pgrx_sql_entity_graph/postgres_hash/
mod.rs

1//LICENSE Portions Copyright 2019-2021 ZomboDB, LLC.
2//LICENSE
3//LICENSE Portions Copyright 2021-2023 Technology Concepts & Design, Inc.
4//LICENSE
5//LICENSE Portions Copyright 2023-2023 PgCentral Foundation, Inc. <contact@pgcentral.org>
6//LICENSE
7//LICENSE All rights reserved.
8//LICENSE
9//LICENSE Use of this source code is governed by the MIT license that can be found in the LICENSE file.
10/*!
11
12`#[derive(PostgresHash)]` related macro expansion for Rust to SQL translation
13
14> Like all of the [`sql_entity_graph`][crate] APIs, this is considered **internal**
15> to the `pgrx` framework and very subject to change between versions. While you may use this, please do it with caution.
16
17*/
18pub mod entity;
19
20use crate::enrich::{ToEntityGraphTokens, ToRustCodeTokens};
21use proc_macro2::TokenStream as TokenStream2;
22use quote::{format_ident, quote};
23use syn::parse::{Parse, ParseStream};
24use syn::{DeriveInput, Ident};
25
26use crate::{CodeEnrichment, ToSqlConfig};
27
28/// A parsed `#[derive(PostgresHash)]` item.
29///
30/// It should be used with [`syn::parse::Parse`] functions.
31///
32/// Using [`quote::ToTokens`] will output the declaration for a `pgrx::datum::pgrx_sql_entity_graph::InventoryPostgresHash`.
33///
34/// On structs:
35///
36/// ```rust
37/// use syn::{Macro, parse::Parse, parse_quote, parse};
38/// use quote::{quote, ToTokens};
39/// use pgrx_sql_entity_graph::PostgresHash;
40///
41/// # fn main() -> eyre::Result<()> {
42/// use pgrx_sql_entity_graph::CodeEnrichment;
43/// let parsed: CodeEnrichment<PostgresHash> = parse_quote! {
44///     #[derive(PostgresHash)]
45///     struct Example<'a> {
46///         demo: &'a str,
47///     }
48/// };
49/// let sql_graph_entity_tokens = parsed.to_token_stream();
50/// # Ok(())
51/// # }
52/// ```
53///
54/// On enums:
55///
56/// ```rust
57/// use syn::{Macro, parse::Parse, parse_quote, parse};
58/// use quote::{quote, ToTokens};
59/// use pgrx_sql_entity_graph::PostgresHash;
60///
61/// # fn main() -> eyre::Result<()> {
62/// use pgrx_sql_entity_graph::CodeEnrichment;
63/// let parsed: CodeEnrichment<PostgresHash> = parse_quote! {
64///     #[derive(PostgresHash)]
65///     enum Demo {
66///         Example,
67///     }
68/// };
69/// let sql_graph_entity_tokens = parsed.to_token_stream();
70/// # Ok(())
71/// # }
72/// ```
73#[derive(Debug, Clone)]
74pub struct PostgresHash {
75    pub name: Ident,
76    pub to_sql_config: ToSqlConfig,
77}
78
79impl PostgresHash {
80    pub fn new(
81        name: Ident,
82        to_sql_config: ToSqlConfig,
83    ) -> Result<CodeEnrichment<Self>, syn::Error> {
84        if !to_sql_config.overrides_default() {
85            crate::ident_is_acceptable_to_postgres(&name)?;
86        }
87        Ok(CodeEnrichment(Self { name, to_sql_config }))
88    }
89
90    pub fn from_derive_input(
91        derive_input: DeriveInput,
92    ) -> Result<CodeEnrichment<Self>, syn::Error> {
93        let to_sql_config =
94            ToSqlConfig::from_attributes(derive_input.attrs.as_slice())?.unwrap_or_default();
95        Self::new(derive_input.ident, to_sql_config)
96    }
97}
98
99impl ToEntityGraphTokens for PostgresHash {
100    fn to_entity_graph_tokens(&self) -> TokenStream2 {
101        let name = &self.name;
102        let sql_graph_entity_fn_name = format_ident!("__pgrx_internals_hash_{}", self.name);
103        let to_sql_config = &self.to_sql_config;
104        quote! {
105            #[no_mangle]
106            #[doc(hidden)]
107            #[allow(nonstandard_style, unknown_lints, clippy::no_mangle_with_rust_abi)]
108            pub extern "Rust" fn  #sql_graph_entity_fn_name() -> ::pgrx::pgrx_sql_entity_graph::SqlGraphEntity {
109                use core::any::TypeId;
110                extern crate alloc;
111                use alloc::vec::Vec;
112                use alloc::vec;
113                let submission = ::pgrx::pgrx_sql_entity_graph::PostgresHashEntity {
114                    name: stringify!(#name),
115                    file: file!(),
116                    line: line!(),
117                    full_path: core::any::type_name::<#name>(),
118                    module_path: module_path!(),
119                    id: TypeId::of::<#name>(),
120                    to_sql_config: #to_sql_config,
121                };
122                ::pgrx::pgrx_sql_entity_graph::SqlGraphEntity::Hash(submission)
123            }
124        }
125    }
126}
127
128impl ToRustCodeTokens for PostgresHash {}
129
130impl Parse for CodeEnrichment<PostgresHash> {
131    fn parse(input: ParseStream) -> Result<Self, syn::Error> {
132        use syn::Item;
133
134        let parsed = input.parse()?;
135        let (ident, attrs) = match &parsed {
136            Item::Enum(item) => (item.ident.clone(), item.attrs.as_slice()),
137            Item::Struct(item) => (item.ident.clone(), item.attrs.as_slice()),
138            _ => return Err(syn::Error::new(input.span(), "expected enum or struct")),
139        };
140
141        let to_sql_config = ToSqlConfig::from_attributes(attrs)?.unwrap_or_default();
142        PostgresHash::new(ident, to_sql_config)
143    }
144}
pgrx_sql_entity_graph/postgres_hash/mod.rs

pgrx_sql_entity_graph/postgres_hash/
mod.rs
