Lookup Mapping¶

The Lookup Mapping node finds the mapping relationship as per the given CSV mapping file and output the specified mapping data to msg.

To aggregate multiple values, the CSV file must have a column with dataType header name where data in the input msg will be displayed in the output msg according to the specified dataType in the CSV if mapping is successful.

Note

The node is only for querying the mapping relationship. The structuring of the subsequent standard device measurement points would require other nodes.

Node Type¶

IoT Hub.

Input and Output Ability¶

This node has 1 entry point and 1 exit point. Both the input and output are JSON.

Node Properties¶

Name

The name for this node.

Mapping File

Upload the CSV mapping file here. You can click the Download Template icon to download a template to use, click the Upload icon upload to upload the file, or click the Download icon to download the file that has been uploaded.

Mapping Results

Choose from the list of column headers, taken from the mapping file, to set as the output after mapping. You can choose more than one.

The CSV file must have a column with dataType header name if the aggregation of multiple values is required. Available dataType values are as per the below.

number: numeric
string: text
array<number>: numeric array
array<string>: string array
boolean

Mapping Key

Choose from the list of column headers, taken from the mapping file, to set as the mapping key. You can choose more than one.

Mapping Value

By default, data in the input msg will be output to the output msg according to the dataType if mapping is successful (see Sample 1). To output a particular data, specify it using expression, for example ${msg.value} (see Sample 5). Data not specified will not be in the output msg.

Description

The description for this node.

Limitations¶

Maximum number of records in mapping file: 50,000
Maximum mapping file size: 2M
Currently can only upload CSV files as the mapping file.
Can only specify 1 value for Mapping Value.

Samples¶

The samples below are based on a CSV file with the following data.

Key1	Key2	Key3	dataType
AI000001	1KaobBq4I	AO-BOOL-ARRAY	array<string>
AI000001	2KaobBq4I	AO-BOOL-STRING	string
AI000001	3KaobBq4I	AO-BOOL-STRING2	string
AI000001	4KaobBq4I	AO-BOOL-ARRAY	array<string>
AI000002	1KaobBq4I	AO-BOOL-ARRAY	array<string>
AI000002	6KaobBq4I	AO-BOOL-STRING	string
AI000003	7KaobBq4I	AO-BOOL-ARRAY	array<string>
AI000004	8KaobBq4I	AO-BOOL-FLOAT	number

Input and Output Samples¶

Sample 1 ¶

Mapping Results: Key2, Key3

Mapping Key: Key1

Input¶

[
  {
    "Key1": "AI000003", //Key1 is the mapping key
    "value": "88",
    "color": "blue",
    "type": "circle",
  }
]

Output¶

[
  {
    "Key1": "AI000003",
    "value": "88",
    "color": "blue",
    "type": "circle",
    "Key2": "7KaobBq4I",
    "Key3": "AO-BOOL-ARRAY"
  }
]

Sample 2¶

Mapping Results: Key3

Mapping Key: Key1, Key2

Input¶

[
  {
    "Key1": "AI000004", //Key1 and Key2 are the mapping keys
    "Key2": "8KaobBq4I",
    "value": "77"
  }
]

Output¶

[
  {
    "Key1": "AI000004",
    "Key2": "8KaobBq4I",
    "value": "77",
    "Key3": "AO-BOOL-FLOAT"
  }
]

Sample 3¶

Mapping Results: Key2, Key3

Mapping Key: Key1

Mapping Value: ${msg.value}

Input¶

[
  {
    "Key1": "AI000001",
    "value": "5"
  },
  {
    "Key1": "AI000002",
    "value": "6"
  }
]

Output¶

[
  {
    "Key2": "6KaobBq4I",
    "Key1": "AI000002",
    "value": "6",
    "Key3": "AO-BOOL-STRING"
  },
  {
    "Key2": "2KaobBq4I",
    "Key1": "AI000001",
    "value": "5",
    "Key3": "AO-BOOL-STRING"
  },
  {
    "Key2": "3KaobBq4I",
    "Key1": "AI000001",
    "value": "5",
    "Key3": "AO-BOOL-STRING2"
  },
  {
    "Key2": "4KaobBq4I",
    "value": [
      "5"
    ],
    "Key3": "AO-BOOL-FLOAT"
  },
  {
    "Key2": "1KaobBq4I",
    "value": [
      "6",
      "5"
    ],
    "Key3": "AO-BOOL-ARRAY"
  }
]

Sample 4¶

Mapping Results: Key2, Key3

Mapping Key: Key1

Input¶

[
  {
    "Key1": "AI000001",
    "value": "18"
  }
]

Output¶

[
  {
    "Key2": "1KaobBq4I",
    "Key1": "AI000001",
    "value": "18",
    "Key3": "AO-BOOL-ARRAY"
  },
  {
    "Key2": "2KaobBq4I",
    "Key1": "AI000001",
    "value": "18",
    "Key3": "AO-BOOL-STRING"
  },
  {
    "Key2": "3KaobBq4I",
    "Key1": "AI000001",
    "value": "18",
    "Key3": "AO-BOOL-STRING2"
  },
  {
    "Key2": "4KaobBq4I",
    "Key1": "AI000001",
    "value": "18",
    "Key3": "AO-BOOL-ARRAY"
  }
]

Sample 5 ¶

Mapping Results: Key2, Key3

Mapping Key: Key1

Mapping Value: ${msg.color}

Input¶

[
  {
    "Key1": "AI000003",
    "value": "7",
    "color": "blue",
    "type": "circle"
  }
]

Output¶

[
  {
      "Key2": "7KaobBq4I",
      "color": [
        "blue"
      ],
      "Key3": "AO-BOOL-ARRAY"
    }
]