From a05d26418f7434d440c13ff51ccfd8bc3a24e62e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Vin=C3=ADcius=20Garcia?= Date: Wed, 28 Oct 2020 21:30:10 -0300 Subject: [PATCH] Improve comments for the QueryChunks func --- contracts.go | 7 +++++-- kiss_orm.go | 25 ++++++++++++++----------- 2 files changed, 19 insertions(+), 13 deletions(-) diff --git a/contracts.go b/contracts.go index 006ee77..35ccc23 100644 --- a/contracts.go +++ b/contracts.go @@ -31,8 +31,11 @@ type ChunkParser struct { ChunkSize int - // This attribute must be a func(chunk []) error, - // where the actual Record should be a struct + // This attribute must be a function with the following signature: + // + // `func(chunk []) error`. + // + // Where the actual Record type should be of a struct // representing the rows you are expecting to receive. ForEachChunk interface{} } diff --git a/kiss_orm.go b/kiss_orm.go index 15561cf..a3731f3 100644 --- a/kiss_orm.go +++ b/kiss_orm.go @@ -112,18 +112,21 @@ func (c Client) QueryOne( } // QueryChunks is meant to perform queries that returns -// many results and should only be used for that purpose. +// more results than would normally fit on memory, +// for others cases the Query and QueryOne functions are indicated. // -// It ChunkParser argument will inform the query and its params, -// and the information that will be used to iterate on the results, -// namely: -// (1) The Chunk, which must be a pointer to a slice of structs where -// the results of the query will be kept on each iteration. -// (2) The ChunkSize that describes how many rows should be loaded -// on the Chunk slice before running the iteration callback. -// (3) The ForEachChunk function, which is the iteration callback -// and will be called right after the Chunk is filled with rows -// and/or after the last row is read from the database. +// The ChunkParser argument has 4 attributes: +// (1) The Query; +// (2) The query args; +// (3) The chunk size; +// (4) A callback function called ForEachChunk, that will be called +// to process each chunk loaded from the database. +// +// Note that the signature of the ForEachChunk callback can be +// any function that receives a slice of structs or a slice of +// pointers to struct as its only argument and that reflection +// will be used to instantiate this argument and to fill it +// with the database rows. func (c Client) QueryChunks( ctx context.Context, parser ChunkParser,