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|
pub fn select<C>(
dbconn: &rusqlite::Connection,
table_name: &str,
record_id: &str,
exclude_columns: &[C],
) -> Result<yaml_rust::Yaml, crate::Error>
where C: AsRef<str> + PartialEq<String>
{
select_by_column(
dbconn,
table_name,
&crate::sqlite::table_primary_key_column(dbconn, table_name)?,
record_id,
exclude_columns,
)
}
pub fn select_by_column<C>(
dbconn: &rusqlite::Connection,
table_name: &str,
primary_key_column: &str,
record_id: &str,
exclude_columns: &[C],
) -> Result<yaml_rust::Yaml, crate::Error>
where C: AsRef<str> + PartialEq<String>
{
use crate::yaml::Yaml;
let mut stmt = dbconn.prepare(
&format!(
r#"
SELECT
*
FROM "{}"
WHERE "{}" = :pk;
"#,
table_name,
primary_key_column,
),
)?;
let column_names: Vec<String> = stmt
.column_names()
.into_iter()
.map(String::from)
.collect();
let rows = stmt.query_map(
rusqlite::named_params! {
":pk": record_id,
},
|row| {
let mut data = yaml_rust::yaml::Hash::new();
for (i, column) in column_names.iter().enumerate() {
// Don't include excluded columns in the resulting hash.
if exclude_columns.iter().any(|c| c == column) {
continue
}
let column_name = column.to_owned();
let column_value: Yaml = row.get(i)?;
data.insert(
yaml_rust::Yaml::String(column_name),
column_value.into_inner(),
);
}
Ok(data)
},
)?;
// Only one record is expected.
let mut records = yaml_rust::yaml::Array::with_capacity(1);
for row_result in rows {
records.push(yaml_rust::Yaml::Hash(row_result?));
}
match records.len() {
0 => Ok(yaml_rust::Yaml::Null),
1 => Ok(records.swap_remove(0)),
_ => Ok(yaml_rust::Yaml::Array(records)),
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn select_extracts_a_database_record_as_yaml() {
struct TestRecord {
count: i16,
description: String,
}
let record = TestRecord {
count: 99,
description: "This is a test.
With multiple paragraphs.".to_owned(),
};
let mut yaml_hash = yaml_rust::yaml::Hash::new();
yaml_hash.insert(
yaml_rust::Yaml::String("count".to_owned()),
yaml_rust::Yaml::Integer(record.count.into()),
);
yaml_hash.insert(
yaml_rust::Yaml::String("description".to_owned()),
yaml_rust::Yaml::String(record.description.clone()),
);
let expected = yaml_rust::Yaml::Hash(yaml_hash);
let conn = rusqlite::Connection::open_in_memory().unwrap();
conn.execute(
r#"
CREATE TABLE "test" (
id INTEGER PRIMARY KEY,
count INTEGER,
description TEXT
);
"#,
[]
).unwrap();
{
let mut stmt = conn.prepare(r#"
INSERT INTO "test"
(count, description)
VALUES
(?, ?);
"#).unwrap();
stmt.insert(
rusqlite::params![record.count, record.description],
).unwrap();
let got = select(&conn, "test", "1").unwrap();
assert_eq!(expected, got);
}
conn.close().unwrap();
}
}
|
