Method from_model

django/db/migrations/state.py:799–932

Given a model, return a ModelState representing it.

(cls, model, exclude_rels=False)

    @classmethod
    def from_model(cls, model, exclude_rels=False):
        """Given a model, return a ModelState representing it."""
        # Deconstruct the fields
        fields = []
        for field in model._meta.local_fields:
            if getattr(field, "remote_field", None) and exclude_rels:
                continue
            if isinstance(field, models.OrderWrt):
                continue
            name = field.name
            try:
                fields.append((name, field.clone()))
            except TypeError as e:
                raise TypeError(
                    "Couldn't reconstruct field %s on %s: %s"
                    % (
                        name,
                        model._meta.label,
                        e,
                    )
                )
        if not exclude_rels:
            for field in model._meta.local_many_to_many:
                name = field.name
                try:
                    fields.append((name, field.clone()))
                except TypeError as e:
                    raise TypeError(
                        "Couldn't reconstruct m2m field %s on %s: %s"
                        % (
                            name,
                            model._meta.object_name,
                            e,
                        )
                    )
        # Extract the options
        options = {}
        for name in DEFAULT_NAMES:
            # Ignore some special options
            if name in ["apps", "app_label"]:
                continue
            elif name in model._meta.original_attrs:
                if name == "unique_together":
                    ut = model._meta.original_attrs["unique_together"]
                    options[name] = set(normalize_together(ut))
                elif name == "indexes":
                    indexes = [idx.clone() for idx in model._meta.indexes]
                    for index in indexes:
                        if not index.name:
                            index.set_name_with_model(model)
                    options["indexes"] = indexes
                elif name == "constraints":
                    options["constraints"] = [
                        con.clone() for con in model._meta.constraints
                    ]
                else:
                    options[name] = model._meta.original_attrs[name]
        # If we're ignoring relationships, remove all field-listing model