Difference between revisions of "IoTGateway/AdvJSON"

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−
=What is JSON?=
+
= What is JSON? =
−
=C functions=
+
 
−
=AdvJSON=
+
*JSON stands for JavaScript Object Notation
−
==Fundamental==
+
*JSON is a lightweight data-interchange format
−
==Erase & Delete==
+
*JSON is language independent
−
==Operation==
+
*JSON is "self-describing" and easy to understand
−
==Creator==
+
 
−
==Example==
+
= C functions =
 +
 
 +
== List ==
 +
 
 +
 
 +
<syntaxhighlight lang="C">int JSON_Validator(const char *json);</syntaxhighlight>''Description''
 +
*This function validates a string in JSON format.
 +
 
 +
''Parameters''
 +
 
 +
*json [POINTER]
 +
 
 +
::a string.
 +
 
 +
''Return Values''
 +
 
 +
*[0|1] Error or Success.
 +
 
 +
 
 +
 
 +
----
 +
 
 +
 
 +
<br/><syntaxhighlight lang="C">JSONode *JSON_Parser(const char *json);</syntaxhighlight> ''Description''
 +
*Translate a string into a tree structure pointer(JSONode);
 +
 
 +
''Parameters''
 +
 
 +
*json [POINTER]
 +
 
 +
::a string.
 +
 
 +
''Return Values''
 +
 
 +
*(JSONode *)
 +
 
 +
::A pointer describes a JSON tree structure.
 +
 
 +
 
 +
 
 +
----
 +
 
 +
 
 +
<br/><syntaxhighlight lang="C">void JSON_Destory(JSONode **json);</syntaxhighlight> ''Description''
 +
*Destory a JSON tree sturcture;
 +
 
 +
''Parameters''
 +
 
 +
*json [POINTER]
 +
 
 +
::double-pointer of JSON tree sturcture.
 +
 
 +
''Return Values''
 +
 
 +
*None
 +
 
 +
 
 +
 
 +
----
 +
 
 +
 
 +
<br/><syntaxhighlight lang="C">JSONode *JSON_Copy(JSONode *json);</syntaxhighlight> ''Description''
 +
*Copy a JSON tree sturcture into another pointer.
 +
 
 +
''Parameters''
 +
 
 +
*json [POINTER]
 +
 
 +
::source pointer
 +
 
 +
''Return Values''
 +
 
 +
*(JSONode *)
 +
 
 +
::result pointer
 +
 
 +
 
 +
 
 +
----
 +
 
 +
 
 +
<br/><syntaxhighlight lang="C">void JSON_Get(JSONode *json, const char *path, char *result, int size);</syntaxhighlight> ''Description''
 +
*A Structured-Path-Query function.
 +
 
 +
''Parameters''
 +
 
 +
*json [POINTER]
 +
 
 +
::source.
 +
 
 +
*path [POINTER]
 +
 
 +
::a structure-path string
 +
 
 +
*result [POINTER]
 +
 
 +
::result string
 +
 
 +
*size [NUMBER]
 +
 
 +
::the size of result.
 +
 
 +
''Return Values''
 +
 
 +
*None
 +
 
 +
''Example''
 +
<syntaxhighlight lang="C">
 +
char result[256];
 +
JSON_Get(json, "[a][b][c][d]", result, 256);
 +
JSON_Get(json, "/a/b/c/d", result, 256);
 +
</syntaxhighlight><br/>
 +
----
 +
 
 +
 
 +
<br/><syntaxhighlight lang="C">void JSON_Cmd(JSONode *json, const char *path, char *assign, int size);</syntaxhighlight> ''Description''
 +
*A Command-line-like function.
 +
 
 +
''Parameters''
 +
 
 +
*json [POINTER]
 +
 
 +
::source.
 +
 
 +
*path [POINTER]
 +
 
 +
::a command string
 +
:::*Get or GET: for getting the value of element
 +
:::*New or POST: for creating a new element
 +
:::*Edit or PUT: for editing the value of element
 +
:::*Delete or DELETE: for deleting a element
 +
:::P.S. All upper case is REST style.
 +
*assign[POINTER]
 +
 
 +
::target
 +
 
 +
*size [NUMBER]
 +
 
 +
::the size of target.
 +
 
 +
''Return Values''
 +
 
 +
*None
 +
 
 +
''Example''
 +
<syntaxhighlight lang="C">
 +
JSON_Cmd(json, "New [a][b][c][d]", "123", 3);
 +
JSON_Cmd(json, "POST /a/b/c/d", "123", 3);
 +
</syntaxhighlight>
 +
= C++ =
 +
 
 +
== Fundamental ==
 +
 
 +
*Read only
 +
 
 +
::name = movie[“name”].String();
 +
::<font color="red">movie[“name”] = “After Tomorrow”; </font> <font color="green">//Error, Read only</font>
 +
 
 +
*Edit
 +
 
 +
::movie.Edit()[“name”] = “After Tomorrow”; <font color="green">//Edit 'Value'</font>
 +
::movie.Edit()[“name”] << “Name”; <font color="green">//Edit 'Key'</font>
 +
::<font color="red">movie.Edit()[“Year”] = 2004; </font> <font color="green">//Error, Can't create new element</font>
 +
 
 +
*New
 +
 
 +
::movie.New()[“Year”] = 2004; <font color="green">//Create a new element</font>
 +
 
 +
*Erase
 +
 
 +
::movie[“Year”].Erase();
 +
 
 +
*Delete
 +
 
 +
::movie[“Year”].Delete();
 +
 
 +
== Erase & Delete ==
 +
 
 +
<big>'''Example:'''</big><br/>AdvJSON json("{}");<br/>json.New()["number"] = {1,2,3,4,5,6,7,8,9,10};<br/>'''result:'''
 +
 
 +
{"number":[1,2,3,4,5,6,7,8,9,10]}
 +
 
 +
*Erase
 +
 
 +
json["number"][5].Erase();<br/>'''result:'''
 +
 
 +
{"number":[1,2,3,4,5,null,7,8,9,10]}
 +
 
 +
*Delete
 +
 
 +
json["number"][3].Delete();<br/>'''result:'''
 +
 
 +
{"number":[1,2,3,5,null,7,8,9,10]}
 +
 
 +
== Operation ==
 +
 
 +
=== Indicator ===
 +
 
 +
Using Array operator to access the JSON tree.<br/><big>'''Example:'''</big>
 +
 
 +
movie[“format”][“type”]
 +
movie[“format”][“frame rate”][0]
 +
 
 +
=== Array ===
 +
 
 +
<big>'''Example:'''</big>
 +
 
 +
movie.Edit()[“format”][“frame rate”] = {8,16,32};
 +
movie.New()[“format”][“frame rate”] += {64,128,256};
 +
movie.New()[“format”][“resolution”] = { {720,480}, {1920,1080}, {4096,2160} };
 +
 
 +
=== Parallel ===
 +
 
 +
[<font color="red">{ , , , }</font>] = <font color="red">{ , , , }</font><br/><big>'''Example:'''</big><br/>AdvJSON movie("{}");
 +
 
 +
movie.New()[{"name",          "width", "height", "frame rate"}] =
 +
            {"Jurassic World", 1920,    1080,    {15, 25, 30}};
 +
 
 +
'''Result:'''
 +
 
 +
{
 +
    "name":      "Jurassic World",
 +
    "width":      1920,
 +
    "height":    1080,
 +
    "frame rate": {15, 25, 30}
 +
}
 +
 
 +
== Creator ==
 +
 
 +
C[ <font color="red">{ , , , }</font> ]( <font color="red">{ , , , }</font> )<br/><big>'''Example:'''</big>
 +
 
 +
AdvJSON movie("{}");
 +
movie.New()[{"name",          "width", "height", "frame rate"}] =
 +
            {"Jurassic World",  1920,    1080,    {15, 25, 30}};
 +
 
 +
movie.New()["info"] = C[{  "video"    ,    "audio"    }]({
 +
                        {"H264","6000"} , {"AAC", "14400"}});
 +
 
 +
'''Result:'''
 +
 
 +
{
 +
    "name":      "Jurassic World",
 +
    "width":      1920,
 +
    "height":    1080,
 +
    "frame rate": {15, 25, 30}
 +
    "info": {
 +
        "video": ["H264","6000"],
 +
        "audio": ["AAC", "14400"]
 +
    }
 +
}
 +
 
 +
== Example ==
 +
 
 +
AdvJSON iot("{}");
 +
AdvJSONCreator C(iot);
 +
iot.New()["IoTGW"]["WSN"]["WSN0"][{"Info","bn","ver"}] = {
 +
    C[{"e","bn"}]({
 +
        {
 +
            C[{"n","sv","asm"}]({"SenHubList","0000000EC6F0F830,0000000EC6F0F831","r"}),
 +
            C[{"n","sv","asm"}]({"Neighbor","0000000EC6F0F830","r"}),
 +
            C[{"n","v","asm"}]({"Health",80,"r"}),
 +
            C[{"n","sv","asm"}]({"Name","WSN0","r"}),
 +
            C[{"n","sv","asm"}]({"sw","1.0.0.1","r"}),
 +
            C[{"n","bv","asm"}]({"reset",0,"rw"}),
 +
        },
 +
        "Info"
 +
    }),
 +
    "0000852CF4B7B0E8",
 +
    1
 +
};
 +
 
 +
'''Result:'''
 +
 
 +
{
 +
    "IoTGW": {
 +
        "WSN: {
 +
            "WSN0": {
 +
                "Info": {
 +
                    "e": [
 +
                        { "n": "SenHubList", "sv": "0000000EC6F0F830,0000000EC6F0F831", "asm": "r"},
 +
                        { "n": "Neighbor",  "sv": "0000000EC6F0F830",                  "asm": "r"},
 +
                        { "n": "Health",    "v": 80,                                  "asm": "r"},
 +
                        { "n": "Name",      "sv": "WSN0",                              "asm": "r"},
 +
                        { "n": "sw",        "sv": "1.0.0.1",                          "asm": "r"},
 +
                        { "n": "reset",      "bv": 0,                                  "asm": "rw"},
 +
                    ],
 +
                    "bn": "Info"
 +
                },
 +
                "bn": "0000852CF4B7B0E8",
 +
                "ver": 1
 +
            }
 +
        }
 +
    }
 +
}

Latest revision as of 04:17, 19 November 2018

What is JSON?

  • JSON stands for JavaScript Object Notation
  • JSON is a lightweight data-interchange format
  • JSON is language independent
  • JSON is "self-describing" and easy to understand

C functions

List

int JSON_Validator(const char *json);
Description
  • This function validates a string in JSON format.

Parameters

  • json [POINTER]
a string.

Return Values

  • [0|1] Error or Success.




JSONode *JSON_Parser(const char *json);
Description
  • Translate a string into a tree structure pointer(JSONode);

Parameters

  • json [POINTER]
a string.

Return Values

  • (JSONode *)
A pointer describes a JSON tree structure.




void JSON_Destory(JSONode **json);
Description
  • Destory a JSON tree sturcture;

Parameters

  • json [POINTER]
double-pointer of JSON tree sturcture.

Return Values

  • None




JSONode *JSON_Copy(JSONode *json);
Description
  • Copy a JSON tree sturcture into another pointer.

Parameters

  • json [POINTER]
source pointer

Return Values

  • (JSONode *)
result pointer




void JSON_Get(JSONode *json, const char *path, char *result, int size);
Description
  • A Structured-Path-Query function.

Parameters

  • json [POINTER]
source.
  • path [POINTER]
a structure-path string
  • result [POINTER]
result string
  • size [NUMBER]
the size of result.

Return Values

  • None

Example 

char result[256];
JSON_Get(json, "[a][b][c][d]", result, 256);
JSON_Get(json, "/a/b/c/d", result, 256);




void JSON_Cmd(JSONode *json, const char *path, char *assign, int size);
Description
  • A Command-line-like function.

Parameters

  • json [POINTER]
source.
  • path [POINTER]
a command string
  • Get or GET: for getting the value of element
  • New or POST: for creating a new element
  • Edit or PUT: for editing the value of element
  • Delete or DELETE: for deleting a element
P.S. All upper case is REST style.
  • assign[POINTER]
target
  • size [NUMBER]
the size of target.

Return Values

  • None

Example 

JSON_Cmd(json, "New [a][b][c][d]", "123", 3);
JSON_Cmd(json, "POST /a/b/c/d", "123", 3);

C++

Fundamental

  • Read only
name = movie[“name”].String();
movie[“name”] = “After Tomorrow”; //Error, Read only
  • Edit
movie.Edit()[“name”] = “After Tomorrow”; //Edit 'Value'
movie.Edit()[“name”] << “Name”; //Edit 'Key'
movie.Edit()[“Year”] = 2004; //Error, Can't create new element
  • New
movie.New()[“Year”] = 2004; //Create a new element
  • Erase
movie[“Year”].Erase();
  • Delete
movie[“Year”].Delete();

Erase & Delete

Example:
AdvJSON json("{}");
json.New()["number"] = {1,2,3,4,5,6,7,8,9,10};
result: 

{"number":[1,2,3,4,5,6,7,8,9,10]}
  • Erase

json["number"][5].Erase();
result: 

{"number":[1,2,3,4,5,null,7,8,9,10]}
  • Delete

json["number"][3].Delete();
result: 

{"number":[1,2,3,5,null,7,8,9,10]}

Operation

Indicator

Using Array operator to access the JSON tree.
Example: 

movie[“format”][“type”]
movie[“format”][“frame rate”][0]

Array

Example: 

movie.Edit()[“format”][“frame rate”] = {8,16,32};
movie.New()[“format”][“frame rate”] += {64,128,256};
movie.New()[“format”][“resolution”] = { {720,480}, {1920,1080}, {4096,2160} };

Parallel

[{ , , , }] = { , , , }
Example:
AdvJSON movie("{}"); 

movie.New()[{"name",           "width", "height", "frame rate"}] =
            {"Jurassic World", 1920,    1080,     {15, 25, 30}};

Result: 

{
    "name":       "Jurassic World",
    "width":      1920,
    "height":     1080,
    "frame rate": {15, 25, 30}
}

Creator

C[ { , , , } ]( { , , , } )
Example: 

AdvJSON movie("{}");
movie.New()[{"name",           "width", "height", "frame rate"}] =
            {"Jurassic World",  1920,    1080,    {15, 25, 30}};

movie.New()["info"] = C[{   "video"     ,     "audio"     }]({
                        {"H264","6000"} , {"AAC", "14400"}});

Result: 

{
    "name":       "Jurassic World",
    "width":      1920,
    "height":     1080,
    "frame rate": {15, 25, 30}
    "info": {
        "video": ["H264","6000"],
        "audio": ["AAC", "14400"]
    }
}

Example

AdvJSON iot("{}");
AdvJSONCreator C(iot);								
iot.New()["IoTGW"]["WSN"]["WSN0"][{"Info","bn","ver"}] = {
    C[{"e","bn"}]({
        {
            C[{"n","sv","asm"}]({"SenHubList","0000000EC6F0F830,0000000EC6F0F831","r"}),
            C[{"n","sv","asm"}]({"Neighbor","0000000EC6F0F830","r"}),
            C[{"n","v","asm"}]({"Health",80,"r"}),
            C[{"n","sv","asm"}]({"Name","WSN0","r"}),
            C[{"n","sv","asm"}]({"sw","1.0.0.1","r"}),
            C[{"n","bv","asm"}]({"reset",0,"rw"}),
        },
        "Info"
    }),
    "0000852CF4B7B0E8",
    1
};

Result: 

{
    "IoTGW": {
        "WSN: {
            "WSN0": {
                "Info": {
                    "e": [
                        { "n": "SenHubList", "sv": "0000000EC6F0F830,0000000EC6F0F831", "asm": "r"},
                        { "n": "Neighbor",   "sv": "0000000EC6F0F830",                  "asm": "r"},
                        { "n": "Health",     "v": 80,                                   "asm": "r"},
                        { "n": "Name",       "sv": "WSN0",                              "asm": "r"},
                        { "n": "sw",         "sv": "1.0.0.1",                           "asm": "r"},
                        { "n": "reset",      "bv": 0,                                   "asm": "rw"},
                    ],
                    "bn": "Info"
                },
                "bn": "0000852CF4B7B0E8",
                "ver": 1
            }
        }
    }
}
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