xref: /aosp_15_r20/external/spdx-tools/examples/2-load-save/example_load_save.go (revision ba677afa8f67bb56cbc794f4d0e378e0da058e16)
1// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
2
3// Example for: *tvloader*, *tvsaver*
4
5// This example demonstrates loading an SPDX tag-value file from disk into memory,
6// and re-saving it to a different file on disk.
7// Run project: go run example_load_save.go ../sample-docs/tv/hello.spdx test.spdx
8
9package main
10
11import (
12	"fmt"
13	"os"
14
15	"github.com/spdx/tools-golang/tvloader"
16	"github.com/spdx/tools-golang/tvsaver"
17)
18
19func main() {
20
21	// check that we've received the right number of arguments
22	args := os.Args
23	if len(args) != 3 {
24		fmt.Printf("Usage: %v <spdx-file-in> <spdx-file-out>\n", args[0])
25		fmt.Printf("  Load SPDX 2.2 tag-value file <spdx-file-in>, and\n")
26		fmt.Printf("  save it out to <spdx-file-out>.\n")
27		return
28	}
29
30	// open the SPDX file
31	fileIn := args[1]
32	r, err := os.Open(fileIn)
33	if err != nil {
34		fmt.Printf("Error while opening %v for reading: %v", fileIn, err)
35		return
36	}
37	defer r.Close()
38
39	// try to load the SPDX file's contents as a tag-value file, version 2.2
40	doc, err := tvloader.Load2_2(r)
41	if err != nil {
42		fmt.Printf("Error while parsing %v: %v", fileIn, err)
43		return
44	}
45
46	// if we got here, the file is now loaded into memory.
47	fmt.Printf("Successfully loaded %s\n", fileIn)
48
49	// we can now save it back to disk, using tvsaver.
50
51	// create a new file for writing
52	fileOut := args[2]
53	w, err := os.Create(fileOut)
54	if err != nil {
55		fmt.Printf("Error while opening %v for writing: %v", fileOut, err)
56		return
57	}
58	defer w.Close()
59
60	// try to save the document to disk as an SPDX tag-value file, version 2.2
61	err = tvsaver.Save2_2(doc, w)
62	if err != nil {
63		fmt.Printf("Error while saving %v: %v", fileOut, err)
64		return
65	}
66
67	// it worked
68	fmt.Printf("Successfully saved %s\n", fileOut)
69}
70