output_access_demo/
output_access_demo.rs

1//! Demonstration of accessing outputs after execution
2//!
3//! This example shows how to access execution results for:
4//! - Regular sequential graphs
5//! - Branched graphs (parallel execution)
6//! - Variant parameter sweeps
7//! - Complex graphs with multiple outputs
8
9use graph_sp::Graph;
10use std::collections::HashMap;
11
12fn main() {
13    println!("═══════════════════════════════════════════════════════════");
14    println!("  Output Access Demo");
15    println!("  How to retrieve execution results");
16    println!("═══════════════════════════════════════════════════════════\n");
17    
18    demo_simple_output_access();
19    demo_branch_output_access();
20    demo_variant_output_access();
21    demo_multiple_outputs();
22}
23
24fn demo_simple_output_access() {
25    println!("─────────────────────────────────────────────────────────");
26    println!("Demo 1: Simple Pipeline Output Access");
27    println!("─────────────────────────────────────────────────────────\n");
28    
29    let mut graph = Graph::new();
30    
31    // Node 1: Generate initial data
32    graph.add(
33        |_: &HashMap<String, String>, _| {
34            let mut result = HashMap::new();
35            result.insert("initial_value".to_string(), "100".to_string());
36            result
37        },
38        Some("Source"),
39        None,
40        Some(vec![("initial_value", "raw_data")])  // Maps initial_value → raw_data
41    );
42    
43    // Node 2: Process the data
44    graph.add(
45        |inputs: &HashMap<String, String>, _| {
46            let value = inputs.get("input").unwrap().parse::<i32>().unwrap();
47            let mut result = HashMap::new();
48            result.insert("processed".to_string(), (value * 2).to_string());
49            result
50        },
51        Some("Process"),
52        Some(vec![("raw_data", "input")]),      // Maps raw_data → input
53        Some(vec![("processed", "final_result")])  // Maps processed → final_result
54    );
55    
56    // Build and execute
57    let dag = graph.build();
58    let context = dag.execute(false, None);
59    
60    println!("📦 Execution Context (all variables):");
61    for (key, value) in &context {
62        println!("  {} = {}", key, value);
63    }
64    
65    println!("\n🎯 Accessing specific outputs:");
66    
67    // Access by broadcast variable name (what's in the graph context)
68    if let Some(raw_data) = context.get("raw_data") {
69        println!("  raw_data: {}", raw_data);
70    }
71    
72    if let Some(final_result) = context.get("final_result") {
73        println!("  final_result: {}", final_result);
74    }
75    
76    // Check if a variable exists
77    if context.contains_key("final_result") {
78        println!("\n✅ Final result is available in context");
79    }
80    
81    println!();
82}
83
84fn demo_branch_output_access() {
85    println!("─────────────────────────────────────────────────────────");
86    println!("Demo 2: Branch Output Access (Parallel Paths)");
87    println!("─────────────────────────────────────────────────────────\n");
88    
89    let mut graph = Graph::new();
90    
91    // Source node
92    graph.add(
93        |_: &HashMap<String, String>, _| {
94            let mut result = HashMap::new();
95            result.insert("value".to_string(), "50".to_string());
96            result
97        },
98        Some("Source"),
99        None,
100        Some(vec![("value", "shared_data")])
101    );
102    
103    // Branch A: Statistics computation
104    let mut branch_a = Graph::new();
105    branch_a.add(
106        |inputs: &HashMap<String, String>, _| {
107            let val = inputs.get("data").unwrap();
108            let mut result = HashMap::new();
109            result.insert("stats_output".to_string(), format!("Stats of {}", val));
110            result
111        },
112        Some("Stats"),
113        Some(vec![("shared_data", "data")]),
114        Some(vec![("stats_output", "statistics")])  // Branch A produces "statistics"
115    );
116    
117    // Branch B: Model training
118    let mut branch_b = Graph::new();
119    branch_b.add(
120        |inputs: &HashMap<String, String>, _| {
121            let val = inputs.get("data").unwrap();
122            let mut result = HashMap::new();
123            result.insert("model_output".to_string(), format!("Model trained on {}", val));
124            result
125        },
126        Some("Train"),
127        Some(vec![("shared_data", "data")]),
128        Some(vec![("model_output", "model")])  // Branch B produces "model"
129    );
130    
131    // Branch C: Visualization
132    let mut branch_c = Graph::new();
133    branch_c.add(
134        |inputs: &HashMap<String, String>, _| {
135            let val = inputs.get("data").unwrap();
136            let mut result = HashMap::new();
137            result.insert("viz_output".to_string(), format!("Plot of {}", val));
138            result
139        },
140        Some("Visualize"),
141        Some(vec![("shared_data", "data")]),
142        Some(vec![("viz_output", "visualization")])  // Branch C produces "visualization"
143    );
144    
145    // Add branches to main graph
146    graph.branch(branch_a);
147    graph.branch(branch_b);
148    graph.branch(branch_c);
149    
150    // Execute
151    let dag = graph.build();
152    let context = dag.execute(false, None);
153    
154    println!("📦 All outputs from parallel branches:");
155    
156    // Access each branch's output
157    if let Some(stats) = context.get("statistics") {
158        println!("  Branch A (Statistics): {}", stats);
159    }
160    
161    if let Some(model) = context.get("model") {
162        println!("  Branch B (Model): {}", model);
163    }
164    
165    if let Some(viz) = context.get("visualization") {
166        println!("  Branch C (Visualization): {}", viz);
167    }
168    
169    println!("\n🔍 All variables in context:");
170    for (key, value) in &context {
171        println!("  {} = {}", key, value);
172    }
173    
174    println!();
175}
176
177fn demo_variant_output_access() {
178    println!("─────────────────────────────────────────────────────────");
179    println!("Demo 3: Variant Output Access (Parameter Sweep)");
180    println!("─────────────────────────────────────────────────────────\n");
181    
182    let mut graph = Graph::new();
183    
184    // Source node
185    graph.add(
186        |_: &HashMap<String, String>, _| {
187            let mut result = HashMap::new();
188            result.insert("value".to_string(), "10.0".to_string());
189            result
190        },
191        Some("DataSource"),
192        None,
193        Some(vec![("value", "input_data")])
194    );
195    
196    // Variant nodes: scale by different factors
197    // Factory function that creates a scaler for each factor
198    fn make_scaler(factor: f64) -> impl Fn(&HashMap<String, String>, &HashMap<String, String>) -> HashMap<String, String> {
199        move |inputs: &HashMap<String, String>, _| {
200            let value = inputs.get("data").unwrap().parse::<f64>().unwrap();
201            let mut result = HashMap::new();
202            result.insert("scaled".to_string(), (value * factor).to_string());
203            result
204        }
205    }
206    
207    graph.variant(
208        make_scaler,
209        vec![2.0, 3.0, 5.0],
210        Some("Scale"),
211        Some(vec![("input_data", "data")]),
212        Some(vec![("scaled", "result")])  // Each variant produces "result"
213    );
214    
215    // Execute
216    let dag = graph.build();
217    let context = dag.execute(false, None);
218    
219    println!("📦 Variant outputs:");
220    println!("  Note: Variants with same output name overwrite each other");
221    println!("  The last variant (factor=5.0) writes to 'result'\n");
222    
223    // Access the result (will be from the last variant)
224    if let Some(result) = context.get("result") {
225        println!("  result = {} (from last variant: 10.0 * 5.0)", result);
226    }
227    
228    println!("\n💡 Tip: To preserve all variant outputs, use unique output names:");
229    println!("   Option 1: Map each variant to a different broadcast variable");
230    println!("   Option 2: Collect results in merge node");
231    println!("   Option 3: Use variant_params or closure capture to distinguish");
232    
233    // Better approach: unique output names per variant
234    let mut graph2 = Graph::new();
235    
236    graph2.add(
237        |_: &HashMap<String, String>, _| {
238            let mut result = HashMap::new();
239            result.insert("value".to_string(), "10.0".to_string());
240            result
241        },
242        Some("DataSource"),
243        None,
244        Some(vec![("value", "input_data")])
245    );
246    
247    // Variant 1: 2x
248    fn make_scaler_unique(label: &str, factor: f64) -> impl Fn(&HashMap<String, String>, &HashMap<String, String>) -> HashMap<String, String> + '_ {
249        move |inputs: &HashMap<String, String>, _| {
250            let value = inputs.get("data").unwrap().parse::<f64>().unwrap();
251            let mut result = HashMap::new();
252            result.insert(label.to_string(), (value * factor).to_string());
253            result
254        }
255    }
256    
257    graph2.variant(
258        |_x: &str| make_scaler_unique("scaled_2x", 2.0),
259        vec!["2x"],
260        Some("Scale2x"),
261        Some(vec![("input_data", "data")]),
262        Some(vec![("scaled_2x", "result_2x")])
263    );
264    
265    graph2.variant(
266        |_x: &str| make_scaler_unique("scaled_3x", 3.0),
267        vec!["3x"],
268        Some("Scale3x"),
269        Some(vec![("input_data", "data")]),
270        Some(vec![("scaled_3x", "result_3x")])
271    );
272    
273    let dag2 = graph2.build();
274    let context2 = dag2.execute(false, None);
275    
276    println!("\n✅ Better approach - unique output names:");
277    if let Some(result_2x) = context2.get("result_2x") {
278        println!("  result_2x = {}", result_2x);
279    }
280    if let Some(result_3x) = context2.get("result_3x") {
281        println!("  result_3x = {}", result_3x);
282    }
283    
284    println!();
285}
286
287fn demo_multiple_outputs() {
288    println!("─────────────────────────────────────────────────────────");
289    println!("Demo 4: Multiple Outputs from Single Node");
290    println!("─────────────────────────────────────────────────────────\n");
291    
292    let mut graph = Graph::new();
293    
294    // Node that produces multiple outputs
295    graph.add(
296        |_: &HashMap<String, String>, _| {
297            let mut result = HashMap::new();
298            result.insert("mean".to_string(), "50.5".to_string());
299            result.insert("median".to_string(), "48.0".to_string());
300            result.insert("stddev".to_string(), "12.3".to_string());
301            result.insert("count".to_string(), "100".to_string());
302            result
303        },
304        Some("Statistics"),
305        None,
306        Some(vec![
307            ("mean", "stat_mean"),
308            ("median", "stat_median"),
309            ("stddev", "stat_stddev"),
310            ("count", "sample_count")
311        ])
312    );
313    
314    // Execute
315    let dag = graph.build();
316    let context = dag.execute(false, None);
317    
318    println!("📊 Multiple outputs from single node:");
319    
320    // Access each output individually
321    println!("  Mean:   {}", context.get("stat_mean").unwrap());
322    println!("  Median: {}", context.get("stat_median").unwrap());
323    println!("  StdDev: {}", context.get("stat_stddev").unwrap());
324    println!("  Count:  {}", context.get("sample_count").unwrap());
325    
326    println!("\n📋 Complete execution context:");
327    for (key, value) in &context {
328        println!("  {} = {}", key, value);
329    }
330    
331    println!("\n💡 Summary:");
332    println!("  ✓ dag.execute(false, None) returns HashMap<String, String>");
333    println!("  ✓ Keys are broadcast variable names (from output mappings)");
334    println!("  ✓ Use context.get(\"variable_name\") to access specific outputs");
335    println!("  ✓ All outputs accumulate in the context throughout execution");
336    
337    println!();
338}
output_access_demo/output_access_demo.rs

output_access_demo/
output_access_demo.rs
