private static string GetTypeHint(TypeDecl decl, ElementDecl element)
{
string GetParamNamespace(TypeDecl declaration, IDeclKey key) =>
!PyExtensions.IsPackageEquals(declaration, key) ? PyExtensions.GetAlias(key) + "." : "";
string GetFinalHint(string typeHint) =>
element.Vector == YesNo.Y ? $"List[{typeHint}]" : typeHint;
if (element.Value != null)
{
string hint = GetValue(element.Value);
return(GetFinalHint(hint));
}
else if (element.Data != null)
{
string paramNamespace = GetParamNamespace(decl, element.Data);
string hint = $"{paramNamespace}{element.Data.Name}";
return(GetFinalHint(hint));
}
else if (element.Key != null)
{
return(GetFinalHint("str"));
}
else if (element.Enum != null)
{
string paramNamespace = GetParamNamespace(decl, element.Enum);
string hint = $"{paramNamespace}{element.Enum.Name}";
return(GetFinalHint(hint));
}
else
{
throw new ArgumentException("Can't deduct type");
}
}
private static string GetTypeHint(TypeDecl decl, ParamDecl parameter)
{
if (parameter.Value != null)
{
string result = GetValue(parameter.Value);
return(parameter.Vector == YesNo.Y ? $"List[{result}]" : result);
}
else if (parameter.Data != null)
{
string paramNamespace = !PyExtensions.IsPackageEquals(decl, parameter.Data)
? PyExtensions.GetAlias(parameter.Data) + "."
: "";
string result = $"{paramNamespace}{parameter.Data.Name}";
return(parameter.Vector == YesNo.Y ? $"List[{result}]" : result);
}
else if (parameter.Key != null)
{
return(parameter.Vector == YesNo.Y ? "List[str]" : "str");
}
else if (parameter.Enum != null)
{
string paramNamespace = !PyExtensions.IsPackageEquals(decl, parameter.Enum)
? PyExtensions.GetAlias(parameter.Enum) + "."
: "";
string result = $"{paramNamespace}{parameter.Enum.Name}";
return(parameter.Vector == YesNo.Y ? $"List[{result}]" : result);
}
else
{
throw new ArgumentException("Can't deduct type");
}
}
/// <summary>
/// Generate python classes from declaration.
/// </summary>
public static string Build(TypeDecl decl, List <IDecl> declarations)
{
var writer = new CodeWriter();
string name = decl.Name;
// Determine if we are inside datacentric package
// based on module name. This affects the imports
// and namespace use.
bool insideDc = PyExtensions.GetPackage(decl) == "datacentric";
// If not generating for DataCentric package, use dc. namespace
// in front of datacentric types, otherwise use no prefix
string dcNamespacePrefix = insideDc ? "" : "dc.";
PythonImportsBuilder.WriteImports(decl, declarations, writer);
writer.AppendNewLineWithoutIndent();
writer.AppendNewLineWithoutIndent();
// Get base classes for current declaration
List <string> bases = new List <string>();
if (decl.Keys.Any())
{
bases.Add(dcNamespacePrefix + "Record");
}
else if (decl.Inherit != null)
{
// Full package name and short namespace of the parent class,
// or null if there is no parent
bool parentClassInDifferentModule = !PyExtensions.IsPackageEquals(decl, decl.Inherit);
string parentPackage = PyExtensions.GetPackage(decl.Inherit);
string parentClassNamespacePrefix =
parentClassInDifferentModule ? PyExtensions.GetAlias(parentPackage) + "." : "";
bases.Add(parentClassNamespacePrefix + decl.Inherit.Name);
}
else
{
bases.Add(dcNamespacePrefix + "Data");
}
if (decl.Kind == TypeKind.Abstract)
{
bases.Add("ABC");
}
// Python 3.8:
// if (decl.Kind == TypeKind.Final)
// writer.AppendLine("@final");
writer.AppendLine("@attr.s(slots=True, auto_attribs=True)");
writer.AppendLine($"class {name}({string.Join(", ", bases)}):");
writer.PushIndent();
writer.AppendLines(CommentHelper.PyComment(decl.Comment));
writer.AppendNewLineWithoutIndent();
if (!decl.Elements.Any())
{
writer.AppendLine("pass");
}
foreach (var element in decl.Elements)
{
// TODO: Should be replaced with callable with specific format instead of skipping
string skipRepresentation = element.Vector == YesNo.Y ? ", repr=False" : "";
writer.AppendLine($"{element.Name.Underscore()}: {GetTypeHint(decl, element)} = attr.ib(default=None, kw_only=True{skipRepresentation}{GetMetaData(element)})");
writer.AppendLines(CommentHelper.PyComment(element.Comment));
if (element != decl.Elements.Last())
{
writer.AppendNewLineWithoutIndent();
}
}
// Add to_key and create_key() methods
if (decl.Keys.Any())
{
var keyElements = decl.Elements.Where(e => decl.Keys.Contains(e.Name)).ToList();
writer.AppendNewLineWithoutIndent();
writer.AppendLine("def to_key(self) -> str:");
writer.PushIndent();
writer.AppendLine(CommentHelper.PyComment($"Get {decl.Name} key."));
writer.AppendLines($"return '{decl.Name}='{GetToKeyArgs(decl.Name, keyElements, true)}");
writer.PopIndent();
writer.AppendNewLineWithoutIndent();
var namedParams = keyElements.Select(e => $"{e.Name.Underscore()}: {GetTypeHint(decl, e)}").ToList();
var joinedNamedParams = string.Join(", ", namedParams);
string start = "def create_key(";
// Check if tokens should be separated by new line
if (4 + start.Length + joinedNamedParams.Length > 120)
{
var indent = new string(' ', start.Length);
joinedNamedParams = string.Join("," + Environment.NewLine + indent, namedParams);
}
writer.AppendLine("@classmethod");
writer.AppendLines($"def create_key(cls, *, {joinedNamedParams}) -> str:");
writer.PushIndent();
writer.AppendLine(CommentHelper.PyComment($"Create {decl.Name} key."));
writer.AppendLines($"return '{decl.Name}='{GetToKeyArgs(decl.Name, keyElements, false)}");
writer.PopIndent();
}
if (decl.Declare != null)
{
writer.AppendNewLineWithoutIndent();
WriteMethods(decl, writer);
}
// Class end
writer.PopIndent();
return(writer.ToString());
}
/// <summary>
/// Add import statements for given declaration.
/// </summary>
public static void WriteImports(TypeDecl decl, List <IDecl> declarations, CodeWriter writer)
{
// Always import attr module
writer.AppendLine("import attr");
// Instant is generated as Union[dt.datetime, dc.Instant] thus dt import is required
if (decl.Elements.Any(e => e.Value != null && (e.Value.Type == ValueParamType.Instant ||
e.Value.Type == ValueParamType.NullableInstant)))
{
writer.AppendLine("import datetime as dt");
}
// If type is abstract - ABC import is needed
if (decl.Kind == TypeKind.Abstract)
{
writer.AppendLine("from abc import ABC");
}
// Check if ObjectId is used
bool hasObjectId = decl.Elements.Any(e => e.Value != null &&
(e.Value.Type == ValueParamType.TemporalId ||
e.Value.Type == ValueParamType.NullableTemporalId));
if (hasObjectId)
{
writer.AppendLine("from bson import ObjectId");
}
// Check imports from typing
var typingImports = new List <string>();
// Python 3.8
// if (decl.Keys.Any() || decl.Kind == TypeKind.Final)
// typingImports.Add("final");
if (decl.Elements.Any(e => e.Vector == YesNo.Y))
{
typingImports.Add("List");
}
if (typingImports.Any())
{
var items = string.Join(", ", typingImports);
writer.AppendLine($"from typing import {items}");
}
bool insideDc = PyExtensions.GetPackage(decl) == "datacentric";
List <string> packagesToImport = new List <string>();
List <string> individualImports = new List <string>();
// Import parent class package as its namespace, or if inside the same package,
// import individual class instead
if (decl.Inherit != null)
{
if (PyExtensions.IsPackageEquals(decl, decl.Inherit))
{
IDecl parentDecl = declarations.FindByKey(decl.Inherit);
individualImports.Add($"from {parentDecl.Category} import {decl.Inherit.Name}");
}
else
{
packagesToImport.Add(PyExtensions.GetPackage(decl.Inherit));
}
}
// Import datacentric package as dc, or if inside datacentric,
// import individual classes instead
else if (decl.IsRecord)
{
if (insideDc)
{
individualImports.Add("from datacentric.storage.record import Record");
}
else
{
packagesToImport.Add("datacentric");
}
}
// First child class of Data
else
{
if (insideDc)
{
individualImports.Add("from datacentric.storage.data import Data");
}
else
{
packagesToImport.Add("datacentric");
}
}
foreach (var data in decl.Elements.Where(d => d.Data != null).Select(d => d.Data))
{
if (PyExtensions.IsPackageEquals(decl, data))
{
IDecl dataDecl = declarations.FindByKey(data);
individualImports.Add($"from {dataDecl.Category} import {data.Name}");
}
else
{
packagesToImport.Add(PyExtensions.GetPackage(data));
}
}
foreach (var enumElement in decl.Elements.Where(d => d.Enum != null).Select(d => d.Enum))
{
if (PyExtensions.IsPackageEquals(decl, enumElement))
{
IDecl enumDecl = declarations.FindByKey(enumElement);
individualImports.Add($"from {enumDecl.Category} import {enumElement.Name}");
}
else
{
packagesToImport.Add(PyExtensions.GetPackage(enumElement));
}
}
foreach (var package in packagesToImport.Distinct())
{
writer.AppendLine($"import {package} as {PyExtensions.GetAlias(package)}");
}
foreach (var import in individualImports.Distinct())
{
writer.AppendLine(import);
}
}