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Posted to commits@nifi.apache.org by jp...@apache.org on 2016/12/16 20:10:05 UTC
nifi git commit: NIFI-3206: Add ifElse function to Expression Language
Repository: nifi
Updated Branches:
refs/heads/master 34627f78b -> 21ed55669
NIFI-3206: Add ifElse function to Expression Language
This closes #1333
Signed-off-by: jpercivall <JP...@apache.org>
Project: http://git-wip-us.apache.org/repos/asf/nifi/repo
Commit: http://git-wip-us.apache.org/repos/asf/nifi/commit/21ed5566
Tree: http://git-wip-us.apache.org/repos/asf/nifi/tree/21ed5566
Diff: http://git-wip-us.apache.org/repos/asf/nifi/diff/21ed5566
Branch: refs/heads/master
Commit: 21ed556691719c592df89f36f0ccec26364e3997
Parents: 34627f7
Author: Matt Burgess <ma...@apache.org>
Authored: Thu Dec 15 13:12:55 2016 -0500
Committer: jpercivall <JP...@apache.org>
Committed: Fri Dec 16 15:13:01 2016 -0500
----------------------------------------------------------------------
.../language/antlr/AttributeExpressionLexer.g | 1 +
.../language/antlr/AttributeExpressionParser.g | 2 +-
.../attribute/expression/language/Query.java | 8 +++
.../evaluation/functions/IfElseEvaluator.java | 53 ++++++++++++++++++++
.../expression/language/TestQuery.java | 17 +++++++
.../asciidoc/expression-language-guide.adoc | 37 ++++++++++++--
6 files changed, 112 insertions(+), 6 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/nifi/blob/21ed5566/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionLexer.g
----------------------------------------------------------------------
diff --git a/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionLexer.g b/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionLexer.g
index 071fda9..6c0bcff 100644
--- a/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionLexer.g
+++ b/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionLexer.g
@@ -182,6 +182,7 @@ SUBSTRING : 'substring';
REPLACE : 'replace';
REPLACE_FIRST : 'replaceFirst';
REPLACE_ALL : 'replaceAll';
+IF_ELSE : 'ifElse';
// 4 arg functions
GET_DELIMITED_FIELD : 'getDelimitedField';
http://git-wip-us.apache.org/repos/asf/nifi/blob/21ed5566/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g
----------------------------------------------------------------------
diff --git a/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g b/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g
index 11cbec8..576f011 100644
--- a/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g
+++ b/nifi-commons/nifi-expression-language/src/main/antlr3/org/apache/nifi/attribute/expression/language/antlr/AttributeExpressionParser.g
@@ -77,7 +77,7 @@ zeroArgString : (TO_UPPER | TO_LOWER | TRIM | TO_STRING | URL_ENCODE | URL_DECOD
oneArgString : ((SUBSTRING_BEFORE | SUBSTRING_BEFORE_LAST | SUBSTRING_AFTER | SUBSTRING_AFTER_LAST | REPLACE_NULL | REPLACE_EMPTY |
PREPEND | APPEND | FORMAT | STARTS_WITH | ENDS_WITH | CONTAINS | JOIN | JSON_PATH | FROM_RADIX) LPAREN! anyArg RPAREN!) |
(TO_RADIX LPAREN! anyArg (COMMA! anyArg)? RPAREN!);
-twoArgString : ((REPLACE | REPLACE_FIRST | REPLACE_ALL) LPAREN! anyArg COMMA! anyArg RPAREN!) |
+twoArgString : ((REPLACE | REPLACE_FIRST | REPLACE_ALL | IF_ELSE) LPAREN! anyArg COMMA! anyArg RPAREN!) |
(SUBSTRING LPAREN! anyArg (COMMA! anyArg)? RPAREN!);
fiveArgString : GET_DELIMITED_FIELD LPAREN! anyArg (COMMA! anyArg (COMMA! anyArg (COMMA! anyArg (COMMA! anyArg)?)?)?)? RPAREN!;
http://git-wip-us.apache.org/repos/asf/nifi/blob/21ed5566/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/Query.java
----------------------------------------------------------------------
diff --git a/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/Query.java b/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/Query.java
index 06caf53..18396aa 100644
--- a/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/Query.java
+++ b/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/Query.java
@@ -54,6 +54,7 @@ import org.apache.nifi.attribute.expression.language.evaluation.functions.Greate
import org.apache.nifi.attribute.expression.language.evaluation.functions.GreaterThanOrEqualEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.functions.HostnameEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.functions.IPEvaluator;
+import org.apache.nifi.attribute.expression.language.evaluation.functions.IfElseEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.functions.InEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.functions.IndexOfEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.functions.IsEmptyEvaluator;
@@ -126,6 +127,7 @@ import org.antlr.runtime.CommonTokenStream;
import org.antlr.runtime.tree.Tree;
import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionParser.FROM_RADIX;
+import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionParser.IF_ELSE;
import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionParser.MATH;
import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionParser.ALL_ATTRIBUTES;
import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionParser.ALL_DELINEATED_VALUES;
@@ -1361,6 +1363,12 @@ public class Query {
return addToken(new JsonPathEvaluator(toStringEvaluator(subjectEvaluator),
toStringEvaluator(argEvaluators.get(0), "first argument to jsonPath")), "jsonPath");
}
+ case IF_ELSE: {
+ verifyArgCount(argEvaluators, 2, "ifElse");
+ return addToken(new IfElseEvaluator(toBooleanEvaluator(subjectEvaluator),
+ toStringEvaluator(argEvaluators.get(0), "argument to return if true"),
+ toStringEvaluator(argEvaluators.get(1), "argument to return if false")), "ifElse");
+ }
default:
throw new AttributeExpressionLanguageParsingException("Expected a Function-type expression but got " + tree.toString());
}
http://git-wip-us.apache.org/repos/asf/nifi/blob/21ed5566/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/evaluation/functions/IfElseEvaluator.java
----------------------------------------------------------------------
diff --git a/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/evaluation/functions/IfElseEvaluator.java b/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/evaluation/functions/IfElseEvaluator.java
new file mode 100644
index 0000000..79bc4a5
--- /dev/null
+++ b/nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/evaluation/functions/IfElseEvaluator.java
@@ -0,0 +1,53 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.attribute.expression.language.evaluation.functions;
+
+import org.apache.nifi.attribute.expression.language.evaluation.Evaluator;
+import org.apache.nifi.attribute.expression.language.evaluation.QueryResult;
+import org.apache.nifi.attribute.expression.language.evaluation.StringEvaluator;
+import org.apache.nifi.attribute.expression.language.evaluation.StringQueryResult;
+
+import java.util.Map;
+
+public class IfElseEvaluator extends StringEvaluator {
+
+ private final Evaluator<Boolean> subject;
+ private final Evaluator<String> trueEvaluator;
+ private final Evaluator<String> falseEvaluator;
+
+ public IfElseEvaluator(final Evaluator<Boolean> subject, final Evaluator<String> trueEvaluator, final Evaluator<String> falseEvaluator) {
+ this.subject = subject;
+ this.trueEvaluator = trueEvaluator;
+ this.falseEvaluator = falseEvaluator;
+ }
+
+ @Override
+ public QueryResult<String> evaluate(final Map<String, String> attributes) {
+ final QueryResult<Boolean> subjectValue = subject.evaluate(attributes);
+ if (subjectValue == null) {
+ return new StringQueryResult(null);
+ }
+ final String ifElseValue = (Boolean.TRUE.equals(subjectValue.getValue())) ? trueEvaluator.evaluate(attributes).getValue() : falseEvaluator.evaluate(attributes).getValue();
+ return new StringQueryResult(ifElseValue);
+ }
+
+ @Override
+ public Evaluator<?> getSubjectEvaluator() {
+ return subject;
+ }
+
+}
http://git-wip-us.apache.org/repos/asf/nifi/blob/21ed5566/nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestQuery.java
----------------------------------------------------------------------
diff --git a/nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestQuery.java b/nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestQuery.java
index b666b26..2dad9ca 100644
--- a/nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestQuery.java
+++ b/nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestQuery.java
@@ -1684,6 +1684,23 @@ public class TestQuery {
verifyEquals("${string:unescapeHtml4()}", attributes, "special \u2663");
}
+ @Test
+ public void testIfElse() {
+ final Map<String, String> attributes = new HashMap<>();
+ verifyEquals("${attr:isNull():ifElse('a', 'b')}", attributes, "a");
+ verifyEquals("${attr:ifElse('a', 'b')}", attributes, "b");
+ attributes.put("attr", "hello");
+ verifyEquals("${attr:isNull():ifElse('a', 'b')}", attributes, "b");
+ verifyEquals("${attr:ifElse('a', 'b')}", attributes, "b");
+ attributes.put("attr", "true");
+ verifyEquals("${attr:ifElse('a', 'b')}", attributes, "a");
+
+ verifyEquals("${attr2:isNull():ifElse('a', 'b')}", attributes, "a");
+ verifyEquals("${literal(true):ifElse('a', 'b')}", attributes, "a");
+ verifyEquals("${literal(true):ifElse(false, 'b')}", attributes, "false");
+
+ }
+
private void verifyEquals(final String expression, final Map<String, String> attributes, final Object expectedResult) {
verifyEquals(expression,attributes, null, expectedResult);
}
http://git-wip-us.apache.org/repos/asf/nifi/blob/21ed5566/nifi-docs/src/main/asciidoc/expression-language-guide.adoc
----------------------------------------------------------------------
diff --git a/nifi-docs/src/main/asciidoc/expression-language-guide.adoc b/nifi-docs/src/main/asciidoc/expression-language-guide.adoc
index 7af3be7..2b629e5 100644
--- a/nifi-docs/src/main/asciidoc/expression-language-guide.adoc
+++ b/nifi-docs/src/main/asciidoc/expression-language-guide.adoc
@@ -228,7 +228,7 @@ interpreted as literals. For example these two expressions are valid (without th
One of the most powerful features of the Expression Language is the ability to compare an attribute value against
some other value. This is used often, for example, to configure how a Processor should route data. The following
functions are used for performing boolean logic, such as comparing two values.
-Each of these functions returns a value of type Boolean.
+Each of these functions are designed to work on values of type Boolean.
[.function]
@@ -480,6 +480,37 @@ ${filename:toLower():equals( ${filename} ):or(
+[.function]
+=== ifElse
+
+*Description*: [.description]#Evaluates the first argument if the Subject evaluates to true, or the second argument
+if the Subject evaluates to false.#
+
+*Subject Type*: [.subject]#Boolean#
+
+*Arguments*:
+
+ - [.argName]#_EvaluateIfTrue_# : [.argDesc]#The value to return if the Subject is true#
+ - [.argName]#_EvaluateIfFalse_# : [.argDesc]#The value to return if the Subject is false#
+
+*Return Type*: [.returnType]#String#
+
+*Examples*: If the "filename" attribute has the value "a brand new filename.txt", the "nullFilename" attribute has
+the value null, and the "bool" attribute has the value "true", then the following expressions will provide
+the following results:
+
+
+
+.ifElse Examples
+|===================================================================
+| Expression | Value
+| `${bool:ifElse('a','b')}` | `a`
+| `${literal(true):ifElse('a','b')}` | `a`
+| `${nullFilename:isNull():ifElse('file does not exist', 'located file')}` | `file does not exist`
+| `${nullFilename:ifElse('found', 'not_found')}` | `not_found`
+| `${filename:ifElse('found', 'not_found')}` | `not_found`
+| `${filename:isNull():not():ifElse('found', 'not_found')}` | `found`
+|===================================================================
@@ -963,10 +994,6 @@ Expressions will provide the following results:
will return 0.
-
-
-
-
[[encode]]
== Encode/Decode Functions