Struct pgx_utils::sql_entity_graph::ToSqlConfigEntity

pub struct ToSqlConfigEntity {
    pub enabled: bool,
    pub callback: Option<fn(_: &SqlGraphEntity, _: &PgxSql) -> Result<String, Box<dyn Error + Send + Sync + 'static>>>,
    pub content: Option<&'static str>,
}

Represents configuration options for tuning the SQL generator.

When an item that can be rendered to SQL has these options at hand, they should be respected. If an item does not have them, then it is not expected that the SQL generation for those items can be modified.

The default configuration has enabled set to true, and callback to None, which indicates that the default SQL generation behavior will be used. These are intended to be mutually exclusive options, so callback should only be set if generation is enabled.

When enabled is false, no SQL is generated for the item being configured.

When callback has a value, the corresponding ToSql implementation should invoke the callback instead of performing their default behavior.

Fields

enabled: bool

callback: Option<fn(_: &SqlGraphEntity, _: &PgxSql) -> Result<String, Box<dyn Error + Send + Sync + 'static>>>

content: Option<&'static str>

Implementations

impl ToSqlConfigEntity

pub fn to_sql(
    &self,
    entity: &SqlGraphEntity,
    context: &PgxSql
) -> Option<Result<String>>

Given a SqlGraphEntity, this function converts it to SQL based on the current configuration.

If the config overrides the default behavior (i.e. using the ToSql trait), then Some(eyre::Result) is returned. If the config does not override the default behavior, then None is returned. This can be used to dispatch SQL generation in a single line, e.g.:

config.to_sql(entity, context).unwrap_or_else(|| entity.to_sql(context))?

Trait Implementations

impl Clone for ToSqlConfigEntity

fn clone(&self) -> ToSqlConfigEntity

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ToSqlConfigEntity

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ToSqlConfigEntity

fn default() -> ToSqlConfigEntity

Returns the “default value” for a type.

impl Hash for ToSqlConfigEntity

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where
    H: Hasher,
    Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq<ToSqlConfigEntity> for ToSqlConfigEntity

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for ToSqlConfigEntity