Abstract

Contents

• Meta
• Global Functions
  • _deletePatternRec
  • _getBestMatchRec
  • _getFirstMatchRec
  • _max
  • addPattern
  • deletePattern
  • getBestMatch
  • getFirstMatch
• Class TopicMatch
  • Parameters
  • Members
  • Methods
    • addPattern
    • changePattern
    • clear
    • deletePattern
    • getBestMatch
    • getFirstMatch
    • toJSON

Meta

Global functions

_deletePatternRec

_deletePatternRec (topicChunks, node, index)

Recursively removes a pattern ( exact match ) from the tree

_deletePatternRec Parameters

| Name | Type | Attribute | Default | Description | | ---------- | ------------ | ------------ | ------------ | ----------------- | | topicChunks | Array.<string> | | | topic chunks to search for | | | node | Object | | | current node in the pattern tree | | | index | number | optional | 0 | current index ( depth ) in the topic array | |

_getBestMatchRec

_getBestMatchRec (isBetter, topicChunks, node, index)

Searches for a topic in a pattern tree , returns the best match ( match with highest value )

_getBestMatchRec Parameters

| Name | Type | Attribute | Default | Description | | ---------- | ------------ | ------------ | ------------ | ----------------- | | isBetter | function(a, b | | | returns true , if a is better than b | | | topicChunks | Array.<string> | | | topic chunks to search for | | | node | Object | | | current node in the pattern tree | | | index | number | optional | 0 | current index ( depth ) in the topic array | |

_getFirstMatchRec

_getFirstMatchRec (topicChunks, node, index)

Searches for a topic in a pattern tree , returns the first match

_getFirstMatchRec Parameters

| Name | Type | Attribute | Default | Description | | ---------- | ------------ | ------------ | ------------ | ----------------- | | topicChunks | Array.<string> | | | topic chunks to search for | | | node | Object | | | current node in the pattern tree | | | index | number | optional | 0 | current index ( depth ) in the topic array | |

_max

_max (isBetter, a, b)

Gets the maximum of two elements that are either a number or undefined . Undefined values are ignored _max ( undefined , undefined ) = undefined _max ( undefined , b ) = b

_max Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | isBetter | function(a, b | returns true , if a is better than b | | | a | number, undefined | first element | | | b | number, undefined | second element | |

addPattern

addPattern (pattern, value)

Adds a pattern to a pattern tree . The pattern has '/' as separator

addPattern Parameters

| Name | Type | Attribute | Default | Description | | ---------- | ------------ | ------------ | ------------ | ----------------- | | pattern | string | | | pattern string with '/' as separator | | | value | number | optional | 0 | pattern value | |

deletePattern

deletePattern (pattern)

Delete a pattern from the tree

deletePattern Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | pattern | string | pattern to delete | |

getBestMatch

getBestMatch (topic, isBetter)

Gets the first match of a topic

getBestMatch Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | topic | string | topic to search for | | | isBetter | function(a, b | returns true , if a is better than b | |

getFirstMatch

getFirstMatch (topic)

Gets the first match of a topic

getFirstMatch Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | topic | string | topic to search for | |

Class TopicMatch

new TopicMatch(pattern)

Contructs a new class Checks , if a topic matches a list of patterns . The pattern is bases on the MQTT pattern design . Every pattern has an associated value ( used for QoS in MQTT ) Topic structure slashes with strings in between : /string1/string2/string3/ . . . Pattern is like topic with the following whildcards : "+" and "#" . The "+" matches any string , the "#" matches the rest of the topic .

Example

const topicMatch = new TopicMatch()
topicMatch.addPattern('#', 0)
topicMatch.getFirstMatch('hello') // returns 0
topicMatch.removePattern('#')
topicMatch.addPattern('/+', 1)
topicMatch.getFirstMatch('hello') // returns undefined
topicMatch.getFirstMatch('/hello') // returns 1
topicMatch.getFirstMatch('/hello/world') // returns undefined

TopicMatch Parameters

| Name | Type | Attribute | Default | Description | | ---------- | ------------ | ------------ | ------------ | ----------------- | | pattern | Object, Array, string | optional | { } | pattern data structure { pattern : value , pattern : value , . . . } | |

TopicMatch Members

| Name | Type | description | | ------------ | ------------ | ------------ | | topicPatternList | @type | List containing all active pattern { pattern : QoS , . . . } |

TopicMatch Methods

addPattern

addPattern (pattern, value)

Adds a pattern string to the patternlist ( if not already included )

addPattern Parameters

| Name | Type | Attribute | Default | Description | | ---------- | ------------ | ------------ | ------------ | ----------------- | | pattern | string, Array, Object | | | single pattern or list of pattern | | | value | any | optional | 0 | value associated with the pattern | |

addPattern throws

| Type | Description | | ---- | ----------- | | Error | if pattern is not string or value is not provided |

changePattern

changePattern (patternCommand)

Sets , adds and/or removes pattern .

changePattern Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | patternCommand | Object | object with attributes "set , remove , add" and a pattern list | |

clear

clear ()

Clears the pattern tree

deletePattern

deletePattern (patternList)

Delete a pattern from the tree

deletePattern Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | patternList | Array, string | string or array of strings containing patterns to delete | |

getBestMatch

getBestMatch (searchTopic, isBetter) => {any}

Gets the best value of all matching pattern according the compare function . If no compare function is provided , the values of the patterns are compared with the ">" operator

getBestMatch Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | searchTopic | string | topic to search for | | | isBetter | function(newValue, currentValue | ( a , b ) function deciding , if "a" is better than "b" | |

getBestMatch returns

| Type | Description | | ---- | ----------- | | any | value associated with the best found topic or undefined , if nothing matches |

getFirstMatch

getFirstMatch (searchTopic) => {any, undefined}

Gets the value of the first matching pattern .

getFirstMatch Parameters

| Name | Type | Description | | ---------- | ------------ | ----------------- | | searchTopic | string | topic to search for | |

getFirstMatch returns

| Type | Description | | ---- | ----------- | | any, undefined | value associated with the found topic or undefined , if nothing matches |

toJSON

toJSON ()

hide the _tree from the JSON formatting