Holochain CRUD Library (CEPS pattern)

A CRUD library for Holochain zomes that implement the CEPS pattern (Chained, Entry, Permalink, State-based)

Holochain Version Map

For information on which versions of this package work for each Holochain release, see docs/HolochainVersionMap.md

Overview

Install

Example of adding to Cargo.toml toml [dependencies] hc_crud_ceps = "0.3.0"

Example of importing into your Rust file rust use hc_crud::{ now, get_origin_address, fetch_element, fetch_element_latest, create_entity, get_entity, update_entity, delete_entity, get_entities, Entity, Collection, EntryModel, EntityType, };

Basic Usage

CRUD Operations

These imports and structs are assumed for all examples ```rust use hdk::prelude::*; use hccrud::{ now, createentity, getentity, updateentity, deleteentity, getentities, Entity, Collection, EntryModel, EntityType, };

[hdk_entry(id = "post", visibility="public")]

[derive(Clone)]

pub struct PostEntry { pub title: String, pub message: String, pub publishedat: Option, pub lastupdated: Option, }

impl EntryModel for PostEntry { fn get_type(&self) -> EntityType { EntityType::new( "post", "entry" ) } } ```

Create an entry

Example ```rust let input = PostEntry { title: String::from("Greeting"), message: String::from("Hello world!"), publishedat: Some(1633108520744), lastupdated: None, };

let postentity = createentity( &input )?; ```

[Read] Get an entry

Example rust let post_entity = get_entity( &entity.id )?;

Update an entry

Example rust let post_entity = update_entity( &entity.address, |mut previous: PostEntry, _| { previous.message = String::from("Hello, world!"); previous.last_updated = Some( now()? ); Ok(previous) })?;

Delete an entry

Example rust delete_entity::<PostEntry>( &entity.id )?;

Example of CRUD for relationships

Create a 1-to-many relationship for post entries to have comment entries.

The following examples use this additional struct ```rust

[hdk_entry(id = "comment", visibility="public")]

[derive(Clone)]

pub struct CommentEntry { pub message: String, pub publishedat: Option, pub lastupdated: Option, }

impl EntryModel for CommentEntry { fn get_type(&self) -> EntityType { EntityType::new( "comment", "entry" ) } } ```

Create a CommentEntry and link it to the PostEntry ```rust const TAG_COMMENT: &'static str = "comment";

let input = CommentEntry { message: String::from("Where is the sun?"), publishedat: Some( now()? ), lastupdated: None, };

let commententity = createentity( &input )?;

commententity.linkfrom( &postentity.id, TAGCOMMENT.into() )?; ```

Get a Collection for a specific base and tag rust let collection = get_entities::<PostEntry, CommentEntry>( &post_entity.id, TAG_COMMENT.into() )?;

API Reference

See docs.rs/hccrudceps

Contributing

See CONTRIBUTING.md