Add delete! for redis and relational

src/NonRelational/Redis.jl

@@ -60,14 +60,19 @@ function update!(mapper::DBMapper, ::Type{Redis.RedisConnection}, elem::T; field
     result = Redis.hmset(conn, id, data)
     release_connection(mapper.pool, conn)    
 end
-function exists(mapper::DBMapper, dbtype::Type{Redis.RedisConnection}, T::Type{<:Model}; kwargs...)
-    
+
+function extract_id_from_kwargs(mapper::DBMapper, T::Type{<:Model}; kwargs...)
     id_f = idfield(mapper, T)
     params = Dict(kwargs...)
     id = nothing
     if haskey(params, id_f)
         id = redis_id(T, pop!(params, id_f))        
     end    
+    return (id, params)
+end
+
+function exists(mapper::DBMapper, dbtype::Type{Redis.RedisConnection}, T::Type{<:Model}; kwargs...)
+    (id, params) = extract_id_from_kwargs(mapper, T; kwargs...)
     # Query with id
     if id !== nothing 
         # Only id
@@ -104,4 +109,39 @@ function exists(mapper::DBMapper, dbtype::Type{Redis.RedisConnection}, T::Type{<
         release_connection(mapper.pool, conn) 
     end
     return false
+end
+
+function Base.delete!(mapper::DBMapper, ::Type{Redis.RedisConnection}, T::Type{<:Model}; kwargs...) 
+    (id, params) = extract_id_from_kwargs(mapper, T; kwargs...)
+    if id !== nothing
+        if length(params) == 0
+            conn = get_connection(mapper.pool)                
+            result = Redis.del(conn, id)
+            release_connection(mapper.pool, conn) 
+        else
+            conn = get_connection(mapper.pool)    
+            params_key = collect(keys(params))
+            elem_values = Redis.hmget(conn, id, params_key...)
+            release_connection(mapper.pool, conn) 
+            elem = unmarshal(mapper, T, Dict(zip(params_key, elem_values)); partial=true)
+            if all([params[k] == elem[k] for k in params_key])
+                Redis.del(conn, id)
+            end
+        end
+    else
+        conn = get_connection(mapper.pool)        
+        cursor = -1
+        params_key = collect(keys(params))
+        while cursor != 0
+            (cursor, results) = Redis.scan(conn, cursor == -1 ? 0 : cursor, "match", redis_wildcard(T))
+            for elem_key in results
+                elem_values = Redis.hmget(conn, elem_key, params_key...)
+                elem = unmarshal(mapper, T, Dict(zip(params_key, elem_values)); partial=true)
+                if all([params[k] == elem[k] for k in params_key])                                    
+                    Redis.del(conn, elem_key)
+                end
+            end 
+            release_connection(mapper.pool, conn) 
+        end
+    end
 end

src/Relational/Relational.jl

@@ -247,3 +247,20 @@ function exists(mapper::DBMapper, dbtype::Type{Relational}, T::Type{<:Model}; kw
     result = result |> totuple
     return result[1][:count]
 end
+
+function Base.delete!(mapper::DBMapper, ::Type{Relational}, T::Type{<:Model}; kwargs...) 
+    dbtype = mapper.pool.dbtype
+    table = mapper.tables[T]
+    cnames = join(column_names(mapper, T), ", ")
+    conditions = join(["$field=?" for (field, value) in kwargs], " AND ")
+    values = [v[2] for v in kwargs]
+    sql = clean_sql("""
+    DELETE FROM $(table.name)
+    WHERE $(conditions)
+    """)
+    @info sql
+    conn = get_connection(mapper.pool)
+    stmt = DBInterface.prepare(conn, sql)
+    DBInterface.execute(stmt, values)
+    release_connection(mapper.pool, conn)    
+end

src/StructDatabaseMapping.jl

@@ -1,8 +1,10 @@
 module StructDatabaseMapping
+export select_one, update!, delete!, drop_table!, clean_table!,
+       update!, exists
+
 export DBMapper, register!, create_table, DBId, 
-       Nullable, analyze_relations, ForeignKey, select_one,
-       clean_table!, drop_table!, Model, getid, Foreign,
-       update!, exists, Cascade, SetNull, configure_relation,
+       Nullable, analyze_relations, ForeignKey,  Model, getid, Foreign,
+       Cascade, SetNull, configure_relation,
        Restrict
 
 using Dates
@@ -440,6 +442,18 @@ function exists(mapper::DBMapper, dbtype::DataType, T::Type{<:Model}; kwargs...)
     exists(mapper, database_kind(dbtype), T; kwargs...)
 end
 
+"""
+    function delete_one!(mapper::DBMapper, T::Type{<:Model}; kwargs...) 
+
+Select one element of type 
+"""
+function Base.delete!(mapper::DBMapper, T::Type{<:Model}; kwargs...) 
+    check_valid_type(mapper, T)
+    return delete!(mapper, mapper.pool.dbtype, T; kwargs...)
+end
+function Base.delete!(mapper::DBMapper, dbtype::DataType, T::Type{<:Model}; kwargs...) 
+    return delete!(mapper, database_kind(dbtype), T; kwargs...)
+end
 
 
 """

test/includes/basic_test.jl

@@ -19,6 +19,31 @@ function Book(;id::Union{String, Nothing}=nothing,
                author::Foreign{Author}=Author(),
                data::Dict{String, Integer}=Dict())
     return Book(id, author, data)
+end
+
+function _test_on_delete()
+    mapper = DBMapper(creator)
+    register!(mapper, Author)
+    register!(mapper, Book)
+    configure_relation(mapper, Book, :author, on_delete=Cascade())
+
+    author = Author(name="Author 1", age=50)
+    insert!(mapper, Author(name="Author 1", age=50))
+    insert!(mapper, Author(name="Author 2", age=50))
+    insert!(mapper, Author(name="Author 3", age=50))
+    insert!(mapper, Author(name="Author 4", age=50))
+
+    author1 = select_one(mapper, Author, name="Author 1")
+    author3 = select_one(mapper, Author, name="Author 3")
+
+    insert!(mapper, Book(author=author1, data=Dict("key"=>"Some 1")))
+    insert!(mapper, Book(author=author1, data=Dict("key"=>"Some 2")))
+    insert!(mapper, Book(author=author1, data=Dict("key"=>"Some 3")))
+
+    insert!(mapper, Book(author=author3, data=Dict("key"=>"Some 3")))
+
+
+
 end
 function _test_basic_functionalities(creator)
     mapper = DBMapper(creator)
@@ -82,10 +107,19 @@ function _test_basic_functionalities(creator)
     a = select_one(mapper, Book, id="bbb")
     @test isnothing(a)
     a = select_one(mapper, Book, id="super_string_id")
-    
+
     @test a.id.x == "super_string_id"
     @test get(a.author, mapper).name == "some_other_name"
     @test a.data["some_data"] == 5
+
+    author = select_one(mapper, Author, id=id)
+    @test author.name == "some_other_name"
+    @test author.age == 5
+    delete!(mapper, Author, name="some_other_name")
+    author = select_one(mapper, Author, id=id)
+    @test isnothing(author)
+
+