LibMISB - Examples - Library basic usage

Testing library

This library has an example that you can execute. This example is a metadata converter that can encode or decode metadata. If you want to encode, the input file must respect one of the supported formats and will return a binary file with metadata encoded. On the other hand, if you want to decode the program receives a binary file and converts it to the format file selected. Currently JSON format is supported for the input and output encoding files.

The executable is located on /misb-library/examples/misb/ or if you want to compile and execute the example file out of the project. The path of the example is located on /misb-library/examples/misb/misb-converter.cpp. To compile the example we suggest you follow the next Makefile:

FLAGS:=`pkg-config --cflags --libs misb-0.0`
misb-converter: misb-converter.cpp
	g++ -o misb-converter misb-converter.cpp $(FLAGS)

The input JSON file that is going to be used is as follows:

{ 
  "key": "060E2B34020B01010E01030101000000",
  "items": [
    {
      "tag": "2",
      "value": "Oct. 24, 2008. 00:13:29.913"
    },
    {
      "tag": "3",
      "value": "MISSION01"
    },
    {
      "tag": "4",
      "value": "AF-101"
    },
    {
      "tag": "5",
      "value": "159.97436"
    },
    {
      "tag": "15",
      "value": "14190.7195"
    }
  ]
}

Or alternitevly if you want to use the 0903 standard:

{ 
    "key": "060E2B34020B01010E01030306000000",
    "items": [
      {
        "tag": "2",
        "value": "Apr. 19, 2001. 04:25:21.000"
      },
      {
          "tag": "101",
          "value": [
            {
              "tag": "targetId",
              "value": "1234"
            },
            {
              "tag": "1",
              "value": "409600"
            },
            {
              "tag": "3",
              "value": "409600"
            },
            {
              "tag": "5",
              "value": "80"
            },
            {
              "tag": "targetId",
              "value": "1235"
            },
            {
              "tag": "1",
              "value": "409601"
            },
            {
              "tag": "3",
              "value": "409601"
            }
          ]
      },
      {
        "tag": "6",
        "value": "2"
      }
    ]
  }

The following command is executed to perform the encoding. The--encode flag indicates that encoding is to be performed. The -i flag indicates the input file, where the metadata must be raw without encoding. On the other hand, the -o flag indicates the output file, which contains the encoded bytes in a binary file. The --verbose flag shows the KLV bytes encoded on the terminal.

./misb-converter --verbose --encode -i misb_ST0601_sample.json -o klv.bin

or

./misb-converter --verbose --encode -i misb_ST0903_sample.json -o klv.bin

Once the command is executed (with the --verbose flag), the KLV bytes are displayed. The 0601 klv.bin file contains the encoded bytes.

INFO    6 14 43 52 2 11 1 1 14 1 3 1 1 0 0 0 44 2 8 0 4 89 249 174 32 34 168 3 9 77 73 83 83 73 79 78 48 49 4 6 65 70 45 49 48 49 5 2 113 194 15 2 194 33 65 1 17 1 2 164 125

Decode command

The following command is executed to perform the decoding. The --decode flag indicates that decoding is to be performed. The -i flag indicates the input file, where the metadata must be encoded. The -o flag indicates the output file containing the decoded metadata.

The encoded bytes found inside the 0601 klv.bin file are:

6 14 43 52 2 11 1 1 14 1 3 1 1 0 0 0 44 2 8 0 
4 89 249 174 32 34 168 3 9 77 73 83 83 73 79 
78 48 49 4 6 65 70 45 49 48 49 5 2 113 194 15 
2 194 33 65 1 17 1 2 164 125

./misb-converter --decode -i klv.bin -o output.json

Once the command is executed, it reports that a decoded file was generated. The content of the output.json file is

{
  "key": "060E2B34020B01010E01030101000000",
  "items": [
    {
      "tag": "2",
      "value": "Oct. 24, 2008. 00:13:29.913"
    },
    {
      "tag": "3",
      "value": "MISSION01"
    },
    {
      "tag": "4",
      "value": "AF-101"
    },
    {
      "tag": "5",
      "value": "159.974365"
    },
    {
      "tag": "15",
      "value": "14190.719463"
    },
    {
      "tag": "65",
      "value": "17"
    }
  ]
}

and for the 0903:

{
  "key": "060E2B34020B01010E01030306000000",
  "items": [
    {
      "tag": "2",
      "value": "Apr. 19, 2001. 04:25:21.000"
    },
    {
      "tag": "101",
      "value": [
        {
          "tag": "id",
          "value": "1234"
        },
        {
          "tag": "1",
          "value": "409600"
        },
        {
          "tag": "3",
          "value": "409600"
        },
        {
          "tag": "5",
          "value": "80"
        },
        {
          "tag": "id",
          "value": "1235"
        },
        {
          "tag": "1",
          "value": "409601"
        },
        {
          "tag": "3",
          "value": "409601"
        }
      ]
    },
    {
      "tag": "6",
      "value": "2"
    },
    {
      "tag": "4",
      "value": "6"
    }
  ]
}
<syntaxhighlight lang=json>

As seen here some extra flags can be present after the decoding process since the encoding might add required tags to the encoding.

== Logging ==

You can enable the debugging using '''SetLogLevel''' in your application with the LibMISB. For example:

<syntaxhighlight lang=cpp>
  libmisb::LibMisb libmisb;
  libmisb.SetLogLevel(LIBMISB_DEBUG);