Merge pull request #1467 from matthiasbeyer/libimagentryfilter/failable

libimagentryfilter: failable

lib/entry/libimagentryfilter/Cargo.toml

@@ -27,6 +27,7 @@ regex = "0.2"
 semver = "0.8"
 toml = "0.4"
 toml-query = "0.6"
+error-chain = "0.11"
 
 libimagstore    = { version = "0.8.0", path = "../../../lib/core/libimagstore" }
 libimagentrytag = { version = "0.8.0", path = "../../../lib/entry/libimagentrytag" }

lib/entry/libimagentryfilter/src/builtin/header/field_eq.rs

@@ -22,7 +22,9 @@ use libimagstore::store::Entry;
 use builtin::header::field_path::FieldPath;
 use builtin::header::field_predicate::FieldPredicate;
 use builtin::header::field_predicate::Predicate;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 use toml::Value;
 
@@ -53,9 +55,10 @@ impl FieldEq {
 
 }
 
-impl Filter<Entry> for FieldEq {
+impl FailableFilter<Entry> for FieldEq {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
+    fn filter(&self, e: &Entry) -> Result<bool> {
         self.filter.filter(e)
     }
 

lib/entry/libimagentryfilter/src/builtin/header/field_exists.rs

@@ -20,7 +20,9 @@
 use libimagstore::store::Entry;
 
 use toml_query::read::TomlValueReadExt;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 use builtin::header::field_path::FieldPath;
 
@@ -38,10 +40,11 @@ impl FieldExists {
 
 }
 
-impl Filter<Entry> for FieldExists {
+impl FailableFilter<Entry> for FieldExists {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
-        e.get_header().read(&self.header_field_path[..]).is_ok()
+    fn filter(&self, e: &Entry) -> Result<bool> {
+        e.get_header().read(&self.header_field_path[..]).map_err(FE::from).map(|o| o.is_some())
     }
 
 }

lib/entry/libimagentryfilter/src/builtin/header/field_grep.rs

@@ -25,7 +25,9 @@ use libimagstore::store::Entry;
 use builtin::header::field_path::FieldPath;
 use builtin::header::field_predicate::FieldPredicate;
 use builtin::header::field_predicate::Predicate;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 struct EqGrep{
     regex: Regex
@@ -57,9 +59,10 @@ impl FieldGrep {
 
 }
 
-impl Filter<Entry> for FieldGrep {
+impl FailableFilter<Entry> for FieldGrep {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
+    fn filter(&self, e: &Entry) -> Result<bool> {
         self.filter.filter(e)
     }
 

lib/entry/libimagentryfilter/src/builtin/header/field_gt.rs

@@ -22,7 +22,9 @@ use libimagstore::store::Entry;
 use builtin::header::field_path::FieldPath;
 use builtin::header::field_predicate::FieldPredicate;
 use builtin::header::field_predicate::Predicate;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 use toml::Value;
 
@@ -69,9 +71,10 @@ impl FieldGt {
 
 }
 
-impl Filter<Entry> for FieldGt {
+impl FailableFilter<Entry> for FieldGt {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
+    fn filter(&self, e: &Entry) -> Result<bool> {
         self.filter.filter(e)
     }
 

lib/entry/libimagentryfilter/src/builtin/header/field_isempty.rs

@@ -21,7 +21,9 @@ use libimagstore::store::Entry;
 use toml_query::read::TomlValueReadExt;
 
 use builtin::header::field_path::FieldPath;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 use toml::Value;
 
@@ -39,23 +41,25 @@ impl FieldIsEmpty {
 
 }
 
-impl Filter<Entry> for FieldIsEmpty {
+impl FailableFilter<Entry> for FieldIsEmpty {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
-        e.get_header()
-            .read(&self.header_field_path[..])
+    fn filter(&self, e: &Entry) -> Result<bool> {
+        Ok(e
+             .get_header()
+             .read(&self.header_field_path[..])?
              .map(|v| {
                  match v {
-                    Some(&Value::Array(ref a))   => a.is_empty(),
-                    Some(&Value::String(ref s))  => s.is_empty(),
-                    Some(&Value::Table(ref t))   => t.is_empty(),
-                    Some(&Value::Boolean(_)) |
-                    Some(&Value::Float(_))   |
-                    Some(&Value::Integer(_)) => false,
-                    _                       => true,
+                     &Value::Array(ref a)   => a.is_empty(),
+                     &Value::String(ref s)  => s.is_empty(),
+                     &Value::Table(ref t)   => t.is_empty(),
+                     &Value::Boolean(_)  |
+                     &Value::Float(_)    |
+                     &Value::Datetime(_) |
+                     &Value::Integer(_)  => false,
                  }
              })
-            .unwrap_or(false)
+             .unwrap_or(true))
     }
 
 }

lib/entry/libimagentryfilter/src/builtin/header/field_istype.rs

@@ -22,7 +22,9 @@ use libimagstore::store::Entry;
 use builtin::header::field_path::FieldPath;
 use builtin::header::field_predicate::FieldPredicate;
 use builtin::header::field_predicate::Predicate;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 use toml::Value;
 
@@ -78,9 +80,10 @@ impl FieldIsType {
 
 }
 
-impl Filter<Entry> for FieldIsType {
+impl FailableFilter<Entry> for FieldIsType {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
+    fn filter(&self, e: &Entry) -> Result<bool> {
         self.filter.filter(e)
     }
 

lib/entry/libimagentryfilter/src/builtin/header/field_lt.rs

@@ -22,7 +22,9 @@ use libimagstore::store::Entry;
 use builtin::header::field_path::FieldPath;
 use builtin::header::field_predicate::FieldPredicate;
 use builtin::header::field_predicate::Predicate;
-use filters::filter::Filter;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 use toml::Value;
 
@@ -69,9 +71,10 @@ impl FieldLt {
 
 }
 
-impl Filter<Entry> for FieldLt {
+impl FailableFilter<Entry> for FieldLt {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
+    fn filter(&self, e: &Entry) -> Result<bool> {
         self.filter.filter(e)
     }
 

lib/entry/libimagentryfilter/src/builtin/header/field_predicate.rs

@@ -20,17 +20,22 @@
 use libimagstore::store::Entry;
 
 use toml_query::read::TomlValueReadExt;
+use toml::Value;
 
 use builtin::header::field_path::FieldPath;
-use filters::filter::Filter;
-
-use toml::Value;
+use filters::failable::filter::FailableFilter;
+use error::Result;
+use error::FilterError as FE;
 
 pub trait Predicate {
     fn evaluate(&self, &Value) -> bool;
 }
 
 /// Check whether certain header field in a entry is equal to a value
+///
+/// # Notice
+///
+/// Returns false if the value is not present.
 pub struct FieldPredicate<P: Predicate> {
     header_field_path: FieldPath,
     predicate: Box<P>,
@@ -47,15 +52,16 @@ impl<P: Predicate> FieldPredicate<P> {
 
 }
 
-impl<P: Predicate> Filter<Entry> for FieldPredicate<P> {
+impl<P: Predicate> FailableFilter<Entry> for FieldPredicate<P> {
+    type Error = FE;
 
-    fn filter(&self, e: &Entry) -> bool {
-        e.get_header()
-            .read(&self.header_field_path[..])
-            .map(|val| val.map(|v| (*self.predicate).evaluate(v)).unwrap_or(false))
+    fn filter(&self, e: &Entry) -> Result<bool> {
+        Ok(e.get_header()
+            .read(&self.header_field_path[..])?
+            .map(|v| (*self.predicate).evaluate(v))
             .unwrap_or(false)
+            )
     }
 
 }
 
-

lib/entry/libimagentryfilter/src/error.rs

@@ -17,3 +17,18 @@
 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 //
 
+error_chain! {
+
+    types {
+        FilterError, FilterErrorKind, ResultExt, Result;
+    }
+
+    foreign_links {
+        TomlQueryError(::toml_query::error::Error);
+    }
+
+    errors {
+    }
+
+}
+

lib/entry/libimagentryfilter/src/lib.rs

@@ -38,6 +38,7 @@ extern crate regex;
 extern crate semver;
 extern crate toml;
 extern crate toml_query;
+#[macro_use] extern crate error_chain;
 
 extern crate libimagstore;
 extern crate libimagentrytag;
@@ -45,8 +46,8 @@ extern crate libimagentrytag;
 // core functionality modules of the crate,
 // these depend only on libimagstore
 
-pub mod cli;
 pub mod builtin;
+pub mod error;
 
 // extended functionality of the crate
 // these depend on other internal libraries than libimagstore and use the upper core modules for