mf_transform/
attr_step.rs

1use std::sync::Arc;
2
3use crate::{transform_error, TransformResult};
4
5use super::{
6    step::{Step, StepResult},
7};
8
9use mf_model::{schema::Schema, tree::Tree, types::NodeId};
10use serde::{Deserialize, Serialize};
11use serde_json::{Value};
12use mf_model::rpds::HashTrieMapSync;
13
14/// 节点属性变更步骤
15#[derive(Debug, Serialize, Deserialize, Clone)]
16pub struct AttrStep {
17    pub id: NodeId,
18    pub values: HashTrieMapSync<String, Value>,
19}
20
21impl AttrStep {
22    pub fn new(
23        id: NodeId,
24        values: HashTrieMapSync<String, Value>,
25    ) -> Self {
26        AttrStep { id, values }
27    }
28}
29
30impl Step for AttrStep {
31    fn name(&self) -> String {
32        "attr_step".to_string()
33    }
34
35    fn apply(
36        &self,
37        dart: &mut Tree,
38        schema: Arc<Schema>,
39    ) -> TransformResult<StepResult> {
40        let factory = schema.factory();
41        match dart.get_node(&self.id) {
42            Some(node) => {
43                // 获取节点类型定义，若缺失则返回错误而非 panic
44                let node_type = match factory.node_definition(&node.r#type) {
45                    Some(nt) => nt,
46                    None => {
47                        return Err(transform_error(format!(
48                            "未知的节点类型: {}",
49                            node.r#type
50                        )));
51                    },
52                };
53                let attr = &node_type.attrs;
54                // 删除 self.values 中 attr中没有定义的属性
55                let mut new_values = self.values.clone();
56                for (key, _) in self.values.iter() {
57                    if !attr.contains_key(key) {
58                        new_values.remove_mut(key);
59                    }
60                }
61                let result = dart.attrs(&self.id) + new_values;
62                match result {
63                    Ok(_) => Ok(StepResult::ok()),
64                    Err(e) => Err(transform_error(e.to_string())),
65                }
66            },
67            None => Err(transform_error("节点不存在".to_string())),
68        }
69    }
70
71    fn serialize(&self) -> Option<Vec<u8>> {
72        serde_json::to_vec(self).ok()
73    }
74
75    fn invert(
76        &self,
77        dart: &Arc<Tree>,
78    ) -> Option<Arc<dyn Step>> {
79        match dart.get_node(&self.id) {
80            Some(node) => {
81                // 仅对本次修改过的键生成反向值，避免覆盖无关属性
82                let mut revert_values = HashTrieMapSync::new_sync();
83                for (changed_key, _) in self.values.iter() {
84                    if let Some(old_val) = node.attrs.get_safe(changed_key) {
85                        revert_values
86                            .insert_mut(changed_key.clone(), old_val.clone());
87                    }
88                    // 若原先不存在该键，这里不设置（缺少删除语义）；
89                    // 如需彻底还原，可扩展支持 unset 语义
90                }
91                if revert_values.is_empty() {
92                    None
93                } else {
94                    Some(Arc::new(AttrStep::new(
95                        self.id.clone(),
96                        revert_values,
97                    )))
98                }
99            },
100            None => None,
101        }
102    }
103}
mf_transform/attr_step.rs

mf_transform/
attr_step.rs
