Adding support for storing snapshots with any time resolution in CSV files and File System Repository. (#268)

# Describe Request

This is to allow using different date time formats to store snapshots at
various resolutions and no longer just days.

Added support for configuring the CSV file, and the File System
Repository.

- `asset.Snapshot.Date` no longer has a date format declared as a struct
tag.
- `helper.NewCsv` takes options to configure headers, logger, and the
default date time format.
- `asset.NewFileSystemRepository` also takes CSV options to configure
the CSV files.

Example:

```golang
csv, err := helper.NewCsv[Row](
	helper.WithCsvDefaultDateTimeFormat[Row]("2006-01-02 15:04:05"),
)
```

Related #266 

# Change Type

New feature.


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

Based on the comprehensive summary, here are the release notes:

- **New Features**
  - Enhanced CSV handling with more flexible configuration options
  - Introduced functional options for CSV processing
  - Added new configuration methods for CSV operations

- **Improvements**
  - Simplified CSV reading functions
  - Removed hardcoded boolean parameters in CSV file reading
  - Updated default date format handling

- **Refactoring**
  - Restructured CSV-related functions to use variadic options
  - Modified function signatures across multiple packages
  - Streamlined CSV data processing methods

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: cinar

asset/README.md

@@ -34,7 +34,7 @@ The information provided on this project is strictly for informational purposes
 - [func SnapshotsAsOpenings\(snapshots \<\-chan \*Snapshot\) \<\-chan float64](<#SnapshotsAsOpenings>)
 - [func SnapshotsAsVolumes\(snapshots \<\-chan \*Snapshot\) \<\-chan float64](<#SnapshotsAsVolumes>)
 - [type FileSystemRepository](<#FileSystemRepository>)
-  - [func NewFileSystemRepository\(base string\) \*FileSystemRepository](<#NewFileSystemRepository>)
+  - [func NewFileSystemRepository\(base string, csvOptions ...helper.CsvOption\[Snapshot\]\) \*FileSystemRepository](<#NewFileSystemRepository>)
   - [func \(r \*FileSystemRepository\) Append\(name string, snapshots \<\-chan \*Snapshot\) error](<#FileSystemRepository.Append>)
   - [func \(r \*FileSystemRepository\) Assets\(\) \(\[\]string, error\)](<#FileSystemRepository.Assets>)
   - [func \(r \*FileSystemRepository\) Get\(name string\) \(\<\-chan \*Snapshot, error\)](<#FileSystemRepository.Get>)
@@ -183,7 +183,7 @@ func SnapshotsAsVolumes(snapshots <-chan *Snapshot) <-chan float64
 SnapshotsAsVolumes extracts the volume field from each snapshot in the provided channel and returns a new channel containing only those volume values.The original snapshots channel can no longer be directly used afterward.
 
 <a name="FileSystemRepository"></a>
-## type [FileSystemRepository](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L20-L23>)
+## type [FileSystemRepository](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L20-L26>)
 
 FileSystemRepository stores and retrieves asset snapshots using the local file system.
 
@@ -194,16 +194,16 @@ type FileSystemRepository struct {
 ```
 
 <a name="NewFileSystemRepository"></a>
-### func [NewFileSystemRepository](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L27>)
+### func [NewFileSystemRepository](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L30>)
 
 ```go
-func NewFileSystemRepository(base string) *FileSystemRepository
+func NewFileSystemRepository(base string, csvOptions ...helper.CsvOption[Snapshot]) *FileSystemRepository
 ```
 
-NewFileSystemRepository initializes a file system repository with the given base directory.
+NewFileSystemRepository initializes a file system repository with the given base directory and the CSV options.
 
 <a name="FileSystemRepository.Append"></a>
-### func \(\*FileSystemRepository\) [Append](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L92>)
+### func \(\*FileSystemRepository\) [Append](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L96>)
 
 ```go
 func (r *FileSystemRepository) Append(name string, snapshots <-chan *Snapshot) error
@@ -212,7 +212,7 @@ func (r *FileSystemRepository) Append(name string, snapshots <-chan *Snapshot) e
 Append adds the given snapshows to the asset with the given name.
 
 <a name="FileSystemRepository.Assets"></a>
-### func \(\*FileSystemRepository\) [Assets](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L34>)
+### func \(\*FileSystemRepository\) [Assets](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L38>)
 
 ```go
 func (r *FileSystemRepository) Assets() ([]string, error)
@@ -221,7 +221,7 @@ func (r *FileSystemRepository) Assets() ([]string, error)
 Assets returns the names of all assets in the repository.
 
 <a name="FileSystemRepository.Get"></a>
-### func \(\*FileSystemRepository\) [Get](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L56>)
+### func \(\*FileSystemRepository\) [Get](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L60>)
 
 ```go
 func (r *FileSystemRepository) Get(name string) (<-chan *Snapshot, error)
@@ -230,7 +230,7 @@ func (r *FileSystemRepository) Get(name string) (<-chan *Snapshot, error)
 Get attempts to return a channel of snapshots for the asset with the given name.
 
 <a name="FileSystemRepository.GetSince"></a>
-### func \(\*FileSystemRepository\) [GetSince](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L61>)
+### func \(\*FileSystemRepository\) [GetSince](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L65>)
 
 ```go
 func (r *FileSystemRepository) GetSince(name string, date time.Time) (<-chan *Snapshot, error)
@@ -239,7 +239,7 @@ func (r *FileSystemRepository) GetSince(name string, date time.Time) (<-chan *Sn
 GetSince attempts to return a channel of snapshots for the asset with the given name since the given date.
 
 <a name="FileSystemRepository.LastDate"></a>
-### func \(\*FileSystemRepository\) [LastDate](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L75>)
+### func \(\*FileSystemRepository\) [LastDate](<https://github.com/cinar/indicator/blob/master/asset/file_system_repository.go#L79>)
 
 ```go
 func (r *FileSystemRepository) LastDate(name string) (time.Time, error)
@@ -476,7 +476,7 @@ Snapshot captures a single observation of an asset's price at a specific moment.
 ```go
 type Snapshot struct {
     // Date represents the specific timestamp.
-    Date time.Time `format:"2006-01-02"`
+    Date time.Time
 
     // Open represents the opening price for the
     // snapshot period.

asset/file_system_repository.go

@@ -20,13 +20,17 @@ import (
 type FileSystemRepository struct {
 	// base is the root directory where asset snapshots are stored.
 	base string
+
+	// csvOptions are the CSV options used for reading and writing snapshots.
+	csvOptions []helper.CsvOption[Snapshot]
 }
 
 // NewFileSystemRepository initializes a file system repository with
-// the given base directory.
-func NewFileSystemRepository(base string) *FileSystemRepository {
+// the given base directory and the CSV options.
+func NewFileSystemRepository(base string, csvOptions ...helper.CsvOption[Snapshot]) *FileSystemRepository {
 	return &FileSystemRepository{
-		base: base,
+		base:       base,
+		csvOptions: csvOptions,
 	}
 }
 
@@ -54,7 +58,7 @@ func (r *FileSystemRepository) Assets() ([]string, error) {
 
 // Get attempts to return a channel of snapshots for the asset with the given name.
 func (r *FileSystemRepository) Get(name string) (<-chan *Snapshot, error) {
-	return helper.ReadFromCsvFile[Snapshot](r.getCsvFileName(name), true)
+	return helper.ReadFromCsvFile[Snapshot](r.getCsvFileName(name), r.csvOptions...)
 }
 
 // GetSince attempts to return a channel of snapshots for the asset with the given name since the given date.
@@ -90,7 +94,7 @@ func (r *FileSystemRepository) LastDate(name string) (time.Time, error) {
 
 // Append adds the given snapshows to the asset with the given name.
 func (r *FileSystemRepository) Append(name string, snapshots <-chan *Snapshot) error {
-	return helper.AppendOrWriteToCsvFile(r.getCsvFileName(name), true, snapshots)
+	return helper.AppendOrWriteToCsvFile(r.getCsvFileName(name), snapshots, r.csvOptions...)
 }
 
 // getCsvFileName gets the CSV file name for the given asset name.

asset/file_system_repository_test.go

@@ -69,7 +69,7 @@ func TestFileSystemRepositoryGetSince(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	expected, err := helper.ReadFromCsvFile[asset.Snapshot]("testdata/since.csv", true)
+	expected, err := helper.ReadFromCsvFile[asset.Snapshot]("testdata/since.csv")
 	if err != nil {
 		t.Fatal(err)
 	}

asset/snapshot.go

@@ -14,7 +14,7 @@ import (
 // at a specific moment.
 type Snapshot struct {
 	// Date represents the specific timestamp.
-	Date time.Time `format:"2006-01-02"`
+	Date time.Time
 
 	// Open represents the opening price for the
 	// snapshot period.

asset/snapshot_test.go

@@ -12,7 +12,7 @@ import (
 )
 
 func TestSnapshotsAs(t *testing.T) {
-	snapshots, err := helper.ReadFromCsvFile[asset.Snapshot]("testdata/repository/brk-b.csv", true)
+	snapshots, err := helper.ReadFromCsvFile[asset.Snapshot]("testdata/repository/brk-b.csv")
 	if err != nil {
 		t.Fatal(err)
 	}

helper/README.md

@@ -27,7 +27,7 @@ The information provided on this project is strictly for informational purposes
 - [Constants](<#constants>)
 - [func Abs\[T Number\]\(c \<\-chan T\) \<\-chan T](<#Abs>)
 - [func Add\[T Number\]\(ac, bc \<\-chan T\) \<\-chan T](<#Add>)
-- [func AppendOrWriteToCsvFile\[T any\]\(fileName string, hasHeader bool, rows \<\-chan \*T\) error](<#AppendOrWriteToCsvFile>)
+- [func AppendOrWriteToCsvFile\[T any\]\(fileName string, rows \<\-chan \*T, options ...CsvOption\[T\]\) error](<#AppendOrWriteToCsvFile>)
 - [func Apply\[T Number\]\(c \<\-chan T, f func\(T\) T\) \<\-chan T](<#Apply>)
 - [func Buffered\[T any\]\(c \<\-chan T, size int\) \<\-chan T](<#Buffered>)
 - [func ChanToJSON\[T any\]\(c \<\-chan T, w io.Writer\) error](<#ChanToJSON>)
@@ -69,7 +69,7 @@ The information provided on this project is strictly for informational purposes
 - [func Operate3\[A any, B any, C any, R any\]\(ac \<\-chan A, bc \<\-chan B, cc \<\-chan C, o func\(A, B, C\) R\) \<\-chan R](<#Operate3>)
 - [func Pipe\[T any\]\(f \<\-chan T, t chan\<\- T\)](<#Pipe>)
 - [func Pow\[T Number\]\(c \<\-chan T, y T\) \<\-chan T](<#Pow>)
-- [func ReadFromCsvFile\[T any\]\(fileName string, hasHeader bool\) \(\<\-chan \*T, error\)](<#ReadFromCsvFile>)
+- [func ReadFromCsvFile\[T any\]\(fileName string, options ...CsvOption\[T\]\) \(\<\-chan \*T, error\)](<#ReadFromCsvFile>)
 - [func Remove\(t \*testing.T, name string\)](<#Remove>)
 - [func RemoveAll\(t \*testing.T, path string\)](<#RemoveAll>)
 - [func RoundDigit\[T Number\]\(n T, d int\) T](<#RoundDigit>)
@@ -93,11 +93,15 @@ The information provided on this project is strictly for informational purposes
   - [func \(b \*Bst\[T\]\) Remove\(value T\) bool](<#Bst[T].Remove>)
 - [type BstNode](<#BstNode>)
 - [type Csv](<#Csv>)
-  - [func NewCsv\[T any\]\(hasHeader bool\) \(\*Csv\[T\], error\)](<#NewCsv>)
+  - [func NewCsv\[T any\]\(options ...CsvOption\[T\]\) \(\*Csv\[T\], error\)](<#NewCsv>)
   - [func \(c \*Csv\[T\]\) AppendToFile\(fileName string, rows \<\-chan \*T\) error](<#Csv[T].AppendToFile>)
   - [func \(c \*Csv\[T\]\) ReadFromFile\(fileName string\) \(\<\-chan \*T, error\)](<#Csv[T].ReadFromFile>)
   - [func \(c \*Csv\[T\]\) ReadFromReader\(reader io.Reader\) \<\-chan \*T](<#Csv[T].ReadFromReader>)
   - [func \(c \*Csv\[T\]\) WriteToFile\(fileName string, rows \<\-chan \*T\) error](<#Csv[T].WriteToFile>)
+- [type CsvOption](<#CsvOption>)
+  - [func WithCsvDefaultDateTimeFormat\[T any\]\(format string\) CsvOption\[T\]](<#WithCsvDefaultDateTimeFormat>)
+  - [func WithCsvLogger\[T any\]\(logger \*slog.Logger\) CsvOption\[T\]](<#WithCsvLogger>)
+  - [func WithoutCsvHeader\[T any\]\(\) CsvOption\[T\]](<#WithoutCsvHeader>)
 - [type Float](<#Float>)
 - [type Integer](<#Integer>)
 - [type Number](<#Number>)
@@ -132,7 +136,7 @@ const (
     CsvFormatTag = "format"
 
     // DefaultDateTimeFormat denotes the default format of a date and time column.
-    DefaultDateTimeFormat = "2006-01-02 15:04:05"
+    DefaultDateTimeFormat = "2006-01-02"
 )
 ```
 
@@ -182,10 +186,10 @@ fmt.Println(actual) // [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
 ```
 
 <a name="AppendOrWriteToCsvFile"></a>
-## func [AppendOrWriteToCsvFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L291>)
+## func [AppendOrWriteToCsvFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L323>)
 
 ```go
-func AppendOrWriteToCsvFile[T any](fileName string, hasHeader bool, rows <-chan *T) error
+func AppendOrWriteToCsvFile[T any](fileName string, rows <-chan *T, options ...CsvOption[T]) error
 ```
 
 AppendOrWriteToCsvFile writes the provided rows of data to the specified file, appending to the existing file if it exists or creating a new one if it doesn't. In append mode, the function assumes that the existing file's column order matches the field order of the given row struct to ensure consistent data structure.
@@ -805,10 +809,10 @@ fmt.Println(helper.ChanToSlice(squared)) // [4, 9, 25, 100]
 ```
 
 <a name="ReadFromCsvFile"></a>
-## func [ReadFromCsvFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L278>)
+## func [ReadFromCsvFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L310>)
 
 ```go
-func ReadFromCsvFile[T any](fileName string, hasHeader bool) (<-chan *T, error)
+func ReadFromCsvFile[T any](fileName string, options ...CsvOption[T]) (<-chan *T, error)
 ```
 
 ReadFromCsvFile creates a CSV instance, parses CSV data from the provided filename, maps the data to corresponding struct fields, and delivers it through the channel.
@@ -1095,7 +1099,7 @@ type BstNode[T Number] struct {
 ```
 
 <a name="Csv"></a>
-## type [Csv](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L40-L50>)
+## type [Csv](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L40-L53>)
 
 Csv represents the configuration for CSV reader and writer.
 
@@ -1109,16 +1113,16 @@ type Csv[T any] struct {
 ```
 
 <a name="NewCsv"></a>
-### func [NewCsv](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L54>)
+### func [NewCsv](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L80>)
 
 ```go
-func NewCsv[T any](hasHeader bool) (*Csv[T], error)
+func NewCsv[T any](options ...CsvOption[T]) (*Csv[T], error)
 ```
 
-NewCsv function initializes a new CSV instance. The parameter hasHeader indicates whether the CSV contains a header row.
+NewCsv creates a new CSV instance with the provided options.
 
 <a name="Csv[T].AppendToFile"></a>
-### func \(\*Csv\[T\]\) [AppendToFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L174>)
+### func \(\*Csv\[T\]\) [AppendToFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L206>)
 
 ```go
 func (c *Csv[T]) AppendToFile(fileName string, rows <-chan *T) error
@@ -1127,7 +1131,7 @@ func (c *Csv[T]) AppendToFile(fileName string, rows <-chan *T) error
 AppendToFile appends the provided rows of data to the end of the specified file, creating the file if it doesn't exist. In append mode, the function assumes that the existing file's column order matches the field order of the given row struct to ensure consistent data structure.
 
 <a name="Csv[T].ReadFromFile"></a>
-### func \(\*Csv\[T\]\) [ReadFromFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L150>)
+### func \(\*Csv\[T\]\) [ReadFromFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L182>)
 
 ```go
 func (c *Csv[T]) ReadFromFile(fileName string) (<-chan *T, error)
@@ -1136,7 +1140,7 @@ func (c *Csv[T]) ReadFromFile(fileName string) (<-chan *T, error)
 ReadFromFile parses the CSV data from the provided file name, maps the data to corresponding struct fields, and delivers the resulting rows through the channel.
 
 <a name="Csv[T].ReadFromReader"></a>
-### func \(\*Csv\[T\]\) [ReadFromReader](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L95>)
+### func \(\*Csv\[T\]\) [ReadFromReader](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L127>)
 
 ```go
 func (c *Csv[T]) ReadFromReader(reader io.Reader) <-chan *T
@@ -1145,14 +1149,50 @@ func (c *Csv[T]) ReadFromReader(reader io.Reader) <-chan *T
 ReadFromReader parses the CSV data from the provided reader, maps the data to corresponding struct fields, and delivers the resulting it through the channel.
 
 <a name="Csv[T].WriteToFile"></a>
-### func \(\*Csv\[T\]\) [WriteToFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L190>)
+### func \(\*Csv\[T\]\) [WriteToFile](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L222>)
 
 ```go
 func (c *Csv[T]) WriteToFile(fileName string, rows <-chan *T) error
 ```
 
 WriteToFile creates a new file with the given name and writes the provided rows of data to it, overwriting any existing content.
 
+<a name="CsvOption"></a>
+## type [CsvOption](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L56>)
+
+CsvOption represents a functional option for configuring the CSV instance.
+
+```go
+type CsvOption[T any] func(*Csv[T])
+```
+
+<a name="WithCsvDefaultDateTimeFormat"></a>
+### func [WithCsvDefaultDateTimeFormat](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L73>)
+
+```go
+func WithCsvDefaultDateTimeFormat[T any](format string) CsvOption[T]
+```
+
+WithCsvDefaultDateTimeFormat sets the default date and time format for the CSV instance.
+
+<a name="WithCsvLogger"></a>
+### func [WithCsvLogger](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L66>)
+
+```go
+func WithCsvLogger[T any](logger *slog.Logger) CsvOption[T]
+```
+
+WithCsvLogger sets the logger for the CSV instance.
+
+<a name="WithoutCsvHeader"></a>
+### func [WithoutCsvHeader](<https://github.com/cinar/indicator/blob/master/helper/csv.go#L59>)
+
+```go
+func WithoutCsvHeader[T any]() CsvOption[T]
+```
+
+WithoutCsvHeader disables the header row in the CSV.
+
 <a name="Float"></a>
 ## type [Float](<https://github.com/cinar/indicator/blob/master/helper/helper.go#L27-L29>)