Use python's json library for generating JSON output

In the process, also removed code (or query) duplication in fetchSamples
method, which now becomes a @classmethod. Also preferred to use string
formatting to string concatenation.

Reviewed-By: jasplin

1 files changed, 31 insertions, 46 deletions

diff --git a/scripts/getresultdetails2.py b/scripts/getresultdetails2.py
index b0d429c..8678b52 100644
--- a/scripts/getresultdetails2.py
+++ b/scripts/getresultdetails2.py
@@ -1,3 +1,6 @@
+import sys
+import json
+
 from dbaccess import execQuery
 from misc import textToId, printJSONHeader
 
@@ -29,60 +32,42 @@ class GetResultDetails2:
         self.metric_id = textToId("metric", metric)
 
     def execute(self):
-        self.sample1, self.sample2 = self.fetchSamples()
+        self.sample2 = self.fetchSample(self.host1_id, self.platform1_id,
+                self.branch1_id, self.sha11_id, self.benchmark_id,
+                self.metric_id)
+        self.sample2 = self.fetchSample(self.host2_id, self.platform2_id,
+                self.branch2_id, self.sha12_id, self.benchmark_id,
+                self.metric_id)
         self.writeOutput()
 
     # Fetches the sample (i.e. individual observations) for both contexts.
-    def fetchSamples(self):
+    @classmethod
+    def fetchSample(cls, host, platform, branch, sha1, benchmark, metric):
 
-        sample1 = execQuery(
-            "SELECT value, valid, extract(epoch FROM startTime)::int " +
-            "FROM result, upload WHERE uploadId = upload.id" +
-            " AND hostId = " + str(self.host1_id) +
-            " AND platformId = " + str(self.platform1_id) + " AND branchId = " +
-            str(self.branch1_id) + " AND sha1Id = " + str(self.sha11_id) +
-            " AND benchmarkId = " + str(self.benchmark_id) +
-            " AND metricId = " + str(self.metric_id) +
-            " ORDER BY value DESC;"
-            )
-        sample2 = execQuery(
-            "SELECT value, valid, extract(epoch FROM startTime)::int " +
-            "FROM result, upload WHERE uploadId = upload.id" +
-            " AND hostId = " + str(self.host2_id) +
-            " AND platformId = " + str(self.platform2_id) + " AND branchId = " +
-            str(self.branch2_id) + " AND sha1Id = " + str(self.sha12_id) +
-            " AND benchmarkId = " + str(self.benchmark_id) +
-            " AND metricId = " + str(self.metric_id) +
-            " ORDER BY value DESC;"
-            )
+        sample = []
+        for value, valid, timestamp in execQuery(
+                "SELECT value, valid, EXTRACT(EPOCH FROM startTime)::INT"
+                " FROM result, upload"
+                " WHERE uploadId = upload.id"
+                " AND hostId = %d"
+                " AND platformId = %d"
+                " AND branchId = %d"
+                " AND sha1Id = %d"
+                " AND benchmarkId = %d"
+                " AND metricId = %d"
+                " ORDER BY value DESC;"
+                    % (host, platform, branch, sha1, benchmark, metric)):
+            sample.append({
+                    'value' : value,
+                    'valid' : valid,
+                    'timestamp' : timestamp
+                })
 
-        return sample1, sample2
+        return sample
 
     def writeOutputAsJSON(self):
         printJSONHeader()
-        print "{"
-
-        first_sample_row = True;
-        for s in (("1", self.sample1), ("2", self.sample2)):
-            if not first_sample_row:
-                print ","
-            first_sample_row = False
-
-            print "\"sample" + s[0] + "\": ["
-            first_obs_row = True
-            for obs in s[1]:
-                if not first_obs_row:
-                    print ","
-                first_obs_row = False
-
-                print (
-                    "{\"value\": \"" + str(obs[0]) + "\", \"valid\": " +
-                    ("1" if obs[1] else "0") + ", \"timestamp\":" +
-                    "\"" + str(obs[2]) + "\" }");
-            print "]"
-
-        print "}"
-
+        json.dump({ 'sample1' : self.sample1, 'sample2' : self.sample2 }, sys.stdout)
 
 class GetResultDetails2AsJSON(GetResultDetails2):
     def writeOutput(self):