icjs-mpt

### Table of Contents - [Trie][1] - [Parameters][2] - [Properties][3] - [get][4] - [Parameters][5] - [put][6] - [Parameters][7] - [del][8] - [Parameters][9] - [getRaw][10] - [Parameters][11] - [putRaw][12] - [Parameters][13] - [delRaw][14] - [Parameters][15] - [findPath][16] - [Parameters][17] - [\_updateNode][18] - [Parameters][19] - [\_saveStack][20] - [Parameters][21] - [createReadStream][22] - [batch][23] - [Parameters][24] - [Examples][25] - [checkRoot][26] - [Parameters][27] - [PrioritizedTaskExecutor][28] - [Parameters][29] - [Properties][30] - [execute][31] - [Parameters][32] - [checkpoint][33] - [commit][34] - [Parameters][35] - [revert][36] - [Parameters][37] - [Trie.prove][38] - [Parameters][39] - [Trie.verifyProof][40] - [Parameters][41] - [addHexPrefix][42] - [Parameters][43] - [isTerminator][44] - [Parameters][45] - [stringToNibbles][46] - [Parameters][47] - [nibblesToBuffer][48] - [Parameters][49] - [getNodeType][50] - [Parameters][51] - [matchingNibbleLength][52] - [Parameters][53] - [doKeysMatch][54] - [Parameters][55] - [callTogether][56] - [asyncFirstSeries][57] - [Parameters][58] - [SecureTrie][59] ## Trie Use `require('merkel-patricia-tree')` for the base interface. In IrChain applications stick with the Secure Trie Overlay `require('merkel-patricia-tree/secure')`. The API for the raw and the secure interface are about the same ### Parameters - `db` **[Object][60]?** An instance of [levelup][61] or a compatible API. If the db is `null` or left undefined, then the trie will be stored in memory via [memdown][62] - `root` **([Buffer][63] \| [String][64])?** `A hex`String`or`Buffer\` for the root of a previously stored trie ### Properties - `root` **[Buffer][63]** The current root of the `trie` - `isCheckpoint` **[Boolean][65]** determines if you are saving to a checkpoint or directly to the db - `EMPTY_TRIE_ROOT` **[Buffer][63]** the Root for an empty trie ## get Gets a value given a `key` ### Parameters - `key` **([Buffer][63] \| [String][64])** the key to search for - `cb` **[Function][66]** A callback `Function` which is given the arguments `err` - for errors that may have occured and `value` - the found value in a `Buffer` or if no value was found `null` ## put Stores a given `value` at the given `key` ### Parameters - `key` **([Buffer][63] \| [String][64])** - `Value` **([Buffer][63] \| [String][64])** - `cb` **[Function][66]** A callback `Function` which is given the argument `err` - for errors that may have occured ## del deletes a value given a `key` ### Parameters - `key` **([Buffer][63] \| [String][64])** - `callback` **[Function][66]** the callback `Function` ## getRaw Retrieves a raw value in the underlying db ### Parameters - `key` **[Buffer][63]** - `callback` **[Function][66]** A callback `Function`, which is given the arguments `err` - for errors that may have occured and `value` - the found value in a `Buffer` or if no value was found `null`. ## putRaw Writes a value directly to the underlining db ### Parameters - `key` **([Buffer][63] \| [String][64])** The key as a `Buffer` or `String` - `value` **[Buffer][63]** The value to be stored - `callback` **[Function][66]** A callback `Function`, which is given the argument `err` - for errors that may have occured ## delRaw Removes a raw value in the underlying db ### Parameters - `key` **([Buffer][63] \| [String][64])** - `callback` **[Function][66]** A callback `Function`, which is given the argument `err` - for errors that may have occured ## findPath Trys to find a path to the node for the given key It returns a `stack` of nodes to the closet node ### Parameters - `null-null` **([String][64] \| [Buffer][63])** key - the search key - `null-null` **[Function][66]** cb - the callback function. Its is given the following arguments- err - any errors encontered - node - the last node found - keyRemainder - the remaining key nibbles not accounted for - stack - an array of nodes that forms the path to node we are searching for ## \_updateNode Updates a node ### Parameters - `key` **[Buffer][63]** - `value` **([Buffer][63] \| [String][64])** - `keyRemainder` **[Array][67]** - `stack` **[Array][67]** \- - `cb` **[Function][66]** the callback ## \_saveStack saves a stack ### Parameters - `key` **[Array][67]** the key. Should follow the stack - `stack` **[Array][67]** a stack of nodes to the value given by the key - `opStack` **[Array][67]** a stack of levelup operations to commit at the end of this funciton - `cb` **[Function][66]** ## createReadStream The `data` event is given an `Object` hat has two properties; the `key` and the `value`. Both should be Buffers. Returns **[stream.Readable][68]** Returns a [stream][69] of the contents of the `trie` ## batch The given hash of operations (key additions or deletions) are executed on the DB ### Parameters - `ops` **[Array][67]** - `cb` **[Function][66]** ### Examples ```javascript var ops = [ { type: 'del', key: 'father' } , { type: 'put', key: 'name', value: 'Yuri Irsenovich Kim' } , { type: 'put', key: 'dob', value: '16 February 1941' } , { type: 'put', key: 'spouse', value: 'Kim Young-sook' } , { type: 'put', key: 'occupation', value: 'Clown' } ] trie.batch(ops) ``` ## checkRoot Checks if a given root exists ### Parameters - `root` **[Buffer][63]** - `cb` **[Function][66]** ## PrioritizedTaskExecutor Executes tasks up to maxPoolSize at a time, other items are put in a priority queue. ### Parameters - `maxPoolSize` **[Number][70]** The maximum size of the pool ### Properties - `maxPoolSize` **[Number][70]** The maximum size of the pool - `currentPoolSize` **[Number][70]** The current size of the pool - `queue` **[Array][67]** The task queue ### execute Executes the task. #### Parameters - `priority` **[Number][70]** The priority of the task - `task` **[Function][66]** The function that accepts the callback, which must be called upon the task completion. ## checkpoint Creates a checkpoint that can later be reverted to or committed. After this is called, no changes to the trie will be permanently saved until `commit` is called ## commit commits a checkpoint to disk ### Parameters - `cb` **[Function][66]** the callback ## revert Reverts the trie to the state it was at when `checkpoint` was first called. ### Parameters - `cb` **[Function][66]** the callback ## Trie.prove Returns a merkle proof for a given key ### Parameters - `trie` **[Trie][71]** - `key` **[String][64]** - `cb` **[Function][66]** A callback `Function` (arguments {Error} `err`, {Array.<TrieNode>} `proof`) ## Trie.verifyProof Verifies a merkle proof for a given key ### Parameters - `rootHash` **[Buffer][63]** - `key` **[String][64]** - `proof` **[Array][67]<TrieNode>** - `cb` **[Function][66]** A callback `Function` (arguments {Error} `err`, {String} `val`) ## addHexPrefix ### Parameters - `key` - `terminator` - `dataArr` **[Array][67]** Returns **[Buffer][63]** returns buffer of encoded data hexPrefix \* ## isTerminator Determines if a key has Arnold Schwarzenegger in it. ### Parameters - `key` **[Array][67]** an hexprefixed array of nibbles ## stringToNibbles Converts a string OR a buffer to a nibble array. ### Parameters - `key` **([Buffer][63] \| [String][64])** ## nibblesToBuffer Converts a nibble array into a buffer. ### Parameters - `arr` ## getNodeType Determines the node type. ### Parameters - `node` Returns **[String][64]** the node type- leaf - if the node is a leaf - branch - if the node is a branch - extention - if the node is an extention - unknown - if something else got borked ## matchingNibbleLength Returns the number of in order matching nibbles of two give nibble arrayes ### Parameters - `nib1` **[Array][67]** - `nib2` **[Array][67]** ## doKeysMatch Compare two 'nibble array' keys ### Parameters - `keyA` - `keyB` ## callTogether Take two or more functions and returns a function that will execute all of the given functions ## asyncFirstSeries Take a collection of async fns, call the cb on the first to return a truthy value. If all run without a truthy result, return undefined ### Parameters - `array` - `iterator` - `cb` ## SecureTrie **Extends Trie** You can create a secure Trie where the keys are automatically hashed using **SHA3** by using `require('icjs-mpt/secure')`. It has the same methods and constuctor as `Trie` [1]: #trie [2]: #parameters [3]: #properties [4]: #get [5]: #parameters-1 [6]: #put [7]: #parameters-2 [8]: #del [9]: #parameters-3 [10]: #getraw [11]: #parameters-4 [12]: #putraw [13]: #parameters-5 [14]: #delraw [15]: #parameters-6 [16]: #findpath [17]: #parameters-7 [18]: #_updatenode [19]: #parameters-8 [20]: #_savestack [21]: #parameters-9 [22]: #createreadstream [23]: #batch [24]: #parameters-10 [25]: #examples [26]: #checkroot [27]: #parameters-11 [28]: #prioritizedtaskexecutor [29]: #parameters-12 [30]: #properties-1 [31]: #execute [32]: #parameters-13 [33]: #checkpoint [34]: #commit [35]: #parameters-14 [36]: #revert [37]: #parameters-15 [38]: #trieprove [39]: #parameters-16 [40]: #trieverifyproof [41]: #parameters-17 [42]: #addhexprefix [43]: #parameters-18 [44]: #isterminator [45]: #parameters-19 [46]: #stringtonibbles [47]: #parameters-20 [48]: #nibblestobuffer [49]: #parameters-21 [50]: #getnodetype [51]: #parameters-22 [52]: #matchingnibblelength [53]: #parameters-23 [54]: #dokeysmatch [55]: #parameters-24 [56]: #calltogether [57]: #asyncfirstseries [58]: #parameters-25 [59]: #securetrie [60]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object [61]: https://github.com/rvagg/node-levelup/ [62]: https://github.com/rvagg/memdown [63]: https://nodejs.org/api/buffer.html [64]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String [65]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean [66]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function [67]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array [68]: https://nodejs.org/api/stream.html#stream_class_stream_readable [69]: https://nodejs.org/dist/latest-v5.x/docs/api/stream.html#stream_class_stream_readable [70]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number [71]: #trie