil {
+			fmt.Fprintf(os.Stderr, "ERROR: code generation from %s failed: %v\n", *inputFile, err)
+			os.Exit(1)
+		}
+	} else {
+		// process all files in specified directory
+		files, err := getInputFiles(*inputDir)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "ERROR: code generation failed: %v\n", err)
+			os.Exit(1)
+		}
+		for _, file := range files {
+			if err := generateFromFile(file, *outputDir); err != nil {
+				fmt.Fprintf(os.Stderr, "ERROR: code generation from %s failed: %v\n", file, err)
+				if *continueOnError {
+					continue
+				}
+				os.Exit(1)
+			}
+		}
+	}
+}
+
+// getInputFiles returns all input files located in specified directory
+func getInputFiles(inputDir string) (res []string, err error) {
+	files, err := ioutil.ReadDir(inputDir)
+	if err != nil {
+		return nil, fmt.Errorf("reading directory %s failed: %v", inputDir, err)
+	}
+	for _, f := range files {
+		if strings.HasSuffix(f.Name(), inputFileExt) {
+			res = append(res, filepath.Join(inputDir, f.Name()))
+		}
+	}
+	return res, nil
+}
+
+// generateFromFile generates Go package from one input JSON file
+func generateFromFile(inputFile, outputDir string) error {
+	logf("generating from file: %q", inputFile)
+	defer logf("--------------------------------------")
+
+	ctx, err := getContext(inputFile, outputDir)
+	if err != nil {
+		return err
+	}
+
+	// read input file contents
+	ctx.inputData, err = readFile(inputFile)
+	if err != nil {
+		return err
+	}
+	// parse JSON data into objects
+	jsonRoot, err := parseJSON(ctx.inputData)
+	if err != nil {
+		return err
+	}
+	ctx.packageData, err = parsePackage(ctx, jsonRoot)
+	if err != nil {
+		return err
+	}
+
+	// create output directory
+	packageDir := filepath.Dir(ctx.outputFile)
+	if err := os.MkdirAll(packageDir, 0777); err != nil {
+		return fmt.Errorf("creating output directory %q failed: %v", packageDir, err)
+	}
+	// open output file
+	f, err := os.Create(ctx.outputFile)
+	if err != nil {
+		return fmt.Errorf("creating output file %q failed: %v", ctx.outputFile, err)
+	}
+	defer f.Close()
+
+	// generate Go package code
+	w := bufio.NewWriter(f)
+	if err := generatePackage(ctx, w); err != nil {
+		return err
+	}
+
+	// go format the output file (fail probably means the output is not compilable)
+	cmd := exec.Command("gofmt", "-w", ctx.outputFile)
+	if output, err := cmd.CombinedOutput(); err != nil {
+		return fmt.Errorf("gofmt failed: %v\n%s", err, string(output))
+	}
+
+	// count number of lines in generated output file
+	cmd = exec.Command("wc", "-l", ctx.outputFile)
+	if output, err := cmd.CombinedOutput(); err != nil {
+		log.Printf("wc command failed: %v\n%s", err, string(output))
+	} else {
+		logf("generated lines: %s", output)
+	}
+
+	return nil
+}
+
+// readFile reads content of a file into memory
+func readFile(inputFile string) ([]byte, error) {
+	inputData, err := ioutil.ReadFile(inputFile)
+	if err != nil {
+		return nil, fmt.Errorf("reading data from file failed: %v", err)
+	}
+
+	return inputData, nil
+}
+
+// parseJSON parses a JSON data into an in-memory tree
+func parseJSON(inputData []byte) (*jsongo.JSONNode, error) {
+	root := jsongo.JSONNode{}
+
+	if err := json.Unmarshal(inputData, &root); err != nil {
+		return nil, fmt.Errorf("unmarshalling JSON failed: %v", err)
+	}
+
+	return &root, nil
+}